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Erinnerung: Vortrag am 15.10.2007, 16:00 Uhr
by Informatik-Kolloquium 14 Oct '07

14 Oct '07

Die Dozenten der Informatik-Institute der Technischen Universität Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem Vortrag ein: Clemens Kupke, CWI Universität Amsterdam: Observational equivalence between coalgebras over Set Beginn: 15.10.2007, 16:00 Uhr Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23, 3. OG, Raum 305 Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-10-15-kupke.html Kontakt: Prof. Dr. Jirí Adámek Coalgebras provide a framework for studying various types of transition systems in a uniform way. In particular the theory of coalgebras yields for a given type of transition system a notion of "observational equivalence". In case the systems under consideration can be represented as coalgebras for a weak pullback preserving set functor F, observational equivalence can be nicely captured using the so-called "F-bisimulations". In my talk I want to focus on observational equivalence between coalgebras for functors that lack this property. For these functors I will propose so-called "relational equivalences" (a notion based on pushouts) as a useful generalization of F-bisimulations. In the first part of my talk I want to motivate why coalgebras for functors that do not preserve weak pullbacks are interesting by taking a closer look at neighbourhood frames. In coalgebraic terms, a neighbourhood frame is a coalgebra for the contravariant powerset functor composed with itself, i.e., a coalgebra for a functor that does not preserve weak pullbacks. I will discuss observational equivalence between neighbourhood frames in detail and finally sketch how to obtain a Van Benthem characterisation theorem for classical modal logic: over the class of neighbourhood frames classical modal logic can be seen as the fragment of first-order logic that is invariant under observational equivalence. In the second part of the talk I want to argue why, in my opinion, relational equivalences are a useful generalization of coalgebraic bisimulations. We characterize those set functors F for which every observational equivalence between F-coalgebras is a relational equivalence.

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Vortrag am 15.10.2007, 16:00 Uhr
by Informatik-Kolloquium 11 Oct '07

11 Oct '07

Die Dozenten der Informatik-Institute der Technischen Universität Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem Vortrag ein: Clemens Kupke, CWI Universität Amsterdam: Observational equivalence between coalgebras over Set Beginn: 15.10.2007, 16:00 Uhr Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23, 3. OG, Raum 305 Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-10-15-kupke.html Kontakt: Prof. Dr. Jirí Adámek Coalgebras provide a framework for studying various types of transition systems in a uniform way. In particular the theory of coalgebras yields for a given type of transition system a notion of "observational equivalence". In case the systems under consideration can be represented as coalgebras for a weak pullback preserving set functor F, observational equivalence can be nicely captured using the so-called "F-bisimulations". In my talk I want to focus on observational equivalence between coalgebras for functors that lack this property. For these functors I will propose so-called "relational equivalences" (a notion based on pushouts) as a useful generalization of F-bisimulations. In the first part of my talk I want to motivate why coalgebras for functors that do not preserve weak pullbacks are interesting by taking a closer look at neighbourhood frames. In coalgebraic terms, a neighbourhood frame is a coalgebra for the contravariant powerset functor composed with itself, i.e., a coalgebra for a functor that does not preserve weak pullbacks. I will discuss observational equivalence between neighbourhood frames in detail and finally sketch how to obtain a Van Benthem characterisation theorem for classical modal logic: over the class of neighbourhood frames classical modal logic can be seen as the fragment of first-order logic that is invariant under observational equivalence. In the second part of the talk I want to argue why, in my opinion, relational equivalences are a useful generalization of coalgebraic bisimulations. We characterize those set functors F for which every observational equivalence between F-coalgebras is a relational equivalence.

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Erinnerung: Vortrag am 11.10.2007, 16:00 Uhr
by Informatik-Kolloquium 10 Oct '07

10 Oct '07

Die Dozenten der Informatik-Institute der Technischen Universität Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem Vortrag ein: Prof. Takahiro Kiuchi, M.D., Ph.D., Department of Health Communication, School of Public Health, University of Tokyo: UMIN - Concept, History, and Current Status Beginn: 11.10.2007, 16:00 Uhr Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23, 4. OG, Raum 435 Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-10-11-kiuchi.html Kontakt: Prof. Dr. Reinhold Haux University hospital Medical Information Network (UMIN), Japan, was established in 1989 to share common database and application software among national university hospitals in Japan. Thanks to its successful management and successive funding from the government, UMIN has evolved into one of the largest and most versatile public academic network organizations in the world and indispensable information infrastructure for the Japanese medical academic community. Currently, the number of its registered medical professionals and its web page views per month is about 153,000 and 15,000,000, respectively. I believe that similar public information centers for academic activities would be also beneficial for other academic specialties in other countries.

