Validation of formal specifications

Colloque avec actes sans comité de lecture.TLA, (the Temporal Logic of Actions) is a linear temporal logic for specifying and reasoning about reactive systems. The purpose of this paper is to develop an animator and a model checker, both based on a subset of TLA, and illustrates how we can combine these tools to validate TLA specifications

POTS: An OO LOTOS Specification

Rapport interne.La spécification et validation du POTS (plain old telephone service) en utilisant LOTOS (language of temporal ordering specification). l'approche orienté objet est examiné

Animating formal specifications : a telephone simulation case study

Colloque avec actes sans comité de lecture.We believe that a more rigorous method of specification and validation can be achieved by first developing a {\it specification architecture} whose high-level semantics are based on object oriented concepts. This architecture promotes the construction of new functionality in a formal manner using rigorous notions of composition and inheritance. An object oriented approach will also facilitate incremental approaches to validation and verification. We present our first steps towards producing such an architecture for the Plain Old Telephone Service (POTS), which is specified and validated using a formal object oriented language based on LOTOS. The method by which the formal model is derived from the informal understanding of the requirements is examined. Validation based on meta-analysis of the problem structure is elucidated

Isotopic Characteristics and Water Interaction of Ifni Lake and Spring of Tifnoute Valley (High Atlas Mountains, Morocco, North of Africa)

Geochemical and isotopic investigations were carried out to indicate the interaction process between Ifni Lake water and high valley of Tifnoute springs. A total of 18 water samples were collected and analyzed. The Ifni Lake constitutes a veritable water resource in the study area, and this water can be the origin of alimentation the springs located in the high valley the Tifnoute. This study aims to improve the interaction between Ifni Lake water and the springs of high valley of Tifnoute. It is mainly focused to identify the origin of groundwater recharge and mineralization. The environmental isotope (deuterium (δ2H) and oxygen-18 (δ18O)) measurements allowed understanding the hydro geochemical process, the origin of the mineralization of the water. Also the results identify the relationship between the waters of Ifni Lake and the spring's water of high valley of Tifnoute. The isotopic compositions reveal that the origin of Ifni Lake water is meteoric, and the water infiltrates directly in the groundwater without any evaporation

NuMDG: A New Tool for Multiway Decision Graphs Construction

Multiway Decision Graphs (MDGs) are a canonical representation of a subset of many-sorted first-order logic. This subset generalizes the logic of equality with abstract types and uninterpreted function symbols. The distinction between abstract and concrete sorts mirrors the hardware distinction between data path and control. Here we consider ways to improve MDGs construction. Efficiency is achieved through the use of the Generalized-If-Then-Else (GITE) commonly operator in Binary Decision Diagram packages. Consequently, we review the main algorithms used for MDGs verification techniques. In particular, Relational Product and Pruning by Subsumption are algorithms defined uniformly through this single GITE operator which will lead to a more efficient implementation. Moreover, we provide their correctness proof. This work can be viewed as a way to accommodate the ROBBD algorithms to the realm of abstract sorts and uninterpreted functions. The new tool, called NuMDG, accepts an extended SMV language, supporting abstract data sorts. Finally, we present experimental results demonstrating the efficiency of the NuMDG tool and evaluating its performance using a set of benchmarks from the SMV package

The invoice system problem in TLA+

Colloque avec actes et comité de lecture.In this paper, we address the case study proposed by Habrias- namely specifying an Invoice System. Our specifications are written in TLA+, a formal specification language based on TLA (the Temporal Logic of Actions). We describe an animation language that allows us to validate our specifications. Finally, the specification, the validation and the verification of the invoice system are illustrated

Animating TLA Specifications

Colloque avec actes et comité de lecture.TLA (the Temporal Logic of Actions) is a linear temporal logic for specifying and reasoning about reactive systems. We define a subset of TLA whose formulas are amenable to validation by animation, with the intent to facilitate the communication between domain and solution experts in the design of reactive systems