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Mathematical modelling of single spillways is well documented in literature. For parallel spillways however, there is a lack of documented, verified, and validated cases. Here, in this article, ANSYS-CFX is used to simulate the flow over three parallel ogee-crested spillways. For mesh size verification, a grid convergence study is performed by Richardson extrapolation. The turbulence model chosen for this simulation is the k-ε model and the volume of fluid method is used to simulate the water-air interface. This article details the models ability to accurately predict flow distribution at the spillways, and the water levels. The mesh is kept relatively coarse at the channel inlet with increased mesh density at the spillways. The results are validated against experimental data from Vattenfall AB, R&Ds laboratories. The geometry and boundary conditions of the experiment are tailored for CFD. The flow rate of each spillway is measured separately with high accuracy, and for several different inlet volumetric flows. The simulation results lie within the error estimates of the measuring tools used in the experiments, within ±1%. The volume flow rate differences between the three outlets is very small, within ±1%., ISBN för värdpublikation: 978-1-74272-309-9

Mathematical modelling of single spillways is well documented in literature. For parallel spillways however, there is a lack of documented, verified, and validated cases. Here, in this article, ANSYS-CFX is used to simulate the flow over three parallel ogee-crested spillways. For mesh size verification, a grid convergence study is performed by Richardson extrapolation. The turbulence model chosen for this simulation is the k-ε model and the volume of fluid method is used to simulate the water-air interface. This article details the models ability to accurately predict flow distribution at the spillways, and the water levels. The mesh is kept relatively coarse at the channel inlet with increased mesh density at the spillways. The results are validated against experimental data from Vattenfall AB, R&Ds laboratories. The geometry and boundary conditions of the experiment are tailored for CFD. The flow rate of each spillway is measured separately with high accuracy, and for several different inlet volumetric flows. The simulation results lie within the error estimates of the measuring tools used in the experiments, within ±1%. The volume flow rate differences between the three outlets is very small, within ±1%., ISBN för värdpublikation: 978-1-74272-309-9

Les interfaces graphiques de logiciels modernes requièrent de plus en plus de s’adapter à diverses situations et divers utilisateurs, rendant leur développement plus complexe. Peu de guides et de solutions à faible coût d’intégration dans un projet existent et sont trop souvent dépendants d’une technologie ou d’une plateforme donnée. Ce mémoire présente une technique pour l’implémentation graduelle de comportements adaptatifs dans les interfaces graphiques par le biais de patrons de conception. Les patrons de conception sont des solutions formalisées répondant à des problèmes récurrents, dans ce cas-ci de structuration d’un logiciel pour l’ajout de l’adaptation. Ces derniers sont présentés dans un format normalisé et une implémentation de référence a été développée sous forme de librairie baptisée AdaptivePy. Un prototype démonstratif est utilisé pour comparer une approche d’implémentation ad hoc à celle utilisant la librairie et donc les patrons. Les gains observés sont au niveau de la séparation des préoccupations, de la cohésion des méthodes, de la localisation des changements pour l’ajout de l’adaptation et de l’extensibilité. Aussi, ce mémoire présente des métriques visant la vérification de l’organisation des composants d’un logiciel structuré par l’application des patrons de conception. Ces métriques sont des indicateurs de la proportion des situations contextuelles du système que supporte un composant. Les métriques et leur calcul sont présentés dans un format basé sur ce- lui de l’ISO/IEC 25023 et une implémentation de référence a également été développée. Une application typique est évaluée grâce aux métriques et des actions correctives sont présentées pour résoudre les problèmes détectés. L’utilité des métriques pour valider une application développée en utilisant la structure induite par les patrons de conception est ainsi mise en évidence. La méthodologie du projet a suivi un proces

Les interfaces graphiques de logiciels modernes requièrent de plus en plus de s’adapter à diverses situations et divers utilisateurs, rendant leur développement plus complexe. Peu de guides et de solutions à faible coût d’intégration dans un projet existent et sont trop souvent dépendants d’une technologie ou d’une plateforme donnée. Ce mémoire présente une technique pour l’implémentation graduelle de comportements adaptatifs dans les interfaces graphiques par le biais de patrons de conception. Les patrons de conception sont des solutions formalisées répondant à des problèmes récurrents, dans ce cas-ci de structuration d’un logiciel pour l’ajout de l’adaptation. Ces derniers sont présentés dans un format normalisé et une implémentation de référence a été développée sous forme de librairie baptisée AdaptivePy. Un prototype démonstratif est utilisé pour comparer une approche d’implémentation ad hoc à celle utilisant la librairie et donc les patrons. Les gains observés sont au niveau de la séparation des préoccupations, de la cohésion des méthodes, de la localisation des changements pour l’ajout de l’adaptation et de l’extensibilité. Aussi, ce mémoire présente des métriques visant la vérification de l’organisation des composants d’un logiciel structuré par l’application des patrons de conception. Ces métriques sont des indicateurs de la proportion des situations contextuelles du système que supporte un composant. Les métriques et leur calcul sont présentés dans un format basé sur ce- lui de l’ISO/IEC 25023 et une implémentation de référence a également été développée. Une application typique est évaluée grâce aux métriques et des actions correctives sont présentées pour résoudre les problèmes détectés. L’utilité des métriques pour valider une application développée en utilisant la structure induite par les patrons de conception est ainsi mise en évidence. La méthodologie du projet a suivi un proces

This report documents the program and the outcomes of Dagstuhl Seminar 14062 "The Pacemaker Challenge: Developing Certifiable Medical Devices". The aim of the seminar was to bring together leading researchers and industrial partners of this field; the seminary ended up with 24 participants from 8 countries: Canada, Denmark, France, The Unites States, Germany, United Kingdom, Brazil. Through a series of presentations, discussions, and working group meetings, the seminar attempted to get a general view of the field of medical devices and certification issues through the pacemaker challenge. The seminar brought together, on the one hand, researchers from the different notations and various tools. The main outcome of the seminar is the exchange of information between different groups and the project of a book.

