Gerhard Joubert

Technische Universität Clausthal | TUC · Department of Computer Science

During the latter half of the 1970s high performance computers (HPC) were constructed using specially designed and manufactured hardware. The preferred architectures were vector or array processors, as these allowed for high speed processing of a large class of scientific/engineering applications. Due to the high cost of the development and constru...

The general concept of the scientific method or procedure consists in systematic observation, experiment and measurement, and the formulation, testing and modification of hypotheses. In many cases a hypothesis is formulated in the form of a model, for example a mathematical or simulation model. The correctness of a solution of a problem produced by...

This volume of the series “Advances in Parallel Computing” contains the proceedings of the International Conference on Parallel Programming – ParCo 2013 – held from 10 to 13 September 2013 in Garching, Germany. The conference was hosted by the Technische Universiät München (Department of Informatics) and the Leibniz Supercomputing Centre. With Par...

Virtualized cloud infrastructures are very popular as they allow resource mutualization and therefore cost reduction. For cloud providers, minimizing the number of used resources is one of the main services that such environments must ensure. Cloud customers ...

This volume of the book series “Advances in Parallel Computing” contains the proceedings of ParCo2011, the 14th biennial ParCo Conference, held from 31 August to 3 September 2011, in Ghent, Belgium. In an era when physical limitations have slowed down advances in the performance of single processing units, and new scientific challenges require exas...

This book series publishes research and development results on all aspects of parallel computing. Topics may include one or more of the following: high-speed computing architectures (Grids, clusters, Service Oriented Architectures, etc.), network technology, performance measurement, system software, middleware, algorithm design, development tools,...

Currently, software engineering is becoming even more complex due to distributed computing. In this new context, portability while providing the programmer with the single system image of a classical Java Virtual Machine (JVM) is one of the key issues. Hence a cluster-aware JVM, which can transparently execute Java applications in a distributed fas...

In video object tracking, shadows are commonly present for general lighting environments and present a confounding factor for correct object tracking. Tracking the real object instead of a compound object with shadow is a challenging problem. Therefore object tracking results based on traditional schemes usually result in a combination of the objec...

The new computational technologies are having a very strong influence on numerical optimization, in several different ways. Many researchers have been stimulated by the need to either conform the existing numerical techniques to the new parallel architectures ...

Multimedia systems integrate time dependent and time independent media. This makes their development significantly more complex than that of conventional information processing systems. Standard paradigms for system development do not satisfactorily model multimedia system development processes. In this paper a new flexible project management model...

Image retrieval with dynamically extracted features compares user-defined regions of interest with all sections of the pictures stored in an image database. Thereby, objects regardless of the actual pictorial environment are of interest. This paper discusses an application of Gabor-Wavelet-Networks as a solution of the object-based search. In contr...

This paper presents a technique to locate straight image features to sub-pixel accuracy using under-sampled imagery, whereby it is assumed that the approximate location was previously determined by an arbitrary edge detection filter. The approach requires the a-priori knowledge of the acquisition system's point spread function and computes the solu...

: Due to the development of e-commerce/e-business combined with global marketing strategies, the way in which products and services are advertised changed dramatically. In the transition from brick-and-mortar-business to e-business, the classic approach of advertising in newspapers, on TV and radio, etc. was firstly complemented with CD-ROMs. Due t...

1 : In this paper new ideas and algorithms for adapting the workflow for newscast production are presented. The goal is to enable TV news editors to take advantage of the added facilities offered by digital video techniques. Algorithms for the analysis of MPEG compressed videos are presented. These enable a news editor to extract sequences of key f...

. In this paper methods for analysing and processing digitised compressed video newsfeeds are discussed. Due to computing, storage and communication limitations the material has to be processed in compressed form. This creates particular problems which are not encountered when decompressed video material is handled. The methods described allow news...

