Nitsche Type Mortaring for some Elliptic Problem with Corner Singularities

The paper deals with Nitsche type mortaring as a finite element method (FEM) for treating non-matching meshes of triangles at the interface of some domain decomposition. The approach is applied to the Poisson equation with Dirichlet boundary conditions (as a model problem) under the aspect that the interface passes re-entrant corners of the domain. For such problems and non-matching meshes with and without local refinement near the re-entrant corner, some properties of the finite element scheme and error estimates are proved. They show that appropriate mesh grading yields convergence rates as known for the classical FEM in presence of regular solutions. Finally, a numerical example illustrates the approach and the theoretical results. Received July 5, 2001; revised February 5, 2002 Published online April 25, 2002     

SEMPA – Ein Ansatz des Semantischen Prozessmanagements zur Planung von Prozessmodellen

Currently process modeling is mostly done manually. Therefore, the initial design of process models as well as changes to process models which are frequently necessary to react to new market developments or new regulations are time-consuming tasks. In this paper we introduce SEMPA, an approach for the partly automatic planning of process models. Using ontologies to semantically describe actions – as envisioned in Semantic Business Process Management –, a process model for a specified problem setting can be created automatically. In comparison to existing planning algorithms our approach creates process models including control structures and is able to cope with complex and numerical input and output parameters of actions. The prototypical implementation as well as an example taken from the financial services domain illustrate the practical benefit of our approach.     

Remote-Controlled Ambidextrous Robot Hand Concept

In the development of robotic limbs, the side of members is of importance to define the shape of artificial limbs and the range of movements. It is mainly significant tbr biomedical applications concerning patients suffering arms or legs injuries, fn this paper, the concept of an ambidextrous design lbr robot hands is introduced. The fingers can curl in one xvay or another, to imitate either a right hand or a left hand. The advantages and inconveniences of different models have been investigated to optimise the range and the maximum force applied by fingers. Besides, a remote control interthce is integrated to the system, allowing both to send comrnands through internet and to display a video streaming of the ambidextrous hand as feedback. Therefore, a robotic prosthesis could be used for the first time in telerehabilitation. The main application areas targeted are physiotherapy alter strokes or management of phantom pains/br amputees by/earning to control the ambidextrous hand. A client application is also accessible on Facehook social network, making the robotic limb easily reachable for the patients. Additionally the ambidextrous hand can be used tbr robotics research as well as artistic performances.     

Visual Analysis of Trajectories in Multi‐Dimensional State Spaces

Multi‐dimensional data originate from many different sources and are relevant for many applications. One specific sub‐type of such data is continuous trajectory data in multi‐dimensional state spaces of complex systems. We adapt the concept of spatially continuous scatterplots and spatially continuous parallel coordinate plots to such trajectory data, leading to continuous‐time scatterplots and continuous‐time parallel coordinates. Together with a temporal heat map representation, we design coordinated views for visual analysis and interactive exploration. We demonstrate the usefulness of our visualization approach for three case studies that cover examples of complex dynamic systems: cyber‐physical systems consisting of heterogeneous sensors and actuators networks (the collection of time‐dependent sensor network data of an exemplary smart home environment), the dynamics of robot arm movement and motion characteristics of humanoids.     

The process map as an instrument to standardize processes: design and application at a financial service provider

The standardization of processes and the identification of shared business services in a service-oriented architecture (SOA) are currently widely discussed. Above all in practice, however, there still is a lack of appropriate instruments to support these tasks. In this paper an approach for a process map is introduced which allows for a systematic presentation—as complete as possible—of the processes in an enterprise (division). After a consistent refinement of the process has taken place by means of aggregation/disaggregation respectively, generalization/specialization relations, it is possible to identify primarily functional similarities of the detailed sub-processes. The application of the process map at a financial service provider (FSP) highlights how these similarities can be taken as a basis to standardize processes and to identify shared services.     

Technology or methodology? Quantitative historical social research in Germany

Historical social research has developed with the availability of computer technology and has received increasing acceptance with the use of PCs. Methodological standards created by empirical social research are transferred to historical matters. Major contributors are: extension of the factual basis of history, correction of misjudgements, opening of whole groups of mass sources to historical research and bridging the gap between theory and empirical knowledge in the science of history. It complements a philosophical historiography without replacing it. In Germany historical social research has developed outside the traditional university institutes; the Zentrum fur Historische Sozialforschung and Quantum e.V. in Cologne are the major institutions in this context.Heinrich Best (D. Phil.) is a professor of sociology at the University of Cologne. He is director of the Social Science Information Centre (Bonn), director of the scientific advisory board of the Centre for Historical Social Research at his university, and president of the Association for Quantification and Formal Methods in Historical Social Research. Among his publications are Die Männer von Bildung and Besitz (1990) and Computers in the Humanities and Social Sciences (1991).     

Adaptive generation of surfaces in volume data

A widespread approach to generating polygonal approximations of iso-surfaces or contour surfaces in volume data is the socalled marching-cubes algorithm. This algorithm, however, has the disadvantage that the number of polygonal chains generated is considerable. The splitting-box algorithm presented here reduces the number of polygonal chains by adapting their size to the shape of the surface. The resulting polygonal chains offer a wide spectrum for representing the contour surface. An exact representation is achieved by a new type of generic patches calculated from the polygonal chains. Approximations of different quality may be obtained by combining the algorithm generating the patches with simple triangulations.     

Spatially Varying Mixtures Incorporating Line Processes for Image Segmentation

Spatially varying mixture models are characterized by the dependence of their mixing proportions on location (contextual mixing proportions) and they have been widely used in image segmentation. In this work, Gauss-Markov random field (MRF) priors are employed along with spatially varying mixture models to ensure the preservation of region boundaries in image segmentation. To preserve region boundaries, two distinct models for a line process involved in the MRF prior are proposed. The first model considers edge preservation by imposing a Bernoulli prior on the normally distributed local differences of the contextual mixing proportions. It is a discrete line process model whose parameters are computed by variational inference. The second model imposes Gamma prior on the Student’s-t distributed local differences of the contextual mixing proportions. It is a continuous line process whose parameters are also automatically estimated by the Expectation-Maximization (EM) algorithm. The proposed models are numerically evaluated and two important issues in image segmentation by mixture models are also investigated and discussed: the constraints to be imposed on the contextual mixing proportions to be probability vectors and the MRF optimization strategy in the frameworks of the standard and variational EM algorithm.