This thesis researches the role of software architectural patterns and lightweight formal methods in safety-critical software development. We present a framework that relates the different activities and products from system engineering, safety engineering, system and software requirements, and software architecture explicitly, and demonstrate the proposed framework with a case study involving the architectural design of the software to control the arming device of a fictitious Surface-to-Air Missile. We describe the safety engineering steps for the identification of the system hazards and the critical functions that the software has to provide to avoid premature detonation, resulting in four safety requirements for the software that controls the missile's Electronic Safe Arm Device (ESAD). We formalize the software safety requirements as statechart assertions and validate their correctness via JUnit test. We develop a software architecture for the control software using the Safety Executive pattern, and implement the design in C++ to support a simple time-step simulation to produce the required log files for the automated verification of the design.

[EN] In Model-Driven Development, the main artefacts are conceptual schemas, and efforts are focused on their creation, testing and evolution at different levels of abstraction through transformations. If a conceptual schema has defects, these are passed on to the following stages, including coding. Therefore, techniques for improving the quality of conceptual schemas must be implemented to assure the correct generation of final software products. One of the challenges in Model-Driven Development is being able to identify defects early on, at the level of conceptual schemas, as this would help reduce development costs and improve software quality. In this research proposal we suggest an approach for testing-based conceptual schema validation in order to improve quality.

In Model-Driven Development, the main artefacts are conceptual schemas, and efforts are focused on their creation, testing and evolution at different levels of abstraction through transformations. If a conceptual schema has defects, these are passed on to the following stages, including coding. Therefore, techniques for improving the quality of conceptual schemas must be implemented to assure the correct generation of final software products. One of the challenges in Model-Driven Development is being able to identify defects early on, at the level of conceptual schemas, as this would help reduce development costs and improve software quality. In this research proposal we suggest an approach for testing-based conceptual schema validation in order to improve quality.

With the pervasive deployment of software in dependable systems used in everyday life,society is increasingly demanding that software used in critical systems must meet minimum safety, security and reliability standards. Certification is the procedure by which an authorized person or agency assesses and verifies characteristics of a system or product in accordance with established requirements, standards, or regulations. For software, it encompasses traditional notions of verification, but also includes the evidence, tools, methods, and personnel qualifications that are needed to convince the certification authority that the system or product conforms to the relevant standard. Manufacturers of these systems need consistent and effective guidelines as to what constitutes acceptable evidence of software quality, and how to achieve it. Compared to process-oriented certification procedures, recent approaches provide evidence for dependability by the thorough evaluation of the product itself and the adequacy, coverage and maturity of design and quality assurance methods. Substantial progress has been made in areas including safety and assurance cases, the conceptual foundation of evidence and formal methods, and tooling for software design and verification. New approaches are necessary to develop holistic and cost-effective methodologies and to provide integrated tool support for creating certifiable software-intensive systems, as well as product-focused approaches to certifying these systems. Experts from academia and industrial practitioners met in the Dagstuhl Seminar 13051 "Software Certification: Methods and Tools" to discuss and software certification challenges, best practices, and the latest advances in certification technologies in several different software-intensive domains (automotive, aircraft, medical, nuclear, and rail).

Today, a new category of engineering systems is emerging that combines the physical with the computational in a holistic way: Cyber-physical systems (CPS). The key property of these systems is that functionality and salient system properties are emerging from an intensive interaction of physical and computational components. Traditional separation along engineering disciplines in the design of such systems leads to various quality, maintainability and evolutionary problems, and integrated theories and engineering techniques are urgently needed. The purpose of the seminar is to bring together researchers from the field, from both academia and industry to discuss the new scientific foundations and engineering principles for the vastly emerging field of CPS.

Today, embedded software plays a central role in most advanced technical systems such as airplanes, cell phones, and cars, and has become the main driver for innovation. Development, evolution, configuration and maintenance of embedded and distributed software nowadays often are serious challenges as a drastic increase of the software complexity can be observed in practice. The application of model-based engineering technologies to embedded real-time systems seems to be a good candidate to tackle some of the resulting problems.

From 04.11. to 09.11.2007, the Dagstuhl Seminar 07451 ``Model-Based Engineering of Embedded Real-Time Systems'' was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available.

This thesis researches the role of software architectural patterns and lightweight formal methods in safety-critical software development. We present a framework that relates the different activities and products from system engineering, safety engineering, system and software requirements, and software architecture explicitly, and demonstrate the proposed framework with a case study involving the architectural design of the software to control the arming device of a fictitious Surface-to-Air Missile. We describe the safety engineering steps for the identification of the system hazards and the critical functions that the software has to provide to avoid premature detonation, resulting in four safety requirements for the software that controls the missiles Electronic Safe Arm Device (ESAD). We formalize the software safety requirements as statechart assertions and validate their correctness via JUnit test. We develop a software architecture for the control software using the Safety Executive pattern, and implement the design in C++ to support a simple time-step simulation to produce the required log files for the automated verification of the design., http://archive.org/details/applicationofrch1094537646, Lieutenant, Hellenic Navy, Approved for public release; distribution is unlimited.