British art show 7: in the days of the comet

Exhibit: Karin Ruggaber’s wall-based Relief #90 presents an arrangement of tile-like forms resembling finds from an archaeological dig. Made from an amalgam of natural and man-made materials – shredded tree bark, concrete and plaster – each component part is cast using a process that produces unpredictable outcomes. Assembled on the wall, the individual parts engage with and activate empty space, while sometimes repeating, copying or mirroring each other. As Ruggaber comments, the work is ‘a kind of tableau, and in this sense it contains and plays with the elements of scenery, such as a focal point, background and foreground.’ Karin Ruggaber's Relief No 90 is an array of small painted sculptures, or sculpted paintings, each with its imprecise suggestion of a form – palettes, clogs, violins, crescent moons – hints from the real world and with the real world carried in their surfaces, from tree bark to pebble and moss. Dancing across the wall, they invoke small objects in rhythm and yet at the same time the turning world itself, the ground beneath one's feet; as beautifully ordered as the words in a sonnet

Sisyphean Task or the Holy Grail? Satisfying Demands of Higher Education through Community-Driven Open Source Projects

What elements are essential to successful community-driven open source projects? How much governance and overhead is required to develop and sustain an open source project? What are the factors that enhance or limit the pace of development, the growth in the development community, community adoption and longevity? Many open source projects don't start out worrying about sustainability or longevity, but successful projects often require considerable effort to succeed over time. This presentation and panel discussion will explore the use of community-driven open source projects to achieve the needs in higher education and review some of the many factors that may influence viability for community-driven open source projects. Specific projects will be discussed, along with a description of incubation strategies, governance approaches, growth challenges, ongoing support models, sustaining vibrant developer communities and lessons learned

Psychedelica: constellation lamp

A unique work created for Psychedelica generously donated by the artist Karin Ruggaber. “Constellation lamp presents a customised arche lamp with 7 floor-based relief pieces arranged in a precise yet open configuration around the pivot of lamp’s radius. The piece is touching on the symbolism and circularity of zodiac constellations as a means to map and locate.” Karin Ruggaber makes sculpture as well as producing artist’s books. She works with a range of materials and media, considering materials in relation to their dynamic and association with particular activities, or representational function

A Novel Kalman Filter Design and Analysis Method Considering Observability and Dominance Properties of Measurands Applied to Vehicle State Estimation

In Kalman filter design, the filter algorithm and prediction model design are the most discussed topics in research. Another fundamental but less investigated issue is the careful selection of measurands and their contribution to the estimation problem. This is often done purely on the basis of empirical values or by experiments. This paper presents a novel holistic method to design and assess Kalman filters in an automated way and to perform their analysis based on quantifiable parameters. The optimal filter parameters are computed with the help of a nonlinear optimization algorithm. To determine and analyze an optimal filter design, two novel quantitative nonlinear observability measures are presented along with a method to quantify the dominance contribution of a measurand to an estimate. As a result, different filter configurations can be specifically investigated and compared with respect to the selection of measurands and their influence on the estimation. An unscented Kalman filter algorithm is used to demonstrate the method’s capabilities to design and analyze the estimation problem parameters. For this purpose, an example of a vehicle state estimation with a focus on the tire-road friction coefficient is used, which represents a challenging problem for classical analysis and filter parameterization

Klausurtagung des Instituts für Telematik. Schloss Dagstuhl, 29. März bis 1. April 2000

Der vorliegende Bericht gibt einen Überblick über aktuelle Forschungsarbeiten des Instituts für Telematik an der Universität Karlsruhe (TH). Das Institut für Telematik ist in einem Teilgebiet der Informatik tätig, welches durch das Zusammenwachsen von Informatik und Kommunikationstechnik zur Telematik geprägt ist. Es gliedert sich in die Forschungsbereiche Telematik, Telecooperation Office (TecO), Cooperation & Management, Hochleistungsnetze und Netzwerkmanagement sowie dezentrale Systeme und Netzdienste. Die Schwerpunkte des Forschungsbereichs "Telematik" (Prof. Dr. Dr. h.c. mult. G. Krüger) liegen in den Bereichen "Dienstgüte", "Mobilkommunikation" und "Verteilte Systeme". Gemeinsames Ziel ist die Integration heterogener Netze (Festnetze und Funknetze), Rechnersysteme (von Workstations bis zu PDAs) und Softwarekomponenten, um damit den Anwendern eine Vielzahl von integrierten Diensten effizient und mit größtmöglicher Qualität zu erbringen. Das "Telecooperation Office" (TecO, Prof. Dr. Dr. h.c. mult. G. Krüger) ist ein Institutsbereich, der in Zusammenarbeit mit der Industrie anwendungsnahe Forschungsthemen der Telematik aufgreift. Im Mittelpunkt steht die innovative Nutzung von Kommunikationsinfrastrukturen mit den Schwerpunkten Softwaretechnik für Web-Anwendungen, neue Formen der Telekooperation sowie tragbare und allgegenwärtige Technologien (Ubiquitous Computing). Die Kernkompetenz des Forschungsbereichs "Cooperation & Management" (Prof. Dr. S. Abeck) liegt im prozessorientierten Netz-, System- und Anwendungsmanagement. Es werden werkzeuggestützte Managementlösungen für Betriebsprozesse entwickelt und in realen Szenarien erprobt. Ein wichtiges Szenario stellt das multimediale Informationssystem "NEXUS" dar, das als Plattform eines europaweit verteilten Lehr- und Lernsystems genutzt wird. Der Forschungsbereich "Hochleistungsnetze & Netzwerkmanagement" (Prof. Dr. W. Juling) befasst sich mit Technologie und Konzepten moderner leistungsfähiger Netzwerke sowie darüber hinaus mit sämtlichen Aspekten des Managements dieser zumeist ausgedehnten Netze. Um eine enge Abstimmung zwischen Forschungsaktivitäten und betrieblicher Praxis zu erzielen, werden insbesondere auch Synergien zwischen Institut und Rechenzentrum angestrebt. Die Arbeiten des Forschungsbereichs "Dezentrale Systeme und Netzdienste" (Prof. Dr. L. Wolf) befassen sich mit der Unterstützung verteilter Multimedia-Systeme, auch unter Berücksichtigung von Komponenten mit drahtlosem Zugang und den dafür geeigneten Architekturen und Infrastrukturen. Dabei werden vor allem Aspekte der Kommunikationssysteme wie Protokollmechanismen, Ressourcenverwaltung und adaptive und heterogene Systeme untersucht

