Predrag Filipovikj

Reassessing the Pattern-Based Approach for Formalizing Requirements in the Automotive Domain

The importance of using formal methods and techniques for verification of requirements in the automotive industry has been greatly emphasized with the introduction of the new ISO26262 standard for road vehicles functional safety. The lack of support for formal modeling of requirements still represents an obstacle for the adoption of the formal methods in industry. This paper presents a case study that has been conducted in order to evaluate the difficulties inherent to the process of transforming the system requirements from their traditional written form into semi-formal notation. The case study focuses on a set of non-structured functional requirements for the Electrical and Electronic (E/E) systems inside heavy road vehicles, written in natural language, and reassesses the applicability of the extended Specification Pattern System (SPS) represented in a restricted English grammar. Correlating this experience with former studies, we observe that, as previously claimed, the concept of patterns is likely to be generally applicable for the automotive domain. Additionally, we have identified some potential difficulties in the transformation process, which were not reported by the previous studies and will be used as a basis for further research.

Ten tips to succeed in global software engineering education: What do the students say?

When a project had followed advices from the best practices, we can raise a question whether the success (or failure) of the project came from following (or not following) the best practices, or whether there were additional reasons that led to the positive (or negative) outcome. In this paper we analyze a case of a student project performed as a part of our Distributed Software Development course. The project followed the advices from the “Ten Tips to Succeed in Global Software Engineering Education” publication. This paper analyzes the project work with respect to the advices. Focusing on the perspective of a student participating in the project, the paper tries to answer whether following the advices is sufficient for a positive project outcome.

Simulink to UPPAAL Statistical Model Checker: Analyzing Automotive Industrial Systems

The advanced technology used for developing modern automotive systems increases their complexity, making their correctness assurance very tedious. To enable analysis by simulation, but also enhance understanding and communication, engineers use MATLAB/Simulink modeling during system development. In this paper, we provide further analysis means to industrial Simulink models by proposing a pattern-based, execution-order preserving transformation of Simulink blocks into the input language of UPPAAL Statistical Model checker, that is, timed (or hybrid) automata with stochastic semantics. The approach leads to being able to analyze complex Simulink models of automotive systems, and we report our experience with two vehicular systems, the Brake-by-Wire and the Adjustable Speed Limiter.

Integrating Pattern-Based Formal Requirements Specification in an Industrial Tool-Chain

The lack of formal system specifications is a major obstacle to the widespread adoption of formal verification techniques in industrial settings. Specification patterns represent a promising approach that can fill this gap by enabling non-expert practitioners to write formal specifications based on reusing solutions to commonly occurring problems. Despite the fact that the specification patterns have been proven suitable for specification of industrial systems, there is no engineer-friendly tool support adequate for industrial adoption. In this paper, we present a tool called SESAMM Specifier in which we integrate a subset of the specification patterns for formal requirements specification, called SPS, into an existing industrial tool-chain. The tool provides the necessary means for the formal specification of system requirements and the later validation of the formally expressed behavior.

SMT-based consistency analysis of industrial systems requirements

As the complexity of industrial systems increases, it becomes difficult to ensure the correctness of system requirements specifications with respect to certain criteria such as consistency. Automated techniques for consistency checking of requirements, mostly by means of model checking, have been proposed in academia. However, such approaches can sometimes be costly in terms of modeling and analysis time or not applicable for certain types of properties. In this paper, we present a complementary method that relies on pattern-based formalization of requirements and automated consistency checking using the state-of-the-art SMT tool Z3. For validation, we apply our method on a set of timed computation tree logic requirements of an industrial automotive subsystem called the Fuel Level Display.

Automated SMT-based consistency checking of industrial critical requirements

With the ever-increasing size, complexity and intricacy of system requirements specifications, it becomes difficult to ensure their correctness with respect to certain criteria such as consistency. Automated formal techniques for consistency checking of requirements, mostly by means of model checking, have been proposed in academia. Sometimes such techniques incur a high modeling cost or analysis time, or are not applicable. To address such problems, in this paper we propose an automated consistency analysis technique of requirements that are formalized based on patterns, and checked using state-of-the-art Satisfiability Modulo Theories solvers. Our method assumes several transformation steps, from textual requirements to formal logic, and next into the format suited for the SMT tool. To automate such steps, we propose a tool, called PROPAS, that does not require any user intervention during the transformation and analysis phases, thus making the consistency analysis usable by non-expert practitioners. For validation, we apply our method on a set of timed computation tree logic requirements of an industrial automotive system called the Fuel Level Display.