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Erinnerung: Vortrag am 07.10.2007, 11:15 Uhr
by Informatik-Kolloquium 06 Oct '07

06 Oct '07

Die Dozenten der Informatik-Institute der Technischen Universität Braunschweig machen auf folgenden Vortrag der GI Regionalgruppe Braunschweig aufmerksam: GI/VDI-Workshop: Jasmin Ramm, M.A., BLM: »Grimme, Natalis und Co.« gegen die »geisttötende Kopfarbeit« Beginn: 07.10.2007, 11:15 Uhr Ort: Braunschweigisches Landesmuseum, Burgplatz 1 Webseite: http://tg.vdi-bs.de/?content=2&showDate=51 Kontakt: Besondere Rechenmaschinen mehrerer Jahrhunderte aus der Sammlung des Braunschweigischen Landesmuseums werden den Teilnehmern des Workshops in Anwendung und Funktionsweise durch Frau Ramm vorgestellt, so z.B. ein Nachbau der Rechenuhr von Wilhelm Schickard, das Arithmomètre von Charles-Xavier Thomas und verschiedene Brunsviga-Modelle. Ein besonderer Leckerbissen ist sicher dabei, dass die Teilnehmer verschiedene historische Rechenmaschinen in Funktion erleben werden und vorher mit einer Führung durch die Dauerausstellung des Braunschweigischen Landesmuseums Einblicke in die Geschichte des Braunschweiger Unternehmens »Grimme, Natalis und Co.« und seinen Wandel zum Rechenmaschinenproduzenten »Brunsviga Maschinenwerke A.G.« erhalten können. Dieser Workshop aus der VDI-Vortragsreihe "Diagonale" wird gemeinsam mit dem Braunschweigischen Landesmuseum im Rahmen der Stadt der Wissenschaft 2007 veranstaltet. Eine vorherige Anmeldung ist erforderlich. Die Teilnehmerzahl ist auf 25 Personen begrenzt. Der Eintritt wird vom VDI Braunschweig übernommen. Anmeldung unter Tel. 0531 / 1215-2632 (9.00 - 16.00 Uhr)

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Vortrag am 11.10.2007, 16:00 Uhr
by Informatik-Kolloquium 02 Oct '07

02 Oct '07

Die Dozenten der Informatik-Institute der Technischen Universität Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem Vortrag ein: Prof. Takahiro Kiuchi, M.D., Ph.D., Department of Health Communication, School of Public Health, University of Tokyo: UMIN - Concept, History, and Current Status Beginn: 11.10.2007, 16:00 Uhr Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23, 4. OG, Raum 435 Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-10-11-kiuchi.html Kontakt: Prof. Dr. Reinhold Haux University hospital Medical Information Network (UMIN), Japan, was established in 1989 to share common database and application software among national university hospitals in Japan. Thanks to its successful management and successive funding from the government, UMIN has evolved into one of the largest and most versatile public academic network organizations in the world and indispensable information infrastructure for the Japanese medical academic community. Currently, the number of its registered medical professionals and its web page views per month is about 153,000 and 15,000,000, respectively. I believe that similar public information centers for academic activities would be also beneficial for other academic specialties in other countries.

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Vortrag Benny Bing (Georgia Tech, USA): "Pervasive Broadband Wireless Access"
by Lars Wolf 28 Sep '07

28 Sep '07

TELECOM SEMINAR Benny Bing, Georgia Tech, USA Pervasive Broadband Wireless Access Freitag, 5. Okt. 2007, um 16:00 Uhr Seminarraum @ IDA, Zimmer 1111, Hans-Sommer-Str. 66 ABSTRACT Broadband wireless access is the third wireless revolution, after cellphones (1990s) and Wi-Fi (2000s). It is viewed by many carriers and cable operators as a “disruptive” technology and rightly so. The broadcast nature of wireless transmission offers ubiquity and immediate access for both fixed and mobile users, clearly a vital element of next-generation quadruple play (i.e., voice, video, data, and mobility) services. Unlike wired access (copper, coax, fiber), a large portion of the deployment costs is incurred only when a subscriber signs up for service. An increasing number of municipal governments around the world are financing the deployment of multihop wireless networks with the overall aim of providing ubiquitous Internet access and enhanced public services. This talk will provide a comparative assessment of the key standards and technologies underpinning promising broadband wireless access solutions. Key standards include 802.16 (Wi-Max), long-range/multihop 802.11 (Wi-Fi), wireless DOCSIS, 3G/4G/LTE, mobile digital TV broadcast (DVB-H, MediaFLO), 802.20 (mobile broadband), 802.21 (media independent handoff and interoperability), and the emerging 802.22 (wireless regional area networks) standard. Key technologies include licensed and unlicensed spectrum consideration; reliable physical layer transmission using multiple antennas; wireless access topologies; wireless multimedia services; mobility; cognitive radio technologies; advanced wireless security; fixed-mobile convergence. Biography Benny Bing is a research faculty member with the School of ECE at the Georgia Institute of Technology. He has published 50 technical papers and 10 books. He is an editor for the IEEE Wireless Communications Magazine and has guest edited for the IEEE Communications Magazine (2 issues) and the IEEE Journal on Selected Areas on Communications. In October 2003, he was invited by the NSF to participate in a workshop on Residential Broadband. He is a Senior Member of IEEE and an IEEE Communications Society Distinguished Lecturer. - Kuchen und Kaffee nach dem Vortrag. Prof. Admela Jukan <jukan(a)ida.ing.tu-bs.de>

