Temporal disjunctive logic programming

In this paper we introduce the logic programming languageDisjunctive Chronolog which combines the programming paradigms of temporal and disjunctive logic programming. Disjunctive Chronolog is capable of expressing dynamic behaviour as well as uncertainty, two notions that are very common in a variety of real systems. We present the minimal temporal model semantics and the fixpoint semantics for the new programming language and demonstrate their equivalence. We also show how proof procedures developed for disjunctive logic programs can be easily extended to apply to Disjunctive Chronolog programs. Manolis Gergatsoulis, Ph.D.: He received his B.Sc. in Physics in 1983, the M.Sc. and the Ph.D. degrees in Computer Science in 1986 and 1995 respectively all from the University of Athens, Greece. Since 1996 he is a Research Associate in the Institute of Informatics and Telecommunications, NCSR ‘Demokritos’, Athens. His research interests include logic and temporal programming, program transformations and synthesis, as well as theory of programming languages. Panagiotis Rondogiannis, Ph.D.: He received his B.Sc. from the Department of Computer Engineering and Informatics, University of Patras, Greece, in 1989, and his M.Sc. and Ph.D. from the Department of Computer Science, University of Victoria, Canada, in 1991 and 1994 respectively. From 1995 to 1996 he served in the Greek army. From 1996 to 1997 he was a visiting professor in the Department of Computer Science, University of Ioannina, Greece, and since 1997 he is a Lecturer in the same Department. In January 2000 he was elected Assistant Professor in the Department of Informatics at the University of Athens. His research interests include functional, logic and temporal programming, as well as theory of programming languages. Themis Panayiotopoulos, Ph.D.: He received his Diploma on Electrical Engineering from the Department of Electrical Engineering, National Technical Univesity of Athens, in 1984, and his Ph.D. on Artificial Intelligence from the above mentioned department in 1989. From 1991 to 1994 he was a visiting professor at the Department of Mathematics, University of the Aegean, Samos, Greece and a Research Associate at the Institute of Informatics and Telecommunications of “Democritos” National Research Center. Since 1995 he is an Assistant Prof. at the Department of Computer Science, University of Piraeus. His research interests include temporal programming, logic programming, expert systems and intelligent agent architectures.     

Early Estimation of Users’ Perception of Software Quality

This paper presents a methodology for estimating users’ opinion of the quality of a software product. Users’ opinion changes with time as they progressively become more acquainted with the software product. In this paper, we study the dynamics of users’ opinion and offer a method for assessing users’ final perception, based on measurements in the early stages of product release. The paper also presents methods for collecting users’ opinion and from the derived data, shows how their initial belief state for the quality of the product is formed. It adapts aspects of Belief Revision theory in order to present a way of estimating users’ opinion, subsequently formed after their opinion revisions. This estimation is achieved by using the initial measurements and without having to conduct surveys frequently. It reports the correlation that users tend to infer among quality characteristics and represents this correlation through a determination of a set of constraints between the scores of each quality characteristic. Finally, this paper presents a fast and automated way of forming users’ new belief state for the quality of a product after examining their opinion revisions. Dimitris Stavrinoudis received his degree in Computer Engineering from Patras University and is a Ph.D. student of Computer Engineering and Informatics Department. He worked as a senior computer engineer and researcher at the R.A. Computer Technology Institute. He has participated in research and development projects in the areas of software engineering, databases and educational technologies. Currently, he works at the Hellenic Open University. His research interests include software quality, software metrics and measurements. Michalis Xenos received his degree and Ph.D. in Computer Engineering from Patras University. He is a Lecturer in the Informatics Department of the School of Sciences and Technology of the Hellenic Open University. He also works as a researcher in the Computer Technology Institute of Patras and has participated in over 15 research and development projects in the areas of software engineering and IT development management. His research interests include, inter alia, Software Engineering and Educational Technologies. He is the author of 6 books in Greek and over 30 papers in international journals and conferences. Pavlos Peppas received his B.Eng. in Computer Engineering from Patras University (1988), and his Ph.D. in Computer Science from Sydney University (1994). He joined Macquarie University, Sydney, as a lecturer in September 1993, and was promoted to a senior lecturer in October 1998. In January 2000, he took up an appointment at Intrasoft, Athens, where he worked as a senior specialist in the Data Warehousing department. He joint Athens Information Technology in February 2003 as a senior researcher, and since November 2003 he is an associate professor at the Dept of Business Administration at the University of Patras. He also holds an adjunct associate professorship at the School of Computer Science and Engineering at the University of New South Wales. His research interests lie primarily within the area of Artificial Intelligence, and more specifically in logic-based approaches to Knowledge Representation and Reasoning with application in robotics, software engineering, organizational knowledge management, and the semantic web. Dimitris Christodoulakis received his degree in Mathematics from the University of Athens and his Ph.D. in Informatics from the University of Bonn. He was a researcher at the National Informatics Centre of Germany. He is a Professor and Vice President of Computer Engineering and Informatics Department of Patras University. Scientific Coordinator in many research and development projects in the followings sections: Knowledge and Data Base Systems, Very large volume information storage, Hypertext, Natural Language Technology for Modern Greek. Author and co-author in many articles published in international conferences. Editor in proceedings of conventions. Responsible for proofing tools development for Microsoft Corp. He is Vice Director in the Research Academic Computer Technology Institute (RACTI).     

A platform for virtual collaboration spaces and educational communities: the case of EVE