Dynamics of particle clouds related to open-water sediment disposal

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000.Includes bibliographical references (p. 235-241).Open-water disposal and capping is a promising solution for disposing of the 14 to 28 million m3 of contaminated sediment dredged annually in the United States (National Research Council, 1997). Such practice raises concerns about the feasibility of accurately placing the material in a targeted area and the loss of material to the environment during disposal. To better predict the fate of these materials, the objective of this research was to gain new insight into the physical processes governing the mechanics of their convective descent. Instantaneously released sediments form axisymmetric "clouds" resembling selfsimilar thermals. Current particle cloud models employ thermal theory and an integral approach using constant entrainment (a), drag (CD), and added mass (k) coefficients. The aim of this study was to investigate how real sediment characteristics (particle size, water content, and initial momentum) affect cloud behavior (i.e., velocity, growth rate, and loss of particles) and time variations in a, CD, and k. Flow visualization experiments were conducted using a glass-walled tank, special sediment release and capture (i.e., "trap") mechanisms, and various cohesive and non-cohesive particles. Particle sizes were scaled to real-world dimensions through the cloud number (Nc), defined as the ratio of the particle settling velocity to the characteristic cloud velocity. An "inverse" integral model was developed in which the conservation equations were solved for a and k using measured velocity and radius data. Based on the "inverse" model results, particle cloud experiments were simulated with an integral model using constant and time-varying a and k. The non-cohesive sediments evolved rapidly into "thermals" with asymptotic deceleration and large growth rates (a = 0.2 - 0.3). The particles eventually organized into "circulating thermals," with linear growth rates obeying buoyant vortex ring theory. In this phase, large particles (Nc > 10-) produced laminar-like vortex rings with small a (0.1 - 0.2). Compared to the cohesive sediments, which exhibited a wide range of growth rates, changes in water content and initial momentum of the non-cohesive particles produced 10 - 20 % variations in a. Material not incorporated into the cloud upon release formed a narrow "stem" behind the cloud, which contained as much as 30 % of the original mass depending on the release conditions. Much of the "stem" material either re-entrained into the cloud later in descent or reached the bottom shortly after it. Material not incorporated into the "stem," which may be advected by ambient currents, was found to be only a small fraction ( 10-4) increased k to a value similar to that of a solid sphere. Integral model results confirm the suitability of using constant coefficients for modeling particle clouds with Nc less than 10-. When Nc is greater than 10-4, time-varying a and k are required to properly simulate cloud behavior in the "circulating thermal" phase.by Gordon J. Ruggaber.Ph.D

Architektur vernetzter Systeme. Seminar

This technical report comprises student papers within assignments for the seminar ``Architektur vernetzter Systeme\u27\u27. It took place at the Institute of Telematics of the University of Karlsruhe in summer 1999. Main topics for discussion contained CORBA extensions, tools and systems for mobile applications and also optimization concepts for large distributed systems

Implementation of a C Library of Kalman Filters for Application on Embedded Systems

Having knowledge about the states of a system is an important component in most control systems. However, an exact measurement of the states cannot always be provided because it is either not technically possible or only possible with a significant effort. Therefore, state estimation plays an important role in control applications. The well-known and widely used Kalman filter is often employed for this purpose. This paper describes the implementation of nonlinear Kalman filter algorithms, the extended and the unscented Kalman filter with square-rooting, in the programming language C, that are suitable for the use on embedded systems. The implementations deal with single or double precision data types depending on the application. The newly implemented filters are demonstrated in the context of semi-active vehicle damper control and the estimation of the tire–road friction coefficient as application examples, providing real-time capability. Their per-formances were evaluated in tests on an electronic control unit and a rapid-prototyping platform