1 : In this paper an iterative algorithm for extraction of key frames from digitised MPEG-1 compressed newsfeeds is introduced. Newsfeeds consist of assembled news clips transmitted by news agencies. These are usually recorded in analogue form by subscribing TV stations. Editors analyse the video material through a sequential and time intensive sea...

The increasing use of digital images in applications ranging from remote sensing to medical applications and industrial control systems results in a demand for well-suited and efficient techniques for their storage, management and retrieval. The state-of-the-art approach for image retried considers a priori extracted features, which are compared to...

Distributed platforms are not necessarily well-suited for systems which handle large data sets, such as processed in multimedia applications. In this paper a specialised computation model, based on asynchronous transmission, is presented. As the necessary functions are encapsulated this system can be used without detailed knowledge of the system ar...

In this paper a specialised search engine for TV news editors as part of a system for analysis and presentation of MPEG compressed newsfeeds is discussed. The editor is supplied with additional material relating to particular news items, which he can, for example, use to prepare the accompanying text of newscasts. The key words for the search engin...

The use of multimedia systems can greatly improve the communication of users with complex systems through the use of additional information representations. Media used in such systems often include still and moving images. These generate large data volumes which make image compression techniques are sensitive to noise in images. In this paper noise...

This chapter reviews that modern high speed computers make it possible to solve large and complex problems. Owing to the continuing increase in compute speeds the complexity and size of problems that can be treated, increases. Techniques, such as graphical user interfaces and data visualization methods, can greatly facilitate user interaction with...

Multimedia technologies will revolutionise the way in which information processing is done. In order to develop multimedia applications, powerful processors and high-speed communication networks will have to be installed. In order to develop and maintain multimedia systems, new software and information engineering methods and tools must be develope...

A MIMD parallel computer constructed by linking two minicomputers with a high-speed communication cable is considered. In this system there is no common shared memory available and the synchronization of the parallel processes must be done through software. When solving a specific problem or class of problems with such a computer, the accent should...

The need to run large, compute-bound programs encountered in research, coupled with the high availability of mini- and microcomputers in the laboratory environment, has prompted the linking of independent processors to form multicomputer systems. Important characteristics of the system presented here are the lack of shared memory between processors...

The solution of differential equations often requires extensive computation time on serial digital computers. In order to reduce overall computation times for such compute bound problems, parallel computers are being used increasingly. In this paper the possibility of using a simple multicomputer system as a parallel computer is investigated. Paral...

Explicit hermitian methods, which have smaller truncation errors and better stability properties than presently available explicit methods, are derived for the one-dimensional nonhomogeneous parabolic differential equation. As these hermitian methods are not defined for all internal points of the difference grid used, smoothing methods which enable...

Explicit difference methods employing a smoothing technique for the numerical solution of the heat equation are adapted to the solution of a system of two coupled second-order differential equations. The practical application of these methods is investigated by using them to solve the, fourth-order parabolic equation describing the vibrations of a...

An explicit difference approximation of the one-dimensional diffusion equation equation, which is stable for any choice of the difference gird and has a comparatively small truncation error, is described. A smoothing formula, which makes the practical use of this method possible, is given.Zuerst wird ein explizites Differenzenverfahren beschrieben,...

Summary Considering the one-dimensional diffusion equation, smoothing formulas are constructed which, when applied to solutions computed by use of unstable explicit difference approximations, result in stable approximation procedures. It is then shown that more general difference approximations can be written as combinations of simpler difference e...

It is shown that the well-known Du Fort-Frankel difference approximation of the one-dimensional diffusion equation is a special case of a more general difference equation, which is also stable for any choice of the difference grid. Results computed with the aid of a smoothing formula, are given.Dieser Artikel zeigt, da das bekannte Du Fort-Frankel...

The lectures in this book were supposed to be concerned with the following topics that were shaping the different sections: numerical algorithms; non-numerical algorithms; particular areas of applications of parallel computing; programming, programming languages and operating systems; and structure of existing and future parallel computers includin...

Thesis (PhD)--University of Cape Town, 1969.