ΤΜΗΜΑ ΠΛΗΡΟΦΟΡΙΚΗΣ ΚΑΙ ΤΗΛΕΠΙΚΟΙΝΩΝΙΩΝ
ΣΕΜΙΝΑΡΙΟ ΤΗΛΕΠΙΚΟΙΝΩΝΙΩΝ ΕΠΕΞΕΡΓΑΣΙΑΣ ΣΗΜΑΤΟΣ ΚΑΙ ΔΙΚΤΥΩΝ
Στο σεμινάριο Τηλεπικοινωνιών, Επεξεργασίας Σήματος και Δικτύων του Τμήματος
Πληροφορικής και Τηλεπικοινωνιών του Πανεπιστημίου Αθηνών παρουσιάζονται
ερευνητικές και άλλες συναφείς δραστηριότητες στον γενικότερο γνωστικό χώρο των
τηλεπικοινωνιών, της επεξεργασίας σήματος και των δικτύων.
Οι ομιλίες παρουσιάζονται στην
Αίθουσα Τηλεδιασκέψεων Κέντρου Διαχείρισης Δικτύων. Πιθανές εξαιρέσεις θα
ανακοινώνονται ανά περίπτωση.
Η πλέον πρόσφατη παρουσίαση δεικνύεται με πράσινο χρώμα στο φόντο.
Η φυσική πρόσβαση στο Τμήμα
Πληροφορικής & Tηλεπικοινωνιών,
μπορεί να γίνει με μετρό-λεωφορείο (Metro-Buses).
ΠΡΟΓΡΑΜΜΑ ΟΜΙΛΙΩΝ 2008-2009
|
ΟΝΟΜΑ |
ΗΜΕΡΟΜΗΝΙΑ |
ΤΙΤΛΟΣ ΟΜΙΛΙΑΣ |
|
Dr. Takis Mathiopoulos,
Διευθυντής Ερευνών, Ινστιτούτο Διαστημικών Εφαρμογών και Τηλεπισκοπισηςn, Εθνικό Αστεροσκοπείο Αθηνών, |
Τετάρτη 24 Ιούνιου 2009 (14:00) |
|
|
Prof. Nikos D. Sidiropoulos,
Telecommunications Division, Department of Electronic & Computer Engineering, Technical University of Crete, |
Δευτέρα 22 Ιούνιου 2009 (14:00) |
"Joint transmit beamforming and admission control under QoS constraints" |
|
Prof. Λέανδρος Τασιούλας,
University of Thessaly, Volos, |
Τετάρτη 17 Ιούνιου 2009 (11:00) |
"A cross-layer approach in architecting wireless communication systems" |
|
Prof. Andreas Polydoros,
Department of Physics, University of Athens, |
Τετάρτη 10 Ιούνιου 2009 (14:00) |
"Introduction to flexible-radio concepts with some examples" |
|
Prof. Francky
Catthoor, KUL & IMEC, |
Τετάρτη 27 Μαίου 2009 (15:00) |
"Handling yield and life-time guarantees in a dynamic deep-submicron system context" |
|
Associate Prof.
