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Other Presentations - Department of Computer Science - University of Cyprus
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Pavlos Antoniou
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Monday, May 21, 2012
Time: 09:30-10:30 EET
Hosts: Andreas Pitsillides (Andreas.Pitsillides AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2012.antoniou
Abstract:
Complex collective behaviors and collective intelligence in groups of animals and insects found in nature look appealing for Wireless Sensor Network (WSN) congestion control because they emerge from simple local interactions of the individuals in the system. Animal and insect societies possess inherent properties like simplicity, scalability, self-adaptiveness to internal or external changes and robustness against threats. This thesis proposes two novel nature-inspired congestion avoidance approaches in WSNs that aim at managing the traffic injected into the network and thus improving performance, in particular with respect to packet delivery ratio, end-to-end delay and energy consumption. More specifically, the obstacle avoidance behavior of bird flocks and the competitive coexistence behavior of species sharing some limiting resource serve as the basis for developing the two novel approaches, addressing two different application scenarios in a resource-constrained environment. The first approach targets event-based applications in WSNs and adopts a swarm intelligence paradigm inspired by the obstacle avoidance behavior and the orientation behavior of bird flocks towards a global attractor, having global self-* properties (e.g. self-adaptation) achieved collectively without explicitly programming them into individual nodes. The main idea is to manage traffic by ‘guiding’ packets (birds) to form flocks and flow towards the sink node (global attractor), whilst trying to avoid congestion regions and dead nodes (obstacles). Performance evaluations show the effectiveness of the Flock-CC approach in balancing the offered load by exploiting available network resources. Flock-CC provides graceful performance degradation in terms of packet delivery ratio, packet loss, delay and energy tax as the traffic loads increase, to even extreme traffic loads. In addition, the proposed approach achieves adaptation to changing network and traffic conditions, robustness against failing nodes, scalability in different network sizes and outperforms typical conventional approaches. The second approach targets streaming applications in WSNs and focuses on how congestion can be gracefully handled in small-scale networks by regulating the rate of each traffic flow based on the Lotka-Volterra population model. The Lotka-Volterra based congestion control (LVCC) strategy involves minimal exchange of information and computation burden and is simple to implement at the individual node. Performance evaluations reveal that the LVCC approach achieves adaptability to changing traffic loads, scalability and fairness among flows, while providing graceful performance degradation as the offered load increases.
Short Bio:
Pavlos Antoniou is a Ph.D. candidate at the Department of Computer Science, University of Cyprus under the guidance of Dr. Andreas Pitsillides. He received a Diploma in Electrical and Computer Engineering (Dipl.-Ing.) from the National Technical University of Athens (NTUA), Greece, in 2005. He worked for the UCY-funded ADAVIDEO project from Sept. 2005 to Oct. 2006, for the EU-funded GINSENG project from Sept. 2008 to June 2009 and for the IPE-funded MiND2C project from Dec. 2008 to June 2009. From July 2009 he belongs to the Special Teaching Staff of the Department of Computer Science. He is also a member of the Networks Research Laboratory (NetRL). His research interests involve nature-inspired approaches (e.g. the bird flocking behavior) and mathematical models of population biology (e.g. the Lotka-Volterra model), for avoiding congestion in wireless sensor networks.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Dimitrios Kouzapas
Affiliation: Imperial College London, UK
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Thursday, April 26, 2012
Time: 15:00-16:00 EET
Hosts: Anna Philippou (anna AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2012.kouzapas
Abstract:
Εδώ και αρκετά χρόνια τα κατανεμημένα συστήματα μελετούνται ενδελεχώς με σκοπό την αξιοποίηση των δυνατότητων των μοντέρνων μηχανών υπολογισμού και δικτύων. Ο μαθηματικός λογισμός ήταν πάντα το κατεξοχήν εργαλείο για το συνεπή και ολοκληρωμένο ορισμό υπολογιστικών μοντέλων και συστήματων.
Η παρουσίαση αυτή θα αναφερθεί στην ανάπτυξη του π-λογισμού (π-calculus) ως το σημείο αναφοράς για τη θεωρητική μελέτη των κατανεμημένων συστημάτων και της επικοινωνίας μηνυμάτων (message passing) σαν θεμελιώδη συνάρτηση υπολογισμού.
Στην συνέχεια θα δούμε πως η ανάπτυξη και η μελέτη συστήματων τύπων (type systems) για τον π-λογισμό, ξεκίνησε να αναδιπλώνει τις ιδιότητες των κατανεμημένων συστημάτων και της επικοινωνίας. Πιο συγκεκριμένα θα παρουσιαστεί το σύστημα τύπων session types και οι μέχρι τώρα εφαρμογές του. Θα παρουσιαστεί η γλώσσα προγραμματισμού Session Java, η θεωρία χορογραφίας επικοινωνίας και τα session types, ο προγραμματισμός πρωτόκολλων δικτύου μέσω session types και η γλώσσα περιγραφής πρωτοκόλλων Scribble.
Short Bio:
Ο Δημήτρης Κουζαπάς είναι υποψήφιος διδακτορικού διπλώματος στο Imperial College London υπό την επίβλεψη της Dr. N. Yoshida. Ολοκλήρωσε τις προπτυχιακές του σπουδές στο Τμήμα Πληροφορικής του Πανεπιστημίου Κύπρου, BSc. 2008. Το 2009 αποφοίτησε από το Imperial College London με τον τίτλο MSc. in Advanced Computing. Τα ερευνητικά του ενδιαφέροντα βρίσκονται στα πεδία του θεωρητικού κατανεμημένου υπολογισμού, της επαλήθευσης κατανεμημένων συστημάτων, των γλωσσών προγραμματισμού και του προγραμματισμού κατανεμημένων συστημάτων.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Marios Kleanthous
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Friday, April 6, 2012
Time: 10:30-11:30 EET
Hosts: Yanos Sazeides (yanos AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2012.kleanthous
Abstract:
The importance of caches and memory hierarchy has increased over time due to
the growing gap between processor and memory performance, and it has become
more important in Simultaneous Multithreading processors and
Chip-multiprocessors. To cover this memory gap, caches have been the subject
of numerous studies aiming to improve their performance as well as their
power and area efficiency.
This thesis identifies a new phenomenon in caches that has the potential to
improve cache performance and efficiency: the Cache Content Duplication
(CCD). CCD occurs when there is a miss for a block in a cache and the entire
content of the missed block is already in the cache in a block with a
different tag. Caches aware of content-duplication can have lower miss
penalty by fetching, on a miss to a duplicate block, directly from the cache
instead of accessing lower in the memory hierarchy, and can have lower miss
rates by allowing only blocks with unique content to enter a cache.
The usefulness of CCD is also examined at all levels of the memory
hierarchy. First, we show that CCD is a frequent phenomenon for instruction
caches and that an idealized duplication-detection mechanism for instruction
caches has the potential to increase performance of an out-of-order
processor, with a 16KB, 8-way, 8 instructions per block instruction cache,
often by more than 10% and up to 36%. We also propose CATCH, a hardware
mechanism for dynamically detecting CCD for instruction caches. Experimental
results for an out-of-order processor show that a duplication-detection
mechanism with a 1.38KB cost captures on average 58% of the CCD's idealized
potential.
Second, we examine another case of CCD which we call Text Cloning. Text
Cloning can occur when running multiple copies of the same binary, Extrinsic
Text Cloning, or when running multiple instances of the same application in
a Virtually Indexed Virtually Tagged cache, Intrinsic Text Cloning. Results
show that both Intrinsic Text Cloning and Extrinsic Text Cloning can reduce
an application's performance. Specifically, Extrinsic Text Cloning causes up
to 11% slowdown on existing platforms. Furthermore, we show that CATCH can
benefit performance by eliminating the duplication due to Intrinsic Text
Cloning and Extrinsic Text Cloning.
Third, we investigate the potential of CCD for L1 data caches. The results
indicate that caches exhibit a high amount of dirty blocks thus making the
CCD detection and creating stable correlations between different blocks very
difficult. If a block is written, all duplicate relations to that block need
to be invalidated. Our analysis also shows that zero runs are very frequent
in L1 data caches and, therefore, previously proposed zero detection
mechanisms can provide good solutions.
Finally, this thesis considers the CCD phenomenon for Last Level Caches. The
LLC caches are written less frequently (L1 data cache acts as a filter) and
have less zero runs because they mostly store evicted cache blocks that have
already written with non-zero values. Results indicate that CCD is very
frequent for various block granularities, from 4bytes up to 64bytes, and has
potential to improve processors performance or save energy. A new cache
design, the Content Duplication Aware Cache, is proposed to detect and
eliminate CCD in LLCs. The results indicate that the Content Duplication
Aware Cache can improve performance moderately but can reduce Energy Delay
product considerably, up to 15% and 10% on average, for multiprogram
workloads.
Short Bio:
Marios Kleanthous is a PhD. Candidate at the Department of Computer Science,
University of Cyprus. He received his BSc. in Informatics and
Telecommunications from National and Kapodistrian University of Athens in
2004 and his MSc. in Computer Science from the University of Cyprus in 2006.
On September 2006 we worked in ARM Ltd in Cambridge for three months during
a HiPEAC funded internship. His research interests include Memory Hierarchy
Optimizations and especially Cache Compression techniques.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Loizos Michael
Affiliation: Open University of Cyprus, Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Thursday, March 22, 2012
Time: 13.30-14.45 EET
Hosts: Christos Schizas (schizas AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2012.michael
Abstract:
If one accepts that the ability to pass the Turing Test is a useful indicator — if not a defining property — of machine intelligence, then one should also accept the importance of endowing machines with the ability to read. But before realizing this goal, one first needs to make more precise what “reading” even means. The task of (Recognizing) Textual Entailment can be seen as capturing a key element of reading: the ability to draw (or at least recognize) inferences from a given piece of text. The original operational definition of the task appeals to human judgment to determine soundness of inference. Such an inherently subjective and anthropocentric definition of the task precludes it, however, from being applicable to machines that acquire the ability to read in an autonomous and highly scalable manner.
This talk discusses a definition for textual entailment that retains the formal objective aspects of logical entailment, yet it embraces the statistical nature of the operational definition, and avoids rigidness. The proposed definition views text as a partial depiction of some underlying hidden reality, mapped into a piece of text through the text’s author. Textual entailment is, then, the task of accurately recovering information about this underlying reality. High performance on this task can be provably (under typical assumptions) achieved by training a machine on a corpus of text relevant to the domain of interest, without the need for human supervision to identify the inferences that are expected to be drawn from each piece of text. Experimental results confirm the applicability of the approach in a real-world setting.
Short Bio:
Loizos Michael is a lecturer at Open University of Cyprus (since 2009). He is the founder and director of the Computational Cognition research lab (since 2010), and the academic head of a graduate program of studies in Information Systems (since 2011). Before joining OUC he held a visiting lecturer position at University of Cyprus (2008–2009). He was educated at University of Cyprus, where he received a B.Sc. in Computer Science with a minor degree in Mathematics (2002). He continued his education at Harvard University, where he received an M.Sc. and a Ph.D. in Computer Science (2003 and 2008, respectively).
His research focuses on the formal and principled understanding of cognitive processes such as learning and reasoning, and how those are employed by humans and other biological organisms in their everyday lives. Specific areas of interest include: commonsense reasoning, temporal and default reasoning, argumentation, computational learning theory, computational evolution theory, computational story understanding, nature-inspired computation, distributed and multi-agent systems.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Seminar entitled:
Speaker: Andreas Pitsillidis
Affiliation: University of California - San Diego, USA
Category: Seminar
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Wednesday, February 29, 2012
Time: 15:00-16:00 EET
Hosts: Andreas Pitsillides (Andreas.Pitsillides AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2012.pitsillides
Abstract:
Much of computer security research today engages a hypothetical adversary: one whose aims and methods are either arbitrary or driven by some pre-supposed model of behavior. However, in many cases, the scope, motivation and technical evolution of actual attacks can be quite different and leads to a model where our research frequently trails the "truth on the ground". At the same time, our present ability to gather, process and analyze data concerning Internet activity is unmatched and thus there are tremendous opportunities in advancing a regime of "data-driven security", wherein our understanding of the adversary, of our vulnerable users and of the efficacy of our current defenses and interventions can be placed on a strong empirical footing. In this talk, we will focus on the spam ecosystem and related threats, and look into the possible defensive intervention levels. We will do so both from the perspective of the attackers, in order to get a solid understanding of how they operate, and also from the perspective of the users. We will also use this analysis as input, for proposing new effective defenses to these threats.
Short Bio:
Andreas Pitsillidis is currently a Ph.D. candidate at the University of California, San Diego. He completed his undergraduate studies at the Department of Computer Science in the University of Cyprus. He was awarded a Fulbright Scholarship and joined UC San Diego in 2007, and received his M.Sc. from the Department of Computer Science and Engineering in 2010. His research interests lie in the general area of computer security, with an emphasis on botnets, spam, phishing and DNS abuse techniques. His most recent work includes collaborations with Microsoft Research, Google and UC Berkeley.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Efi Papatheocharous
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Monday, December 19, 2011
Time: 10:30-11:30 EET
Hosts: George Papadopoulos (george AT cs.ucy.ac.cy) and Andreas Andreou (andreas.andreou@cut.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.papatheocharous
Abstract:
Software cost estimation (SCE) is the art of balancing time and resources to optimally budget a project. An essential requirement is to estimate the schedule, cost and human effort required to complete the project with adequate accuracy before the project commences. Estimates performed at an acceptable (early) point in time during the project life-cycle may be also considered useful to the project.
SCE models proposed within this area of research consist of mathematical algorithms or parametric relations used to approximate the most dominant cost for developing a software product, the human effort, in terms of person-months. Thus SCE is considered one of the basic project management processes to support efficiently the activity of resource allocation. Although numerous SCE models and techniques have been proposed by researchers, recent research reports 60-80% of projects overrun software cost estimates by 30-40%.
The present dissertation proposes models and techniques, based on the factors of People – Process – Product, for improving software cost estimation accuracy and increasing comprehensibility over the risks occurring. Moreover, the essential factors that affect productivity are identified and explored. Particularly, this diatribe adopts two approaches: A quantitative and a qualitative. The quantitative approach, aims at improving SCE accuracy, reliability and generalisability, by exploring Computational Intelligent (CI) models and techniques, such as Artificial Neural Networks (ANN), Evolutionary Algorithms (EA), Fuzzy Logic (FL), and hybrid forms of the aforementioned techniques. Moreover, the main target is to develop SCE models of a practical value, i.e., dealing with the inherent uncertainty of the software engineering data and producing relatively ‘early’ (i.e., post specifications) estimations. The qualitative approach extends the numerical and empirical CI investigations, by employing Fuzzy Cognitive Maps (FCM) and Influence Diagrams (ID), which facilitate the exploration of the relationships between qualitative (‘soft’) cost factors and effort. It also visually reveals the contribution of attributes in SCE and enhances our understanding of the cause-and-effect dependencies.
The results and observations obtained from the experimental studies of this dissertation reveal that considerable benefits are gained by CI-based methods employed in cost prediction improvement and in understanding which factors are more significant or influential in the process of SCE. A variety of Feature Subset Selection (FSS) methods are applied that facilitate in identifying and excluding the less influential cost factors from the models, which, in turn, lower the overall time and effort required to measure, collect and maintain these factors. The SCE models proposed in this thesis are proven viable, practical alternatives through extensive experimentation with widely known and used benchmark data obtained from the relevant literature.
Short Bio:
Efi Papatheocharous is a PhD Candidate and Research Associate at the Department of Computer Science at the University of Cyprus, where she carries out research and studies primarily in the area of Software Engineering with specific research interests in Computational Intelligence and Software Cost Estimation. After graduating from the University of Manchester with an MSc degree in Advanced Computer Science with Information Communication Technologies Management from the Computer Science Department, in December 2005, and after attaining an undergraduate BSc in Computer Science from the Computer Science Department at the University of Cyprus, in June 2004, she has been collaborating in a number of research projects at a National and European level and has co-authored several papers presented in International Conferences, published in peer reviewed books and scientific journals.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Seminar entitled:
Speakers: Michalis Agathocleous and Petros Kountouris
Affiliation: University of Cyprus, Cyprus
Category: Seminar
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Thursday, 24 November 2011
Time: 16:30-17:30 EET
Hosts: Chris Christodoulou (cchrist AT ucy.ac.cy) and Vasilis Promponas (vprobon AT ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.agathocleous
Abstract:
Protein secondary structure prediction (PSSP) is a critical step towards modelling protein 3D structure and, potentially, protein function. Over the past 20 years, machine learning techniques and evolutionary information have significantly boosted the quality of PSSP methods. However, there is still an opportunity for more accurate prediction through the use of more sophisticated learning algorithms. The Bidirectional Recurrent Neural Network (BRNN) architecture of Baldi et al. [Baldi et al., Bioinform., 15, 937-946, 1999] is currently considered as one of the most optimal computational neural network type architectures for addressing the problem. In this project, we have implemented the same BRNN architecture, but we have used a modified training procedure [Agathocleous et al., IFIP International Federation for Information Processing AICT, 339, 128-137, 2010]. More specifically, our aim is to identify the effect of the contribution of local versus global information, by varying the length of the segment on which the Recurrent Neural Networks operate for each residue position considered. For training the network, the backpropagation learning algorithm with an online training procedure is used, where the weight updates occur for every amino acid, as opposed to Baldi et al., where the weight updates are applied after the presentation of the entire protein sequence. The performance of our method improved even further through the use of an ensemble of BRNNs. In addition, we have developed and implemented the Scaled Conjugate Gradient optimization algorithm to train the BRNN architecture.