This paper presents the design, implementation and evaluation of EVE Community Prototype, which is an educational virtual community aiming to meet the requirements of a Virtual Collaboration Space and to support e-learning services. Furthermore, this paper describes the design and implementation of an integrated platform for Networked Virtual Environments, called EVE Platform, which supports the afore-mentioned educational community. This platform supports stable event sharing and creation of multi-user three dimensional (3D) places, H.323-based voice over IP services integrated in 3D spaces as well as multiple concurrent virtual worlds. Christos Bouras obtained his Diploma and PhD from the Department Of Computer Engineering and Informatics of Patras University (Greece). He is currently an Associate Professor in the above department. Also he is a scientific advisor of Research Unit 6 in Research Academic Computer Technology Institute (CTI), Patras, Greece. His research interests include Analysis of Performance of Networking and Computer Systems, Computer Networks and Protocols, Telematics and New Services, QoS and Pricing for Networks and Services, e-Learning Networked Virtual Environments and WWW Issues. He has extended professional experience in Design and Analysis of Networks, Protocols, Telematics and New Services. He has published 200 papers in various well-known refereed conferences and journals. He is a co-author of seven books in Greek. He has been a PC member and referee in various international journals and conferences. He has participated in R&D projects such as RACE, ESPRIT, TELEMATICS, EDUCATIONAL MULTIMEDIA, ISPO, EMPLOYMENT, ADAPT, STRIDE, EUROFORM, IST, GROWTH and others. Also he is member of experts in the Greek Research and Technology Network (GRNET), Advisory Committee Member to the World Wide Web Consortium (W3C), Member of WG3.3 and WG6.4 of IFIP, Task Force for Broadband Access in Greece, ACM, IEEE, EDEN, AACE and New York Academy of Sciences. Eleftheria Giannaka obtained her Diploma from the Informatics Department of the Aristotelian University of Thessaloniki (Greece) and her Masters Degree from the Computer Engineering and Informatics Department of Patras University. She is currently a PhD Candidate of the Department of Computer Engineer and Informatics of Patras University. Furthermore, she is working as an R&D Computer Engineer at the Research Unit 6 of the Computer Technology Institute in Patra (Greece). Her interests include Computer Networks, Virtual Networks, System Architecture, Internet Applications, Electronic Commerce, Database Implementation and Administration, Virtual Reality applications, Performance Evaluation and Programming. Alexandros Panagopoulos was born in Pyrgos, Greece, 1981. He obtained his Diploma, from the Computer Engineering and Informatics Department of Patras University (Greece). In 2000 he became a member of Research Unit 6 of the Computer Technology Institute (CTI). His interests include Computer Networks, Multiuser Virtual Environments, Telematics, and C/C++ and Java programming. Dr. Thrasyvoulos Tsiatsos obtained his Diploma, his Master's Degree and his PhD from the Computer Engineering and Informatics Department of Patras University (Greece). He is currently an R&D Computer Engineer at the Research Unit 6 of Computer Technology Institute, Patras, Greece. His research interests include Computer Networks, Telematics, Distributed Systems, Networked Virtual Environments, Multimedia and Hypermedia. More particular he is engaged in Distant Education with the use of Computer Networks, Real Time Protocols and Networked Virtual Environments. He has published nine papers in journals and 30 papers in well-known refereed conferences. He has participated in R&D projects such as OSYDD, RTS-GUNET, ODL-UP, VES, ODL-OTE, INVITE, VirRAD and EdComNet.     

Robust Quality Adaptation for Internet Video Streaming

Internet video streaming is a widely popular application however, in many cases, congestion control facilities are not well integrated into such applications. In order to be fair to other users that do not stream video, rate adaptation should be performed to respond to congestion. On the other hand, the effect of rate adaptation on the viewer should be minimized and this extra mechanism should not overload the client and the server. In this paper, we develop a heuristic approach for unicast congestion control. The primary feature of our approach is the two level adaptation algorithm that utilizes packet loss rate as well as receiver buffer data to maintain satisfactory buffer levels at the receiver. This is particularly important if receiver has limited buffer such as in mobile devices. When there is no congestion, to maintain best buffer levels, fine grain adjustments are carried out at the packet level. Depending on the level of congestion and receiver buffer level, rate shaping that involves frame discard and finally rate adaptation by switching to a different pre-encoded video stream are carried out. Additive increase multiplicative decrease policy is maintained to respond to congestion in a TCP- friendly manner. The algorithm is implemented and performance results show that it has adaptation ability that is suitable for both local area and wide area networks. E. Turhan Tunali received B.Sc. Degree in Electrical Engineering from Middle East Technical University and M.Sc. Degree in Applied Statistics from Ege University, both in Turkey. He then received D.Sc. Degree in Systems Science and Mathematics from Washington University in St. Louis, U.S.A. in 1985. After his doctorate study, he joined Computer Engineering Department of Ege University as an assistant professor where he became an associate professor in 1988. During the period of 1992–1994, he worked in Department of Computer Technology of Nanyang Technological University of Singapore as a Visiting Senior Fellow. He then joined International Computer Institute of Ege University as a Professor where he is currently the director. In the period of 2000–2001 he worked in Department of Computer Science of Loyola University of Chicago as a Visiting Professor. His current research interests include adaptive video streaming and Internet performance measurements. Dr. Tunali is married with an eighteen year old son. Aylin Kantarci received B.Sc., M.Sc. and Ph.D. degrees all from Computer Engineering Department of Ege University, Izmir, Turkey, in 1992, 1994 and 2000, respectively. She then joined the same department as an assistant professor. Her current research interests include adaptive video streaming, video coding, operating systems, multimedia systems and distributed systems. Nukhet Ozbek received B.Sc. degree in Electrical and Electronics Engineering from School of Engineering and M.Sc. degree in Computer Science from International Computer Institute both in Ege University, Izmir, Turkey. From 1998 to 2003 she worked in the DVB team of Digital R&D at Vestel Corporation, Izmir-Turkey that produces telecommunication and consumer electronics devices. She is currently a Ph.D. student and a research assistant at International Computer Institute of Ege University. Her research areas include video coding and streaming, multimedia systems and set top box architectures.     

An integrated edge detection method using mathematical morphology

This paper presents an edge detection method based on mathematical morphology. The proposed scheme consists of four steps: preprocessing, edge extraction, edge decision, and postprocessing. In the preprocessing step, a morphological central transformation is applied to remove noise. In the edge extraction and decision steps, a morphological edge extractor is designed to estimate the edge information of an image, and an edge decision criterion is followed to determine whether a pixel is an edge or not. In the postprocessing step, the morphological hit-or-miss transformation is utilized to improve the correctness of the detected edges. It is proved theoretically for the correctness and effectiveness for detecting ideal edges. Experimental results show that the proposed method works well on both artificial and real images. The text was submitted by the authors in English. Chin-Pan Huang was born in 1959 in Taiwan, Republic of China. He received the B.S. and M.S. degrees in electrical engineering from Chung Cheng Institute of Technology, Taiwan, in 1981 and in 1985, respectively. In 1996, he received the Ph.D. degree in electrical engineering from the University of Pittsburgh in the United States. From 1996 to 2002, he was an associate scientist of the Electronic System Division in Chung Shan Institute of Science and Technology. He then joined the Department of Computer and Communication Engineering at Ming Chuan University in August 2002 and is currently an assistant professor there. His recent research interests include data compression, computer vision, digital image processing, and pattern recognition. Ran-Zan Wang was born in 1972 in Fukien, Republic of China. He received his B.S. degree in computer engineering and science in 1994 and M.S. degree in electrical engineering and computer science in 1996, both from Yuan-Ze University. In 2001, he received his Ph.D. degree in computer and information science from National Chiao Tung University. In 2001–2002, he was an assistant professor at the Department of Computer Engineering at the Van Nung Institute of Technology. He joined the Department of Computer and Communication Engineering at Ming Chuan University in August 2002 and is currently an assistant professor there. His recent research interests include data hiding and digital watermarking, image processing, and pattern recognition. Dr. Wang is a member of the Phi Tau Phi Scholastic Honor Society.     