George-Othon Glentis, Department of Science and Technology of
Telecommunications, |
Τετάρτη 18 Μαίου 2009 (15:00) |
|
|
Assist. Prof. Dimitrios Soudris,
MicroLab, ECE NTUA, Greece |
Τρίτη 12 Μαίου 2009 (12:00) |
" 3D Integration: Architectures and CAD tools for Reconfigurable Platforms " |
|
Dr. Nikolaos Laoutaris, Telefonica Research |
Πέμπτη 26 Μαρτίου 2009 (10:00) ΑΙΘΟΥΣΑ ΣΥΝΕΔΡΙΑΣΕΩΝ |
|
|
Georgios Smaragdakis, Deutsche Telekom Labs/TU
Berlin |
Πέμπτη 26 Μαρτίου 2009 (11:45) ΑΙΘΟΥΣΑ ΣΥΝΕΔΡΙΑΣΕΩΝ |
|
|
Prof. Sergios
Theodoridis, Dept. of Informatics and Telecommunications |
Πέμπτη 19 Φεβρουαρίου 2009 (13:00) |
|
|
Prof. Nick
Bambos, |
Παρασκεύη 13 Φεβρουαρίου 2009 (13:30) |
"Power and Throughput Issues in Next-Generation Packet Switches" |
|
Dr. Artemis Hatzigeorgiou, Ερευνητικό Κέντρο Βιοϊατρικών Επιστημών
"Αλέξανδρος Φλέμινγκ" |
Πέμπτη 5 Φεβρουαρίου 2009 (13:00) |
"Μηχανική μάθηση στην βιοπληροφορική :
Κατανοώντας την λειτουργία των γονιδίων" |
|
Dr. Prof. Martin
Carle, |
Τρίτη 9 Δεκεμβρίου 2008 (13:00) |
|
|
Prof. Jean
Dominique Decotignie, Ηead of the real-time software and networking group at
CSEM, |
Τετάρτη 17 Σεπτεμβρίου 2008 (13:00) ΑΙΘΟΥΣΑ ΣΥΝΕΔΡΙΑΣΕΩΝ |
"Real-Time and wireless sensor networks : why do we need another view at it?" |
|
Dr. Enrico Buracchini, Telecom Italia
Laboratories (TILab) |
Τετάρτη 10 Σεπτεμβρίου 2008 (18:00) |
"Towards 4G or more (an excursion from GSM to Cognitive Radios)" |
|
Prof. Oriol Sallent, Universitat Politecnica de Catalunya |
Δευτέρα 8 Σεπτεμβρίου 2008 (18:00) |
ΠΕΡΙΛΗΨΕΙΣ ΟΜΙΛΙΩΝ
24 Ιούνιου 2009 (Τετάρτη 14:00)
Ομιλητής: Dr. Takis Mathiopoulos
"Digital Communications over Fading Channels"
In this lecture we will be reviewing the most important fading channel models and discuss associated receiver structures. Emphasis will be given to the maximum likelihood sequence estimation receiver which has lead to the so-called multiple differential detection (MDD) receiver structure for fading channels. Then we will be presenting the most important diversity receiver techniques and their application to a "new" class of fading channels, namely the Weibull fading channels. Finally, we will be discussing some open research problems promising for future investigation.
Short CV: P. Takis Mathiopoulos was born in Athens, Greece, in 1956.
He received the Diploma in Electrical Engineering from the University of Patras,
Greece, in 1979, the M.Eng. degree in microwave engineering from Carleton University,
in 1983, and the Ph.D. degree in digital communications from the University of Ottawa,
Canada, in 1989. From 1982 - 1986, he was with Raytheon Canada Ltd., working in the
areas of air navigational and satellite communications. In 1989, he joined the Department
of Electrical and Computer Engineering (ECE), University of British Columbia (UBC),
Canada, where he was a faculty member for 13 years, last holding the rank of Professor.
From 1999 - 2004, he was the Director of the Institute for Space Applications and Remote
Sensing (ISARS), National Observatory of Athens (NOA), where he established the Wireless
Communications Research Group, and has led the Institute to a significant expansion. He now
holds at ISARS the position of Director of Research. Since 2003 he also teaches part-time
at the Department of Informatics and Telecommunications, University of Athens. In 2008 he
was appointed as a Guest Professor at the Southwest Jiaotong University, Chengdu, China.
For the last 20+ years, he has been conducting research on the physical layer of digital
communication systems for terrestrial and satellite applications. Specific research activities
include digital communications over fading and interference environments, channel characterization
and measurements, modulation and coding techniques, SIMO/MIMO, UWB, OFDM, and software/cognitive
radios. He has served on the editorial board of many journals, including the IEEE Transactions
on Communications (1993-2003). He was an ASI Fellow, a Killam Research Fellow and a co-recipient
of the best paper award from the 2008 International Conference on Communication, Control, and
Signal Processing (ICCSP).