Additionally, our work focuses on the challenging problem of filtering PSSP, a common final step in many PSSP methods which aims to smooth the results and provide physicochemically realistic predictions [Kountouris et al., IEEE/ACM Trans. on Comput. Biol. and Bioinform., submitted, 2011]. Despite being employed widely, to the best of our knowledge, no study has been carried out to find the most suitable filtering technique. Herein, we perform a comparative study on the challenging problem of filtering, utilising both empirical smoothing rules and machine learning techniques.
Short Bio:
Michalis Agathocleous received a B.Sc. degree (with distinction) in Computer Science from the University of Cyprus, Nicosia, Cyprus, in 2009, and a M.Sc. degree in Machine Learning, from the University College London (UCL), London, U.K., in 2010. He is currently pursuing a Ph.D. degree at the Department of Computer Science, University of Cyprus. His current research interests include bioinformatics, neuroscience, machine learning and computational intelligence.
Petros Kountouris initially obtained a B.Sc. in Computer Engineering and
Informatics from the University of Patras, Greece, in 2006. He later moved
to the UK where he received a Ph.D. in Chemistry/Bioinformatics from the
University of Nottingham in 2010. He is currently working as a post-doctoral
researcher at the Department of Computer Science in the University of
Cyprus, Cyprus. He has continuous interest for structural computational
biology and on possible applications of computational intelligence and
machine learning to bioinformatics.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Samer Arandi
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Thursday, November 17, 2011
Time: 10:00-11:00 EET
Host: Paraskevas Evripidou (skevos AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.arandi
Abstract:
Since the advent of digital computers, chip designers built faster computers by relying on improvements in fabrication technologies and architectural/organizational optimizations. However, the inability of the sequential model to tolerate long latencies (manifested mainly in the Memory Wall) combined with the Power and Instruction Level Parallelism (ILP) Walls problems eventually rendered this approach ineffective. The envisaged solution was to switch to multi-core architectures. This switch was an engineering effort that did not address the long memory latencies and the complexity of the designs. In addition, this switch elevated concurrency as a major challenge as it became evident that new concurrent models/paradigms are needed to efficiently utilize the resources of multi-core chips.
The Data-flow model is a formal model that can handle concurrency and tolerate memory and synchronization latencies. Data-Flow systems can also be simpler and so more power efficient than conventional systems.
In this thesis, we propose re-visiting the Data-flow model and adopting it as the basis for an execution model that efficiently exploits the resources of multi-core architectures. We design and implement a virtual machine supporting the Data-Driven Multithreading (DDM) model of execution (which combines Dynamic Data-Flow concurrency with efficient sequential execution) on homogeneous and heterogeneous multi-core systems with a host/accelerator organization and a software-managed memory hierarchy. A special prefetching software cache -based on data-driven caching policies- is developed for the automatic management of such memory hierarchies. The developed virtual machine also supports distributed DDM execution on a cluster of multi-core nodes connected over an off-chip network.
We evaluate the homogeneous and heterogeneous implementations of the VM for single multi-core nodes and clusters of nodes using a suite of benchmarks. The evaluation demonstrates that the VM scales well and tolerates latencies and synchronization overheads efficiently achieving very good performance and outperforming other state-of-the-art systems. The results indicate that the virtual machine efficiently exploits data-flow concurrency on conventional/commercial multi-core systems, which strengthens the case that hybrid models that combine Data-Flow concurrency with efficient control-flow execution are candidates for adoption as the basis of a new execution model for Multi core systems.
Short Bio:
Samer Arandi is a PhD. Candidate at the Department of Computer Science, University of Cyprus. He received his BSc. in Computer Engineering from An-Najah University in Palestine in 2004 and his MSc. in Advance Computing with distinction from the Imperial College - UK in 2006. His research interests include Data-flow and Parallel Architectures and Multi-core Systems.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Seminar entitled:
Speaker: Panayiotis Kolios
Affiliation: King’s College London, UK
Category: Seminar
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Wednesday, Oct 19, 2011
Time: 13:00-14:00 EET
Host: Andreas Pitsillides (Andreas.Pitsillides AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.kolios
Abstract:
It is without doubt that mobile Internet can be considered as one of the most disruptive technologies of our times. The ease of access to information anywhere and at any time proves to be an invaluable proposition that gains increasing popularity. Current figures make it hard to argue otherwise, with mobile Internet access observing an exponential growth in demand over the last few years. However, such a demand growth has exacerbated the energy inefficiencies in operation and in turn significantly deteriorated system performance. From the mobile terminals point of view, the extended usage has shortened the recharging cycles constraining in effect true mobility. At the network access side, the increase in utilization has significantly raised the energy bill and stigmatized the telecoms sector with a substantial contribution to the total CO2 emissions on the planet. As such, energy efficiency is currently considered as one of the most prominent problems to address in order to ensure the sustainable proliferation of current and future communication systems.
This talk will provide an in-depth analysis of the energy consumption profile of networking devices (including both handsets and access network equipment) and further elaborate on the various different ways of achieving higher energy efficiency gains during operation. The talk will then concentrate on the opportunities offered by mobile Internet (as opposed to simple voice services) and detail mechanical relaying schemes that promise to achieve substantial reductions in energy consumption while improving the overall operation of the system.
Short Bio:
Panayiotis Kolios is a PhD candidate at the Centre of Telecommunications Research, King’s College London. His research interests lie broadly within the area of wired/wireless networks and more specifically on optimization techniques for multimedia and mobile Internet communications. For his PhD thesis, energy efficiency aspects for cellular networks have been investigated and green networking solutions have been proposed. The latter research has been funded by the EPSRC Doctoral Training Account (DTA) studentship and the research outcomes have been explored within the “Green Radio” program of the Virtual Centre of Excellence in Mobile and Personal Communications (MVCE) in the U.K.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Seminar entitled:
Speaker: Dr. Nicolas Nicolaou
Affiliation: University of Cyprus, Cyprus
Category: Seminar
Location: Room 146, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Tuesday, September 13, 2011
Time: 18:00-19:00 EET
Host: Chryssis Georgiou (chryssis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.nicolaou
Abstract:
In this work we explore the communication and computation costs of multiple-writer multiple-reader (MWMR) atomic read/write register implementations in asynchronous message-passing systems with crash-prone processors. We consider algorithms that use quorum systems, collections of subsets of replica hosts with pairwise intersection, called quorums. A quorum system has intersection degree n (also called n-wise quorum system), if every n quorum members of this system have a non-empty intersection.
We introduce a new technique we call server side ordering (SSO), that transfers partial responsibility of the ordering of write operations to the replica hosts. Using this idea we design algorithm SFW that uses n-wise quorum systems and relies on predicates to allow fast read and write operations. The algorithm uses tag-value pairs to order the write operations and combines a global ordering imposed by the servers with a local ordering established by each writer participant.
We formulate a new combinatorial problem that captures the computational burden of evaluating the predicates in algorithm SFW and we show that it is NP-Complete. To make the evaluation of the predicates feasible, we present a polynomial log-approximation algorithm for this problem and we show how to use it with algorithm SFW.
We then identify that SFW allows fast operations under restrictions on the construction of the underlying quorum system. So we design an algorithm that allows some single round reads but trades the speed of write operations for removing any constraints on the quorum system construction. The new algorithm, called CwFr, incorporates Quorum Views, algorithmic techniques presented in the SWMR model to enable fast read operations.
Lastly we implement our algorithms in the single-processor simulator, NS2, and on the planetary-scale network platform Planetlab. NS2 helped us evaluate our algorithms under a fully controlled environment, whereas Planetlab helped the evaluation of the algorithms on real-time network infrastructures. In this talk we will present a set of representative plots that illustrate the performance of the proposed algorithms in both environments.
Notice:The presentation is part of the final dissemination seminar of the Research Promotion Foundation funded Project ΠΕΝΕΚ/0609/31.
Refreshments will be served!
Short Bio:
Dr. Nicolas Nicolaou received his BSc from the Computer Science Department at the University of Cyprus in 2003 and he obtained an MSc (2006) and a Ph.D. (2011) from the Computer Science and Engineering Department at the University of Connecticut. His research interests focus in analysis, design and implementation of practical and robust distributed and parallel algorithms, algorithms in ad-hoc mobile and sensor networks and evaluation and security of voting technologies. His PhD research has been partially funded by the Cyprus Research Promotion Foundation and co-funded by the Republic of Cyprus and the European Regional Development Fund under the project ΠΕΝΕΚ/0609/31. As of September 2011, Nicolas Nicolaou will be a Visiting Lecturer at the Department of Computer Science at the University of Cyprus.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Marinos Georgiades
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, August 23, 2011
Time: 09:00-10:00 EET
Host: Constantinos Pattichis and Andreas Andreou (pattichi | aandreou AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.georgiades
Abstract:
Effective implementation of an Information System requires a formal, understandable and time-saving requirements engineering (RE) methodology. Current approaches in RE fail to provide a specific, easily understood formalization of the major parts of the stages of requirements discovery, analysis and specification, and they usually result to a requirements document with ambiguities, redundancies and inconsistencies.
The present dissertation introduces Natural Language Syntax and Semantics Requirements Engineering (NLSSRE), a compact and clear-cut methodology that is intended to formalize and automate a large part of the RE process, including discovery, analysis and specification of user requirements for the development of Information Systems, utilizing syntactic and semantic concepts of natural language (NL). NLSSRE is designed so that the analyst is guided in advance, through a step-by-step approach, what specific types of data, functions, business rules and functional conditions to use and search for, what questions to ask, in what specific way to analyze the answers to these questions and how to document them using formalized sentential requirement patterns. The formalized requirements are then easily transformed, with the use of specific rules, into diagrammatic notations, including class diagrams, data flow diagrams and use-case diagrams, as well as use-case and textual specifications, the latter following a certain Software Requirements Specifications (SRS) template. The formalization provided by NLSSRE is achieved with the aid of Natural Language elements, such as verbs, nouns, genitive case, adjectives and adverbials, while its automation is realized through the use of a dedicated CASE tool.
To evaluate the effectiveness and efficiency of the proposed methodology, an experimental study was performed through which the NLSSRE methodology was compared to the classical Object-Oriented RE approach, by applying both of them in a real-life setting. The results were quite encouraging indicating that NLSSRE performed much better than the classical approach, as assessed by various objective quality metrics, such as completeness, correctness, modifiability and prioritization. The difference between the two approaches was also significant in regard to efficiency, where NLSSRE performed much faster than the classical one.
Short Bio:
Marinos Georgiades is a Ph.D. Candidate at the Department of Computer Science, University of Cyprus. He received his master’s in Information Management and bachelor’s in Computer Science, from the University of Sheffield in 2001 and the University of Cyprus in 2000, respectively. His research interests include Software Engineering and more specifically Requirements Engineering with emphasis on the use of Natural Language for the formalization and automation of software requirements elicitation, analysis and specification.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Presentation entitled:
Speaker: Dr. Odysseas Papapetrou
Affiliation: Technical University of Crete, Greece
Category: Presentation
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, June 28, 2011
Time: 11:30-12:00 EET
Host: George Samaras (cssamara AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.papapetrou
Abstract:
Many problems of distributed computing can be reduced to monitoring the
value of a function defined over a set of distributed data streams with
respect to a threshold. Precisely, given an arbitrary (not necessarily
linear) function, a threshold, and a set of distributed data streams out
of which the input of the function is determined, we want to detect the
event of the function value crossing the threshold. The state-of-the-art
approach for function monitoring relies on geometric insights to
decompose the monitoring process to a set of local constraints for each
stream. In this talk, I will present this approach and summarize our
ongoing work based on it.
Short Bio:
Odysseas Papapetrou is currently a postdoctoral researcher at the Technical University of Crete, working on P2P networks and distributed streams. He received his PhD in Computer Science from University of Hannover, while collaborating with the L3S Research Center. He also obtained an M.Sc. from Saarland University in Germany, supported by an IMPRS scholarship, and a B.Sc. and M.Sc. from the University of Cyprus.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Presentation entitled:
Speaker: Dr. Ekaterini Ioannou
Affiliation: Technical University of Crete, Greece
Category: Presentation
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, June 28, 2011
Time: 11:00-11:30 EET
Host: George Samaras (cssamara AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.ioannou
Abstract:
Entity linkage is central to almost every data integration and
data cleaning scenario. Traditional techniques use some computed
similarity among data structure to perform merges and then answer
queries on the merged data. The presentation will introduce a
mechanism for entity linkage with uncertainty. Instead of performing
the merges based on the linkages, it stores the entity linkages
alongside the data and performs only the required merges at run-time,
by effectively taking into consideration the query specifications.
Short Bio:
Ekaterini Ioannou obtained a B.Sc. and an M.Sc. from University of Cyprus, an M.Sc. from Saarland University and the Max-Planck-Institut für Informatik, and a Ph.D. from the Leibniz Universität Hannover and the L3S Research Center in Hannover, Germany. Currently, she is a postdoctoral researcher at the Technical University of Crete, working on entity linkage for heterogeneous data with uncertainties and management of uncertain data using statistical models.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Panayiotis G. Andreou
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Monday, May 23th, 2011
Time: 16:00-17:00 EET
Host: George Samaras and Demetris Zeinalipour (cssamara | dzeina AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.andreou
Abstract:
Wireless Sensor Networks (WSNs) offer a non-intrusive technology that enables users to monitor the physical world at an extremely high fidelity. In order to collect the data generated by these tiny-scale devices, the data management community has proposed the utilization of declarative data-acquisition frameworks. While these frameworks have facilitated the energy-efficient retrieval of data from the physical environment, they were agnostic of the underlying network topology and also did not support advanced query processing semantics.
In this dissertation we present KSpot+, a novel distributed network-aware framework for WSNs that optimizes network efficiency by combining three novel components: i) the Tree Balancing Module, which balances the workload incurred on each sensor node during a query by constructing efficient network topologies; ii) the Workload Balancing Module, which minimizes data reception inefficiencies by synchronizing the network activity intervals of each sensor node; and iii) the Query Processing Module, which provides advanced query processing semantics by employing a novel ranking mechanism that yields only the k-highest ranked answers, thus further minimizing energy consumption. The modules of the KSpot+ framework can operate both in isolation and in combination with each other, offering high degrees of energy efficiency, scalability and accuracy in the presence of failures.
In order to validate the efficiency of our approach, we have created a prototype implementation of the KSpot+ framework in nesC and JAVA. In our experimental evaluation, we thoroughly assess the performance of KSpot+ using the real prototype system we developed and datasets from the University of California - Berkeley, the University of Washington and Intel Research Berkeley. We show that KSpot+ provides significant energy reductions under a variety of conditions, thus prolonging the longevity of a WSN as much as 317%, compared to predominant approaches.
Short Bio:
Panayiotis G. Andreou is a PhD Candidate at the Department of Computer Science, University of Cyprus.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Andreas Panayides
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Friday, May 20th, 2011
Time: 15:00-16:00 EET
Host: Constantinos Pattichis (pattichi AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.panayides
Abstract:
A new framework for effective communication and evaluation of wireless medical video over error-prone channels is proposed. Motivated by the need to efficiently address unique requirements associated with medical video source encoding, wireless transmission, and quality assessment, a unified framework which addresses individual requirement is developed. The envisioned utilization scenarios target remote diagnosis and care and emergency situations.
The approach is based on a spatially varying encoding scheme, where video slice quantization parameters are varied as a function of diagnostic significance. Video slices are automatically set based on a segmentation algorithm. They are then encoded using a modified version of H.264/AVC Flexible Macroblock Ordering (FMO) technique that allows variable quality slice encoding and Redundant Slices (RS) for resilience over error prone transmission mediums.
