A Tableaux Calculus for Reducing Proof Size

A tableau calculus is proposed, based on a compressed representation of clauses, where literals sharing a similar shape may be merged. The inferences applied on these literals are fused when possible, which reduces the size of the proof. It is shown that the obtained proof procedure is sound, refutationally complete and allows to reduce the size of the tableau by an exponential factor. The approach is compatible with all usual refinements of tableaux.Comment: Technical Repor

Analysis of SLA compliance in the cloud: An automated, model-based approach

Service Level Agreements (SLA) are commonly used to specify the quality attributes between cloud service providers and the customers. A violation of SLAs can result in high penalties. To allow the analysis of SLA compliance before the services are deployed, we describe in this paper an approach for SLA-aware deployment of services on the cloud, and illustrate its workflow by means of a case study. The approach is based on formal models combined with static analysis tools and generated runtime monitors. As such, it fits well within a methodology combining software development with information technology operations (DevOps)

Fostering Insight into Personal Conceptions of the Elderly: A Simulation Exercise

As a class exercise, Human Development students adopted the roles of elderly individuals by designing costumes to simulate the physical constraints and appearance of advancing age. Then, while engaging in everyday activities, they observed the reactions of themselves and others to their condition and behavior. This activity allowed students to examine their personal conceptions of the elderly. Students reported that the exercise was educational and that it fostered empathy with senior adults

ABS: A core language for abstract behavioral specification

This paper presents ABS, an abstract behavioral specification language for designing executable models of distributed object-oriented systems. The language combines advanced concurrency and synchronization mechanisms for concurrent object groups with a functional language for modeling data. ABS uses asynchronous method calls, interfaces for encapsulation, and cooperative scheduling of method activations inside concurrent objects. This feature combination results in a concurrent object-oriented model which is inherently compositional. We discuss central design issues for ABS and formalize the type system and semantics of Core ABS, a calculus with the main features of ABS. For Core ABS, we prove a subject reduction property which shows that well-typedness is preserved during execution; in particular, "method not understood" errors do not occur at runtime for well-typed ABS models. Finally, we briefly discuss the tool support developed for ABS

Ciencias de la Computación / Computational Sciences Taclets: A New Paradigm for Constructing Interactive Theorem Provers

Abstract. Frameworks for interactive theorem proving give the user explicit control over the construction of proofs based on meta languages that contain dedicated control structures for describing proof construction. Such languages are not easy to master and thus contribute to the already long list of skills required by prospective users of interactive theorem provers. Most users, however, only need a convenient formalism that allows to introduce new rules with minimal overhead. On the the other hand, rules of calculi have not only purely logical content, but contain restrictions on the expected context of rule applications and heuristic information. We suggest a new and minimalist concept for implementing interactive theorem provers called taclet. Their usage can be mastered in a matter of hours, and they are efficiently compiled into the GUI of a prover. We implemented the KeY system, an interactive theorem prover for the full JAVA CARD language based on taclets. Taclets: Un nuevo paradigma para construir demostradores automáticos interactivos Resumen. Los marcos para la demostración interactiva de teoremas permiten al usuario tener control explícito de la construcción de las demostraciones sobre la base de unos metalenguajes que contienen unas estructuras de control dedicadas a la descripción de la construcción de las demostraciones. Estos lenguaje

Intelligent Systems and Formal Methods in Software Engineering

Formal methods in software engineering are an increasingly important application area for intelligent systems. The field has outgrown the area of academic case studies, and industry is showing serious interest. This installment of Trends & Controversies looks at the state of the art in formal methods and discusses the developments that make successful applications possible

Taclets: A New Paradigm for Constructing Interactive Theorem Provers

Abstract. Frameworks for interactive theorem proving give the user explicit control over the construction of proofs based on meta languages that contain dedicated control structures for describing proof construction. Such languages are not easy to master and thus contribute to the already long list of skills required by prospective users of interactive theorem provers. Most users, however, only need a convenient formalism that allows to introduce new rules with minimal overhead. On the the other hand, rules of calculi have not only purely logical content, but contain restrictions on the expected context of rule applications and heuristic information. We suggest a new and minimalist concept for implementing interactive theorem provers called taclet. Their usage can be mastered in a matter of hours, and they are efficiently compiled into the GUI of a prover. We implemented the KeY system, an interactive theorem prover for the full JAVA CARD language based on taclets. Taclets: Un Nuevo Paradigma para construir Demostradores Automáticos Interactivos Resumen. Los marcos para la demostración interactiva de teoremas permiten al usuario tener control explícito de la construcción de las demostraciones sobre la base de unos metalenguajes que contienen unas estructuras de control dedicadas a la descripción de la construcción de las demostraciones. Estos lenguaje