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Erinnerung: Vortrag am 27.09.2007, 19:00 Uhr
by Informatik-Kolloquium 26 Sep '07

26 Sep '07

Die Dozenten der Informatik-Institute der Technischen Universität Braunschweig machen auf folgenden Vortrag der GI Regionalgruppe Braunschweig aufmerksam: GI/VDI-Vortrag: Dr. Horst Zuse, Berlin: Der Ursprung des Computers Beginn: 27.09.2007, 19:00 Uhr Ort: Braunschweigisches Landesmuseum, Burgplatz 1 Webseite: http://tg.vdi-bs.de/?content=2&showDate=42 Kontakt: Es hat vieler hervorragender Wissenschaftler, Ingenieure und Manager weltweit bedurft, um den Computer zu der heutigen Verbreitung zu verhelfen. Charles Babbage (1792-1871) formulierte die ersten Grundideen von programmgesteuerten Rechenmaschinen. Konrad Zuse (1910-1995) wird heute fast einhellig auf der ganzen Welt als Schöpfer des ersten frei programmierbaren Rechners in binärer Schalttechnik und Gleitpunktrechnung, der wirklich funktionierte, anerkannt. Kurzum, er baute den ersten funktionsfähigen Digitalrechner. Heute bezeichnen wir solche Maschinen als Computer. In diesem Vortrag werden u.a. die Rechnerentwicklungen von Charles Babbage, George Stibitz, Vincent Atanasoff, Howard Aiken, die ENIAC und das bis 1977 geheime COLOSSUS-Projekt (Dekodierung der Funksprüche der Deutsche Wehrmacht, ab 1943) in UK vorgestellt. Die frühen Rechenmaschinen Z1-Z4 (1936-1945) von Konrad Zuse werden mit vielen, teils noch nie gezeigten Bildern und Videos präsentiert. Dargestellt wird aber auch die Computerproduktion der Zuse KG, die von 1949-1969 250 Computer im Wert von 102 Millionen DM produzierte. Dieser Vortrag aus der VDI-Vortragsreihe "Diagonale" wird gemeinsam mit dem Braunschweigischen Landesmuseum im Rahmen der Stadt der Wissenschaft 2007 veranstaltet.

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Biswanath Mukherjee (UC davis, USA): Implications of Emerging Optical Technologies on Future Internet
by Lars Wolf 18 Sep '07

18 Sep '07

Folgender Vortrag mag auch für einige Mitlgieder dieser Mailing-Liste von Interesse sein. INSTITUT FÜR DATENTECHNIK UND KOMMUNIKATIONSNETZE TELECOM SEMINAR Biswanath Mukherjee, Child Family Endowed Chair Professor University of California, Davis, USA Implications of Emerging Optical Technologies on Future Internet Donnerstag, 20. Sept. 2007, um 11:00 Uhr Seminarraum @ IDA, Zimmer 1111, Hans-Sommer-Str. 66 Kontakt: Prof. Dr. Admela Jukan ABSTRACT In this talk, we will articulate research opportunities and challenges in terms of Future Internet design, as influenced by emerging optical technologies and networks. Our emphasis will NOT be about technologies or narrowly-focused research. Instead, the talk will be about the broad perspective of how these technologies -- and their expected rapid development -- might affect the larger overall network architecture, and vice versa. Biography Biswanath Mukherjee (S'82--M'87--F'07) received the B.Tech. (Hons) degree from Indian Institute of Technology, Kharagpur (India) in 1980 and the Ph.D. degree from University of Washington, Seattle, in June 1987. In July 1987, he joined the University of California, Davis, where he has been Professor of Computer Science since July 1995 (and currently holds the Child Family Endowed Chair Professorship), and served as Chairman of the Department of Computer Science during September 1997 to June 2000. He serves or has served on the editorial boards of the IEEE/ACM Transactions on Networking,IEEE Network, ACM/Baltzer Wireless Information Networks (WINET), Journal of High-Speed Networks, Photonic Network Communications, Optical Network Magazine, and Optical Switching and Networking. He served as Editor-at-Large for optical networking and communications for the IEEE Communications Society; as the Technical Program Chair of the IEEE INFOCOM '96 conference; and as Chairman of the IEEE Communication Society's Optical Networking Technical Committee (ONTC) during 2003-05. Mukherjee is author of the textbook "Optical WDM Networks" published by Springer in January 2006. Earlier, he authored the textbook "Optical Communication Networks" published by McGraw-Hill in 1997, a book which received the Association of American Publishers, Inc.'s 1997 Honorable Mention in Computer Science. He is a Member of the Board of Directors of IPLocks, Inc., a Silicon Valley startup company. - Kuchen und Kaffee nach dem Vortrag.