22 Ιούνιου 2009 (Δευτέρα 14:00)
Ομιλητής: Prof. Nikos D. Sidiropoulos
"Joint transmit beamforming and admission control under QoS constraints"
Transmit beamforming under QoS constraints is of interest in a number of emerging technologies, including UMTS-LTE and 802.16e. The downlink version in which different data streams are transmitted to the individual users is a convex problem, but potential infeasibility is a key issue that necessitates appropriate scheduling and admission control strategies. In parallel, there is growing interest in appropriate beamforming for (PHY-layer) multicasting, where the goal is to transmit common information to *groups* of users - e.g., in the context of LTE / E-MBMS. In this talk we will highlight recent developments in transmit beamforming and joint beamforming and admission control. We show that optimal designs are NP-hard; but we also show that it is possible to develop efficient and effective solutions via convex approximation. The idea is to approximate a non-convex NP-hard problem by a suitable convex problem which is close to the original one; the solution of the convex problem then guides the search for a good approximate solution of the original problem. Analytical approximation guarantees can be provided in certain cases.
Short CV: Nikos Sidiropoulos received the Diploma in EE from the
Aristotelian University of Thessaloniki, Greece, and M.S. and
Ph.D. degrees in EE from the University of Maryland, in 1988, 1990 and
1992, respectively. He has been a Postdoctoral Fellow and later Research
Scientist at the Institute for Systems Research, University of Maryland
(1994-1997), Assistant Professor in the Dept. of EE at the University of
Virginia (1997-1999), and Associate Professor in the Dept. of ECE
at the University of Minnesota - Minneapolis (2000-2002). Since 2002, he
is Professor in the Dept. of ECE, Technical University of Crete, Chania -
Crete, Greece, and Adjunct Professor at the University of Minnesota. His
current research interests are primarily in signal processing for
communications, convex optimization, cross-layer resource allocation for
wireless networks, and multi-linear algebra. He has served as chair (2007
- 2008) of the Signal Processing for Communications Technical Committee
(SPCOM-TC) of the IEEE SP Society. He received the U.S. NSF/CAREER award
in June 1998, and the IEEE SPS Best Paper Award twice (in 2001 and 2007).
Prof. Sidiropoulos is a Distinguished Lecturer of the IEEE SPS for
2008-2009, and a Fellow of IEEE for contributions to signal processing for
communications.
Email: nikos@telecom.tuc.gr
Web Page: http://www.telecom.tuc.gr/~nikos/
17 Ιούνιου 2009 (Τετάρτη 11:00)
Ομιλητής: Prof. Λέανδρος Τασιούλας
"A cross-layer approach in architecting wireless communication systems"
Wireless technology advances over the last few years lead to sophisticated physical layer designs that may interact with the access and network layer in multiple modes. Link quality related information is passed from the physical layer, to be used in access and network layer actions. At the same time several considerations belonging naturally to the physical layer, like channel coding rate, signal constellation selection, power level adjustments, frequency selection and beam steering in multiple antenna systems are to the disposal of the access layer, that may control them in various time scales. That interaction is particularly useful for full exploitation of the volatile error-prone mobile channel and the establishment of reliable broadband wireless links in the interference limited radio medium. In this talk we will present novel approaches for architecting and operating wireless networks that integrate seamlessly the layers from physical to network. Performance benefits and implementation challenges both in terms of computational complexity as well as state information availability will be presented. Furthermore we will present an experimental effort under way addressing these issues, in the newly developed wireless network testbed at the University of Thessaly.
Short CV: Leandros Tassiulas (S'89, M'91, SM/05 F/07) obtained the Diploma in
Electrical Engineering from the Aristotelian University of Thessaloniki, Thessaloniki, Greece in 1987, and the M.S. and Ph.D. degrees in Electrical Engineering from the University of Maryland, College Park in 1989 and 1991 respectively.
He is Professor in the Dept. of Computer and Telecommunications Engineering,
University of Thessaly since 2002. He has held positions as Assistant Professor at Polytechnic University New
York (1991-95), Assistant and Associate Professor University of Maryland College Park
(1995-2001) and Professor University of Ioannina Greece (1999-2001).
His research interests are in the field of multi-user communication systems
with emphasis on cross-layer architectures, algorithms and implementations
of wireless systems. Dr. Tassiulas is a Fellow of IEEE. He received a National Science Foundation
(NSF) Research Initiation Award in 1992, an NSF CAREER Award in 1995,
an Office of Naval Research, Young Investigator Award in 1997 and a
Bodossaki Foundation award in 1999. He also received the INFOCOM 1994 best paper award and the INFOCOM 2007
achievement award.