Evaluation of the proposed scheme is performed on a representative collection of ten (10) ultrasound videos, nine of the carotid and one of the femoral arteries, for packet loss rates up to 30%. Extensive simulations incorporating three FMO encoding methods, different quantization levels and display resolutions, and different packet loss scenarios are investigated. Quality assessment is based on a new clinical rating system that provides for independent evaluations of the different parts of the video (subjective). Objective video quality assessment metrics are also employed and their correlation to the clinical quality assessment of plaque type is derived. To this end, some objective quality assessment measures computed over the plaque video slices gave very good correlations to Mean Opinion Scores (MOS). Here, MOS were computed using two medical experts.
Experimental results show that the proposed method achieves enhanced performance in noisy environments, while at the same time achieving significant bandwidth demands reductions, providing for transmission over 3G (and beyond) wireless networks. The proposed unified framework can be applied with minor modifications to other medical modalities.
Short Bio:
Andreas Panayides is a PhD candidate in the Computer Science Department of the University of Cyprus. He received the B.Sc. degree from the department of Informatics and Telecommunications of the National and Kapodistrian University of Athens in 2004, and the M.Sc. degree in Computing and Internet Systems from KINGS College in 2005. His research interests include video processing and communications, eHealth applications, and mobile telecommunication networks. His PhD funding came from the project “Real-Time Wireless Transmission of Medical Ultrasound Video” funded by the Research Promotion Foundation (RPF) of Cyprus and the European Regional Development Fund (ERDF). He has been a research associate at the department of Computer Science of University of Cyprus since 2006, where he has been involved in IST-funded project C-MOBILE and RPF-funded project MARTE-III.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Athos Antoniades
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Friday, May 20th, 2011
Time: 09:00-10:00 EET
Host: Constantinos Pattichis (pattichi AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.antoniades
Abstract:
Most common diseases have a heritable component that is influenced by
mutations on multiple loci, and by interactions between loci and with
the environment. However, traditional genetic analyses techniques have
focused on single locus effects. This is mostly due to the polynomial
increase in computational capacity needed to attempt multi-loci
interaction analyses, and the anticipated loss of power due to
multiple testing. In this dissertation, a framework for performing a
complete two SNP interaction analysis of high dimensionality genome
wide association scans (GWAS) is presented. The implementation of the
framework utilizes diverse distributed computational resources to
overcome the bottlenecks of each resource, harvesting enough capacity
to analyze any of the GWAS in existence today within a reasonable time
frame. Algorithmic approaches are proposed to improve the efficiency
of the framework and improve its computational performance so that a
brute force attack on the problem can be performed. The data is
encoded in binary using a lossless algorithm that significantly
reduces its size. Computationally efficient data mining measures for
the Omnibus and Epistatic interaction effects are proposed and
compared to traditional statistical techniques. An algorithm is
proposed that optimizes the analyses of multiple response variables
within the same GWAS. GenMSA, a multiple sclerosis (MS) dataset, is
analyzed using the proposed framework with top results tested for
replication using ANZgene, an independent MS dataset. Some of the top
results replicated, implicating SNPs in a region of known association
to MS providing evidence to the validity of the proposed framework.
Top results are further examined through a proposed approach that
enables drilling into these results and studying correlation
coefficient between each of the genotype combinations of the SNP and
the signal level to each of the main and epistatic effects.
Short Bio:
Antoniades Athos is a doctoral student in the Computer Science
Department of the University of Cyprus. He has previously obtained a
MSc in Computer Science from the St. Cloud State University in
Minessota USA (SCSU). He has also worked as a full time scientist as
the Research and Development department of pharmaceutical company
Glaxo Smith Kline where he maintains an active colaboration. His
research interests lie within the broad area of computational biology
and bioinformatics with special interest in computational genetics and
applications of data mining, computational intelligence and signal
processing applied to problems in the medical domain.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Kleanthis C. Neokleous
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Friday, May 13th, 2011
Time: 13:00-14:00 EET
Host: Christos Schizas (schizas AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.neokleous
Abstract:
A nerocomputational model of visual selective attention was implemented in the MATLAB/SIMULINK environment and was used to account for a variety of empirical findings in the field of attention. The model is based on what is currently known about the neural basis of attention and involves two stages of processing realized as spiking neural networks (SNN). The first stage simulates the initial bottom-up competitive neural interactions among visual stimuli, while the second stage involves modulations of neural activity based on the semantic properties of the stimuli. During the progression of the neural activity in the two stages of processing, the encoded stimuli compete for access to working memory (WM) through forward, and lateral inhibitory interactions, which influence the strength of their neural response. At the same time, top down interactions may influence the overall processing in both stages.
The basic functionality of the model relies on the assumption that an incoming visual stimulus is processed based on the rate and temporal coding of its associated neural activity. Thus, a saliency map algorithm is used in the model to set neural activity at the early stages of processing. In the second stage of processing, neural activity passes through a correlation control system comprised of coincidence detector neurons. These neurons measure the degree of semantic correlation between endogenous goals and the neural representation of the visual stimuli and may increase the synchronization between the brain areas involved in vision and goal maintenance.
The developed model was used to simulate the findings from several behavioral experiments on the Attentional-Blink Phenomenon, the Perceptual Load theory of attention, and the relation between attention and consciousness.
Short Bio:
Kleanthis Neokleous is a doctoral student in the Computer Science Department of the University of Cyprus. He has previously obtained a BA and MSc in Mechanical Engineering from the National Technical University of Athens (NTUA) as well as a double MSc in Space science and technology from the Lulea University of Technology – Sweden and MSc in Space Systems and Automation from the Czech Technical University – Czech Republic. His research interests lie within the broad area of computational neuroscience, mainly through cognitive modeling. Furthermore he has been involved with various applications based on computational intelligence methods. Currently he is working as a graduate research assistant on a project dedicated to the study of visual selective attention.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Christophoros Christophorou
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, April 19th, 2011
Time: 10:00-11:00 EET
Host: Constantinos Pattichis (pattichi AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.christophorou
Abstract:
The introduction in wireless networks of multimedia services such as streaming video, mobile TV and others, increased the need for communication between one sender and many receivers, leading to the need of Point-to-Multipoint transmission, achieved mainly through the use of multicasting technologies. A first successful attempt to provide efficiently multimedia services in wireless mobile networks came with the introduction of MBMS (Multimedia Broadcast Multicast Service) system in UMTS (Universal Mobile Telecommunications System) Release 6 specifications. MBMS system is considered as one of the most important steps of the UMTS Network evolution since it provided it with a powerful tool to offer broadcast and multicast services efficiently, with the main benefit of major core- and radio- resource savings. Within the 3GPP standards group there is still a lot of ongoing work to define the appropriate standards for MBMS. Although the service and technical requirements are complete, still many design issues need to be considered for MBMS services to be provided in a more efficient way, especially in the UTRAN (UMTS Terrestrial Radio Access Network) part where the radio resources are limited. Adopting the Radio Resource Management (RRM) algorithms currently specified in the 3GPP documents to provide MBMS services, more than 30% of the Node-B’s total power has to be allocated to a single 64 Kbps MBMS service in order to cover the whole cell. This can make MBMS services too expensive since the overall UMTS network capacity is limited by the Node-B’s power source. Thus, in order to make MBMS services feasible and also attractable to the consumers, challenges are raised for more efficient RRM algorithms to be introduced. Therefore, during this Ph.D. dissertation we deal with this issue and investigated and proposed efficient, scalable and effective RRM algorithms controlling parameters such as handover criteria, transmit power and channel allocation, facilitating decisions targeting seamless handovers, increased network capacity and overall system performance (and thus achieve lower service costs) as well as acceptably good QoS for the users during the MBMS service provision in UTRAN.
Short Bio:
Christophoros Christophorou is a PhD candidate in Computer Science of the University of Cyprus.
He has completed his undergraduate and graduate studies at the University of Cyprus (B.Sc. in Computer Science and M.Sc. in Advanced Computer Technologies, 2002 and 2005, respectively). He is currently working at the University of Cyprus in the area of wireless mobile networks. He has been a research associate at the department of Computer Science of University of Cyprus since April 2004, where he has been involved in the IST funded B-BONE, MOTIVE and C-MOBILE projects and ICT funded C-CAST project. His research interests include Radio Resource Management in 3G and beyond mobile Cellular Networks, specifically capacity and performance enhancements through dynamic and adaptive radio resource allocation and handover algorithms.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Theodosis Theodosiou
Affiliation: Microsoft, Cyprus
Category: Invited Course Lecture
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, Mar. 29th, 2011
Time: 17:00-19:30 EET
Host: Nikolas Stylianides (nstyl AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.theodosiou
Abstract:
This talk will cover the following topics:
- Cloud computing and Microsoft Strategy
- Benefits of Cloud
- The Evolution of the Datacenter
- Private Cloud, IaaS, PaaS and SaaS
- Cloud and on-Premise co-existanse
- Office 365
Short Bio:
Theodosis Theodosiou (Account Technology Strategist), has been working in Microsoft for 4 years initially at the role of Technology Solution Specialist and then moved to the Account Technology Strategist. The Account Technology Strategist (ATS) adds value to Microsoft by providing technical guidance to customers, resulting in expanded deployments of Microsoft technology, in targeted Enterprise accounts.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Stuart Mackenzie
Affiliation: FMT
Category: Invited Course Lecture
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, Mar. 22nd, 2011
Time: 17:00-19:30 EET
Host: Nikolas Stylianides (nstyl AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.stuart
Abstract:
One of the major challenges facing global banks is how to improve the online experience of its customers using its unauthenticated website. This is the online store front for the bank but it is much more difficult to tailor the users experience due to the fact that you are dealing with an anonymous user. This is a presentation giving an example as to how this recurring problem is now being addressed as a best practice in the IT profession via "Application Mediation"
This is the second in a series of UCY lectures discussing the role of Application Mediation.
Introducing Application Mediation: 24.11.2010
Short Bio:
Stuart Mackenzie is responsible for the strategy, development and
implementation of FMT strategic alliances and rapid business growth.
Stuart previously managed multiple vendor and partner relationships
to drive secure e-business enablement across developed and
developing markets as part of GE Money's Global Fraud Management
team.
Before that, he served as Remote Channel Fraud Strategy and Policy
Manager at Barclays Bank where he pioneered anti-fraud solutions in
response to the emergence of phishing and delivered 3D Secure
technology to Barclaycard's credit and debit card portfolios. Stuart is
a former member of APACS' E-Banking Fraud Liaison Group (the UK's
Association for Payment and Clearing Services) and won the 2005
Anti-Fraud Strategy of the Year honor at the UK's Finance Sector
Technology Awards.
Stuart is based in Limassol, Cyprus since 2008
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Michael Georgiou
Affiliation: National Bank of Greece, Cyprus
Category: Invited Course Lecture
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Friday, Mar. 18th, 2011
Time: 18:00-19:30 EET
Host: Nikolas Stylianides (nstyl AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.georgiou2
Abstract:
This talk will cover the following topics:
1. RAC Presentation Overview
2. Recognize the various components of CRS and RAC
3. Use the various types of files in a RAC database
4. Share database files across a cluster
5. Use services with RAC
6. Installing 2-nodes RAC on Oracle Virtual Box (Guidelines)
Short Bio:
Michael Georgiou currently works at the National Bank of Greece (Cyprus Branch) as an Oracle Database and Oracle Application Server Administrator. He earned an M.Sc. degree in Computer Science from the University of Cyprus (2011) and Bsc degree in Computer Science from Cyprus College (2004). He is Oracle Certified Professional (OCP) and Red-Hat Certified Engineer (RHCE). He has 8 Years of experience with Oracle Database and Oracle Applications Servers Administration and Instruction. He works on large government projects such as the Police Computerization System, Cyprus Social Insurance, Ministry of Labor and others. Mr Michael specializes in application analysis and development (PL/SQL,Java,C,C++). In the past he has worked for NetU Consultant ltd (2004-2007).
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Michael Georgiou
Affiliation: National Bank of Greece, Cyprus
Category: Invited Course Lecture
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Friday, Mar. 11th, 2011
Time: 18:00-19:30 EET
Host: Nikolas Stylianides (nstyl AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.georgiou1
Abstract:
This talk will cover the following topics:
1. Explain database files: datafiles, control files, online redo logs
2. Explain SGA memory structures: Database Buffer Cache, Shared Pool, and Redo Log Buffer
3. Explain primary background processes:DBWn, LGWR, CKPT, PMON, SMON
4. Explain the use of the background process ARCn
5. Identify optional and conditional background processes
6. Explain logical hierarchy
7. Create and manage initialization parameter files
8. Start up and shut down an instance
9. Monitor and use diagnostic files
Short Bio:
Michael Georgiou currently works at the National Bank of Greece (Cyprus Branch) as an Oracle Database and Oracle Application Server Administrator. He earned an M.Sc. degree in Computer Science from the University of Cyprus (2011) and Bsc degree in Computer Science from Cyprus College (2004). He is Oracle Certified Professional (OCP) and Red-Hat Certified Engineer (RHCE). He has 8 Years of experience with Oracle Database and Oracle Applications Servers Administration and Instruction. He works on large government projects such as the Police Computerization System, Cyprus Social Insurance, Ministry of Labor and others. Mr Michael specializes in application analysis and development (PL/SQL,Java,C,C++). In the past he has worked for NetU Consultant ltd (2004-2007).
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Prof. Andreas Pitsillides
Affiliation: University of Cyprus, Cyprus
Category: Invited Course Lecture
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, Mar. 8th, 2011
Time: 17:00-19:30 EET
Host: Nikolas Stylianides (nstyl AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.pitsillides
Abstract:Sensors and wireless sensor networks are being deployed around the world, capable of measuring with high precision the local environmental conditions. Their sensing functionality potentially can enable context-aware ubiquitous platforms, middleware and applications to proliferate. Residences can be transformed into smart homes, incorporating embedded sensors and ubiquitous technology. In recent years, new technologies like short-range wireless communications and real-time localization are slowly becoming common, allowing the Internet to penetrate into the real world of physical objects. Inspired from embedded Internet connectivity, the Web of Things (WoT) is about reusing well-accepted and understood Web principles to interconnect the quickly expanding ecosystem of embedded devices, built into everyday smart things. In this talk, we identify contributions that have enabled the vision of Web-enabling smart objects. We will present promising applications of the WoT in domains such as smart homes, urban environments, logistics and the forthcoming smart grid of electricity. We will also discuss and identify challenges in this domain, and how the WoT can constitute a driver towards an energy-efficient, sustainable future.
Short Bio:
Andreas is a Professor in the Department of Computer Science, University of Cyprus, and heads the Networks Research Laboratory (NetRL, http://www.NetRL.cs.ucy.ac.cy). His research interests include fixed and wireless Networks (ad-hock and sensor networks, VANETS, WLANs&WMANs, UMTS Third Generation mobile networks and beyond, 4G), flow and congestion control, resource allocation and radio resource management, and Internet technologies and their application in Mobile e-Services, e.g. in Tele-Healthcare, and the Web of Things. He has a particular interest in adapting tools from various fields of applied mathematics such as adaptive non-linear control theory, computational intelligence, and recently nature inspired techniques, to solve problems in communication networks. Andreas has published well over 200 research papers and book chapters, he is the co-editor with Petros Ioannou of the book on Modelling and Control of Complex Systems (CRC, 2007), participated in over 30 European Commission and locally funded research projects with over 4 million Euro as principal or co-principal investigator, presented invited lectures at major research organisations and universities, has given short courses at international conferences and short courses to industry. Andreas serves/served on the executive committees of major conferences, as e.g. ICT 2011, INFOCOM 2001, 2002, 2003, WiOpt 2007, ISYC 2006, MCCS 2005, and ICT 1998. He is a member of the International Federation of Automatic Control (IFAC) Technical Committee TC 1.5 on Networked Systems and TC 7.3 on Transportation Systems, and of the International Federation of Information Processing (IFIP) working group WG 6.3: Performance of Communications Systems. Andreas is also a member of the Editorial Board of Computer Networks (COMNET) Journal and the International Journal of Handheld Computing Research (IJHCR).
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Panayiotis A. Michael
Affiliation: Cyprus Investment Promotion Agency
Category: Invited Course Lecture
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Wednesday, Mar. 2nd, 2011
Time: 16:30-18:30 EET
Host: Nikolas Stylianides (nstyl AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.pamichael
Abstract:
The presentation will provide an overview of the strategic study for the ICT sector of the Cyprus Investment Promotion Agency (CIPA) (http://www.cipa.org.cy). The presentation will also focus on the recent collaboration between CIPA and the Network of Cyprus Universities
for the attraction and retention of Foreign Direct Investment in R&D projects in Cyprus Academia,
as also on the strategic alignment of CIPA’s ICT strategy with the “Digital Strategy of Cyprus”
of the Department of Electronic Communications – Ministry of Communications and Works (http://www.mcw.gov.cy/mcw/dec/dec.nsf)
with the strong support of the Technology Service of the Ministry of Commerce, Industry and Tourism (http://www.mcit.gov.cy/mcit/mcit.nsf/dmltech_en/dmltech_en?OpenDocument).
