Philipp Reinkemeier

Bio: Philipp Reinkemeier is an academic researcher from OFFIS. The author has contributed to research in topics: Component-based software engineering & Systems design. The author has an hindex of 8, co-authored 16 publications receiving 369 citations.

Contracts for System Design

Abstract: Recently, contract-based design has been proposed as an “orthogonal” approach that complements system design methodologies proposed so far to cope with the complexity of system design. Contract-based design provides a rigorous scaffolding for verification, analysis, abstraction/refinement, and even synthesis. A number of results have been obtained in this domain but a unified treatment of the topic that can help put contract-based design in perspective was missing. This monograph intends to provide such a treatment where contracts are precisely defined and characterized so that they can be used in design methodologies with no ambiguity. In particular, this monograph identifies the essence of complex system design using contracts through a mathematical “meta-theory”, where all the properties of the methodology are derived from a very abstract and generic notion of contract. We show that the meta-theory provides deep and illuminating links with existing contract and interface theories, as well as guidelines for designing new theories. Our study encompasses contracts for both software and systems, with emphasis on the latter. We illustrate the use of contracts with two examples: requirement engineering for a parking garage management, and the development of contracts for timing and scheduling in the context of the AUTOSAR methodology in use in the automotive sector.

Contracts for Systems Design: Theory

Abstract: Aircrafts, trains, cars, plants, distributed telecommunication military or health care systems, and more, involve systems design as a critical step. Complexity has caused system design times and costs to go severely over budget so as to threaten the health of entire industrial sectors. Heuristic methods and standard practices do not seem to scale with complexity so that novel design methods and tools based on a strong theoretical foundation are sorely needed. Model-based design as well as other methodologies such as layered and compositional design have been used recently but a unified intellectual framework with a complete design flow supported by formal tools is still lacking. Recently an “orthogonal” approach has been proposed that can be applied to all methodologies introduced thus far to provide a rigorous scaffolding for verification, analysis and abstraction/refinement: contractbased design. Several results have been obtained in this domain but a unified treatment of the topic that can help in putting contract-based design in perspective is missing. This paper intends to provide such treatment where contracts are precisely defined and characterized so that they can be used in design methodologies such as the ones mentioned above with no ambiguity. In addition, the paper provides an important link between interface and contract theories to show similarities and correspondences. This paper is complemented by a companion paper where contract based design is illustrated through use cases.

A pattern-based requirement specification language: Mapping automotive specific timing requirements.

Abstract: Today most requirement specifications are documents written in natural language. Natural language however is abiguous. Thus computer-aided verification of system-models against such requirement specifications is generally impossible. In this paper we propose a textual requirement specification language (RSL), that is based on patterns, which have a formally defined semantics. RSL is able to express requirements from multiple aspects (e.g. real-time, safety, etc.) on a system. In order to apply RSL in the domain of automotive systems, it has to support timing requirements as the Timing Augmented Description Language (TADL). TADL is the comming standard for handling timing information in the automotive domain. In this paper, we present a mapping of TADL constraints to RSL patterns.

A model-based design methodology with contracts to enhance the development process of safety-critical systems

Abstract: In this paper a new methodology to support the development process of safety-critical systems with contracts is described. The meta-model of Heterogeneous Rich Component (HRC) is extended to a Common System Meta-Model (CSM) that benefits from the semantic foundation of HRC and provides analysis techniques such as compatibility checks or refinement analyses. The idea of viewpoints, perspectives, and abstraction levels is discussed in detail to point out how the CSM supports separation of concerns. An example is presented to detail the transition concepts between models. From the example we conclude that our approach proves valuable and supports the development process.

Real-time scheduling interfaces and contracts for the design of distributed embedded systems

Abstract: A notion of interfaces based on regular languages for modelling and verification of real-time scheduling constraints was proposed in [5] This initial notion considers task sets running on single resources, and simple deadline requirements We extend the approach to enable support for complex task models running on systems with multiple resources We show that this extension preserves all properties of the original notion In addition, this extension gives rise to the application of our interfaces in the design of more complex systems, where components can be spread over distributed architectures The work is complemented by an initial implementation that performs scheduling analysis for a relevant class of real-time interfaces It actually constructs an interface for a system model if it satisfies a set of given real-time requirements

Model Driven Engineering

Abstract: The Object Management Group's (OMG) Model Driven Architecture (MDA) strategy envisages a world where models play a more direct role in software production, being amenable to manipulation and transformation by machine. Model Driven Engineering (MDE) is wider in scope than MDA. MDE combines process and analysis with architecture. This article sets out a framework for model driven engineering, which can be used as a point of reference for activity in this area. It proposes an organisation of the modelling 'space' and how to locate models in that space. It discusses different kinds of mappings between models. It explains why process and architecture are tightly connected. It discusses the importance and nature of tools. It identifies the need for defining families of languages and transformations, and for developing techniques for generating/configuring tools from such definitions. It concludes with a call to align metamodelling with formal language engineering techniques.

Real-Time Systems

Abstract: From the Publisher: Real-Time Systems is both a valuable reference for professionals and an advanced text for Computer Science and Computer Engineering students. Real world real-time applications based on research and practice State-of-the-art algorithms and methods for validation Methods for end-to-end scheduling and resource management More than 100 illustrations to enhance understanding Comprehensive treatment of the technology known as RMA (rate-monotonic analysis) methods A supplemental Companion Website www.prenhall.com/liu

Contracts for System Design

Abstract: Recently, contract-based design has been proposed as an “orthogonal” approach that complements system design methodologies proposed so far to cope with the complexity of system design. Contract-based design provides a rigorous scaffolding for verification, analysis, abstraction/refinement, and even synthesis. A number of results have been obtained in this domain but a unified treatment of the topic that can help put contract-based design in perspective was missing. This monograph intends to provide such a treatment where contracts are precisely defined and characterized so that they can be used in design methodologies with no ambiguity. In particular, this monograph identifies the essence of complex system design using contracts through a mathematical “meta-theory”, where all the properties of the methodology are derived from a very abstract and generic notion of contract. We show that the meta-theory provides deep and illuminating links with existing contract and interface theories, as well as guidelines for designing new theories. Our study encompasses contracts for both software and systems, with emphasis on the latter. We illustrate the use of contracts with two examples: requirement engineering for a parking garage management, and the development of contracts for timing and scheduling in the context of the AUTOSAR methodology in use in the automotive sector.

A Contract-Based Methodology for Aircraft Electric Power System Design

Abstract: In an aircraft electric power system, one or more supervisory control units actuate a set of electromechanical switches to dynamically distribute power from generators to loads, while satisfying safety, reliability, and real-time performance requirements. To reduce expensive redesign steps, this control problem is generally addressed by minor incremental changes on top of consolidated solutions. A more systematic approach is hindered by a lack of rigorous design methodologies that allow estimating the impact of earlier design decisions on the final implementation. To achieve an optimal implementation that satisfies a set of requirements, we propose a platform-based methodology for electric power system design, which enables independent implementation of system topology (i.e., interconnection among elements) and control protocol by using a compositional approach. In our flow, design space exploration is carried out as a sequence of refinement steps from the initial specification toward a final implementation by mapping higher level behavioral and performance models into a set of either existing or virtual library components at the lower level of abstraction. Specifications are first expressed using the formalisms of linear temporal logic, signal temporal logic, and arithmetic constraints on Boolean variables. To reason about different requirements, we use specialized analysis and synthesis frameworks and formulate assume guarantee contracts at the articulation points in the design flow. We show the effectiveness of our approach on a proof-of-concept electric power system design.