Web Page: http://www.inf.uth.gr/~leandros
10 Ιούνιου 2009 (Τετάρτη 14:00)
Ομιλητής: Prof. Andreas Polydoros
"Introduction to flexible-radio concepts with some examples"
Flexibility in radio terminals and networks does not need much of a motivation nowadays:
it is an important new field, populated by multiple players. It is a complex and inter-disciplinary
scientific domain, thus requiring a multi-lateral meeting of viewpoints, scientific resources and backgrounds.
After a brief introduction on motivation and taxonomy, we will provide our (debatable) viewpoint on the
qualification of flexibility in this radio-system context and the quantification of its efficient instantiations.
Specific examples will be given to clarify the concepts, drawn from the algorithmic/signal-processing domain of
the baseband PHY layer. Emphasis will be given to new methodologies for link adaptivity.
Short CV: Andreas Polydoros was born in Athens, Greece, in 1954. He was educated at the National
Technical University of Athens (Diploma in EE, 1977), State University of New York at Buffalo (MSEE, 1979)
and the University of Southern California -- USC (Ph.D., EE, 1982). He was a faculty member at USC in the
Electrical Engineering Department/Systems and the Communication Sciences Institute (CSI) in 1982-1997, a
Professor since 1992. He co-directed CSI in 1991-93. Since 1997 he has been Professor in the Department of
Physics, University of Athens. He directed the Electronics Laboratory there until 2007.
His general area of scientific interest is stochastic communication theory with applications to spread-spectrum,
digital radio terminals and networks, signal detection/classification, and data-demodulation/parameter-estimation
in uncertain environments. He was elected Fellow of the IEEE in 1995.
27 Μαίου 2009 (Τετάρτη 15:00)
Ομιλητής: Prof. Francky Catthoor
"Handling yield and life-time guarantees in a dynamic deep-submicron
system context"
The deep-submicron evolution leads to ever-growing reduction of the design margins and less reliable devices due to the shrinking dimensions. In order to mitigate these effects, and to still be able to guarantee acceptable yield and life-times for the future chips, it is well-accepted now that "reliable system design with unreliable components" is becoming a must. In this presentation, some of the underlying mechanisms will be illustrated first as motivational setting. But the main focus will be on how to design on-line proactive controllers to steer dynamic systems while still providing hard guarantees on constraints (like timing, minimal yield and life times) and minimizing the system cost (like area overhead in the mitigation infrastructure and the required energy consumption).
Short CV: Francky Catthoor received the engineering degree and a
Ph.D. in electrical engineering from the Katholieke Universiteit Leuven,
18 Μαίου 2009 (Δευτέρα 15:00)
Ομιλητής: Associate Prof. George-Othon Glentis
"Efficient algorithms for amplitude spectrum estimation"
Amplitude spectrum estimation is of great interest in a wide range of applications, including speech processing and analysis, time series analysis, geophysics, biomedical engineering, synthetic aperture radar imaging, etc. The Amplitude and Phase Estimator (APES), the Amplitude Spectrum Capon (ASC) and the Power Spectrum Capon (PSC), are three popular high resolution spectral estimators. However, direct implementation of these methods is prohibited due to the huge amount of computational power required. The purpose of this lecture is to present new efficient algorithms for the computation of the amplitude spectrum. To achieve this goal, suitable Gohberg-Semencul (G-S) type factorization of the pertinent data-matrices is derived. Based on this particular representation, a fast computational scheme is developed for the computation of the PSC, the ASC and the APES spectra.
Short CV: George-Othon Glentis was born in
12 Μαίου 2009 (Τρίτη 12:00)
Ομιλητής: Assist. Prof. Dimitrios Soudris
"3D Integration: Architectures and CAD tools for Reconfigurable
Platforms"
Three-dimensional (3-D) integration has emerged as a revolutionary technology that can satisfy these requirements. The shift from horizontal scaling to volumetric stacking of circuits has the potential to mitigate the many limitations of modern integrated circuits. 3-D architectures contain multiple physical layers and offer considerable improvement in circuit performance, such as lower power/energy consumption, less total wire-length, higher integration density, and greater speed comparing with two-dimensional (2-D) circuits. The interconnect fabric in modern Field Programmable Gate Arrays (FPGAs) comprises a considerable portion of the overall delay, power consumption, and silicon area. We present a design methodology to evaluate different 3-D fabrication technologies and investigate heterogeneous interconnection schemes for 3-D FPGAs. A software-supported framework is developed for designing 3D reconfigurable the exploration methodology.