The result of this strategic alignment is the development of a joint strategic action for the
creation of a Smart City in Cyprus. Based on CIPA’s intelligence gathering and research,
an equivalent project which was recently launched in Malta, the project Smart City Malta,
aims to create 5600 jobs with emphasis on the ICT sector and to contribute to the Maltese
Gross Domestic Product approximately 534 million euros on an annual basis
(approx. 5%-7% of Maltese GDP).
The presenter will analyze the important role Cyprus Academia can play to the proposed strategic
action Smart City Cyprus, by acting as a pole of attraction and retention of Foreign Direct
Investment in a sustainable manner, and by developing and licensing ICT technologies to
Multi-National Corporations with subsidiaries in Smart City Cyprus, in order for Cyprus
to actively participate in the ICT global value chain.
Short Bio:
Mr. Panayiotis Adamos Michael, holds an M.B.A. from the University of California Los Angeles
with business interests in Strategic Marketing for High-Technology, a M.Sc. in Computer Science from the
same University and a B.Sc. in Electrical Eng. from the National Technical University of Athens. He is a Doctoral
Candidate in Computer Science at UCLA and scientific author and architect of the Streamonas
Data Stream Management System, the only system up to the moment able to reach the maximum level of
difficulty, on a single CPU, of the Linear Road Benchmark designed by M.I.T.
Mr. Michael is a Senior Officer at the Cyprus Investment Promotion Agency (http://www.cipa.org.cy/)
supervising the Strategic Planning, Policy and Intelligence Unit of the Organisation. Mr. Michael has the
responsibility for the execution of the Organisation’s strategy of the ICT sector. His initiative for developing
the Academic Capacities of Cyprus in order to attract Foreign Direct Investment in the country, was inspired by
respective literature of the United Nations Conference on Trade And Development (UNCTAD) and it was
enthusiastically supported by the network of Industry-University liaison offices of the
Universities in Cyprus as also from Computer Science Departments of major Universities in the country.
His efforts are architected based on the experience he received by working closely with his M.B.A.
advisor Prof. Hans Schollhammer on similar, mature frameworks in California.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Panayiotis Ioannides
Affiliation: Cyprus Telecommunications Authority, Cyprus
Category: Invited Course Lecture
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Friday, Feb. 18th, 2011
Time: 18:00-19:30 EET
Host: Nikolas Stylianides (nstyl AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.ioannidis
Abstract:
Cyprus Telecommunications Authority (CYTA) is the dominant telecommunication service provider in Cyprus and provides a wide range of telecommunications services. It offers fixed and mobile communications for both voice and data, Value Added Services (VAS), such as internet-based multimedia services and digital TV delivery over the broadband network. Its portfolio also includes 3rd generation services like video telephony, broadband internet access, transit services for telephony and data, and services interconnecting Europe, Africa and Asia. It also provides satellite services, as well as connection to the Internet for Internet Service Providers (ISPs).
CYTA is in constant search to provide new or improved services and products to its customers, by utilizing the whole spectrum of its infrastructure. Successful introduction of supplementary services enriches its portfolio, adds value to the organization and in turn, enhances customer satisfaction and loyalty. Such services span the areas of technologies convergence, personal communication and the tele-applications sector or increase in broadband connections and communication speeds. As understood, to achieve its mission the organization must own and operate high-performance networks with high reliability and huge capacity, essentially a network made up of an interconnection of local area networks (LANs) within a limited geographical area, also known as corporate area network (CAN). The purpose of this seminar is to present the major concepts such a CAN is based on and as well its evolution and advancement with reference to interconnection issues and information technology within. Participation of the audience through discussion will be encouraged.
Short Bio:
Panayiotis Ioannides currently works at Cyprus Telecommunications Authority in Nicosia as Engineer in the Prepaid Mobile Telephony Network. He earned an MS degree in Electrical Engineering from Arizona State University in 2004. He received Diploma in Electrical and Computer Engineering from the National Technical University of Athens in 2002, and recently MBA degree from the University of Cyprus. His research interests include Smart Antennas and Wireless Communications. In 2007, Morgan & Claypool Publishers published the Synthesis Lecture “Introduction to Smart Antennas” in which Panayiotis is co-author with Professor Constantine A. Balanis of ASU.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Norman Christopher
Affiliation: Oracle Corporation, Cyprus
Category: Invited Course Lecture
Location: Room B121, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Wednesday, January 19th, 2011
Time: 13:00-14:00 EET
Host: Demetris Zeinalipour (dzeina AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2011.norman
Abstract:
This talk will cover the following topics: Oracle Overview. Database Market Position. Architectural Overview.
Installation. Tutorial/Demo (Enterprise Manager, Creating a Session, DDL & DML in SQL).
Short Bio:
Norman Christopher is principal consultant in Oracle Corporation. Experience: 19 Years, Oracle Database and ERP Applications technical and functional principal consultant. Skill Set: Applications analysis & development, Senior Oracle DBA (Versions 5,6,7,8, 9i, 10&11g), fluent on windows and all flavors of Unix. Software: Oracle Forms & Reports, C, PLSQL, Pro*C. Employment History Highlights: International Oracle Corporation - Principal Consultant: current employer (Four years), NCR Corporation - Senior IT Consultant (Five years), AT&T - IT Consultant, Local
Logicom Software Solutions - Oracle Department Manager (Four years), Globalsoft - Oracle Applications Technical Manager (Two years)
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Christophoros Panayiotou
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Thursday, Dec. 9th, 2010
Time: 10:00-11:00 EET
Host: George Samaras (cssamara AT ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.panayiotou
Abstract:
Mobile (wireless) clients present a new and more demanding breed of users. Solutions provided for the desktop users are often found inadequate to support this new breed of users. Personalization is such a solution. The wireless user differs from the desktop user in that his handheld device is truly personal. It roams with the user and allows him access to info and services at any given time from anywhere. As the wireless user is not bound to a fixed place and to a given time period, factors such as time and current experience becomes increasingly important for him. His context and preferences are now a function of time and experience and the goal of personalization is to match the local services to this time-depended preferences. In this thesis we try to exploit the importance of time and experience in personalization for the wireless user and will present a system that anticipates and compensates the time-dependant shifting of user interests.
Short Bio:
Christophoros Panayiotou is currently a PhD candidate in Computer Science at the University of Cyprus.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Seminar entitled:
Speaker: Angelos Marnerides
Affiliation: Lancaster University, UK
Category: Seminar
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Wednesday, December 15th, 2010
Time: 10:00-11:00 EET
Host: Andreas Pitsillides (andreas.pitsiilides AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.marnerides
Abstract:
Traffic characterization poses a significant challenge due to the
unstable and fluctuated behavior exhibited by network traffic
dynamics. Modeling techniques developed for volume-based
traffic profiling (i.e., based on packet and/or byte counts) rely on
the statistical assumptions of stationarity, Gaussianity and
linearity, whose applicability has not been thoroughly investigated
throughout past and recent work. We argue that these modeling
assumptions should be rigorously validated since they determine
the accuracy of any model applied to describe the traffic process.
In this work we introduce and illustrate the suitability of Time-
Frequency (TF) representations and the Hinich algorithms for the
validation of modeling assumptions on captured backbone and
edge link network traces. Through the employment of these
algorithms, we statistically show that link traffic is extremely
dynamic and model characteristics change in small timescales. In
addition, we propose the bispectrum as a good candidate for
volume-based traffic profiling since it can accurately capture
traffic dynamics. Furthermore, we highlight the benefits of a
transport-layer traffic decomposition approach where protocols
are modeled independently and protocol-specific characteristics
are revealed, as opposed to analysis based solely on volume
aggregates.
Short Bio:
Angelos Marnerides received the BSc degree in Computer Science from
Middlesex University, in London, in 2006 and the MSc degree in Critical
Software Engineering from the University of Lancaster, UK, in 2007. He is
currently a PhD candidate, funded by the UK Engineering and Physical
Sciences Research Council (EPSRC) at the University of Lancaster, UK and
is expected to earn his doctorate in computer science, in summer 2011. His
research is mainly dealing with the characterization of traffic dynamics
and anomaly detection on backbone and edge networks using statistical,
information-theoretic and signal processing techniques. During his PhD,
Angelos has been involved with 2 EU Projects (ANA, Resumenet) as well as
with the India-UK Centre of Excellence in Next Generation Networks
(IU-ATC).
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The Department of Computer Science at the University of Cyprus cordially invites you to the Seminar entitled:
Speaker: Aristodemos Cleanthous
Affiliation: University of Cyprus, Cyprus
Category: Seminar (PENEK Research Results)
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, November 30th, 2010
Time: 11:30-12:30 EET
Host: Chris Christodoulou (cchrist AT ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.cleanthous2
Abstract:
This thesis proposes a novel computational model of internal conflict which aims to provide further understanding on this highly complex and perplexing condition of the human brain. In particular, the purpose of this thesis is to identify specific factors which influence and enable internal conflict to be resolved by self-control behaviour.
Individuals are likely to experience an internal conflict when evaluating the same outcomes of choice along distinct dimensions or criteria. A value conflict of this sort can be resolved as if it was a result of strategic interaction between rational subagents of the brain. The particular setting for this interaction is a well-studied theoretical game, the Iterated Prisoners Dilemma, where the mutual cooperation outcome of the game corresponds to the behaviour of self-control. The computational system developed for the purposes of this thesis realises this particular view of internal conflict by implementing two spiking neural networks as two agents competing in the Iterated Prisoners Dilemma, where the agents pursue individual value maximisation through simultaneous but independent learning.
This high-level game theoretical approach to the problem of internal conflict incorporates at the same time biological realism through the employed neuronal model, the process of learning, as well as by relating the agents and their actions in the game with particular brain regions and their functioning. In particular, the spiking neural networks comprise of leaky integrate-and-fire neurons, while the learning process is implemented by reinforcement of stochastic synaptic transmission as well as by reward-modulated spike-timing-dependent plasticity with eligibility trace. Moreover, the action of cooperation and defection by each agent maps to a greater relative activity of fronto-parietal and limbic system areas respectively.
As demonstrated through numerous simulations, the artificial neuronal system behaved efficiently in the game theoretical framework because the learning agents implemented the optimum result for the system through consistent mutual cooperation. Therefore self-control behaviour can indeed be learned (since it corresponds to mutual cooperation), and as showed by further results, it is enhanced by strong reward-correlated memory. Moreover, the ability of the agents to adopt optimal counter strategies as a response to their competitors, enabled the identification of particular value structures that characterise internal conflicts of low and high intensity that promote or hinder the attainment of self-control behaviour.
In the process of obtaining the results which are relevant to the problem of self-control behaviour and internal conflict, this thesis work applied for the first time spiking neural agents combined with biological plausible reinforcement learning in a highly demanding multiagent task. In addition, further results with our system showed that high firing irregularity at high rates enhances learning.
Short Bio:
Aristodemos Cleanthous received his B.Sc in Mathematics and Economics at the London School of Economics and Political Science (LSE) in 2002. He further studied at the University College London (UCL), receiving his M.Sc in Computer Science in 2005. In 2006 he started his PhD degree at Department of Computer Science, University of Cyprus and on 29 October 2010 he has successfully defended his PhD thesis and the 5-member examination committee unanimously recommended to the Senate of the University of Cyprus the award of a PhD degree to him. His research interests include computational neuroscience and reinforcement learning with special application on the problem of internal conflict and self-control behaviour. His research has been funded by the Cyprus Research Promotion Foundation and the University of Cyprus.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Presentation entitled:
Speaker: Stuart Mackenzie
Affiliation: FMT Worldwide, Cyprus
Category: Presentation
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Wednesday, November 24th, 2010
Time: 12:00-13:30 EET
Host: Marios Dikaiakos (mdd AT ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.mackenzie
Abstract:
FMT is the privately held, Australian-based software development house that invented Application Mediation, which is fast gaining market backing as a global standard in IT architecture. FMT services leading organizations around the world, was named a "Cool Vendor in Secure Business Enablement" by global leading analyst firm, Gartner Inc, and its shareholders include IBM.
This presentation will show how ‘Application Mediation‘ technology analyses web data and performs real time interventions to change web application behaviour without making any application code changes.
Short Bio:
Stuart Mackenzie is responsible for the strategy, development and implementation of FMT strategic alliances and rapid business growth. Stuart previously managed multiple vendor and partner relationships to drive secure e-business enablement across developed and developing markets as part of GE Money's Global Fraud Management team. Before that, he served as Remote Channel Fraud Strategy and Policy Manager at Barclays Bank where he pioneered anti-fraud solutions in response to the emergence of phishing and delivered 3D Secure technology to Barclaycard's credit and debit card portfolios. Stuart is a former member of APACS' E-Banking Fraud Liaison Group (the UK's Association for Payment and Clearing Services) and won the 2005 Anti-Fraud Strategy of the Year honor at the UK's Finance Sector Technology Awards.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Aristodemos Cleanthous
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Friday, October 29th, 2010
Time: 9:30-10:30 EET
Host: Chris Christodoulou (cchrist AT ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.cleanthous
Abstract:
This thesis proposes a novel computational model of internal conflict which aims to provide further understanding on this highly complex and perplexing condition of the human brain. In particular, the purpose of this thesis is to identify specific factors which influence and enable internal conflict to be resolved by self-control behaviour.
Individuals are likely to experience an internal conflict when evaluating the same outcomes of choice along distinct dimensions or criteria. A value conflict of this sort can be resolved as if it was a result of strategic interaction between rational subagents of the brain. The particular setting for this interaction is a well-studied theoretical game, the Iterated Prisoner’s Dilemma, where the mutual cooperation outcome of the game corresponds to the behaviour of self-control. The computational system developed for the purposes of this thesis realises this particular view of internal conflict by implementing two spiking neural networks as two agents competing in the Iterated Prisoner’s Dilemma, where the agents pursue individual value maximisation through simultaneous but independent learning.
This high-level game theoretical approach to the problem of internal conflict incorporates at the same time biological realism through the employed neuronal model, the process of learning, as well as by relating the agents and their actions in the game with particular brain regions and their functioning. In particular, the spiking neural networks comprise of leaky integrate-and-fire neurons, while the learning process is implemented by reinforcement of stochastic synaptic transmission as well as by reward-modulated spike-timing-dependent plasticity with eligibility trace. Moreover, the action of cooperation and defection by each agent maps to a greater relative activity of fronto-parietal and limbic system areas respectively.
As demonstrated through numerous simulations, the artificial neuronal system behaved efficiently in the game theoretical framework because the learning agents implemented the optimum result for the system through consistent mutual cooperation. Therefore self-control behaviour can indeed be learned (since it corresponds to mutual cooperation), and as showed by further results, it is enhanced by strong reward-correlated memory. Moreover, the ability of the agents to adopt optimal counter strategies as a response to their competitor’s, enabled the identification of particular value structures that characterise internal conflicts of low and high intensity that promote or hinder the attainment of self-control behaviour.
In the process of obtaining the results which are relevant to the problem of self-control behaviour and internal conflict, this thesis work applied for the first time spiking neural agents combined with biological plausible reinforcement learning in a highly demanding multiagent task. In addition, further results with our system showed that high firing irregularity at high rates enhances learning.
Short Bio:
Aristodemos Cleanthous received his B.Sc in Mathematics and Economics at the London School of Economics and Political Science (LSE) in 2002. He further studied at the University College London (UCL), receiving his M.Sc in Computer Science in 2005. Since 2006 he is a PhD candidate at the Department of Computer Science, University of Cyprus. His research interests include computational neuroscience and reinforcement learning with special application on the problem of internal conflict and self-control behaviour. His research has been funded by the Cyprus Research Promotion Foundation and the University of Cyprus.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lectures entitled:
Speaker: Prof. Petr Lansky
Affiliation: Academy of Sciences, Czech Republic
Category: Invited Course Lectures
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Lecture 1 Date/Time: Tuesday, October 19th, 2010, 15:00-18:00 EET
Lecture 2 Date/Time: Wednesday, October 20th, 2010, 15:00-18:00 EET
Host: Chris Christodoulou (cchrist AT ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.lansky
Abstract:
A mathematical model is always an attempt for approximation of some real, usually dynamical, system using one or more equations which represent behavior of the system. To which extent the properties of reality are neglected determines compatibility between the model and the real object, but also tractability of the model. The obvious value of the models is based on their analytical power permitting to test the scientific hypotheses. Variable assumptions about the system are reflected by different versions of the model and can be exploited when verifying and interpreting the experimental results. Less obvious, but not less important, role of the models is based on their indirect contribution to organizing and integration of existing knowledge about the nature. By constructing the models we realize the missing parts of our knowledge and the new experimental questions are proposed. These facts, so well known in physics and engineering, have been recently taken into account in biology as well. These general notes hold in neuroscience even more obviously due to the long tradition of mathematization of this branch of science. The seminal paper (Lapicque, 1907) was published more than hundred years ago. And the most significant stimulus for formalization of the neuroscience research was the neuronal model of Hodgkin and Huxley published in 1952, almost sixty years ago. Nevertheless, more recently in the center of interest appeared a random component contained in the neuronal activity. There has been a long-lasting discussion about the role of this randomness and the course is devoted to this topic.