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Erinnerung: Vortrag am 04.09.2007, 10:00 Uhr
by Informatik-Kolloquium 03 Sep '07

03 Sep '07

Die Dozenten der Informatik-Institute der Technischen Universität Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem Vortrag ein: Dr. David Frey, Washington University, St. Louis, USA: Addressing the Challenges of Publish-Subscribe in Dynamic Network Environments Beginn: 04.09.2007, 10:00 Uhr Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23, 1. OG, Hörsaal M 161 Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-09-04-frey.html Kontakt: Prof. Dr. Sándor P. Fekete The publish-subscribe communication paradigm is enjoying increasing popularity thanks to its ability to simplify the development of complex distributed applications. However, many existing solutions in the publish-subscribe domain address only part of the challenges associated with the design of applications for dynamic scenarios such as mobile ad hoc or peer-to-peer networks. This talk presents my work aimed at addressing these limitations with novel protocols that allow publish-subscribe middleware to support unexpected disconnections, mobility, and context-aware interactions. I start by introducing the publish-subscribe model and presenting a general-purpose reactive solution that addresses dynamicity through the reconfiguration of the event dispatching infrastructure. I then complete the picture by presenting a context-aware extension to the model and by describing a geocast-based protocol that exploits context information to control the dissemination of events in a mobile ad hoc network. Biographical Note: David Frey received his Laurea Degree in Computer Engineering from Politecnico di Milano in 2002. In May 2006, he received his PhD in Computer Engineering also from Politecnico di Milano. He then spent a year as a visiting researcher in the Mobile Computing Laboratory at Washington University in St Louis, MO, USA. His main research interests are in the design and analysis of distributed protocols for dynamic network scenarios such as large-scale peer-to-peer systems and mobile ad hoc networks.

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Raumaenderung: Vortrag am 04.09.2007, 10:00 Uhr
by Informatik-Kolloquium 30 Aug '07

30 Aug '07

Die Dozenten der Informatik-Institute der Technischen Universität Braunschweig laden im Rahmen des Informatik-Kolloquiums zu folgendem Vortrag ein: Dr. David Frey, Washington University, St. Louis, USA: Addressing the Challenges of Publish-Subscribe in Dynamic Network Environments Beginn: 04.09.2007, 10:00 Uhr Ort: TU Braunschweig, Informatikzentrum, Mühlenpfordtstraße 23, 1. OG, Hörsaal M 161 Webseite: http://www.ibr.cs.tu-bs.de/cal/kolloq/2007-09-04-frey.html Kontakt: Prof. Dr. Sándor P. Fekete The publish-subscribe communication paradigm is enjoying increasing popularity thanks to its ability to simplify the development of complex distributed applications. However, many existing solutions in the publish-subscribe domain address only part of the challenges associated with the design of applications for dynamic scenarios such as mobile ad hoc or peer-to-peer networks. This talk presents my work aimed at addressing these limitations with novel protocols that allow publish-subscribe middleware to support unexpected disconnections, mobility, and context-aware interactions. I start by introducing the publish-subscribe model and presenting a general-purpose reactive solution that addresses dynamicity through the reconfiguration of the event dispatching infrastructure. I then complete the picture by presenting a context-aware extension to the model and by describing a geocast-based protocol that exploits context information to control the dissemination of events in a mobile ad hoc network. Biographical Note: David Frey received his Laurea Degree in Computer Engineering from Politecnico di Milano in 2002. In May 2006, he received his PhD in Computer Engineering also from Politecnico di Milano. He then spent a year as a visiting researcher in the Mobile Computing Laboratory at Washington University in St Louis, MO, USA. His main research interests are in the design and analysis of distributed protocols for dynamic network scenarios such as large-scale peer-to-peer systems and mobile ad hoc networks.

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