Short CV: Dr. Dimitrios Soudris received his Diploma in Electrical Engineering
from the
26 Μαρτίου 2009 (Πέμπτη 10:00)
Ομιλητής: Dr. Nikolaos Laoutaris
"Delay Tolerant Bulk Data Transfers on the Internet or how to book some
terabytes on "red-eye" bandwidth"
Many emerging scientific and industrial applications require transferring
multiple terabytes of data on a daily basis. Examples include pushing
scientific datasets from particle accelerators/colliders to laboratories around
the world, synchronizing data centers in different continents, and replicating
collections of high definition videos from Olympic games taking place on a
different time-zone. A convenient property of all above applications is their
ability to tolerate delivery delays from a few hours to a few days. Such
Delay-Tolerant Bulk (DTB) transfers are currently being serviced through the
postal system using hard drives and DVDs, or through expensive dedicated networks.
In this work we develop store-and-forward (SnF) scheduling policies for
achieving low-cost transfer of DTB data over existing public networks. We use
traffic data from 200+ links of a large transit ISP to show that the naive
approach of using end-to-end (E2E) connection oriented transfers can be
prohibitively expensive under common percentile charging schemes. The problem
is that despite the existence of strong diurnal load patterns that leave lots
of free bandwidth during off-peak hours, E2E transfers are unable to provide
low end-to-end cost because very often the load ``valley'' of a sender does not
coincide in time with the load valley of an intended receiver. By utilizing
network storage at main PoPs, our SnF policies time-shift DTB transfers in
order to bridge the gap between non coinciding valleys, and thus reduce, even
zero, the incurred transit costs. Similarly, under a flat-rate pricing scheme,
complementarities in the available bandwidth at the two end points of a DTB
flow that crosses multiple time zones may limit the end-to-end available rate
to a very small value. In this case SnF scheduling can be used to increase the
perceived effective transmission rate.
This talk is based on joint work with: Hitesh Ballani (Cornell), Pablo
Rodriguez (Telefonica Research), Georgios Smaragdakis (Deutsche Telekom Labs),
and
Short CV:Nikolaos Laoutaris is a research scientist at Telefonica
Research,
Email: nikos@tid.es
Web Page: http://research.tid.es/nikos/
26 Μαρτίου 2009 (Πέμπτη 11:45)
Ομιλητής: Dr. Georgios Smaragdakis
"ORACLE: an ISP-P2P Collaboration System"
Peer-to-Peer (P2P) systems account for a significant portion of Internet traffic and an increasing number of user applications. P2P systems build overlays at the application layer, largely agnostic to Internet routing, Internet Service Providers (ISP) routing policies and topologies. This leads to measurement traffic overhead and routing inefficiencies for P2P users. Moreover, ISPs loose the control of their traffic that may lead to high congestion and increase of their operational expenses. The current situation is disadvantageous for both the ISPs and P2P users. Previous solutions to the problem are either against network neutrality (ISP bandwidth throttling), suboptimal and not scalable (end-host proximity inference), or unrealistic as they require that the ISP will reveal its topology to P2P system developers. We argue that the collaboration between ISPs and P2P systems, in a way that none of two parts has to reveal any information on the way it operates, is the key to the solution. We propose and evaluate the feasibility of a solution where an ISP offers a recommendation service, the ORACLE, to the P2P users. A P2P user supplies the ORACLE with a list of candidate peers, the ORACLE ranks them based on certain criteria, and then sends the ranked list back to the P2P user. Our results show that the performance of P2P users that follow Oracle's recommendation is significantly better than those that do not use the service. Our results also show that ISP can use Oracle to better better manage the immense P2P traffic inside its network or to direct it along a desired path.