eInvoke: Secure e-Invoicing based on web services

Electronic Invoicing services (e-Invoicing) will have a pivotal role in all the stages of handling Value Added Tax (VAT) for European Member States. Through a systematic introduction of e-invoicing, tax administrators will be able to implement new tools and procedures to carry out alternative controls that are less intrusive on the trading partners. Nevertheless, successful European e-invoicing implementations need to be in compliance with the corresponding European Directive 2001/115/EC. Most contemporary e-Invoicing implementations are proprietary and based on EDI, thus demonstrating great deficiencies. This paper presents an open electronic invoicing system named eInvoke, based on XML, XML cryptography and Web Services, that addresses all security requirements imposed by the Directive. Our e-Invoicing system has been accepted by “CEN/ISSS e-Invoicing Focus Group on Standards and Developments on electronic invoicing relating to VAT Directive 2001/115/EC” and its summary appears in CEN 2003 report [13] (pg 79–85), forwarded to EC as a recommendation. Alexandros Kaliontzoglou holds a Degree in Electrical and Computer Engineering from the National Technical University of Athens (NTUA), Greece. Since 2001 he is a PhD candidate in the area of Network and Information Systems Security at the Telecommunications laboratory in the School of Electrical and Computer Engineering of NTUA. Since April 2000 he has been working for Expertnet S.A. as a security engineer specializing at Web Technologies and network applications, and he has been active both in European research projects in the 5th and 6th Framework Programme (eMayor, Intelcities, SELIS, Reshen, La Mer, TSEC, WebSig) and projects of the Greek private sector. His research interests focus in the area of IT Security, Service Oriented Architectures, Web Services, Software Engineering, e-Government, e-Commerce and Public Key Infrastructures. Pelagia Boutsi has obtained the Degree in Informatics from the University of Piraeus, Greece, in November 2001. Since April 2002, she is a PhD candidate in the area of Security Information at the Computer Science Department of University of Piraeus. Since September 2001 she is employed at Expertnet S.A. as member of the Technical Department. Her current research interests are in the fields of PKIs, XML and XML Security. She has participated in European research projects and projects of the private sector. Despina Polemi has obtained the Degree in Applied Mathematics from Portland State University(USA) in 1984, Ph.D. in Applied Mathematics (Coding Theory) from City University of New York (Graduate Center) in 1991. She held teaching positions (1984– 1995) in Queens College and Baruch College of City University of NewYork. From 1991 to 1996 was assistant professor (tenure track) in State University of New Yorkat Farmingdale in the department of Mathematics. During 1996–2002 she was an associate researcher in ICCS. From 2000 to 2003 she acted as President of the BoD in a security consulting company Expertnet (www.expertnet.net.gr) and technical manager of the company from 2000–2004. She nowa Professor in the University of Piraeus R&D department. Her current research interests are in the fields of cryptology, security and e-business. She has over ninety publications in the above areas. She has received many research grants from various organizations such as the Danish Research Foundation, MSI Army Research Office/Cornell University, IEEE, State University of New York (SUNY), and The Graduate School of City University of New York (CUNY). She has been project manager (PM)/technical manger (TM) in security projects of various programmes such as National Security Agency (NSA), Dr. Nuala McGann Drescher Foundation, Greek Ministry of Defense, INFOSEC TELEMATICS for Administrations (COSACC), the Fifth Framework IST Programme (HARP, BEE, SEED, WebSig, TSEC, CORAS, RESHEN, SEED, La Mer, SECRETS) and the 6FP (e-Mayor, Intelcities, BIOSEC, SELIS). She participated in the EC security projects of the programs COST, ACTS, and NATOs’ security projects. She is a member of IEEE. She serves as an evaluator, reviewer and expert in the European Commission and consultant for the FP6.     

Change-driven data flow image processing architecture for optical flow computation

Optical flow computation has been extensively used for motion estimation of objects in image sequences. The results obtained by most optical flow techniques are computationally intensive due to the large amount of data involved. A new change-based data flow pipelined architecture has been developed implementing the Horn and Schunk smoothness constraint; pixels of the image sequence that significantly change, fire the execution of the operations related to the image processing algorithm. This strategy reduces the data and, combined with the custom hardware implemented, it achieves a significant optical flow computation speed-up with no loss of accuracy. This paper presents the bases of the change-driven data flow image processing strategy, as well as the implementation of custom hardware developed using an Altera Stratix PCI development board.

Human-centered ontology engineering: The HCOME methodology

The fast emergent and continuously evolving areas of the Semantic Web and Knowledge Management make the incorporation of ontology engineering tasks in knowledge-empowered organizations and in the World Wide Web more than necessary. In such environments, the development and evolution of ontologies must be seen as a dynamic process that has to be supported through the entire ontology life cycle, resulting to living ontologies. The aim of this paper is to present the Human-Centered Ontology Engineering Methodology (HCOME) for the development and evaluation of living ontologies in the context of communities of knowledge workers. The methodology aims to empower knowledge workers to continuously manage their formal conceptualizations in their day-to-day activities and shape their information space by being actively involved in the ontology life cycle. The paper also demonstrates the Human Centered ONtology Engineering Environment, HCONE, which can effectively support this methodology. George VOUROS (B.Sc. Ph.D.) holds a B.Sc. in Mathematics, and a Ph.D. in Artificial Intelligence all from the University of Athens, Greece. Currently he is a Professor and Head of the Department of Information and Communication Systems Engineering, University of the Aegean, Greece, Director of the AI Lab and head of the Intelligent and Cooperative Systems Group (InCoSys). He has done research in the areas of Expert Systems, Knowledge management, Collaborative Systems, Ontologies, and Agent-based Systems. His published scientific work includes more than 80 book chapters, journal and national and international conference papers in the above-mentioned themes. He has served as program chair and chair and member of organizing committees of national and international conferences on related topics. Konstantinos KOTIS (B.Sc. Ph.D.) holds a B.Sc. in Computation from the University of Manchester, UK (1995), and a Ph.D. in Information Management from University of the Aegean, Greece (May, 2005). Currently, he is a member of the Intelligent and Cooperative Systems Group (InCoSys) and director of the Information Technology Department of the Prefecture of Samos, Greece. His research and published work concerns Knowledge management, Ontology Engineering and Semantic Web. He has lectured in several IT seminars and has served as member of program committees in international workshops.     

