José L. Encarnação

Human-centered computing, online communities, and virtual environments

This report summarizes results of the first EC/NSF joint Advanced Research Workshop, which identified key research challenges and opportunities in information technology. The group agreed that the first joint research workshop should concentrate on the themes of human-centered computing and VEs. Human-centered computing is perceived as an area of strategic importance because of the move towards greater decentralization and decomposition in the location and provision of computation. The area of VEs is one where increased collaboration should speed progress in solving some of the more intractable problems in building effective applications.

Human-centered computing, online communities and virtual environments

This report summarizes results of the first EC/NSF joint Advanced Research Workshop, which identified key research challenges and opportunities in information technology.

Computer graphics education in Germany

Introduction During the last few years computer graphics education in Germany has expanded considerably. The institutions having computer graphics in their program are spread nearly uniformly all over Germany, although still not all universities offer this subject. Knowledge in computer graphics can be acquired in universities, technical schools (fachhochschule, in German) and private industrial organizations. In this contribution, we will restrict ourselves to universities and technical schools. Education in computer graphics usually forms part of a curriculum of a more general subject, mostly computer science (informatik). For that reason we will first explain the German system as a whole. Nationwide this system is quite uniform, but possibly the international reader of this article is not familiar with it. We will then describe the typical points of computer graphics education at universities, followed by those at technical schools. We will show how the education system is organized in general. The information is drawn from a general inquiry made in 1993 by the Special Interest Group of Computer Graphics within the German Socie ty of Compute r Science (Gese l l schaf t fuer In fo rmat ik (GI)), an organiza t ion s imi lar to the ACM. Accompanying tables compile some more detailed information on the institutions taking part. To our knowledge, the listings should be relatively complete, although of course this cannot be guaranteed.

A Survey of DB Requirements for Graphical Applications in Engineering

The problem of integrating the graphical and non-graphical information in one data base has not yet been adequately solved. The feasibility of solution has been shown in the literature (Williams, Giddings 76). This paper attempts to identify the specific features exhibited by graphical information structures as used in engineering application. It further focuses on the ways the users interact with the stored information, Bearing these features in mind, some requirements on data base management systems will be inferred.

Interactive graphics on intelligent terminals in a time-sharing environment

SummaryInteractive graphics in a time-sharing environment should be organized in such a way that the users activities are locally processed in order to avoid unacceptably long response times — especially if only low-speed communication links are available. On the other hand, the host computer must be kept informed about the users actions and, conversely, the display file in the terminal has to be updated whenever the execution of the application program cases a change in the visual representation. In order to avoid the transmission of redundancy, we decompose the display file into two intersecting parts such that the part in the host computer and the other in the terminal contains only the locally required information. The necessary communication between both parts is maintained by an information module generated on the base of a low-low-level intermediate language (L4) and exchanged between computer and terminal. This leads to the notion of an abstract terminal whose “machine language” is L4, facilitating the implementation and portability of graphic programming systems. The L4 concept and our experiences with its implementation is discussed.

Computer graphics in Germany

Introduction In Germany we are witnessing for some 20 years an increasing interest in computer graphics, animation, art, visualization and hardware. Initially in the ‘80s, the growth of computer graphics groups at German universities was slow. But then, sometime in the early ‘90s, a critical point-of-no-return was reached. Since then it seems as if every computer science department has been striving to install a graphics group, if it did not already have one. In addition, centers of research and development in computer graphics are operating within institutions that are funded publicly or by industry. A prominent example of the rapid development and joint activities of universities and research centers are the institutions located in Darmstadt. In 1975 Prof. Jose Encarnacao founded the Interactive Graphics System Group. To involve industrial partners in computer graphics research he established the Computer Graphics Center (ZGDV) in 1984. Three years later, the Fraunhofer Society opened its doors with a work group, which led to the Fraunhofer Institute for Computer Graphics. Since then, other institutions in Germany and abroad have joined what is now called the INI-GraphicsNet, one of the world’s largest research institutes in computer graphics (300 full time employees, 450 research assistants, DM 72 million budget in 2000). The prestigious Max-Planck-Gesellschaft founded a new research group on computer graphics within the Max-Planck-Institute of Computer Science on the campus of the University of the Saarland, headed by Prof. HansPeter Seidel. Also the Konrad-Zuse-Zentrum (ZIB) in Berlin hosts a strong visualization group. Two years ago the German Research Center for Artificial Intelligence (DFKI) founded a research institute for visualization and simulation headed by Prof. Hans Hagen. Other public institutions with computer graphics research activities include the German National Research Center for Information Technology (GMD), housing research groups with a focus on virtual environments and digital media productions.

User interfaces to support the design process

This paper will give a short overview of developments and methods in the area of graphical user interfaces. As an example a User Interface Management System (UIMS) as a dialogue design tool and an open CAD system with a graphical user interface will be described. These systems result from developments realized in Darmstadt by the Computer Graphics Center (ZGDV) and the Fraunhofer Computer Graphics Research Group (FhG-AGD). Under the perspective of integration of the different aspects, the possibilities to support the design process will be discussed. These aspects are to use methods of artificial intelligence, to unify the presentation of those methods, and to realize those processes in parallel.

CAD technology: a survey on CAD systems and applications

Abstract This paper discusses some of the basic issues in cad technology and the different aspects of cad applications running on workstations and on pc s. Advanced vlsi components, as well as prominent new architectures ( risc ) and their impact are presented in detail. Data transfer formats and the map protocol are further topics addressed. The characteristics of different cad applications and the role of networking in cad/cam applications are then discussed. The paper finishes with a consideration of trends and an extended bibliography.

e-Learning und Knowledge Management

In Zukunft werden Arbeitsprozesse zunehmend wissensbasiert durchgefuhrt werden. Daher werden der Wissensaustausch und die Verbesserung des Unternehmenswissens zu einem entscheidenden Wettbewerbsfaktor werden, der nur von Lernenden Organisationen uberdurchschnittlich erfullt werden kann. Lernende Organisationen sind Gruppen von Personen, die ihre Fahigkeiten und ihr gemeinsames Wissen kontinuierlich erweitern, um ihre Ziele als Organisation zu erfullen.

Distributed supercomputing to achieve real-time representation and manipulation of complex scenes

Abstract Besides the ray tracing technique, the radiosity method is another major approach for global illumination modeling in the field of computer graphics. Since this method needs a huge amount of storage space (both memory and disk) and a long pre-computation cycle, it is not suitable to implement it on conventional workstations. Supercomputers seem to be necessary for such kind of graphics applications. However, some problems appear with the integration of supercomputers and workstations in a distributed computing environment, especially for graphics application. The major problems are: (i) unavailability of standard higher-level mechanisms for building distributed application; (ii) transparent access to supercomputers without remote login or file transfer sessions; (iii) computation balance to make the best use of the performance of supercomputers and workstations; (iv) data transfer/storage strategy between supercomputers and workstations; and (v) conflict between interaction and response time for graphics applications. In this paper we suggest solutions to the above mentioned problems based on the remote procedure call (RPC) and the client/server model, for the radiosity package implementation. After the introduction of the radiosity method, we concentrate on the integration between supercomputers and high-performance workstations. We also convey some general issues related to distributed computing and present the experience with our implementation, such as the application protocol definition, error recovery, code debugging etc. The radiosity package has been implemented at ZGDV in Darmstadt, F.R.G. in a network environment including a Multiflow TRACE 7/300 supercomputer connected to several VAX, SUN and HP workstations.