Short CV:Georgios Smaragdakis is a Senior Research Scientist at
Deutsche Telekom Laboratories and the Technical University of Berlin. He earned
his Ph.D. in computer science from
Web Page: http://www.smaragdakis.net
19 Φεβρουαρίου 2009 (Πέμπτη 13:00)
Ομιλητής: Prof. Sergios Theodoridis
"Adaptive Learning in a World of Projections"
The task of parameter/function estimation has been at the center of scientific attention for a long time and it comes under different names such as filtering, prediction, beamforming, curve fitting, classification, regression. In this talk, the estimation task is treated in the context of set theoretic estimation arguments. Instead of a single optimal point we are searching for a set of solutions that are in agreement with the available information, which is provided to us in the form of a set of training points and a set of constraints. The goal of this talk is to present a general tool for parameter/function estimation, under a set of convex constraints, both for classification as well as regression tasks, in a time adaptive setting in (infinite dimensional) Reproducing Kernel Hilbert spaces (RKHS). Each algorithm consists of a sequence of projections, of linear complexity with respect to the number of unknown parameters. Our theory proves that the algorithm converges to the intersection of all (with a possible exception of a finite number of) the convex sets, where the required solution lies. The performance of the methodology is demonstrated in the context of robust beam forming in communication systems. The work has been carried out in cooperation with Kostas Slavakis and Isao Yamada.
Short CV: Sergios Theodoridis is currently Professor of Signal Processing
and Communications in the Department of Informatics and Telecommunications of
the
13 Φεβρουαρίου 2009 (Παρασκευή 13:30)
Ομιλητής: Prof. Nick Bambos
"Power and Throughput Issues in Next-Generation Packet Switches"
High-speed packet switches achieve increasingly higher throughputs and better jitter management at the expense, however, of substantial increase in utilized power. The latter has become an acute problem, as higher power results in unacceptable thermal stress of switching chips/systems and requires extensive cooling apparatus. Low power circuit design is one way to partially address the problem. Instead, in this talk we focus on operational and algorithmic methods for power managing switches. We present some recent results for power-aware packet scheduling in packet switches. We focus on the power vs. latency tradeoff and discuss how to systematically manage power/speed modes against acceptable packet delays and traffic bursts. The power management algorithms are also aligned with the need to achieve maximal throughput when the traffic load becomes excessive.
Short CV: Nick Bambos is Professor at
5 Φεβρουαρίου
2009 (Πέμπτη 13:00)
Ομιλητής: Dr. Artemis Hatzigeorgiou
"Μηχανική μάθηση στην βιοπληροφορική : Κατανοώντας την λειτουργία των
γονιδίων"
Η ομιλία θα περιγράψει βασικά
προβλήματα και μεθόδους της βιοπληροφορικής. Ειδικότερα θα αναφερθεί σε
πρωτότυπους αλγόριθμους βασισμένους στην τεχνητή νοημοσύνη (επαναλαμβανόμενα
νευρωνικά δίκτυα) που οδηγούν στην πρόβλεψη και κατανόηση του λειτουργικού
ρόλου μικροσυστοιχιών RNA σε
σχέση με την έκφραση των γονιδίων στο DNA του ανθρώπου.
Short CV: Η κα Χατζηγεωργίου έχει κάνει βασικές σπουδές
στην πληροφορική και μεταπτυχιακές σπουδές στην μοριακή βιολογία. Από το
2001-2007 κατείχε θέση επίκουρου καθηγητή στο Πανεπιστήμιο της Πεννσυλβάνιας
στο Τμήμα Γενετικής της Ιατρικής Σχολής και Πληροφορική και από το 2007 θέση
κατέχει θέση υπεύθυνου ερευνητή στο Ε.ΚΕ.Β.Ε. «Αλέξανδρος Φλέμινγκ». Έχει λάβει
το βραβείο «Young Investigation Career Award» από το Εθνικό Υδρημα Ερευνών ( NSF) των ΗΠΑ και η ερευνητική της εργασία
έχει δημοσιεύσει σε περιοδικά ευρύτατης αναγνωσιμότητας οπως Nature, Science, PNAS κ.α. .