Note: The lectures that will be given (Lecture 1 and Lecture 2) will only summarize the results and formal details will be omitted. It should permit to follow the talks without preliminary background.
Lecture 1: In the first lecture, the neural models characterized as stochastic will be presented starting from the simple ones to their more complex versions. All of them can be characterized by the term "stochastic process", either one- or multidimensional, such that its dynamics describe neuronal behavior in time and in dependency on its inputs. Such stochastic processes are usually continuous in time, but their values change either continuously or with discrete jumps. The basic problem is how close one to the other are these two variants, thus we discuss the problem of diffusion approximation. The next connecting feature is the "first-passage-time problem". It is a question about the properties of the time interval during which a deterministic threshold is reached by a stochastic process. Thus, instead of a trajectory of a random process we have at disposal this random variable only. Importance of this task follows from the fact that the basic principle of neuronal transmission is transformation of an analog signal, for example of the membrane potential, into a sequence of discrete neuronal pulses, so called action potentials, which appear randomly in time and this phenomenon is modeled as the first- passage time. Then, the basic question is to deduce statistical properties of the first- passage time from the properties of the input signal.
Lecture 2:
The second lecture will be devoted to the statistical inference for spiking neural data and in the context of stochastic neural modeling. The crucial question of all verification procedures for model construction is the identification and estimation of the parameters. Despite that any stochastic model is just an approximation of reality, it is important to underline its probabilistic form and thus the fact that it covers all possible situations and we have to judge the probability distribution of these situations. To determine the parameters as precisely as possible is an unavoidable condition for that purpose, and in addition we need to quantify the precision. Most of the models discussed in the first lecture are not only descriptive, but their parameters have some biological interpretation, despite the models are very simple and far from biophysical realism. Therefore for quantitative comparison of models and data it is important to obtain the values of the parameters. The model construction permits to use statistical methods for testing the significance of the parameters as well as their mutual differences.
Short Bio:
Petr Lansky is a head of the Department of Computational Neuroscience at Academy of Sciences of the Czech Republic. He gained his doctorate in probability theory and mathematical statistics at Charles University, Prague studying stochastic diffusion neural models. While continuing his research he published more than 100 papers in the field of computational neuroscience and got visiting positions at several universities and research institutions all around the world, including Institut National de la Recherche Agronomique, France; North Carolina State University, Raleigh; University of California, Berkeley; Osaka University, Japan; Centre de Physique Theorique de l’Universite Marseille, France; Università di Torino, Italy and others. Among the topics of his research belongs studies principles of olfactory neural processing in insects using a combination of theoretical approach and mathematical and computer modeling, Models of sensory neurons, Statistical inference for spike train data, Enhancement of signal by noise in simple neuronal models, Information methods in spike train analysis.
For additional information please download the following: Lectures Overview in PDF |
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Despina Michael
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Thursday, July 15th, 2010
Time: 9:00-10:00 EET
Host: Yiorgos Chrysanthou (yiorgos AT ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.michael
Abstract:
Real-time realistic rendering of a computer generated scene is one of the core research areas in computer graphics as it is required in several applications such as computer games, training simulators, medical and architectural packages and many other fields.
The key factor of realism in the rendered images is the simulation of light transport based on the given lighting conditions. More natural results are achieved by using luminance values near to the physical ones. However, the vast range of real luminance values has a far greater range of values than what can be displayed on standard monitors. As a final step to the rendering process a Tonemapping operator needs to be applied in order to transform the values in the rendered image to displayable values.
A full rendering pipeline that integrates illumination and tonemapping, giving high quality results in real-time frame rate is useful to exist. Such a rendering pipeline would be used in interactive applications which require a high degree of realism.
Illumination of a scene is usually approximated with the rendering equation. Current illumination algorithms, in order to achieve high frame rates, compromises the quality with assumptions for several factors that rendering equation depends on, or assuming static scenes so they can exploit precomputations. Such precomputations usually have huge amount of memory requirements.
The computational cost increases more, with the increase in the number of light sources and the number of vertices of the objects in the scene. In this thesis we propose an illumination algorithm for dynamic scenes which its run-time performance is not affected by these parameters and has only moderate memory requirements. In this way we can have high frame rates without compromising the quality. The key idea of our algorithm is the pre-integration of contribution of all light sources in a single 3D vector, in such a way that this value is valid for any possible receiver. At run-time this value is used to compute the radiance at each point of the scene based on its known orientation.
Recent illumination algorithms, including ours, use environment maps to represent the incident lighting in the scene. Environment maps enable natural environment lighting conditions to be used, thus increasing the realism of the obtained result. Environment maps usually have high dynamic range (HDR) values allowing representation of luminances closer to the natural ones as compared to standard low dynamic range (LDR) images. When HDR environment maps are used, the whole rendering process is done in HDR space, giving an HDR image as output. Typically this needs to be tonemapped into LDR values that can be displayed on standard monitors.
There are two categories of tonemapping algorithms: local tonemapping operators produce high quality LDR images in low frame rates, while global tonemapping operators produce moderate quality results in high frame rates. Neither of these categories is suitable in our case where we need to use tonemapping for real-time realistic results. In this thesis, we propose a new framework: selective tonemapping which addresses both requirements. The key idea of this framework is to apply the expensive computations of Tonemapping only to the areas of images which are perceptually important. Selective tonemapping combines the advantages of both categories of current tonemapping algorithms.
A full rendering system has been developed which integrates HDR illumination computation and the selective tonemapping framework. Results show high quality images at real-time frame rates. Moreover, it is demonstrated that the application of tonemapping makes illumination algorithms more tolerant to visual perceptual errors.
Short Bio:
Despina Michael is a PhD Candidate at the Department of Computer Science, University of Cyprus.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Presentation entitled:
Speaker: Dimitris Gkanatsios
Affiliation: Microsoft, Greece
Category: Presentation
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, June 29th, 2010
Time: 15:00-16:00 EET
Host: Yiorgos Chrysanthou (yiorgos AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.microsoft
Abstract:
We will discuss about Microsoft's vision 'Three screens and the cloud' and its relevant technologies (including but not limited to Azure, WPF, Silverlight, XNA, Windows Phone), and other innovative Microsoft products and technologies.
Short Bio:
Dimitris - Ilias Gkanatsios has been working as an Academic Developer Evangelist in Microsoft Greece since 2008. Before Microsoft, he worked as a software developer for 4 years. He has graduated from Department of Informatics and Telecommunications of the University of Athens, and is currently completing his Master studies at the University of Piraeus.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Yiannos Mylonas
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Friday, June 4th, 2010
Time: 12:00-13:00 EET
Host: Andreas Pitsillides (andreas.pitsiilides AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.mylonas
Abstract:
A significant issue in vehicular ad hoc networks (VANETs) is the design of an effective broadcast scheme which can facilitate the fast and reliable dissemination of emergency warning messages (EWM) in the vicinity of an unexpected event, such as a car accident. In this work we propose a novel solution to this problem, which we refer to as Speed Adaptive Probabilistic Flooding. The scheme employs probabilistic flooding to mitigate the effects of the broadcast storm problem, typical when using blind flooding, and its unique feature is that the rebroadcast probability is regulated adaptively based on the vehicle speed to account for varying traffic densities within the transportation network. The motivation behind this choice is the identification of the existence of phase transition phenomena in probabilistic flooding in VANETs which dictates a critical probability is affected by the varying vehicle traffic density, and shown to be linearly related to the vehicle speed (a locally measurable quantity). The protocol enjoys a number of benefits relative to other approaches: it is simple to implement, it does not introduce additional communication burden, as it relies on local information only, and it does not rely on the existence of a positioning system (e.g. GPS) with its associated high signaling overhead for the exchange of beacon messages for mutual awareness. The scheme is evaluated on different sections of the highway system in the City of Los Angeles and Cyprus, using an integrated platform combining the OPNET Modeler and the VISSIM simulator. Simulation results indicate that the proposed scheme fulfills its design objectives, as it achieves high reachability and low latency of message delivery in a number of scenarios. The scheme is shown to be independent of the number of lanes of the freeway where it is applied, and it continuous to perform as required when uni-directional traffic is replaced by bi-directional traffic. Moreover, the SAPF algorithm has been shown to outperform blind flooding in all scenarios and especially in cases of heavy congestion. Its robustness with respect to different number of hops, different speed limits on the freeway where it is applied, and different transmission range of the vehicles participating in the VANET has also been demonstrated. Finally, the performance of the SAPF algorithm is shown to be comparable to schemes which offer increased opportunities to exhibit superior performance by assuming the presence of GPS systems on board the vehicles.
Short Bio:
Yiannos received his B.Sc in Computer Engineering from Oregon State University in 1998. In 2001, he received his M.Sc in Computer Science from University of Cyprus. He is currently pursuing his PhD degree at the University of Cyprus under the supervision of Prof. Andreas Pitsillides. From 1998 until 1999 he worked for Intel Corporation as a product support engineer. Since 2001, he is working as a Special Teaching Staff in the department of Computer Science at the University of Cyprus. His research interests include, Computer Networks, Vehicular Ad-Hoc Networks and Intelligent Transportation Systems (ITS).
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The Department of Computer Science at the University of Cyprus cordially invites you to the Seminar entitled:
Abstract:
Monitoring network traffic and classifying applications are essential functions for network administrators. These tasks are becoming increasingly challenging since (a) many applications obfuscate their traffic, e.g., using nonstandard ports, and (b) new applications constantly appear. This suggests the need for a behavioral-based approach, where the detector looks for fundamental behaviors of the application that are both intrinsic to the application and distinct from the rest of the traffic. Identifying intrinsic behaviors makes it difficult for application writers to disguise such behaviors without defeating the very purpose of the application. For example, it will be challenging to design a P2P file-sharing protocol and at the same time eliminate the need for a peer to interact with multiple other users in the network. In our work, we propose a graph-based representation of network traffic, which captures the network-wide interactions of applications. In these graphs, nodes are individual IP address and edges between nodes represent particular communications. For example, an edge might represent the exchange of a single packet, or the exchange of at least ten packets of any type. We call such graphs "Traffic Dispersion Graphs" or TDGs. Our study shows that TDGs provide valuable information about the network and the applications being used. As a proof of concept, we build a graph-based traffic classification system and show it outperforms the state-of-the-art in detecting traffic on backbone links. Our results are very promising, showing that TDGs can provide the basis for the next generation of network monitoring tools.
Short Bio:
Marios Iliofotou received the B.S. degree in electrical and computer engineering from the Technical University of Crete, in Greece, in 2005 and the M.S. degree in computer science from the University of California, Riverside, in 2007. He is currently a PhD candidate at the University of California, Riverside and is expected to earn his doctorate in computer science, in summer 2010. His current research investigates the effectiveness of graph-based algorithms for network monitoring and security. During his PhD, Marios has worked as an Intern at the Lawrence Livermore National Laboratory, Telefonica Research (Internet research group), and Cisco Systems, Inc.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Demosthenis Georgiadis
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Wednesday, May 26th, 2010
Time: 9:00-10:00 EET
Host: George Samaras (cssamara AT ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.georgiadis
Abstract:
Computer Supported Collaborated Work-related (CSCW) applications is becoming a trend for most business and organizations. A big challenge is to deploy an efficient CSCW system where the communication media is wireless, users are mobile and uses mobile devices with limited capabilities. A sector that utilizes such CSCW systems is the healthcare domain. Due to the sensitive area of healthcare provision, additional features are needed in a CSCW system like virtual teams, appropriate computational model for the eHealth domain, dynamic creation of collaboration workflows, proactive diaries and automatic triggered events upon time expiration. This thesis presents such a CSCW system that support these features not only within an organization but across organizations as well. It also provides evaluation and feedback from its application in a real world environment, thus demonstrating its applicability and effectiveness.
Short Bio:
Dimosthenis Georgiadis is currently a PhD candidate in the Computer Science of the University of Cyprus. Due to the last years he worked in numerous projects evolved in the eHealth domain. Such projects are DITIS, Linkcare, HS24, mPower and MELCO. During these projects he advanced in user requirements collection, building intelligent web interfaces, carried out surveys, collect and analyze data and conduct interviews and trainings with healthcare professionals. His PhD thesis is focused in wireless collaboration in the eHealth domain.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Christodoulos Nicolaou
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, May 25th, 2010
Time: 14:30-15:30 EET
Host: Constantinos Pattichis (pattichi AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.nicolaou
Abstract:
Optimal Graph Design is a problem frequently occurring in several common applications ranging from designing communication and transportation networks to discovering new drugs. More often than not the graphs to be designed need to satisfy multiple, conflicting, objectives e.g. total length, complexity or other shape and property limitations. Our research proposes MEGA, an algorithmic framework for the solution of the problem of multiobjective optimal graph design for labeled, undirected graphs. The method uses multi-objective evolutionary graphs, a graph-specific meta-heuristic optimization technique that combines evolutionary algorithms with graph theory and local search techniques exploiting domain-specific knowledge, to efficiently explore the feasible search space and obtain multiple equivalent compromising solutions. The proposed algorithm introduces a novel niching mechanism that takes into account both parameter and objective space solution diversity. Moreover, the method implements a self-adaptive approach to control and ensure appropriate local search use. In the experimental section we present results obtained for the problem of designing molecules satisfying multiple pharmaceutically relevant objectives. The results suggest that the method can provide a variety of valid, interesting graph solutions. In comparisons with commonly used algorithms, MEGA is found to produce better results at a statistically significant level.
Short Bio:
Christodoulos Nicolaou is a PhD candidate at the Computer Science department of the University of Cyprus. He has a MSc and a BSc in Computer Science from Florida State University, USA and a Teacher's degree from the Pedagogical Academy of Cyprus. He has over 10 years of hands-on industrial experience in knowledge discovery and management, data mining and optimization methods. Christos has been involved in the design and implementation of several commercial software applications in the area of drug discovery with emphasis on chemoinformatics. He is currently a Scientific Coordinator at the Computational-base Science and Technology Research Center of the Cyprus Institute in Nicosia, Cyprus.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Minas Karaolis
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Tuesday, May 25th, 2010
Time: 09:00-10:00 EET
Host: Constantinos Pattichis (pattichi AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.karaolis
Abstract:
Εκτιμήσεις του παγκόσμιου οργανισμού υγείας δείχνουν ότι οι καρδιακές παθήσεις είναι και θα παραμείνουν στις επόμενες δεκαετίες η κύρια αιτία θανάτου παγκόσμια. Οι παράγοντες κινδύνου πάθησης ενός καρδιακού επεισοδίου είναι γνωστοί, αλλά όχι τόσο ο συνδυασμός αυτών, και πως μπορεί η καλύτερη διαχείριση των πολλαπλών παραγόντων κινδύνου να βοηθήσει στην μείωση των περιστατικών.
Στόχος της διατριβής αυτής είναι η ανάπτυξη ενός καινοτόμου ολοκληρωμένου συστήματος που θα υποστηρίζει την αξιολόγηση των παραγόντων κινδύνου σε καρδιαγγειακές βάσεις δεδομένων και την εξόρυξη κανόνων εκτίμησης κινδύνου βασισμένων σε αλγόριθμους δένδρων αποφάσεων και κανόνων συσχέτισης.
Η πρωτοτυπία της διατριβής εστιάζεται στα ακόλουθα: i. Ανάπτυξη αλγορίθμων εξαγωγής κανόνων από δέντρα απόφασης βασισμένων σε διαφορετικά κριτήρια διαχωρισμού. ii. Ανάπτυξη ενός νέου αλγορίθμου εξαγωγής κανόνων συσχέτισης, που ονομάζεται AKAMAS, που με μια σάρωση της βάσης δεδομένων δημιουργεί κανόνες, και οι οποίοι υπολογίζονται με διαφορετικά μέτρα. iii. Ανάπτυξη μίας καινοτόμας μεθοδολογίας αξιολόγησης των στατιστικά σημαντικών κανόνων παραγόντων κινδύνου για εκτίμηση κινδύνου για ανεύρεση των καλύτερων κανόνων βασισμένη σε πολλαπλά μέτρα.