Hiding collaborative recommendation association rules

The concept of Privacy-Preserving has recently been proposed in response to the concerns of preserving personal or sensible information derived from data mining algorithms. For example, through data mining, sensible information such as private information or patterns may be inferred from non-sensible information or unclassified data. There have been two types of privacy concerning data mining. Output privacy tries to hide the mining results by minimally altering the data. Input privacy tries to manipulate the data so that the mining result is not affected or minimally affected. For output privacy in hiding association rules, current approaches require hidden rules or patterns to be given in advance [10, 18–21, 24, 27]. This selection of rules would require data mining process to be executed first. Based on the discovered rules and privacy requirements, hidden rules or patterns are then selected manually. However, for some applications, we are interested in hiding certain constrained classes of association rules such as collaborative recommendation association rules [15, 22]. To hide such rules, the pre-process of finding these hidden rules can be integrated into the hiding process as long as the recommended items are given. In this work, we propose two algorithms, DCIS (Decrease Confidence by Increase Support) and DCDS (Decrease Confidence by Decrease Support), to automatically hiding collaborative recommendation association rules without pre-mining and selection of hidden rules. Examples illustrating the proposed algorithms are given. Numerical simulations are performed to show the various effects of the algorithms. Recommendations of appropriate usage of the proposed algorithms based on the characteristics of databases are reported. Leon Wang received his Ph.D. in Applied Mathematics from State University of New York at Stony Brook in 1984. From 1984 to 1987, he was an assistant professor in mathematics at University of New Haven, Connecticut, USA. From 1987 to 1994, he joined New York Institute of Technology as a research associate in the Electromagnetic Lab and assistant/associate professor in the Department of Computer Science. From 1994 to 2001, he joined I-Shou University in Taiwan as associate professor in the Department of Information Management. In 1996, he was the Director of Computing Center. From 1997 to 2000, he was the Chairman of Department of Information Management. In 2001, he was Professor and director of Library, all in I-Shou University. In 2002, he was Associate Professor and Chairman in Information Management at National University of Kaohsiung, Taiwan. In 2003, he rejoined New York Institute of Technology. Dr.Wang has published 33 journal papers, 102 conference papers, and 5 book chapters, in the areas of data mining, machine learning, expert systems, and fuzzy databases, etc. Dr. Wang is a member of IEEE, Chinese Fuzzy System Association Taiwan, Chinese Computer Association, and Chinese Information Management Association. Ayat Jafari received the Ph.D. degree from City University of New York. He has conducted considerable research in the areas of Computer Communication Networks, Local Area Networks, and Computer Network Security, and published many technical articles. His interests and expertise are in the area of Computer Networks, Signal Processing, and Digital Communications. He is currently the Chairman of the Computer Science and Electrical Engineering Department of New York Institute of Technology. Tzung-Pei Hong received his B.S. degree in chemical engineering from National Taiwan University in 1985, and his Ph.D. degree in computer science and information engineering from National Chiao-Tung University in 1992. He was a faculty at the Department of Computer Science in Chung-Hua Polytechnic Institute from 1992 to 1994, and at the Department of Information Management in I-Shou University from 1994 to 2001. He was in charge of the whole computerization and library planning for National University of Kaohsiung in Preparation from 1997 to 2000, and served as the first director of the library and computer center in National University of Kaohsiung from 2000 to 2001 and as the Dean of Academic Affairs from 2003 to 2006. He is currently a professor at the Department of Electrical Engineering and at the Department of Computer Science and Information Engineering. His current research interests include machine learning, data mining, soft computing, management information systems, and www applications. Springer     

Virtual Private/Overlay Network Design With Traffic Concentration and Shared Protection

In this paper different algorithms are presented and evaluated for designing Virtual Private/Overlay Network (VPNs/VONs) over any network that supports resource partitioning e.g. ATM (Asynchronous Transfer Mode), MPLS (Multi Protocol Label Switching), or SDH/SONET (Synchronous Digital Hierarchy/Synchronous Optical Networking). All algorithms incorporate protection as well. The VPNs/VONs are formed by full mesh demand sets between VPN/VON endpoints. The service demands of VPNs/VONs are characterized by the bandwidth requirements of node-pairs (pipe-model).We investigated four design modes with three pro-active path based shared protection path algorithms and four heuristics to calculate the pairs of paths. The design mode determines the means of traffic concentration. The protection path algorithms use Dijkstras shortest path calculation with different edge weights. The demands are routed one-by-one, therefore the order in which they are processed matters.To eliminate this factor we used three heuristics (simulated allocation, simulated annealing, threshold accepting). We present numerical results obtained by simulation regarding the required total amount of capacity, the number of reserved edges, and the average length of paths.Péter Hegyi received MSc (2004) degree from the Budapest University of Technology and Economics, Hungary, where he is currently a PhD student at the Department of Telecommunications and Media Informatics. His research interests focus on design of intra- and inter-domain multilayer grooming networks and routing with protection. He has been involved in a few related projects (IKTA, ETIK, NOBEL).Markosz Maliosz is a researcher in the High Speed Networks Laboratory, Department of Telecommunication and Media Informatics at the Budapest University of Technology and Economics, where he received his MSc degree in Computer Science (1998). He has participated in projects concerning telecommunication services, network device control, Voice and Video over IP. His current research areas are Virtual Private Networking and traffic engineering in optical networks.Ákos Ladányi is a student at the Department of Telecommunications and Media Informatics at the Budapest University of Technology and Economics. His research interests focus on routing, network resilience, and combinatorial optimization.Tibor Cinkler has received MSc(94) and PhD(99) degrees from the Budapest University of Technology and Economics, Hungary, where he is currently Associate Professor at the Department of Telecommunications and Media Informatics. His research interests focus on routing, design, configuration, dimensioning and resilience of IP,MPLS, ATM, ngSDH and particularly of WR-DWDMbased multilayer networks. He is the author of over 60 refereed scientific publications and of 3 patents.     

A Framework for the Generation of Adaptive Courses Based on Semantic Metadata

This approach proposes the creation and management of adaptive learning systems by combining component technology, semantic metadata, and adaptation rules. A component model allows interaction among components that share consistent assumptions about what each provides and each requires of the other. It allows indexing, using, reusing, and coupling of components in different contexts powering adaptation. Our claim is that semantic metadata are required to allow a real reusing and assembling of educational component. Finally, a rule language is used to define strategies to rewrite user query and user model. The former allows searching components developing concepts not appearing in the user query but related with user goals, whereas the last allow inferring user knowledge that is not explicit in user model.John Freddy Duitama received his M.Sc. degree in system engineering from the University of Antioquia -Colombia (South America). He is currently a doctoral candidate in the GET – Institut National des Télécommunications, Evry France. This work is sponsored by the University of Antioquia, where he is assistant professor.His research interest includes semantic web and web-based learning systems, educational metadata and learning objects.Bruno Defude received his Ph.D. in Computer Science from the University of Grenoble (I.N.P.G) in 1986. He is currently Professor in the Department of Computer Science at the GET - Institut National des Télécommunications, Evry France where he leads the SIMBAD project (Semantic Interoperability for MoBile and ADaptive applications).His major field of research interest is databases and semantic web, specifically personalized data access, adaptive systems, metadata, interoperability and semantic Peer-to-peer systems with elearning as a privileged application area.He is a member of ACM SIGMOD.Amel Bouzeghoub received a degree of Ph.D. in Computer Sciences at Pierre et Marie Curie University, France.In 2000, she joined the Computer Sciences Department of GET-INT (Institut National des Telecommunications) at Evry (France) as an associate professor.Her research interests include topics related to Web-based Learning Systems, Semantic Metadata for learning resources, Adaptive Learning Systems and Intelligent Tutoring Systems.Claire Lecocq received an Engineer Degree and a Ph.D. in Computer Sciences respectively in 1994 and 1999. In 1997, she joined the Computer Sciences Department at GET-INT (Institut National des Télécommunications) of Evry, France, as an associate professor. Her first research interests included spatial databases and visual query languages. She is now working on adaptive learning systems, particularly on semantic metadata and user models.     

