Predicate Diagrams as Basis for the Verification of Reactive Systems

This thesis proposes a diagram-based formalism for verifying temporal properties of reactive systems. Diagrams integrate deductive and algorithmic verification techniques for the verification of finite and infinite-state systems, thus combining the expressive power and flexibility of deduction with the automation provided by algorithmic methods. Our formal framework for the specification and verification of reactive systems includes the Generalized Temporal Logic of Actions (TLA*) from Merz for both mathematical modeling reactive systems and specifying temporal properties to be verified. As verification method we adopt a class of diagrams, the so-called predicate diagrams from Cansell et al. We show that the concept of predicate diagrams can be used to verify not only discrete systems, but also some more complex classes of reactive systems such as real-time systems and parameterized systems. We define two variants of predicate diagrams, namely timed predicate diagrams and parameterized predicate diagrams, which can be used to verify real-time and parameterized systems. We prove the completeness of predicate diagrams and study an approach for the generation of predicate diagrams. We develop prototype tools that can be used for supporting the generation of diagrams semi-automatically.In dieser Arbeit schlagen wir einen diagramm-basierten Formalismus für die Verifikation reaktiver Systeme vor. Diagramme integrieren die deduktiven und algorithmischen Techniken zur Verifikation endlicher und unendlicher Systeme, dadurch kombinieren sie die Ausdrucksstärke und die Flexibilität von Deduktion mit der von algoritmischen Methoden unterstützten Automatisierung. Unser Ansatz für Spezifikation und Verifikation reaktiver Systeme schließt die Generalized Temporal Logic of Actions (TLA*) von Merz ein, die für die mathematische Modellierung sowohl reaktiver Systeme als auch ihrer Eigenschaften benutzt wird. Als Methode zur Verifikation wenden wir Prädikaten-diagramme von Cansell et al. an. Wir zeigen, daß das Konzept von Prädikatendiagrammen verwendet werden kann, um nicht nur diskrete Systeme zu verifizieren, sondern auch kompliziertere Klassen von reaktiven Systemen wie Realzeitsysteme und parametrisierte Systeme. Wir definieren zwei Varianten von Prädikatendiagrammen, nämlich gezeitete Prädikatendiagramme und parametrisierte Prädikatendiagramme, die benutzt werden können, um die Realzeit- und parametrisierten Systeme zu verifizieren. Die Vollständigkeit der Prädikatendiagramme wird nachgewiesen und ein Ansatz für die Generierung von Prädikatendiagrammen wird studiert. Wir entwickeln prototypische Werkzeuge, die die semi-automatische Generierung von Diagrammen unterstützen

Towards a Mobile Temporal Logic of Actions

I would like to thank my supervisor Fred Kröger. He was willing to discuss at any time, and I could always rely on his full support. I am also thankful to him for his encouragement, especially in some of the rather dragging phases of my work. I am particularly grateful to Stephan Merz. Without his constant support and admirable patience throughout the whole period of writing I probably would not have been able to finish this thesis. I have not only benefited from his extraordinary professional competence, but have also taken advantage of his exceptional human qualities. I also would like to express my gratitude towards Martin Wirsing for providing me with a pleasant working environment by taking me into his group. He always has shown much interest in my work. The idea for the subject of this thesis was initiated by him and Stephan Merz. I feel a need to thank all my friends and my family for not leaving me alone, not even in times when I tended to be almost unbearable... I am aware that I have demanded much of you by asking to share the burden with me. Thank you for no

A Comparative Study of Modern Inference Techniques for Structured Discrete Energy Minimization Problems

International audienceSzeliski et al. published an influential study in 2006 on energy minimization methods for Markov Random Fields (MRF). This study provided valuable insights in choosing the best optimization technique for certain classes of problems. While these insights remain generally useful today, the phenomenal success of random field models means that the kinds of inference problems that have to be solved changed significantly. Specifically , the models today often include higher order interactions, flexible connectivity structures, large label-spaces of different car-dinalities, or learned energy tables. To reflect these changes, we provide a modernized and enlarged study. We present an empirical comparison of more than 27 state-of-the-art optimization techniques on a corpus of 2,453 energy minimization instances from diverse applications in computer vision. To ensure reproducibility, we evaluate all methods in the OpenGM 2 framework and report extensive results regarding runtime and solution quality. Key insights from our study agree with the results of Szeliski et al. for the types of models they studied. However, on new and challenging types of models our findings disagree and suggest that polyhedral methods and integer programming solvers are competitive in terms of runtime and solution quality over a large range of model types

A meta-analysis of previous falls and subsequent fracture risk in cohort studies

NC Harvey acknowledges funding from the UK Medical Research Council (MC_PC_21003; MC_PC_21001). The WHI program is funded by the National Heart, Lung, and Blood Institute, National Institutes of Health, U.S. Department of Health and Human Services through 75N92021D00001, 75N92021D00002, 75N92021D00003, 75N92021D00004, and 75N92021D00005. Funding for the MrOS USA study comes from the National Institute on Aging (NIA), the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), the National Center for Advancing Translational Sciences (NCATS), and NIH Roadmap for Medical Research under the following grant numbers: U01 AG027810, U01 AG042124, U01 AG042139, U01 AG042140, U01 AG042143, U01 AG042145, U01 AG042168, U01 AR066160, and UL1 TR000128. Funding for the SOF study comes from the National Institute on Aging (NIA), and the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), supported by grants (AG05407, AR35582, AG05394, AR35584, and AR35583). Funding for the Health ABC study was from the Intramural research program at the National Institute on Aging under the following contract numbers: NO1-AG-6–2101, NO1-AG-6–2103, and NO1-AG-6–2106.Peer reviewedPostprin

Temporal Logic and State Systems

Temporal logic has developed over the last 30 years into a powerful formal setting for the specification and verification of state-based systems. Based on university lectures given by the authors, this book is a comprehensive, concise, uniform, up-to-date presentation of the theory and applications of linear and branching time temporal logic; TLA (Temporal Logic of Actions); automata-theoretical connections; model checking; and related theories. All theoretical details and numerous application examples are elaborated carefully and with full formal rigor, and the book will serve as a basic source and reference for lecturers, graduate students and researchers

zur Erlangung des akademischen Grades des

tomyfatherVictorino, toLuis. Acknowledgments This work was only possible due to the help of many people. I would like to express my sincere thanks to some of them. My parents initiated me to doubt and reason. My teachers at the university supported me and my inquisitive questions; one who deserves special mention is Jorge “el Profe ” Aguirre, and Ugo Montanari escorted me at my first autonomous steps. Friendsassistedme in different ways, either emotionallyor technically (or both), among them Maribel Fernández, Gudrun Gruber, Andrea and Thom, Daniel Szyld, Max Vogl. Martin Wirsing showed extreme patience to guide me through the jungle of scientific activity. And of course Luis. Part of this work was performed while visiting John Crossley at Monash University. My PhD studywas funded by the DAAD (German Academic Exchange Office).