No description available.

No description available.

This diploma thesis deals with computer simulation. In the opening, there are descriptions of theoretical aspect of computer simulation, simulation model structure and individual phases of simulation process. After that follow areas of application, characteristic features of each area and classification of simulation models, that are used in those areas. In this thesis only 4 areas of application were chosen: automotive industry, logistics and transportation systems, healthcare and military simulation. Each application area contains descriptions of a few chosen simulation software products that are used in this area. At the close there is a price comparison of described simulation products, their usage in Czech Republic and their development evaluation.

Zugl.: Cottbus, Techn. Universiẗat, Diss., 2008.

No description available.

No description available.

CFD-Analysen sind in den letzten Jahren ein fester Bestandteil in der Produktentwicklung geworden. Dies liegt primär daran, dass es in den letzten Jahrzehnten große Fortschritte in der Entwicklung der Software und dem Preisverfall der Hardware gegeben hat. Das einstige Expertenwerkzeug CFD hat heutzutage auch in vielen kleinen und mittelständischen Unternehmen seinen festen Platz gefunden und somit ein enormes Anwendungsspektrum erschlossen. Ein wesentlicher Schlüssel für diesen Erfolg war und ist die Effizienz bei der Erstellung der Berechnungsmodelle. Ein Meilenstein war die ab Mitte der 1990er Jahre verfügbare Verwendung unstrukturierter Netze. Erst durch den Einsatz von Tetraedern konnten beliebig komplexe Strukturen überhaupt vernetzt werden. Dieser Vortrag beschreibt die Verwendung von sogenannten kartesischen Netzen in Kombination mit der Immersed Boundary Methode. Dabei handelt es sich um einen bislang wenig beachteten Weg, der den Anwender nochmals erheblich bei der Modellaufbereitung entlastet und somit auch anspruchsvolle CFD-und Thermalsimulationen für Konstrukteure zugänglich macht.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.

“Hardware in the Loop” (HIL) testing is widely used in the automotive industry. The sophisticated electronic control units used for vehicle control are usually tested and evaluated using HIL-simulations. The HIL increases the degree of realistic testing of any system. Moreover, it helps in designing the structure and control of the system under test so that it works effectively in the situations that will be encountered in the system. Due to the size and the complexity of interaction within a power network, most research is based on pure simulation. To validate the performance of physical generator or protection system, most testing is constrained to very simple power network. This research, however, examines a method to test power system hardware within a complex virtual environment using the concept of the HIL. The HIL testing for electronic control units and power systems protection device can be easily performed at signal level. But performance of power systems equipments, such as distributed generation systems can not be evaluated at signal level using HIL testing. The HIL testing for power systems equipments is termed here as ‘Power Network in the Loop’ (PNIL). PNIL testing can only be performed at power level and requires a power amplifier that can amplify the simulation signal to the power level. A power network is divided in two parts. One part represents the Power Network Under Test (PNUT) and the other part represents the rest of the complex network. The complex network is simulated in real time simulator (RTS) while the PNUT is connected to the Voltage Source Converter (VSC) based power amplifier. Two way interaction between the simulator and amplifier is performed using analog to digital (A/D) and digital to analog (D/A) converters. The power amplifier amplifies the current or voltage signal of simulator to the power level and establishes the power level interaction between RTS and PNUT. In the first part of this thesis, design and control of a VSC based power amplifier that can amplify a broadband voltage signal is presented. A new Hybrid Discontinuous Control method is proposed for the amplifier. This amplifier can be used for several power systems applications. In the first part of the thesis, use of this amplifier in DSTATCOM and UPS applications are presented. In the later part of this thesis the solution of network in the loop testing with the help of this amplifier is reported. The experimental setup for PNIL testing is built in the laboratory of Queensland University of Technology and the feasibility of PNIL testing has been evaluated using the experimental studies. In the last section of this thesis a universal load with power regenerative capability is designed. This universal load is used to test the DG system using PNIL concepts. This thesis is composed of published/submitted papers that form the chapters in this dissertation. Each paper has been published or submitted during the period of candidature. Chapter 1 integrates all the papers to provide a coherent view of wide bandwidth switching amplifier and its used in different power systems applications specially for the solution of power systems testing using PNIL.

Cette thèse s’intéresse aux effets des attaques par fautes physiques sur le code d’un système embarqué en particulier la carte à puce. De telles attaques peuvent compromettre la sécurité du système en donnant accès à des informations confidentielles, en compromettant l’intégrité de données sensibles ou en perturbant le fonctionnement pendant l’exécution. Dans cette thèse, nous décrivons des propriétés de sécurité permettant d’exprimer les garanties du système et établissons un modèle d’attaque de haut niveau définissant les capacités d’un attaquant à modifier le système. Ces propriétés et ce modèle nous servent à vérifier la sécurité du code par analyse statique ou test dynamique, combinés avec l’injection d’attaques, simulant les conséquences logicielles des fautes physiques. Deux méthodologies sont ainsi développées afin de vérifier le comportement fonctionnel du code sous attaques, tester le fonctionnement des sécurités implémentées et identifier de nouvelles attaques. Ces méthodologies ont été mises en oeuvre dans un cadre industriel afin de faciliter le travail du développeur chargé de sécuriser un code de carte à puce. / This thesis focuses on the effects of attacks by physical faults on embedded source code specifically for smart cards. Such attacks can compromise the security of the system by providing access to confidential information, compromising the integrity of sensitive data or disrupting the execution flow. In this thesis, we describe security properties to express security guarantees on the system. We also offer an attack model defining at high level an attacker’s ability to disrupt the system. With these properties and model, we check the source code security against physical attacks. We use static analysis and dynamic testing, combined with attack injection to simulate the consequences of physical faults at software level. Two techniques are created to stress the functional behavior of the code under attack, test the reliability of built-in security countermeasures and identify new threats. These techniques were implemented in a framework to help developers secure their source code in an industrial environment.