Joint Adoption of QoS Schemes for MPEG Streams

Indiscriminated packet discards strongly degrade the quality perceived by end users of MPEG video transmissions. This paper investigates different Quality of Service (QoS) schemes and the tradeoffs of jointly adopting such schemes to improve the delivery quality of an MPEG stream. From an analytical model, we evaluate the impact of frame losses on the quality of MPEG streams and on the waste of network resources. Our assessment considers issues such as the use of redundancy by applying a Forward Error Correction (FEC) scheme to tolerate losses, the changing of the compression factor in MPEG encoding, the unequal protection of MPEG frames in a Differentiated Services environment, and how to evaluate the impact of network losses onto application quality. Results provide predicted bounds on the quality to be expected by end users as well as guidelines on how to take the best advantage from the joint adoption of the investigated QoS schemes.Artur Ziviani received the B.Sc. degree in Electronics Engineering in 1998 and the M.Sc. degree in Electrical Engineering (with emphasis in Computer Networking) in 1999, both from the Federal University of Rio de Janeiro (UFRJ), Brazil. In December 2003, he received the Ph.D. degree in Computer Science from the University Pierre et Marie Curie (Paris 6), Paris, France, where he has also been a lecturer during the 2003–2004 academic year. Since September 2004, he is with the National Laboratory for Scientific Computing (LNCC), located in Petr'opolis, Brazil. His major research interests are quality of service, mobile and wireless computing, Internet measurements, and grid computing.Bernd E. Wolfinger has been with the Computer Science Department of Hamburg University since 1981, where he is presently heading the Telecommunications and Computer Networks (TKRN) Subdivision. He has degrees from Universit Claude-Bernard, Lyon (Matrise, 74), University of Karlsruhe (Diploma, Mathematics 75; Ph.D., Comp. Sc. 79) and has spent long-term sabbaticals at IBM Research, Yorktown Heights, N.Y. (85), Internat. Computer Science Institute, Berkeley, Ca. (91,96), as well as at Universit P. et M. Curie, Paris (01). Dr. Wolfinger is active in Networking research since 1975, has been responsible for numerous conference organizations and has served on a variety of TPCs. He has been an editor of books and special issues of journals and has published more than 100 papers in areas such as High-speed & Mobile Networks, Real-time Communications, Traffic Engineering, Modeling, Performance Evaluation and QoS Management.Jos'e Ferreira de Rezende received the B.Sc. and M.Sc. degrees in Electronic Engineering from the Universidade Federal do Rio de Janeiro (UFRJ) in 1988 and 1991, respectively. He received the Ph.D. degree in Computer Science from the Universit Pierre et Marie-Curie, Paris, France in 1997. He was an associate researcher at LIP6 (Laboratoire dInformatique de Paris 6) during 1997. Since 1998 he is an Associate Professor at UFRJ. His research interests are in distributed multimedia applications, multipeer communication, performance evaluation and QoS aspects of high-speed, wireless and sensor networks.Otto Carlos M.B. Duarte was born in Rio de Janeiro, Brazil, on October 23, 1953. He received the Electronic Engineer degree and the M.Sc. degree in Electrical Engineering from Universidade Federal do Rio de Janeiro, Brazil, in 1976 and 1981, respectively, and the Dr. Ing. degree from ENST/ Paris, France, in 1985. Since 1978 he is a Professor at Universidade Federal do Rio de Janeiro. From January 1992 to June 1993 he has worked at MASI Laboratory in Paris 6 University. In 1995, he has spent three months at International Computer Science Institute (ICSI) associated to the University of California at Berkeley. Presently, he is heading the computer network group (Grupo de Teleinformitica e Automao—GTA). His major research interests are in high speed communications, mobility, security and QoS guarantees.Serge Fdida is a professor at the University Pierre et Marie Curie (Paris) since 1991. He received the Doctorat de 3eme Cycle in 1984, and the Habilitation a Diriger des Recherches specializing in Modelling of computer networks in 1989 from the University Pierre et Marie Curie. From 1989 to 1995, he was a Full Professor to the University Rene Descartes (Paris). His research interests are in the area of high speed networking, pervasive communication, resource management and performance analysis. He is heading the Network and Performance group of the LIP6 Laboratory (CNRS-University of Paris 6). He was a Visiting Scientist at IBM Research during the 1990/91 academic year. He was the chairman (or co-chair) of the following events: IFIP Modelling Techniques and Tools 87, IFIP High Performance Networking 94 (HPN 94), Performance of Data Communication 95 (PCN 95) and European Conference on Multimedia Applications, Services and Techniques 97 (ECMAST 97), Networked Group Communication (NGC 99) and IFIP Networking 2000. He was the editor of the proceedings of these conferences and is the author of a book on performance evaluation and a book on Networking. He is involved in many research projects in High Performance Networking in France and Europe. He was heading the RHDM Action in France for 8 years and the COST264 Action in Europe (98 02). He belongs to the FP6 network of Excellence ENEXT. He is a senior member of IEEE, a member of ACM and also involved in two IFIP working groups on networking. He is also the Co-Director of EURONETLAB, a joint laboratory established in 2001, between University Paris 6, CNRS, THALES and 6WIND, developing research and development work on QoS Routers and Radio Routers.     

Estimating the number of clusters using a windowing technique

Clustering is the process of partitioning a set of patterns into disjoint and homogeneous meaningful groups (clusters). A fundamental and unresolved issue in cluster analysis is to determine how many clusters are present in a given set of patterns. In this paper, we present the z-windows clustering algorithm, which aims to address this problem using a windowing technique. Extensive empirical tests that illustrate the efficiency and the accuracy of the propsoed method are presented. The text was submitted by the authors in English. Basilis Boutsinas. Received his diploma in Computer Engineering and Informatics in 1991 from the University of Patras, Greece. He also conducted studies in Electronics Engineering at the Technical Education Institute of Piraeus, Greece, and Pedagogics at the Pedagogical Academy of Lamia, Greece. He received his PhD on Knowledge Representation from the University of Patras in 1997. He has been an assistant professor in the Department of Business Administration at the University of Patras since 2001. His primary research interests include data mining, business intelligence, knowledge representation techniques, nonmonotonic reasoning, and parallel AI. Dimitris K. Tasoulis received his diploma in Mathematics from the University of Patras, Greece, in 2000. He attained his MSc degree in 2004 from the postgraduate course “Mathematics of Computers and Decision Making” from which he was awarded a postgraduate fellowship. Currently, he is a PhD candidate in the same course. His research activities focus on data mining, clustering, neural networks, parallel algorithms, and evolutionary computation. He is coauthor of more than ten publications. Michael N. Vrahatis is with the Department of Mathematics at the University of Patras, Greece. He received the diploma and PhD degree in Mathematics from the University of Patras in 1978 and 1982, respectively. He was a visiting research fellow at the Department of Mathematics, Cornell University (1987–1988) and a visiting professor to the INFN (Istituto Nazionale di Fisica Nucleare), Bologna, Italy (1992, 1994, and 1998); the Department of Computer Science, Katholieke Universiteit Leuven, Belgium (1999); the Department of Ocean Engineering, Design Laboratory, MIT, Cambridge, MA, USA (2000); and the Collaborative Research Center “Computational Intelligence” (SFB 531) at the Department of Computer Science, University of Dortmund, Germany (2001). He was a visiting researcher at CERN (European Organization of Nuclear Research), Geneva, Switzerland (1992) and at INRIA (Institut National de Recherche en Informatique et en Automatique), France (1998, 2003, and 2004). He is the author of more than 250 publications (more than 110 of which are published in international journals) in his research areas, including computational mathematics, optimization, neural networks, evolutionary algorithms, and artificial intelligence. His research publications have received more than 600 citations. He has been a principal investigator of several research grants from the European Union, the Hellenic Ministry of Education and Religious Affairs, and the Hellenic Ministry of Industry, Energy, and Technology. He is among the founders of the “University of Patras Artificial Intelligence Research Center” (UPAIRC), established in 1997, where currently he serves as director. He is the founder of the Computational Intelligence Laboratory (CI Lab), established in 2004 at the Department of Mathematics of University of Patras, where currently he serves as director.     