9 Δεκεμβρίου 2008 (Τετάρτη 13:00)
Ομιλητής: Prof. Martin Carle
"ENIAC NOMOI -- A media-archeological perspective on melody and
computation. An applied journey from ancient Acoustic Theory to Sonification by
means of signal processing and simulation"
Today's idea of a Turing galaxy into which the Greek musical kosmos seems to have emptied itself is dependent on the concept of symbolic process and communication theory. However, symbolic processes are still carried out by arithmetical and real-world physical operations that, within current media technology and especially in the domain of physical modelling and musical communication, call forth quasi-physical time constraints in order to succeed. Thus in the realm of real-time simulation, both mathematical necessity and the temporality of symbolic operations are to be considered and become entangled with each other. This in turn produces at least two main consequences to be followed during the talk: The first is that the basic epistemological motivation for the term 'kosmos' unveils itself again, and the second is that the adjunctive Aristotelian conception of 'mimesis' reveals the need for a deep reconsideration in the context of media and of its musico-dramatic origins. Besides the presentation of applied media-philosophical projects following those lines, it should become obvious how the sonification of theoretical models are unforetold descendants of the Greek enharmonic sonosphere and its underestimated theory of melodic process. The talk tries to exemplify this train of thought by means of archeo-musicological methods, attempting a critique of 'the symbolic' and the idea of a Turing galaxy. Unearthing a concrete machine that has become known as the 'first electronic computer' – the ENIAC - signal processing (MatLab), simulation technology (Simulink) and real-time audio synthesis (SuperCollider) are introduced and chained into a streamlined methodology for rapid prototyping and acoustic engineering. Altogether we are lead to an unforeseen disclosure spoken forth by the US War Department’s press release, issued Feb. 15. 1946: “it is worthy of note that the ENIAC established the fact that the basic principles of electronic computing are sound.” Evidently the War Department's use of the word 'sound' was not meant in the way that I shall demonstrate is ontologically true.
Short CV: Martin Carl is a media scientist, musicologist and philosopher. He lectured as assistant professor in media theory at Humboldt-University Berlin. His research focuses on the epistemic ties between music technology, the temporality of simulation and media theory. Using programming and modeling as means of research in humanities, he developed environments of sonification and introduced acoustic archeology as a method of critical discourse. Recent publications include: Signalmusik MKII (Kadmos, 2006), Parasemantics and Enharmony. Coding and Decoding the Ancient Greek Sonosphere. (SIM PK, 2008), Cat-Notation. Incl. a text on: Simulation - Emulation - Preemption. (Merve 2009, forthcoming).
17
Σεπτεμβρίου 2008 (Τετάρτη 13:00) ΠΡΟΣΟΧΗ! η διάλεξη θα λάβει μέρος στην ΑΙΘΟΥΣΑ
ΣΥΝΕΔΡΙΑΣΕΩΝ του τμήματος.
Ομιλητής: Prof. Jean Dominique Decotignie
"Real-Time and wireless sensor networks : why do we need another view
at it?"
Networking at the sensory level is now very common. Fieldbusses have been around for more than 2 decades They can be found in many types of application such as factory automation, process plants, car automation or building automation. Since the first solutions were designed in the early 80s, a number of proposals have flourished and the field is well established both in terms of research and industrial use. Most solutions use wired transmission (twisted pairs, coaxial cables, optical fibers) and provide real-time guarantees at different degrees. Establishing these guarantees has been the subject of a number of papers in previous issues of this workshop. Using wireless transmission at the sensory level is very attracting. It has been employed for years to link mobile robots or automated guided vehicles to control and supervision computers. At the fieldbus level, a number of solutions have been proposed. The Esprit Project OLCHFA designed in 1992 a full wireless network based on the FIP protocol. LON offers some wireless transceivers that can be used to built a mixed wired / wireless network. The same applies to the first version of the IEC fieldbus. Wireless extensions to Profibus were studied within the R-Fieldbus IST project. Wireless HART is now an established solution in the process control domain. Wireless sensor networks have emerged at the very beginning of this century as a separate subject leading to a huge quantity of publications with little concern about time. More recently, temporal issues are starting to interest researchers and there are a few proposals claiming real-time support such as IEEE 802.15.4. It is tempting to reuse in the WSN context the solutions that were developed to construct real-time fieldbusses and the techniques that we employed to analyze the temporal properties. There are however fundamental differences between the propagation properties on cable and in the wireless case. Two of them are the probability that a message is not received correctly and the path losses. Wireless transmission suffers from much higher BER and higher attenuations. While the latter is taken into account in most solutions, the former is mostly ignored when dealing with real-time properties. For instance, papers keep stating that pure TDMA or IEEE 802.15.4 offer real-time guarantees because they avoid collisions. This is true in absence of transmission error, an assumption that does not hold in the wireless domain. It is easy to show that hard real-time bounds are impossible to guarantee in wireless communications. There is thus a need to find another way to define the real-time properties of wireless sensor networks. The talk will explore some of these ways and also explain why pure TDMA is unlikely to be a good solution to support real-time guarantees.
