In recent years, point primitives have received a growing attention in computer graphics. There are two main reasons for this new interest in points: On one hand, we have witnessed a dramatic increase in the polygonal complexity of computer graphics models. The overhead of managing, processing, and manipulating very large polygonal meshes has led many researchers to question the future utility of polygons as the fundamental graphics primitive. On the other hand, modern 3D digital photography and 3D scanning systems facilitate the ready acquisition of complex, real-world objects. These techniques generate huge volumes of point samples and create the need for advanced point processing.

Conceptually, points constitute the atomic digital building blocks of object geometry and appearance - much as pixels form the digital elements of 2D images. In spite of the great challenges point samples pose to graphics processing, the latest generation of algorithms includes advanced modeling, sophisticated geometry processing, and high quality rendering.

In this talk I will introduce points as a powerful and versatile graphics primitive and present a survey the latest research results in point based graphics. Novel concepts for the representation of point sampled shapes will be discussed, as well as algorithms for interactive modeling of point clouds. In addition, I will address methods for geometric processing, filtering, and resampling of point models. I will also give examples of algorithms for high performance rendering of point clouds, including advanced shading, antialiasing, and transparency.

Finally, I will introduce Pointshop3D, an Open Source framework for 3D photo editing of point sampled geometry.

While high-speed wireless access is easy to achieve in an enterprise network via low-cost IEEE 802.11 (WiFi) access points, wireless technology in public spaces is in its infancy. ``Hot spots'' provide high-speed wireless access, but do so in very few isolated ``islands'' at immense costs. Likewise, while fixed wireless and 3G can provide ubiquitous coverage and 3G can support mobility, throughputs can often be two orders of magnitude slower than WiFi. In this talk, I will make the case for the requirement of a fundamental new architecture based on beamforming antennas deployed on fixed, Transit Access Points (TAPs) that form a multi-hopping wireless backbone with a limited number of wired ingress/egress points. Moreover, I will describe a number of research issues including opportunistic and coordinated resource management and challenges in achieving fairness.

Edward Knightly is an associate professor in the ECE and CS Departments at Rice University. He received the B.S. degree from Auburn University in 1991 and the M.S. and Ph.D. degrees from the University of California at Berkeley in 1992 and 1996 respectively. He is an associate editor of the Computer Networks Journal and IEEE/ACM Transactions on Networking, and previously, IEEE Transactions on Multimedia and IEEE Network Magazine. He served as co-chair of IWQoS 1998 and on the steering committee for IWQoS from 1999-2001. He served as finance chair for ACM MOBICOM 2002 and 2003, tutorial co-chair for IEEE ICNP 2001 and MOBIHOC 2003, and on the program committee for numerous networking conferences including ICNP, INFOCOM, IWQoS, MOBICOM, and SIGMETRICS. He received the National Science Foundation CAREER Award in 1997 and the Sloan Fellowship in 2001. He is the technical co-chair of INFOCOM 2005. His research interests are in the areas of mobile and wireless networks, high-performance protocol design, quality of service, and performance evaluation.

Visual motion is one of the most important cues for every animal with eyes. It is used in many different contexts like visual course control, collision avoidance and structure-from-motion, to name just a few. However, visual motion information is not explicitly represented at the retina but instead has to be computed by the nervous system from the retinal images changing over time. We study this process of elementary motion detection in the fly which is a specialist in motion vision and has nerve cells large enough to allow for the application of various physiological techniques.

In this talk, I will first provide experimental evidence for a computational model of motion detection, the so-called Reichardt detector. Then, I will demonstrate that Reichardt detectors automatically adjust their velocity gain in response to changing statistics of the stimulus, by this way maximizing the information they transmit about the stimulus. Finally I will summarize our recent attempts to uncover the cellular implementation of Reichardt detectors using transgenic approaches in Drosophila.

Alexander Borst is Director of the Department of Systems and Computational Neurobiology, Max-Planck-Institute of Neurobiology, Germany.

Die Entwicklung neuer Informatikkonzepte wie Software-Agenten, Autonomic, Grid Pervasive Computing lässt einen deutlichen Trend zur Dezentralisierung erkennen. Damit ist es möglich, weltweit verfügbare Computerressourcen besser zu nutzen, eigennütziges wirtschaftliches Handeln der mobilen Netzteilnehmer zu automatisieren oder selbstorganisierende Informationssysteme zu erschaffen. Die Frage stellt sich jedoch, ob wir wir bald überall von automatischen IT-Systemen umgeben sein werden, die zwar im Detail nützlich und unverzichtbar werden, sich in ihrem Zusammenspiel jedoch einer menschlichen Kontrolle entziehen.

We shall present the Biochemical Abstract Machine BIOCHAM and advocate its use as a formal modeling environment for networks biology. Biocham provides a precise semantics to biomolecular interaction maps. Based on this formal semantics, the Biocham system offers automated reasoning tools for querying the temporal properties of the system under all its possible behaviors. We shall review the main features of Biocham and report on our modeling experience with this language. In particular we shall report on a model of the mammalian cell cycle's control developped after Kohn's map.

We are sorry to inform you that the colloquium of July 5 has to be canceled because the speaker, Mario Jeckle, died while trying to help at a car accident scene.
The CS Department offers its sympathies to the family of Mario Jeckle and to the FH Furtwangen, where he was a professor.

Die Aggregation verschiedener über Internet verbundener Ressourcen zu virtuellen Gesamtsystemen, welche die versammelte Einzelleistungsfähigkeit hinsichtlich Speicher- oder Berechnungskapazität gebündelt zur Verfügung stellen gewinnt derzeit unter dem Schlagwort "Grid Computing" immer mehr an Bedeutung. Dieser Trend wird durch sich stetic weiter vergünstigende Zugangskosten zum weltumspannenden Netz und der unablässigen Verbilligung verfügbarer Hardware, welche durch einen einzelnen Benutzer heute kaum mehr permanent ausgelastet werden kann, noch zusätzlich befördert. So werden freie selbstorganisierende Projekte wie "SETI@home", "Folding@home" oder "GIMPS" gegenwärtig von mehreren zehntausend verschalteter Maschinen vorangetrieben.

Darüberhinaus finden Grid-basierte Ansätze auch in der Industrie, etwa zur Simulation komplexer Schaltungsnetze, der Crash-Test-Berechnung in der Automobilindustrie oder zur Lösung logistischer Probleme wie Wegeoptimierung breites Interesse, da sie die kostengünstige Nutzung brachliegender Hardwareressourcen versprechen und so gleichzeitig dazu beitragen die Notwendigkeit der Anschaffung des Betriebs finanziell und technisch aufwendiger Superrechner- oder Clusterinstallationen verringern.

Die Nutzung der Ansätze und Standards aus dem Umfeld Web services gerät jedoch erst in jüngerer Zeit verstärkt in den Brennpunkt des Interesses der Schaffung einer leichtgewichtigen und gleichermaßen flexibel skalierbaren Basisinfrastruktur für Grid-Verbünde.