Asynchronous action-reward learning for nonstationary serial supply chain inventory control

Action-reward learning is a reinforcement learning method. In this machine learning approach, an agent interacts with non-deterministic control domain. The agent selects actions at decision epochs and the control domain gives rise to rewards with which the performance measures of the actions are updated. The objective of the agent is to select the future best actions based on the updated performance measures. In this paper, we develop an asynchronous action-reward learning model which updates the performance measures of actions faster than conventional action-reward learning. This learning model is suitable to apply to nonstationary control domain where the rewards for actions vary over time. Based on the asynchronous action-reward learning, two situation reactive inventory control models (centralized and decentralized models) are proposed for a two-stage serial supply chain with nonstationary customer demand. A simulation based experiment was performed to evaluate the performance of the proposed two models. Chang Ouk Kim received his Ph.D. in industrial engineering from Purdue University in 1996 and his B.S. and M.S. degrees from Korea University, Republic of Korea in 1988 and 1990, respectively. From 1998--2001, he was an assistant professor in the Department of Industrial Systems Engineering at Myongji University, Republic of Korea. In 2002, he joined the Department of Information and Industrial Engineering at Yonsei University, Republic of Korea and is now an associate professor. He has published more than 30 articles at international journals. He is currently working on applications of artificial intelligence and adaptive control theory in supply chain management, RFID based logistics information system design, and advanced process control in semiconductor manufacturing. Ick-Hyun Kwon is a postdoctoral researcher in the Department of Civil and Environmental Engineering at University of Illinois at Urbana-Champaign. Previous to this position, Dr. Kwon was a research assistant professor in the Research Institute for Information and Communication Technology at Korea University, Seoul, Republic of Korea. He received his B.S., M.S., and Ph.D. degrees in Industrial Engineering from Korea University, in 1998, 2000, and 2006, respectively. His current research interests are supply chain management, inventory control, production planning and scheduling. Jun-Geol Baek is an assistant professor in the Department of Business Administration at Kwangwoon University, Seoul, Korea. He received his B.S., M.S., and Ph.D. degrees in Industrial Engineering from Korea University, Seoul, Korea, in 1993, 1995, and 2001 respectively. From March 2002 to February 2007, he was an assistant professor in the Department of Industrial Systems Engineering at Induk Institute of Technology, Seoul, Korea. His research interests include machine learning, data mining, intelligent machine diagnosis, and ubiquitous logistics information systems. An erratum to this article can be found at     

Exploiting edge semantics in citation graphs using efficient, vertical ARM

Graphs are increasingly becoming a vital source of information within which a great deal of semantics is embedded. As the size of available graphs increases, our ability to arrive at the embedded semantics grows into a much more complicated task. One form of important hidden semantics is that which is embedded in the edges of directed graphs. Citation graphs serve as a good example in this context. This paper attempts to understand temporal aspects in publication trends through citation graphs, by identifying patterns in the subject matters of scientific publications using an efficient, vertical association rule mining model. Such patterns can (a) indicate subject-matter evolutionary history, (b) highlight subject-matter future extensions, and (c) give insights on the potential effects of current research on future research. We highlight our major differences with previous work in the areas of graph mining, citation mining, and Web-structure mining, propose an efficient vertical data representation model, introduce a new subjective interestingness measure for evaluating patterns with a special focus on those patterns that signify strong associations between properties of cited papers and citing papers, and present an efficient algorithm for the purpose of discovering rules of interest followed by a detailed experimental analysis. Imad Rahal is a newly appointed assistant professor in the Department of Computer Science at the College of Saint Benedict ∣ Saint John's University, Collegeville, MN, and a Ph.D. candidate at North Dakota State University, Fargo, ND. In August 2003, he earned his master's degree in computer science from North Dakota State University. Prior to that, he graduated summa cum laude from the Lebanese American University, Beirut, Lebanon, in February 2001 with a bachelor's degree in computer science. Currently, he is completing the final requirements for his Ph.D. degree in computer science on an NSF ND-EPSCoR doctoral dissertation assistantship with August of 2005 as a projected completion date. He is very active in research, proposal writing, and publications; his research interests are largely in the broad areas of data mining, machine learning, databases, artificial intelligence, and bioinformatics. Dongmei Ren is working for the Database Technology Institute for z/OS, IBM Silicon Valley Lab, San Jose, CA, as a staff software engineer. She holds a Ph.D. degree from North Dakota State University, Fargo, ND, and master's and bachelor's degrees from TianJin University, TianJin, China. She has been a software engineer at DaTang Telecommunications, Beijing, China. Her areas of expertise are outlier analysis, data mining and knowledge discovery, database systems, machine learning, intelligent systems, wireless networks and bioinformatics. She has been awarded the Siemens Scholarship research enhancement for excellent performance in study and research. She is a member of ACM, IEEE. Weihua Wu is a network monitoring & managed services analyst at Hewlett-Packard Co. in Canada. He holds a master's degree from North Dakota State University and a bachelor's degree from Nanjing University, both in computer science. His research areas of interest include data mining, knowledge discovery, data warehousing, information technology, network security, and bioinformatics. He has participated in various projects supported by NSF, DARPA, NASA, USDA, and GSA grants. Anne Denton is an assistant professor in computer science at North Dakota State University. Her research interests are in data mining, knowledge discovery in scientific data, and bioinformatics. Specific interests include data mining of diverse data, in which objects are characterized by a variety of properties such as numerical and categorical attributes, graphs, sequences, time-dependent attributes, and others. She received her Ph.D. in physics from the University of Mainz, Germany, and her M.S. in computer science from North Dakota State University, Fargo, ND. Christopher Besemann received his M.Sc. in computer science from North Dakota State University in Fargo, ND, 2005. Currently, he works in data mining research topics including association mining and relational data mining with recent work in model integration as a research assistant. He is accepted under a fellowship program for Ph.D. study at North Dakota State University. William Perrizo is a professor of computer science at North Dakota State University. He holds a Ph.D. degree from the University of Minnesota, a master's degree from the University of Wisconsin and a bachelor's degree from St. John's University. He has been a research scientist at the IBM Advanced Business Systems Division and the U.S. Air Force Electronic Systems Division. His areas of expertise are data mining, knowledge discovery, database systems, distributed database systems, high speed computer and communications networks, precision agriculture and bioinformatics. He is a member of ISCA, ACM, IEEE, IAAA, and AAAS.     