Short CV: Jean-Dominique Decotignie is head of the real-time software and networking group at CSEM. He is also adjunct professor at the Ecole Polytechnique Fιdιrale de Lausanne (EPFL), CH. From 1977 to 1982, he has worked at EPFL and the University of Tokyo in the area of optical communications. In 1983, he joined the Industrial Computer Engineering Lab. at EPFL where he became Assistant Professor in 1992. From 1989 to 1992, he has been the head of an interdisciplinary project of Computer Integrated Manufacturing at EPFL. Since January 1997, he is with CSEM. His current research interests include real-time networks and self-organizing wireless sensor networks as well as software engineering and middleware for real-time systems. Dr. Decotignie received his MS in 1977 and PhD in 1982 both in electrical engineering from the EPFL. He has published more than 100 papers in international journals and conferences. He is an IEEE fellow.
10 Σεπτεμβρίου 2008 (Τετάρτη 18:00)
Ομιλητής: Dr. Enrico Buracchini
"Towards 4G or more (an excursion from GSM to Cognitive Radios)"
Short CV: Mr. Enrico Buracchini received, with full marks, the degree in Electronics Engineering from the University of Bologna in October 1994. In December 1994, he was employed in the Mobile Services Division of CSELT (R&D labs of Telecom Italia Group), now TILab, as a Research Engineer. His activity concerns the study of multiple access methods (TDMA, CDMA, OFDMA) for mobile communications systems. He was part of Italian Delegation to ITU R TG8/1 group dedicated to IMT 2000 standardisation and he is currently 3GPP RAN1 delegate. He managed, in 2000-2003 period, several consultancy projects for international Telecom Italia activities in Austria, Greece and Spain on UMTS planning. He was involved in several European research programs (COST, ACTS, IST) dedicated to 3G and future mobile systems. He has published several papers on third and future generation mobile systems, smart antennas, SWradios and Cognitive Radios. Since 2003, he has managed the R&D projects dedicated to ‘Systems beyond 3G’ including TILab E2R I & II and E3 activities.
8 Σεπτεμβρίου 2008 (Δευτέρα 18:00)
Ομιλητής: Prof. Oriol Sallent
"Spectrum Assignment and Access in Future Cognitive Wireless Networks:
Some Envisaged Enablers and Solutions"
Wireless technologies are rapidly evolving in order to allow operators to deliver more advanced multimedia services. Furthermore, the regulatory perspective on how the spectrum should be allocated and utilized in a complex and composite technology scenario is evolving towards a cautious introduction of more flexibility in spectrum management together with economic considerations on spectrum trading. The multiplicity of Radio Access Technologies (RATs) and network operators, their different characteristics and the flexibility in spectrum management point out a challenging scenario that introduces relevant opportunities to increase efficiency. Certainly, the heterogeneous wireless network vision may be realized in a number of techno, regulatory and business scenarios, which will require diverse solutions and technologies for a proper exploitation of such opportunities. In any case, the framework envisaged above can only be fully accomplished by further enhancing the Radio Access Networks (RANs) towards Cognitive Network (CN) technologies. This talk will discuss several research challenges and present some technical solutions leading to an optimized utilization of the spectrum and radio resources.
Short CV: Oriol Sallent is Associate Professor at the Universitat Polit?cnica de Catalunya (UPC). His research interests are in the field of radio resource and spectrum management for heterogeneous cognitive wireless networks, where he has published 100+ papers in IEEE journals and conferences. He has participated in many research projects and consultancies funded by either public organisations or private companies. He is currently participating in E3 project within the 7th Framework Program of the European Commission.
ΠΡΟΓΡΑΜΜΑΤΑ ΟΜΙΛΙΩΝ ΑΛΛΩΝ ΕΤΩΝ