Το προτεινόμενο σύστημα έχει εφαρμοστεί για την εξόρυξη κανόνων παραγόντων κινδύνου σε βάσεις δεδομένων για καρδιακά επεισόδια με έμφραγμα μυοκαρδίου, αγγειοπλαστικής και αρτηριακής παράκαμψης με πολύ ικανοποιητικά αποτελέσματα.
Short Bio:
Απόκτησε το Diplom του (ισότιμο Masters') στην επιστήμη της πληροφορικής από το Πολυτεχνείο Carolo Wilhelmina Braunschweig, Μπραουνσβάϊγκ, Γερμανία. Δούλεψε τέσσερα χρόνια σαν επιστημονικός συνεργάτης στο Πολυτεχνείο Carolo Wilhelmina Braunschweig. Ανάπτυξε μια αυτόματη δημιουργία σχεδίων βρόχων για βιομηχανικές εγκαταστάσεις στην εταιρία Preussag στη Γερμανία, χρησιμοποιώντας software engineering και βάσεις δεδομένων. Ανάπτυξε ένα σύστημα για τη διαχείριση των χημικών και τοξικών αποβλήτων του Πολυτεχνείου Carolo Wilhelmina Braunschweig. Δούλεψε για πέντε χρόνια σαν καθηγητής πληροφορικής στα επιμορφωτικά προγράμματα του υπουργείου παιδείας. Έχει δουλέψει στο τμήμα τεχνικής υποστήριξης και στο τμήμα εκπαίδευσης της εταιρίας Prisma Computers Ltd (Apple) και της εταιρίας Ακτίνα (Microsoft authorised). Δούλεψε στο Τμήμα Πληροφορικής, Τράπεζα Κύπρου, Αναλυτής - Προγραμματιστής. Επιστημονικός συνεργάτης στο Πανεπιστήμιο Κύπρου. Από το 2005 Καθηγητής στη Μέση Εκπαίδευση.
Μέλος της επιτροπής για την δημιουργία νέων αναλυτικών προγραμμάτων στην Μέση Εκπαίδευση. Τα τωρινά επιστημονικά του ενδιαφέροντα περικλείουν εφαρμογές με εξόρυξη δεδομένων και ανάπτυξη αλγορίθμων για συστήματα ιατρικής διάγνωσης. Στο θέμα αυτό έχει δέκα δημοσιεύσεις. Μέλος του ΙΕΕΕ, ACM, CCS, ETEK και ΣΥ.ΚΑ.Π.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Dr. Chryssis Georgiou
Affiliation: University of Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Tuesday, March 23th, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.georgiou
Abstract:
Data survivability is undoubtedly essential in today's systems and applications. The only way
to ensure survivability of data is through redundancy: the data is replicated and maintained at
several network locations. Replication introduces the challenge of maintaining consistency
among the replicas despite system asynchrony and failures. Doing so efficiently, makes this
task even more challenging.
We investigate this challenging problem by studying efficient implementations of atomic read/write
sharable objects in asynchronous message-passing systems. An atomic read/write object allows
concurrent processes to share information through a common variable, as if they were accessing
this variable in a sequential manner. This abstraction, usually referred as atomic register, is
fundamental in distributed computing and is at the heart of a large number of distributed algorithms.
The object is replicated to several failure-prone server processes and failure-prone reader and writer
client processes perform read and write operations by communicating with the servers. We are
particularly interested in wait-free implementations of atomic registers, where any read or write
operation by any non-faulty client eventually completes, despite of the operational status of the
other clients. The efficiency of such implementations is expressed with the read/write operation
latency which is measured by the number of communication rounds required between clients
and servers for each operation to complete.
In this talk, I will present the conditions under which wait-free implementations of SWMR and
MWMR atomic registers in asynchronous message-passing systems can be both efficient and
fault-tolerant. I will also demonstrate how such implementations (when possible) can be constructed.
Short Bio:
Chryssis Georgiou is an Assistant Professor in the Department of Computer Science at the
University of Cyprus. He holds a Ph.D. (December 2003) and M.Sc. (May 2002) in Computer
Science and Engineering from the University of Connecticut and a B.Sc. (June 1998) in
Mathematics from the University of Cyprus. He has worked as a Teaching and Research Assistant
at the University of Connecticut, USA (1998-2003) and as a Visiting Lecturer (2004) and a
Lecturer (2005-2008) at the University of Cyprus. His research interests span the Theory and Practice
of Fault-tolerant Distributed and Parallel Computing. He has published in top journals and conference
proceedings in his area of study and he has co-authored a book on Distributed Cooperative Computing.
He served on Program Committees of top conferences in Distributed Computing and he is on the
Steering Committee (2008-2010) of the International Symposium on Distributed Computing (DISC).
Personal website: http://www.cs.ucy.ac.cy/~chryssis
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Marios Kleanthous
Affiliation: University of Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Tuesday, March 16th, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.kleanthous
Abstract:
The importance of caches and memory hierarchy has increased over time due to
the growing gap between processor and memory performance. Caches,
consequently, have been central to numerous research studies. Several
techniques have been proposed to improve various aspects of caches by
reducing their miss rates, size, latency and energy. Most of these
techniques attempt to exploit different types of properties of memory
addresses and data, such as locality, predictability, and redundancy.
Previous work identified a new cache property that may influence cache
performance: the Cache-Content-Duplication (CCD). This phenomenon occurs
when there is a miss for a block in a cache and the content of the missed
block resides already in the cache in another block with a different
address.
This presentation will give an insight on the effects of CCD on instruction
caches and the hardware mechanism that detects and exploits CCD. Also, we
will examine the importance of CCD in shared caches which are now widely
used by modern Chip Multi-Processors (CMP) and Simultaneous Multi-Threading
(SMT) technology.
Short Bio:
Marios Kleanthous completed his undergraduate degree in the Department of
Informatics and Telecommunications at the National and Kapodistrian
University of Athens in 2004. The same year he started his M.Sc degree in
Computer Science at the University of Cyprus. In 2006 he completed his M.Sc
degree and became a Ph.D student under the supervission of Prof. Yiannakis
Sazeides. Currently, he is a Ph.D student in Computer Science Department at the
University of Cyprus and also a member of the Xi-Computer Architecture
Research Group where he works on the Cache Content Duplication Phenomenon.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Norman Christopher
Affiliation: Oracle Corporation
Category: Invited Course Lecture
Location: Room B121, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Friday, March 19th, 2010
Time: 12:00-13:30 EET
Host: George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.norman
Abstract:
This talk will cover the following topics: Oracle Overview. Database Market Position. Architectural Overview.
Installation. Tutorial/Demo (Enterprise Manager, Creating a Session, DDL & DML in SQL).
Short Bio:
Norman Christopher is principal consultant in Oracle Corporation. Experience: 19 Years, Oracle Database and ERP Applications technical and functional principal consultant. Skill Set: Applications analysis & development, Senior Oracle DBA (Versions 5,6,7,8, 9i, 10&11g), fluent on windows and all flavors of Unix. Software: Oracle Forms & Reports, C, PLSQL, Pro*C. Employment History Highlights: International Oracle Corporation - Principal Consultant: current employer (Four years), NCR Corporation - Senior IT Consultant (Five years), AT&T - IT Consultant, Local
Logicom Software Solutions - Oracle Department Manager (Four years), Globalsoft - Oracle Applications Technical Manager (Two years)
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Michelle Mazzucco
Affiliation: University of Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Friday, March 12th, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.michele
Abstract:
As IT systems are becoming more and more important, one of the main concerns is that users may face major breakdowns and eventually incur major costs if computing systems do not meet the expected performance requirements: customers expect reliability and performance guarantees, while under-performing systems lose revenues. For example, it has been reported that Amazon tried delaying the page generation by 100 ms and found out that even very small delays would result in substantial and costly drops in revenue (1% sales drop for 100 ms delay).
In this talk I will discuss some performance models aiming at optimizing the revenue earned by IT providers running jobs subject to Quality of Service (QoS) constraints and present a middleware architecture for Web Service provision.
Experimental results show that revenues can be dramatically improved by imposing suitable conditions for accepting incoming traffic.
Short Bio:
Michele Mazzucco earned his BSc and MSc at the University of Bologna (Italy) in 2003 and 2005, and received his PhD from Newcastle University (UK) in 2009 (advisor Prof. Isi Mitrani) with a thesis on optimization problems in the context of commercial data centers.
From 2006 to 2008 he worked as a Research Associate at N'cle, funded by British Telecom (BT). He is currently a Marie Curie Fellow at the University of Cyprus.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Vasos Vassiliou
Affiliation: University of Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Tuesday, March 9th, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.vasos
Abstract:
The task of a communication network is to provide traffic transportation services between end users by conveying data from one node to another in a reliable and timely fashion. This task means that a network is a shared entity; its services should not be dedicated to only a pair of communicating entities but to as many entities possible during its operational lifetime. Network planners have always strived to design networks that achieve high user capacities and high quality of service, but have always faced the same limitation: the finite amount of resources which a network has available for utilization in order to fulfill its task.
In this talk we will discuss the important issues that arise when trying to support video streams and other real-time multimedia applications over wireless networks. First we will illustrate the importance of applications' adaptability and QoS awareness in mobile wireless networks using as an example 3G cellular wireless networks. Then we will characterize the requirements of real-time multimedia applications and define the limitations of mobile wireless networks. Lastly, we will describe a new method for video stream adaptation based on Fuzzy Logic control, developed in the context of a UCY-funded research program.
Short Bio:
Dr. Vasos Vassiliou is a Lecturer at the Computer Science Department of the University of Cyprus since 2005. He is also the Associate Director of the Networks Research Laboratory (NetRL) at UCY. He held positions as a Visiting Lecturer at the same department (2004-2005) and as an Assistant Professor at the Computer Science Department of Intercollege (2002-2004). He has published several articles in International Conferences and Journals and participates actively in COST actions, local, and European Projects. His research interests include High Speed Network Architectures (MPLS), Mobile Networks (Mobile IP, MMPLS, Ad Hoc and Sensor Networks), Wireless Communications (Protocol enhancements for 3G/4G cellular wireless networks) and Quality of Service (QoS) and Traffic Engineering for computer and telecommunication networks. He holds an M.Sc. (1999) and a Ph.D. (2002) from the Georgia Institute of Technology both in Electrical and Computer Engineering. He is a member of IET (former IEE), IEEE, ACM, and participates in the Technical Program Committees of several international conferences, such as Globecom, VTC, PIMRC, WNET, EW. He is also an Associate Editor of the Journal of Telecommunication Systems.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Harald Gjermundrod
Affiliation: University of Nicosia, Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Friday, March 5th, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.harald
Abstract:
The North American power grids involve almost 3500 utility organizations. Existing SCADA-based status communication systems, which primarily use point-to-point links between substations and individual utility's control centers, provide inadequate cross-utility situational awareness for grid operators. The GridStat project is creating status dissemination middleware to allow creation of flexible, QoS-managed information infrastructures that address this problem for the power grid and other large, distributed infrastructures. The GridStat architecture naturally extends to nationwide, cross-infrastructure monitoring.
This talk will give an overview of the architecture and design of the GridStat framework. Three of its base line mechanisms will also be presented. The condensation function mechanism allows the users to subscribe to patterns of events and have the evaluation of these patterns be performed at the middleware layer. The mode change mechanism allows for rapid uninterrupted change of subscription sets within various regions of the infrastructure. The final mechanism to be presented is the Ratatoskr RPC that provides timeliness, redundancy, and safety properties over a Pub-Sub infrastructure.
Short Bio:
Harald Gjermundrod is currently an Assistant Professor of Computer Science at the University of Nicosia which he joined in September 2008 and an adjunct faculty at Washington State University. Prior to this he was an postdoctorate associate (2006-2008) at the High-Performance Computing Systems Laboratory in the Computer Science Department of the University of Cyprus.
His research interests include middleware, distributed computing systems, and Grid computing. Gjermundrod received his PhD, MS, and BS degrees in computer science from Washington State University in 2006, 2001, 1999 respectively and Dipl.-Ing degree from Oslo University College in 1998 (including a year as an Erasmus student at the Robert Gordon University). Gjermundrod has worked on projects funded by the EU, the National Institute of Technology(US), and the National Science Foundation(US).
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Pedro Trancoso
Affiliation: University of Cyprus, Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Tuesday, March 2nd, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.trancoso
Abstract:
Decision Support System (DSS) workloads are known to be
one of the most time-consuming database workloads that
processes large data sets. Traditionally, DSS queries have
been accelerated using large-scale multiprocessor.
The topic addressed in this work is to analyze the benefits
of using high-performance/low-cost processors such as the
GPUs and the Cell/BE to accelerate DSS query execution.
In order to overcome the programming effort of developing
code for different architectures, in this work we explore the
use of a platform, Rapidmind, which offers the possibility of
executing the same program on both Cell/BE and GPUs.
To achieve this goal we propose data-parallel versions of the
original database scan and join algorithms.
In our experimental results we compare the execution of
three queries from the standard DSS benchmark TPC-H on
two systems with two different GPU models, a system with
the Cell/BE processor, and a system with dual quad-core
Xeon processors. The results show that parallelism can be
well exploited by the GPUs. The speedup values observed
were up to 21x compared to a single processor system.
Short Bio:
Pedro Trancoso received the undergraduate degree in electrical and
computer engineering from Instituto Superior Tecnico (IST), Technical
University of Lisbon, Lisbon, Portugal, in 1993, the MSc and PhD degrees
in computer science from the University of Illinois at Urbana-Champaign,
Illinois, U.S.A., in 1995 and 1998. He is currently an Assistant
Professor at the Department of Computer Science of the University of
Cyprus, Nicosia, Cyprus. He has worked at IBM T.J. Watson Research
Center, U.S.A. as a researcher (1997), at the University of Illinois at
Urbana-Champaign, U.S.A. as a visiting scholar (2000), and at
Intercollege Limassol, Cyprus as an assistant professor (1998-2001). He
has published several papers in the area of computer architecture, with
a focus on the memory hierarchy, intelligent memory technologies,
architecture-aware optimizations for database workloads and
benchmarking, power-performance efficient architectures, multi-core
architectures, and the use of graphics processors for general purpose
applications. He was a recipient of a Fulbright scholarship to pursue
his PhD studies, an EU-Mobility grant and a HPC-Europa grant to visit,
as a researcher, the Supercomputing Center CESCA-CEPBA at the
Universitat Politecnica de Catalunya, Barcelona, Spain, in 2002 and
2005. He is a member of the CoreGrid Network of Excellence, the IEEE and
ACM. He has been a member in the Program Committee of several
International Conferences including Parallel Architecture and
Compilation Techniques, PACT 2004, and Local-Chair of Topic 7 (Parallel
Computer Architecture and ILP) of EuroPar 2005. He is currently a member
of the Editorial Board for the International Journal of High-Performance
System Architecture. He is the head of the CASPER (Computer Architecture
and Systems Performance Evaluation Research) research group. His
research interest is in the area of computer architecture, with a focus
on the memory hierarchy, intelligent memory technologies,
architecture-aware optimizations for database workloads and
benchmarking, power-performance efficient architectures, multi-core
architectures, and the use of graphics processors for general purpose
applications.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Abstract:
Theoretical applied studies of techniques for building useful intelligent
systems, something that has always been a goal of scientists and engineers.
Although Artificial Intelligence has been providing a shed to this for many
years, Computational Intelligence was restated in an effort to provide some
new links to human intelligence, and, therefore, some additional premises
and inspirations for building even smartest systems in more practical ways.
The backbone of Computational Intelligence is composed of relatively more
traditional areas such as artificial neural networks, fuzzy systems,
evolutionary computation, and genetic algorithms. The research work in this
area is outlines in four major groups: 1. Modeling Cognitive Systems; the
main purpose of this research activity is to use computational intelligence
techniques to develop systems that model several behaviors of the Brain
activity. In general, computational modeling can help to understand the
functional organization of a particular cognitive phenomenon, 2.