ScaleSpaceViz: α-Scale spaces in practice

Kernels of the so-called α-scale space have the undesirable property of having no closed-form representation in the spatial domain, despite their simple closed-form expression in the Fourier domain. This obstructs spatial convolution or recursive implementation. For this reason an approximation of the 2D α-kernel in the spatial domain is presented using the well-known Gaussian kernel and the Poisson kernel. Experiments show good results, with maximum relative errors of less than 2.4%. The approximation has been successfully implemented in a program for visualizing α-scale spaces. Some examples of practical applications with scale space feature points using the proposed approximation are given. The text was submitted by the authors in English. Frans Kanters received his MSc degree in Electrical Engineering in 2002 from the Eindhoven University of Technology in the Netherlands. Currently he is working on his PhD at the Biomedical Imaging and Informatics group at the Eindhoven University of Technology. His PhD work is part of the “Deep Structure, Singularities, and Computer Vision (DSSCV)” project sponsored by the European Union. His research interests include scale space theory, image reconstruction, image processing algorithms, and hardware implementations thereof. Luc Florack received his MSc degree in theoretical physics in 1989 and his PhD degree cum laude in 1993 with a thesis on image structure, both from Utrecht University, the Netherlands. During the period from 1994 to 1995, he was an ERCIM/HCM research fellow at INRIA Sophia-Antipolis, France, and IN-ESC Aveiro, Portugal. In 1996 he was an assistant research professor at DIKU, Copenhagen, Denmark, on a grant from the Danish Research Council. From 1997 to June 2001, he was an assistant research professor at Utrecht University in the Department of Mathematics and Computer Science. Since June 1, 2001, he has been working as an assistant professor and, then, as an associate professor at Eindhoven University of Technology, Department of Biomedical Engineering. His interest includes all multiscale structural aspects of signals, images, and movies and their applications to imaging and vision. Remco Duits received his MSc degree (cum laude) in Mathematics in 2001 from the Eindhoven University of Technology, the Netherlands. Today he is a PhD student at the Department of Biomedical Engineering at the Eindhoven University of Technology on the subject of multiscale perceptual organization. His interest subtends functional analysis, group theory, partial differential equations, multiscale representations and their applications to biomedical imaging and vision, perceptual grouping. Currently, he is finishing his thesis “Perceptual Organization in Image Analysis (A Mathematical Approach Based on Scale, Orientation and Curvature).” During his PhD work, several of his submissions at conferences were chosen as selected or best papers—in particular, at the PRIA 2004 conference on pattern recognition and image analysis in St. Petersburg, where he received a best paper award (second place) for his work on invertible orientation scores. Bram Platel received his Masters Degree cum laude in biomedical engineering from the Eindhoven University of Technology in 2002. His research interests include image matching, scale space theory, catastrophe theory, and image-describing graph constructions. Currently he is working on his PhD in the Biomedical Imaging and Informatics group at the Eindhoven University of Technology. Bart M. ter Haar Romany is full professor in Biomedical Image Analysis at the Department of Biomedical Engineering at Eindhoven University of Technology. He has been in this position since 2001. He received a MSc in Applied Physics from Delft University of Technology in 1978, and a PhD on neuromuscular nonlinearities from Utrecht University in 1983. After being the principal physicist of the Utrecht University Hospital Radiology Department, in 1989 he joined the department of Medical Imaging at Utrecht University as an associate professor. His interests are mathematical aspects of visual perception, in particular linear and non-linear scale-space theory, computer vision applications, and all aspects of medical imaging. He is author of numerous papers and book chapters on these issues; he edited a book on non-linear diffusion theory and is author of an interactive tutorial book on scale-space theory in computer vision. He has initiated a number of international collaborations on these subjects. He is an active teacher in international courses, a senior member of IEEE, and IEEE Chapter Tutorial Speaker. He is chairman of the Dutch Biophysical Society.     

Designing systolic,distributed buffers with bounded response time

Several buffer designs are derived by applying a design methodology that is based on so-called abstract states. Abstract states are euivalence classes of communication histories. These abstract states are very useful in the verification of program transformations, since they facilitate the definition of a function mapping the states of the transformed automaton onto the states of the original one. Three kinds of bufferes are discussed: the stack, the first-in first-out queue, and the priority queue. The designs are systolic and offer bounded response time, which means that all permissible communications are accepted within a time bounded by a constant. The design of the stack offers maximum storage utilization as well. We show that the properties of bounded response time and maximum storage utilization cannot be combined in distributed systolic queues. Joep L.W. Kessels received an M.Sc. (Honors) degree in electrical engineering from the Eindhoven University of Technology, The Netherlands, in 1967. In 1969 he joined the Philips Research Laboratories in Eindhoven, where he has been involved in three major projects in the following research areas: applicative programming, distributed processing, and local area networks. Currently, he is engaged in the formal derivation of VLSI designs. His main research interests are design methodology and distributed processing. Martin Rem obtained an M.Sc. degree in mathematics at the University of Amsterdam in 1971 and a Ph.D. degree in computing science at the Eindhoven University of Technology in 1976. He is currently professor of mathematics and computing science at Eindhoven and part-time visiting professor at California Institute of Technology. Professor Rem is consultant for Philips Research and editor of Science of Computer Programming and Integration.     

Automatic diatom identification using contour analysis by morphological curvature scale spaces