Computational modeling of visual selective attention; a computational model
of human visual selective attention has been implemented according to the
perspective of a systems engineer and computer scientist. The computational
model is biologically plausible and supports recent theories from the fields
of neuroscience and cognitive psychology. 3. Artificial Neural Network
Modeling; in Single Neuron Modeling, a generic neuronal model using a block
form of operational diagrams is investigated. The power of this
representation is determined by the fact that an easy identification and
extraction of the most essential features of single neuron models is
allowed. 4. Intelligent Applications; on the application side, computational
intelligent methods are investigated in many areas including, diagnostic and
prognostic systems in medicine, meteorological systems, engineering systems
design, electric load forecasting, and financial applications., and
intelligent applications.
Short Bio:
Christos N. Schizas
Professor of Computer Science, University of Cyprus. Received a B.Sc. degree
in electronic engineering from the University of London, UK, in 1978, M.B.A
degree from the University of Indianapolis, Indiana, in 1988, and Ph.D.
degree in systems theory from the University of London in 1981. He received
the 1979 William Lincoln Shelley award from the University of London for
excellence in research, and a Fulbright fellowship for collaborative
research in the USA in 1993. He was a Postdoctoral Fellow at the University
of London (1980-1983), and was Professor of Computer Information Systems at
the University of Indianapolis (1989-1991). Since 1991 he has been with the
Department of Computer Science, University of Cyprus. He served as Vice
Rector of the University of Cyprus (2002-2006). His research interests
include computational intelligence, medical informatics, diagnostic and
prognostic systems, system modelling and identification of brain activity.
He edited conference proceedings and served as associate editor of the
journal Technology and Health Care, area editor of the journal, IEEE
Transactions on Information Technology in Biomedicine, and member of the
editorial board of the journal, Intelligent Systems. He has published over
120 refereed journal and conference papers in these areas and supervised
researchers, PhD and MSc students. He is the founder of the Computational
Intelligence laboratory of the University of Cyprus. He has taken part in
European Commission initiatives for promoting the Information Society,
especially the Euro-Mediterranean partnership.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Panayiotis Zaharias
Affiliation: University of Cyprus, Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Tuesday, February 23th, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.zaharias
Abstract:
Usability is a core term in human-computer interaction (HCI).
The growing importance of usability evaluation of contemporary interactive information systems have
become evident in both researech and practice during the recent years.
The purpose of this lecture is to review current practice in how usability is measured and
to analyse problems with the measures of usability employed. Additionally this talk will present
the challenges to conducting usability studies and to research into how to measure usability.
Short Bio:
Panagiotis holds a Ph.D. degree in Information Systems (specialization on Human Computer Interaction, thesis title: A Usability Evaluation Method of E-learning Courses) from the Department of Management Science & Technology of Athens University of Economics and Business (2004). He received a first degree in Informatics from the Department of Informatics in Athens University of Economics and Business (1998), and a Masters degree in Information Systems from the MSc. Program in Information Systems in Athens University of Economics and Business (2000). His main research interests are focused on user experience, usability evaluation methods and e-Learning design. He has participated in various European and National-based research projects. He has published more than 30 papers in scientific journals and conference proceedings. He is a member of ACM Special Interest Group on Human-Computer Interaction (SIGCHI) and AACE (Association for the Advancement of Computing in Education) organization. He is currently a Visiting Lecturer at the Department of Computer Science at the University of Cyprus. He is also a research associate of IST lab/OIS Research Group of the Athens University of Economics and Business.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Georgios Fakas
Affiliation: Manchester Metropolitan University, UK and University of Cyprus, Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of
Pure and Applied Sciences, New Campus (map)
Date: Friday, February 19th, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.fakas
Abstract:
A novel Keyword Search paradigm in relational databases is proposed,where the result of a search is an Object Summary (OS). An OS
summarizes all data held about a particular Data Subject (DS) in a
database. More precisely, it is a tree with a tuple containing the
keyword(s) as a root and neighboring tuples as children. In contrast
to traditional Relational Keyword Search, an OS comprises a more
complete and therefore semantically meaningful set of information
about the enquired DS. The proposed paradigm introduces the concept of Affinity and
Importance in order to automatically generate OSs. More precisely, it
investigates and quantifies the Affinity of relations (i.e. Affinity)
and their attributes (i.e. Attributes Affinity) in order to decide
which tuples and attributes to include in the OS. A global Importance
score for each tuple of the database (denoted as Im(ti)) is
investigated and quantified. For this purpose, ValueRank, an extension
of ObjectRank, is introduced which incorporates also tuples' values in
authority flow and therefore facilitating the estimation of Importance
for arbitrary databases, e.g. trading databases etc.
Experimental evaluation on DBLP, TPC-H and Northwind databases
verifies the effectiveness and efficiency of our approach.
Short Bio:
Georgios Fakas is a Senior Lecturer at the Department of Computing and
Mathematics of the Manchester Metropolitan University, UK. Currently,
he is at the University of Cyprus under the "Hosting of Experienced
Researchers from Abroad" Programme of the Cyprus Research Promotion
Foundation (RPF). He also worked as a Research Associate at the
Institute for Automatic Control of the Swiss Federal Institute of
Technology - Lausanne (EPFL), Switzerland and at the Computer Science
Department of the University of Cyprus, Cyprus. He obtained his Ph.D.
in Computation in 1998 from the Department of Computation, UMIST,
Manchester, UK. His research interests include keyword search and
ranking in relational databases.
| Other Presentations Web: http://www.cs.uc y.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Christos Kapoutsis
Affiliation: University of Cyprus,
Cyprus
Category: Research Seminar
Location: Room 147, Building 12 Faculty of
Pure and Applied Sciences, New Campus (map)
Date: Tuesday, February 16th, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.kapoutsis
Abstract: This is a talk on the size complexity of two-way finite automata. We will present the central open
problem in the area, explain a motivation behind it, recall its early history, and introduce some of
the concepts used in its study. We will then sketch a possible future, describe a natural systematic
way of pursuing it, and record some of the progress that has been achieved so far. We will add
little to what is already known ---only exposition, terminology, and questions.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Charis Poullis
Affiliation: University of Cyprus,
Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of
Pure and Applied Sciences, New Campus (map)
Date: Friday, February 12th, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.poullis
Abstract:
In recent years there has been an increasing demand for applications which
employ miniature representations of the real world to recreate realistic and immersive virtual
environments. Many applications ranging
from computer graphics and virtual reality, to Geographical Information
Systems have already successfully
used real world representations derived from the combination of multi-sensory
data captured from aerial or
satellite imagery and LiDAR(Light Detection and Ranging) scanners. However,
despite their widespread and successfull application, the creation of such realistic 3D content remains
a complex, time-consuming, expensive and labor-intensive task. In fact, the creation of models is still
widely viewed as a specialized art, requiring personnel with extensive training and experience to produce
useful models. In this research, we focus on historically-difficult problems in creating large-
scale (city size) scene models from sensor data, including rapid extraction and modeling of geometry models,
re-production of high-quality scene textures, and fusion and completion of the geometry and texture data to
produce photorealistic 3D scene models. We address the current problems and limitations of state of the
art techniques and present our solutions, including a fully automatic technique for extraction of polygonal
3D models from LiDAR data, and a flexible texture blending technique for generation of photorealistic
textures from multiple optical sensor resources. The result is a unified(multi-sensory),
comprehensive(structure and appearance) and immersive representation of large-scale areas of the real world.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Dimitrios Tsoumakos
Affiliation: University of Cyprus, Cyprus
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Tuesday, February 9th, 2010
Time: 15:00-16:30 EET
Host: Yannis Dimopoulos (yannis AT cs.ucy.ac.cy) and George Pallis (gpallis AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.tsoumakos
Abstract:
Grid technology has achieved significant advances in the past few
years with a plethora of prestigious organisations contributing to
middleware that opens the horizons for new exploitation opportunities.
However, this potential exploitation has not yet been seen to
materialise in emerging applications. The use of Grid technology is
still confined mainly within scientific applications, developed by
scientific organisations, being experts in Grid principles. GREDIA
(FP6 34363 - Grid enabled access to rich media content) addresses this
problem with the provision of a Grid application development platform.
In this talk I will describe the general goals of the GREDIA project
and specifically describe the design of the data/metadata layers of
its middleware component.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Josephina Antoniou
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Monday, January 18th, 2010
Time: 9:30-10:30 EET
Host: Andreas Pitsillides (Andreas.Pitsillides AT ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2010.antoniou
Abstract:
Next Generation Communication Networks employ the idea of convergence, where heterogeneous access technologies may co-exist. Since in this new network model, a user (or a set of users) may be served by any (one or many) of the multiple, available access networks, the emergence of a new resource management mechanism is motivated to handle the selection of the most appropriate access network(s) for supporting a user request for a service (or a particular service demand). This new mechanism is known as Network Selection.
The triggering and execution of the Network Selection mechanism becomes a challenging task due to the heterogeneity of the entities involved, i.e. the user(s) and the access network(s). This heterogeneity results in different and often conflicting interests for these entities. Since cooperation between these entities, if achieved, is expected to be beneficial, we pose the following question: Can cooperation be motivated in interactive situations related to Network Selection, and if yes, is it beneficial for the interacting entities? In pursue of answering this question, this thesis isolates and studies three different interactive situations between user(s) and network(s) in a heterogeneous environment, which are related to Network Selection and proposes appropriate modes of behaviour that allow the interacting entities to achieve own satisfaction, despite their conflicting interests.
Short Bio:
Josephina Antoniouc.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD Defense entitled:
Speaker: Nearchos Paspallis
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus (map, directions)
Date: Wednesday, September 30th, 2009
Time: 10:00-11:00 EET
Host: George A. Papadopoulos (george AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2009.paspallis
Abstract:
Driven by the proliferation of mobile and pervasive computing, there is a growing demand for context-aware, self-adaptive applications. Such applications benefit users by dynamically adjusting their offered services to the highly dynamic context which characterizes mobile and pervasive computing environments. To achieve this kind of sophistication, however, such applications must be capable of sensing the context, and autonomously reacting upon their knowledge on it. However, enabling this kind of behavior inevitably results in a measurable increase to the complexity of the underlying software.
This presentation discusses the challenges in developing context-aware software and compiles an extensive list of requirements that need to be addressed. It then proposes a component-based development approach that facilitates reusability and eases the task of designing and implementing context-aware applications using separation-of-concerns. The development methodology is extended with a Model-driven development approach and is supported by a pluggable and modular middleware architecture which optimizes the resource consumption in run-time. The proposed approach is evaluated both quantitatively and qualitatively.
Short Bio:
Nearchos Paspallis is a PhD Candidate at the Department of Computer Science, University of Cyprus. He received an MSc in Computer Science from the University of California, Santa Barbara, and a BSc in Computer Engineering and Informatics from the University of Patras.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Dimitrios D. Vergados
Affiliation: University of Piraeus, Greece
Category: Invited Course Lecture
Location: Room 005, Building XWD, New Campus (map)
Date: Tuesday, September 22nd, 2009
Time: 10:30-12:00 EET
Host: Vasos Vassiliou (vasosv AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2009.vergados
Abstract:
Ad-hoc networks rely on multihop transmission among the nodes on the same channel. Possible simultaneous transmissions may cause collisions, whenever transmitting nodes have a common destination node in their interference range. To avoid these collisions while minimizing the frame length, the NP-complete Broadcast Scheduling Problem (BSP) should be approximated. This is usually done by interpreting the BSP into a corresponding Graph Coloring Problem. In this talk, I will presented a proposed algorithm that tries to approximate the BSP, using an interference vector. Additionally, the node ordering policies used for scheduling are evaluated in terms of frame length and execution time. Simulation results show that the proposed algorithm has smaller execution time than the ones using graph coloring, and decreasing degree ordering results to the best frame length.
Short Bio:
Dimitrios D. Vergados was born in Athens, Greece in 1973. He is a Lecturer in the Department of Informatics, University of Piraeus. He has held position as a Lecturer in the University of the Aegean, Department of Information and Communication Systems Engineering. He received his B.Sc. from the University of Ioannina and his Ph.D. from the National Technical University of Athens, Department of Electrical and Computer Engineering. His research interests are in the area of Communication Networks (Wireless Broadband Networks, Sensor Networks, Ad-hoc Networks, WLANs, IMS, Mesh Networks), Neural Networks, GRID Technologies, and Computer Vision. He has participated in several projects funded by EU and National Agencies and has several publications in journals, books and conference proceedings. He has served in technical program committees of several conferences. He is a guest editor and a reviewer in several journals.
| Other Presentations Web: http://www.cs.ucy.ac.cy/colloquium/presentations.php | |
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The Department of Computer Science at the University of Cyprus cordially invites you to the Invited Course Lecture entitled:
Speaker: Dr. Andrew Philippides
Affiliation: University of Sussex, UK
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Monday, September 21th, 2009
Time: 10:00-13:00 EET
Host: Christos Schizas (schizas AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2009.phillipides2
Abstract:
Visual homing, the ability to get back to a nest or goal location using visual landmarks, is a vital capability for insects. Insects appear to achieve this behaviour through a process of image-matching in which the direction to nest or goal is recovered from the difference between the view from their current position and a view or 'snapshot' stored at the nest or goal position. Since this type of view-based homing was first proposed, simple, snapshot-type models have demonstrated successful homing performance over a range of environments and robotic platforms. In this talk, I will introduce the field of view-based homing and review the main snapshot-type models. I will then discuss three aspects of visual homing that I am currently working on: how the snapshot is learnt and used; what visual features make up the snapshot; and over what range a single snapshot is sufficient for homing.
I will first discuss recent work testing snapshot models in several natural environments. While it is known that insects use image matching to return home, the extent of the area within which insects can navigate in natural environments using a single snapshot has yet to be determined. This information is necessary before we can interpret data coming from the radar tracking of homing bees which some authors have used to conclude that a map-like representation is required for navigation over bees' natural foraging range. I will show that the information for homing can exist in natural environments over large-scales (100s of metres) and where in the world this information is coming from.
I will then discuss the results of this work in the light of both the natural visual ecology and natural behaviour of Australian Desert Ants as they navigate between nest and a feeder. Recent work by a colleague at Sussex has shown that the outline of objects against the skyline is sufficient for these ants to recover the direction home from the feeder. Here I will show that the skyline contains enough information for visual homing algorithms to function successfully. I will then discuss how the environment limits the range of a single snapshot, but that this range can be increased by considering the ant's required behaviour - route following - which leads to a simpler model of navigation.
I will conclude by discussing bumblebee learning flights and how this remarkable innate behaviour facilitates view-based homing. To enable them to locate their inconspicuous nest entrances using local visual landmarks, bees and wasps perform orientation or learning flights when they leave the nest to forage. This behaviour includes a number of stereotyped flight manoeuvres which appear to be structured to mediate the active acquisition of visual information. We have recorded and analysed bumblebee learning flights in multiple visual environments. Here I will present several flight strategies that bumblebees use to learn, and later find, the nest location during outward and return flights, respectively.
Short Bio:
Andrew Philippides is a Lecturer II within the Department of Informatics in the University of Sussex, where he is a member of the Sussex insect Navigation Group within the Centre for Computational Neuroscience and Robotics. He gained his doctorate in neuroscience at Sussex studying diffusible neuromodulators in real and artificial nervous systems and has been at Sussex ever since. While continuing his research into neuromodulation in networks, he also studies visual navigation in insects using a combination of behavioural experiments, mathematical and robotic modelling.
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The Department of Computer Science at the University of Cyprus cordially invites you to the Short Duration Course entitled:
Speaker: Dr. Andrew Philippides
Affiliation: University of Sussex, UK
Category: Invited Course Lecture
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus (map)
Date: Friday, September 18th, 2009
Time: 15:00-18:00 EET
Host: Christos Schizas (schizas AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2009.phillipides
Abstract:
The discovery of freely diffusing gaseous neurotransmitters, such as nitric oxide (NO), in biological nervous systems has radically altered the traditional connectionist picture of the brain. A type of artificial neural network (ANN) inspired by such gaseous signalling, the GasNet, has previously been shown to be more evolvable than traditional ANNs when used as an artificial nervous system in an evolutionary robotics setting. In this context evolvability means consistent speed to very good solutions - here, appropriate sensorimotor behaviour-generating systems. Inspired by recently discovered features of NO signalling in brains, several GasNet variants have been produced which further increase evolvability.
Subsequent work aiming to explain these results asked to what extent the coupling between the GasNet's two signalling mechanisms, one "chemical" and one "electrical", can explain the differences in network performance. The results of these investigations can be crystallised into three linked hypotheses on why the GasNets evolve faster:
1. The action of gas over multiple different timescales from the electrical activity introduces rich dynamics which can be exploited
2. The spatial embedding of the networks serves to (flexibly) couple two interacting signalling systems
3. The particular modulatory effects are key to evolvability
Interestingly, these three factors can be found in an oft-cited definition of neuromodulation:
"Any communication between neurons caused by the release of a chemical that is either not fast, or not point-to-point or not simply excitation or inhibition" (Katz, 1999)
In this talk, I will introduce the GasNet and its use as a controller for autonomous robots. I will present a summary of experiments which highlight the increased evolvability of the GasNet and which suggest the reasons lie in the factors highlighted above. I will then attempt to disentangle which of the abstracted elements of neuromodulation added into standard ANNs aid evolvability, by examining the hypotheses above in the light of various empirical studies, focusing on a comparison of variants of the basic GasNet formed by imposing constraints on spatial, temporal and modulatory properties.