A method for automatic identification of diatoms (single-celled algae with silica shells) based on extraction of features on the contour of the cells by multi-scale mathematical morphology is presented. After extracting the contour of the cell, it is smoothed adaptively, encoded using Freeman chain code, and converted into a curvature representation which is invariant under translation and scale change. A curvature scale space is built from these data, and the most important features are extracted from it by unsupervised cluster analysis. The resulting pattern vectors, which are also rotation-invariant, provide the input for automatic identification of diatoms by decision trees and k-nearest neighbor classifiers. The method is tested on two large sets of diatom images. The techniques used are applicable to other shapes besides diatoms. Andrei C. Jalba received his B.Sc. (1998) and M.Sc. (1999) in Applied Electronics and Information Engineering from “Politehnica” University of Bucharest, Romania. He recently obtained a Ph.D. degree at the Institute for Mathematics and Computing Science of the University of Groningen, where he now is a postdoctoral researcher. His research interests include computer vision, pattern recognition, image processing, and parallel computing. Michael Wilkinson obtained an M.Sc. in astronomy from the Kapteyn Laboratory, University of Groningen (RuG) in 1993, after which he worked on image analysis of intestinal bacteria at the Department of Medical Microbiology, RuG. This work formed the basis of his Ph.D. at the Institute of Mathematics and Computing Science (IWI), RuG, in 1995. He was appointed as researcher at the Centre for High Performance Computing (also RuG) working on simulating the intestinal microbial ecosystem on parallel computers. During that time he edited the book “Digital Image Analysis of Microbes” (John Wiley, UK, 1998) together with Frits Schut. After this he worked as a researcher at the IWI on image analysis of diatoms. He is currently assistant professor at the IWI. Jos B.T.M. Roerdink received his M.Sc. (1979) in theoretical physics from the University of Nijmegen, the Netherlands. Following his Ph.D. (1983) from the University of Utrecht and a 2-year position (1983--1985) as a Postdoctoral Fellow at the University of California, San Diego, both in the area of stochastic processes, he joined the Centre for Mathematics and Computer Science in Amsterdam. There he worked from 1986-1992 on image processing and tomographic reconstruction. He was appointed associate professor (1992) and full professor (2003), respectively, at the Institute for Mathematics and Computing Science of the University of Groningen, where he currently holds a chair in Scientific Visualization and Computer Graphics. His current research interests include biomedical visualization, neuroimaging and bioinformatics. Micha Bayer graduated from St. Andrews University, Scotland, with an M.Sc. in Marine Biology in 1994. He obtained his Ph.D. in Marine Biology from there in 1998, and then followed this up with two postdoctoral positions at the Royal Botanic Garden Edinburgh, Scotland, first on the ADIAC and then on the DIADIST project. In both of these projects he was responsible for establishing the collections of diatom training data to be used for the pattern recognition systems. From 2002–2003 he was enrolled for an M.Sc. in information technology at the University of Glasgow, Scotland, and is now working as a grid developer at the National e-Science Centre at Glasgow University. Stephen Juggins is a senior lecturer at the School of Geography, Politics and Sociology, University of Newcastle. His research focuses on the use of diatoms for monitoring environmental change and on the analysis of ecological and palaeoecological data. He has worked in Europe, North America and Central Asia on problems of river water quality, historical lake acidification, coastal eutrophication and Quaternary climate change.     

An agent architecture for strategy-centric adaptive QoS control in flexible videoconference system

In this paper, we propose an agent architecture to improve flexibility of a videoconference system with strategy-centric adaptive QoS (Quality of Service) control mechanism. The proposed architecture realizes more flexibility by changing their QoS control strategies dynamically. To switch the strategies, system considers the properties of problems occurred on QoS and status of problem solving process. This architecture is introduced as a part of knowledge base of agent that deals with cooperation between software module of videoconference systems. We have implemented the mechanism, and our prototype system shows its capability of flexible problem solving against the QoS degradation, along with other possible problems within the given time limitation. Thus we confirmed that the proposed architecture can improve its flexibility of a videoconference system compared to traditional systems. Takuo Suganuma, Dr.Eng.: He is a research associate of Research Institute of Electrical Communication of Tohoku University. He received a Dr.Eng. degree from Chiba Institute of Technology in 1997. His research interests include agent-based computing and design methodology for distributed systems. He is a member of IPSJ, IEICE and IEEE. SungDoke Lee: He is a Ph.D. Student in the Graduate School of Information Sciences in Tohoku University. He received his MEng degree at Chonbuk National University, Korea in 1991. His research interests include Flexible Network and Knowledge of Agent. Tetsuo Kinoshita, Dr.Eng.: He is an associate professor of Research Institute of Electrical Communication of Tohoku University. He received a Dr.Eng. degree in information engineering from Tohoku University, Japan. His research interests include knowledge engineering, cooperative distributed processing and agent-based computing. He received the the IPSJ Best Paper Award in 1997, etc. He is a member of IPSJ, IEICE, JSAI, AAAI, ACM and IEEE. Norio Shiratori, Dr.Eng.: After receiving his Dr.Eng degree at Tohoku University, he joined the Research Institute of Electrical Communication of Tohoku University in 1977, and is now a professor at the same University. He has been engaged in research on distributed processing system, and flexible intelligent network. He received the 25th Anniversary of IPSJ Memorial Prize-Winning Paper Award in 1985, the 6th Telecommunications Advancement Foundation Incorporation Award in 1991, the Best Paper Award of ICOIN-9 in 1994, the IPSJ Best Paper Award in 1997, etc. He has been named a Fellow of the IEEE for his contributions to the field of computer communication networks.     

On the suitability of Biological structure determination by electron microscopy to Grid Computing

The present contribution describes a potential application of Grid Computing in Bioinformatics. High resolution structure determination of biological specimens is critical in BioSciences to understanding the biological function. The problem is computational intensive. Distributed and Grid Computing are thus becoming essential. This contribution analyzes the use of Grid Computing and its potential benefits in the field of electron microscope tomography of biological specimens. Jose-Jesus Fernandez, Ph.D.: He received his M.Sc. and Ph.D. degrees in Computer Science from the University of Granada, Spain, in 1992 and 1997, respectively. He was a Ph.D. student at the Bio-Computing unit of the National Center for BioTechnology (CNB) from the Spanish National Council of Scientific Research (CSIC), Madrid, Spain. He became an Assistant Professor in 1997 and, subsequently, Associate Professor in 2000 in Computer Architecture at the University of Almeria, Spain. He is a member of the supercomputing-algorithms research group. His research interests include high performance computing (HPC), image processing and tomography. Jose-Roman Bilbao-Castro: He received his M.Sc. degree in Computer Science from the University of Almeria in 2001. He is currently a Ph.D. student at the BioComputing unit of the CNB (CSIC) through a Ph.D. CSIC-grant in conjuction with Dept. Computer Architecture at the University of Malaga (Spain). His current research interestsinclude tomography, HPC and distributed and grid computing. Roberto Marabini, Ph.D.: He received the M.Sc. (1989) and Ph.D. (1995) degrees in Physics from the University Autonoma de Madrid (UAM) and University of Santiago de Compostela, respectively. He was a Ph.D. student at the BioComputing Unit at the CNB (CSIC). He worked at the University of Pennsylvania and the City University of New York from 1998 to 2002. At present he is an Associate Professor at the UAM. His current research interests include inverse problems, image processing and HPC. Jose-Maria Carazo, Ph.D.: He received the M.Sc. degree from the Granada University, Spain, in 1981, and got his Ph.D. in Molecular Biology at the UAM in 1984. He left for Albany, NY, in 1986, coming back to Madrid in 1989 to set up the BioComputing Unit of the CNB (CSIC). He was involved in the Spanish Ministry of Science and Technology as Deputy General Director for Research Planning. Currently, he keeps engaged in his activities at the CNB, the Scientific Park of Madrid and Integromics S.L. Immaculada Garcia, Ph.D.: She received her B.Sc. (1977) and Ph.D. (1986) degrees in Physics from the Complutense University of Madrid and University of Santiago de Compostela, respectively. From 1977 to 1987 she was an Assistant professor at the University of Granada, from 1987 to 1996 Associate professor at the University of Almeria and since 1997 she is a Full Professor and head of Dept. Computer Architecture. She is head of the supercomputing-algorithms research group. Her research interest lies in HPC for irregular problems related to image processing, global optimization and matrix computation.