Short Bio:
Andrew Philippides is a Lecturer II within the Department of Informatics in the University of Sussex, where he is a member of the Sussex insect Navigation Group within the Centre for Computational Neuroscience and Robotics. He gained his doctorate in neuroscience at Sussex studying diffusible neuromodulators in real and artificial nervous systems and has been at Sussex ever since. While continuing his research into neuromodulation in networks, he also studies visual navigation in insects using a combination of behavioural experiments, mathematical and robotic modelling.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD defense entitled:
Speaker: Mr. George P. Tsouloupas
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus, University of Cyprus (map)
Date: Monday, May 11th, 2009
Time: 13:00 - 14:00 EET
Host: Marios Dikaiakos (mdd AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2009.tsouloupas
Abstract:
Over the recent years the area of Grid Computing has seen an astonishing growth. Grid infrastructures have become the platform of choice for large- scale eScience. The world's largest Grid infrastructure - EGEE - currently comprises 300 sites distributed around the world, petabytes of storage capacity and CPU's in excess of 80,000. The different computing resources in these heterogeneous infrastructures gather impressive and unprecedented computational potential, yet, in order to utilize them, users need mechanisms for selecting the right resources for the right job. Users and Virtual Organization administrators also need end-to-end mechanisms to evaluate the performance of resources and audit resources according to their advertised performance. This can be a complicated process, and when large infrastructures are involved, it becomes unmanageable and prohibitively tedious in the absence of specialized tools.
Performance ranking in a large, shared, heterogeneous and dynamic environment is a complex task because it needs to be done in an efficient and unobtrusive way. At the same time, it has to address many different types of application that come from several Virtual Organizations.
This thesis presents a methodology for putting correct, meaningful and contextualized performance information at the user's disposal, thus facilitating the ranking of computational resources based on customizable criteria. Contextualization is achieved by enriching the measurements with metadata about when, where, how and in many cases under what circumstances the measurement is obtained. The thesis proceeds to propose a userdriven approach for ranking resources by employing custom ranking functions.
GridBench is an extensible tool that has been designed and implemented in the context of this thesis and along the lines of this methodology. It allows for context-augmented performance evaluation using several types of benchmarks, ranging from synthetic microbenchmarks to real-world parallel applications. It demonstrates how the evaluation and ranking process, an otherwise complicated and tedious task, can be simplified. Grid- Bench features a user-friendly graphical interface that facilitates the invocation of tests and benchmark and the collection, archival and analysis of results. A primary component, SiteRank, enables the interactive user-driven creation of custom ranking functions and provides a ranking of resources according to a users' specification.
The methodology and tools are applied through several experiments to the largest production Grid infrastructure in existence today. Among the arguments of the thesis is that the use of evidence-based "measured" data, in contrast to the "quoted" data advertised in information services by resource owners, is imperative. The existing de facto approach for selecting resources according to performance is shown to be insufficient and unreliable.
Short Bio:
George P. Tsouloupas is a PhD Candidate at the Department of Computer Science, University of Cyprus.
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The Department of Computer Science at the University of Cyprus cordially invites you to the presentation entitled:
Speaker: Mr. Michele Mazzucco
Affiliation: University of Newcastle, UK
Category: Presentation
Location: Room 147, Building 12 Faculty of Pure and Applied Sciences, New Campus, University of Cyprus (map)
Date: Monday, March 16th, 2009
Time: 15:00 - 16:00 EET
Host: Marios Dikaiakos (mdd AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2009.mazzucco
Abstract:
As IT systems are becoming more important everyday, one of the main concerns is that users may face major breakdowns and eventually incur major costs if computing systems do not meet the expected performance requirements. Even with the adoption of data centers as the hub of IT organizations and provider of business efficiencies the problems are not over because it is extremely difficult for service providers to meet the promised performance guarantees in spite of unpredictable user demand. One possible approach is the adoption of Service Level Agreements (SLAs), contracts that specify a level of performance that must be met and remedies in case of failure.
In this talk I will address some of the performance problems arising when IT companies sell the service of running 'jobs' subject to Quality of Service (QoS) constraints. QoS issues can be addressed from several perspectives, such as an engineering point of view (i.e., how to provide a service subject to performance constraints) or a semantic one (i.e., how to dynamically discover or select service with tight performance needs, or how to negotiate QoS requirements at run time). Here I will focus on the former one. First, I will define the problem in terms of an utility function to maximize, then I will present dynamic allocation and admission policies for enterprise data centers as well as an autonomic architecture for service provisioning.
Short Bio:
Michele Mazzucco received is BSc and MSc from University of Bologna (Italy) in 2003 and 2005 respectively. From 2006 to 2008 he worked as a Research Associate at the Newcastle University (UK) on a BT founded project. He is completing his PhD under the supervision of Prof. Isi Mitrani with a thesis focused on the design of adaptive service provisioning systems (part of the thesis is subject to an European Union patent application). Since March 2008 he is one of the committers at the Apache Software Foundation.
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD defense entitled:
Speaker: Mr. Wei Xing
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus, University of Cyprus (map)
Date: Friday, March 13th, 2009
Time: 13:00 - 14:00 EET
Host: Marios Dikaiakos (mdd AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2009.xing
Abstract:
Ontologies are a key technology for resolving the problem of information heterogeneity. A number of ontology based information integration systems has been developed that support information management tasks. However almost all of those systems rely on a number of assumptions about the nature of environment they are used in. One of these assumptions is that the domain is more or less static. In many realistic application scenarios for ontology based information systems, however, environments are highly dynamic. This is especially true to manage heterogeneous information in large scale distributed systems, such as Grids, cloud computing. In such environments, a number of issues are raised when applying an ontology based information integration approach for information management, because of changing information, changing ontology, and changing information sources.
This dissertation studies a key issue, semantic information dynamicity management in a large scale distributed environment. In our work we proposed an Active Ontology (ActOn) information model for representing dynamic information by strengthening ontology technology with a new dynamic management element. Based on the ActOn model, we developed a lifetime control and information source selection mechanisms to ensure the accurateness and consistence of the information that represented using ActOn model. Lifetime control is important for information quality. In fact, inaccurate information is an even bigger problem than missing information, because services or consumers relying on information will produce wrong actions or wrong results without warning. The selection of a suitable information source for information retrieving is particular important as the high alternative and redundancy of the available information sources in a large scale distributed environment. The idea behind ActOn model is simple: information is represented as instantiation of classes of ActOn domain ontology. In particular, it allows the value of dynamic part of information can be interpreted as an executable query; the execution of the query is controlled by its lift-time. The ActOn model comprises two kinds of ontologies, domain ontology and information source ontology, from which one can retrieve metadata to instantiate the model. A new ontology element DObject is particularly designed to link the domain ontology and the information source ontology, which in turn enable those ActOn instances be generated (or updated) dynamically in cope with the changes in a distributed environment. The life-time control mechanism is used to manage (update) dynamic information. The information source selection mechanism is used to select a suitable information source against the query execution from multiple information source candidates during the information life cycle management. To illustrate the usefulness of our ActOn model, a design and development of an ActOnbased information service for EGEE Grid is presented. The main difference with respect to other Grid information services is that it incorporate two ActOn specific modules that are not commonly found in others: a semantic information cache with lifetime management, which provides fast access to information that has been already integrated and materialized and which is still valid, and an information source selector, which is used during the generation of the execution plan for retrieving information from the information sources and allows system to adapt to changing conditions of the EGEE Grid infrastructure and to add new information sources easily.
Another important aspect of our research is the study of information quality in a large scale distributed environment. We proposed a fair systematic approach to measure information quality of different information services deployed in a large scale distributed environment. Our proposed evolution framework mainly tests three key metrics of information: information completeness, consistency, and accessibility. We conducted experiments to compare and analysis two EGEE deployed information services (BDII and RGMA) and the ActOn information service on EGEE production testbed.
Short Bio:
Wei Xing is a PhD Candidate at the Department of Computer Science, University of Cyprus.
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The Department of Computer Science at the University of Cyprus cordially invites you to the demonstration entitled:
Speaker: Mr. Louis Prokopiou
Affiliation: Library, University of Cyprus
Category: Demonstration
Location: Room 021, Building 12 Faculty of Pure and Applied Sciences, New Campus, University of Cyprus (map)
Date: Friday, March 6th, 2009
Time: 15:00 - 16:00 EET
Host: Marios Dikaiakos (mdd AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2009.prokopiou
Abstract:
Στην παΟουσίαση αυτή ΞΈΞ± Ξ³Ξ―Ξ½ΞµΞΉ αναφοΟΞ¬ στον Ο„ΟΟπο αναζήτησης σε βάσεις δεδομΞνων βιβλιογΟαφικής Ο†Οσεως (Scopus, WebofScience, Googlescholar ΞΊ.Ξ±.) ΞΌΞµ ΟƒΞΊΞΏΟ€Ο Ο„ΞΏΞ½ ΞµΞ½Ο„ΞΏΟ€ΞΉΟƒΞΌΟ Ξ·Ξ»ΞµΞΊΟ„ΟΞΏΞ½ΞΉΞΊΞΏΟ Ο…Ξ»ΞΉΞΊΞΏΟ (Ξ¬ΟΞΈΟων, βιβλίων, τεχνικΟΞ½ ΞµΞΊΞΈΞσεων) ΞΊΞ±ΞΉ στη συνΞχεια διαχείΟισής του ΞΌΞµ ΞµΟγαλεία διαχείΟισης βιβλιογΟαφίας ΞΊΞ±ΞΉ συγκεκΟΞΉΞΌΞΞ½Ξ± ΞΌΞµ το RefWorks. Το RefWorks ΞµΞ―Ξ½Ξ±ΞΉ ΞΞ½Ξ± ΞµΟγαλείο ΞΏΟγάνωσης ΞΊΞ±ΞΉ διαχείΟισης βιβλιογΟαφίας ΞΊΞ±ΞΉ βιβλιογΟαφικΟΞ½ αναφοΟΟΞ½. Ξ Ξ±ΟΞχει την δυνατΟτητα δημιουΟΞ³Ξ―Ξ±Ο‚ Ο€Οοσωπικής βάσης δεδομΞνων, εισάγοντας βιβλιογΟαφικΞΟ‚ αναφοΟΞΟ‚ απευθείας Ξ±Ο€Ο Ξ΄ΞΉΞΊΟ„Ο…Ξ±ΞΊΞΟ‚ βάσεις βιβλιογΟαφικΟΞ½ δεδομΞνων Ξ® χειΟωνακτικά, Ξ±Ο€Ο ΞΊΞ±Ο„Ξ¬Ξ»Ξ»Ξ·Ξ»Ξ± ηλεκτΟΞΏΞ½ΞΉΞΊΞ¬ Ξ±Οχεία ΞΊΞµΞΉΞΌΞΞ½ΞΏΟ…. Επίσης παΟΞχει την δυνατΟτητα ΞΌΞΏΟφοποίησης των αναφοΟΟΞ½ Ξ±Ο…Ο„ΟΞ½ (MLA, APA, Chicago Manual of Style, Turabian, ΞΊ.Ξ±.) ΞΊΞ±ΞΉ Ο‡Οήσης τους Ξ³ΞΉΞ± την δημιουΟΞ³Ξ―Ξ± βιβλιογΟαφιΟΞ½ σε επιστημονικά συγγΟάμματα, Ξ¬ΟΞΈΟΞ±, ΞµΟγασίες κλπ. Στην παΟουσίαση ΞΈΞ± Ξ³Ξ―Ξ½ΞµΞΉ αναλυτική επίδειξη των λειτουΟΞ³ΞΉΟΞ½ του ΞµΟγαλείου Οπως εισαγωγή ΞΊΞ±ΞΉ εξαγωγή αναφοΟΟΞ½ στην εσωτεΟΞΉΞΊΞ® βάση του Refworks, ΞΏΟγάνωση ΞΊΞ±ΞΉ διαχείΟιση αναφοΟΟΞ½, ετοιμασία ΞΊΞ±ΞΉ συγγΟαφή βιβλιογΟαφίας Ξ³ΞΉΞ± ΞµΟγασίες ΞΊΞ±ΞΉ δημιουΟΞ³Ξ―Ξ± παΟαπομπΟΞ½ (citation) σε ΞΊΞµΞ―ΞΌΞµΞ½Ξ± ΞΌΞµ Ξ±Ο…Ο„Οματη ΞµΞ½Ξ·ΞΌΞΟωση της τελικής βιβλιογΟαφικής λίστας.
Short Bio:
ΠΛοΟΞ·Ο‚ Ξ Οοκοπίου ΞµΞ―Ξ½Ξ±ΞΉ υπεΟΞΈΟ…Ξ½ΞΏΟ‚ του Ξ“Οαφείου ΔιαχείΟισης ΞΟγων της Ξ’Ξ Ξ ΞΊΞ±ΞΉ Ξ±Ο€Οφοιτος του τμήματος ΕπιστημΟΞ½ της Αγωγής του Πανεπιστημίου ΞΟΟ€ΟΞΏΟ…. Για πεΟισσΟτεΟΞµΟ‚ πληΟοφοΟΞ―ΞµΟ‚ επικοινωνήστε ΞΌΞµ το ΛοΟΞ· Ξ Οοκοπίου στο 22892016 Ξ® στην ηλεκτΟΞΏΞ½ΞΉΞΊΞ® διεΟθυνση Prokopiou.louis@ucy.ac.cy
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The Department of Computer Science at the University of Cyprus cordially invites you to the PhD defense entitled:
Speaker: Mr. Kyriakos Stavrou
Affiliation: University of Cyprus, Cyprus
Category: PhD Defense
Location: Room 148, Building 12 Faculty of Pure and Applied Sciences, New Campus, University of Cyprus (map)
Date: Friday, January 24th, 2009
Time: 11:00 - 12:00 EET
Host: Pedro Trancoso (pedro AT cs.ucy.ac.cy)
URL: http://www.cs.ucy.ac.cy/colloquium/presentations.php#cs.ucy.pres.2009.stavrou
Abstract:
This work presents the TFlux (Thread Flux) Parallel Processing Platform, a complete system that offers an efficient dataflow-like thread-based model of execution, the Data-Driven Multithreading (DDM), to its users using commodity components, i.e. unmodified Operating System, unmodified compiler and unmodified ISA hardware making it applicable to off-the-shelf systems. TFlux provides a complete solution from the programming toolchain to the hardware implementation. The abstraction layer TFlux exports to its users hides all the details of the underlying machine allowing different hardware configurations to support its model of execution transparently to the programmer.
The user of TFlux can develop applications using a set of simple but powerful compiler directives. Then the TFlux-C-Preprocessor coverts this code to an ANSI C program that includes the Runtime Support for TFlux and all calls to the system’s scheduler. This code can be compiled with a commodity C compiler resulting in a binary that is executable by any commodity Operating Systems on any commodity CPU processors. The layered design of TFlux has been tested on different Unix-based multiprocessor systems. Moreover, this design enabled the porting of TFlux to different machines with minimum effort.
In this work, two TFlux implementations are presented: TFluxHard and TFluxSoft. For TFluxHard the thread Scheduler is implemented as a hardware unit whereas for TFluxSoft, the Scheduler’s functionality is provided at the software level. As such, TFluxHard is applicable to systems that offer the ability to augment the machine with a small hardware module while TFluxSoft is directly applicable to any existing off-the-shelf systems. To evaluate the TFlux implementations, a benchmark suite based on existing and synthetic applications was developed. The applications in this suite were carefully chosen in order to have different characteristics both in terms of their dynamic behavior and complexity of their dataflow graph. Although for most applications the performance of the two implementations is close, TFluxHard shows an advantage over TFluxSoft arising from offloading the Scheduler’s functionality to the hardware module.
In addition, the experimental results also show that TFlux is able to exploit better the parallelism for applications with complex dependency graphs, compared with traditional parallel programming model approaches. Overall, TFlux proves to be a platform that allows applications to efficiently exploit the available parallelism. This is achieved by supporting dataflow-like thread scheduling in commodity multicore/multiprocessor systems.
Short Bio:
Kyriakos Stavrou is a PhD Candidate at the Department of Computer Science, University of Cyprus.
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