EPM is a prototypical research tool that combines traditional component modeling means with a comprehensive variability management support. In addition to ordinary containment hierarchies of components, the tool provides a few selected system modeling and product management capabilities, e.g. separate modeling of the system's software and hardware architecture and an end-customer / marketing-oriented view on the system's variability. In this article we present EPM and briefly describe its main functionality.

Manufacturer-supplier requirements synchronization, i.e. the systematic and repeated exchange of requirements between manufacturer and supplier, is of high practical relevance but is proving difficult in industrial practice. We motivate the problem and discuss the technical and methodological shortcomings of current practices based on document generation and standardized exchange formats. We then present and discuss a new solution for manufacturer-supplier requirements synchronization based on the use of exchange containers and multi-level requirements systems. The solution is illustrated by an implementation in the tool Rational DOORS using RIF exchange and the DOORS-MuLe extension.

The complexity of embedded automotive systems calls for a more rigorous approach to system development compared to current state of practice. A critical issue is the management of the engineering information that defines the embedded system. Development time, cost efficiency, quality and dependability all benefit from appropriate information management. System modeling based on an architecture description language is a way to keep the engineering information within one information structure. The EAST-ADL was developed in the EAST-EEA project (www.easteea.net) and is an architecture description language for automotive embedded systems. It is currently refined in the ATESSTproject (www.atesst.org). This paper gives an overview of the EAST-ADL and accounts for some recent refinements as developed in the ATESST project. Areas covered include the relation to other standardization initiatives such as UML2.0, AADL, AUTOSAR, SysML, Marte profile, requirements management and variability.

Feature trees are a well-established instrument for domain analysis and modeling. But for highly complex product families like a vehicle manufacturer's product range comprising well-above a thousand technical features - they become very large, and thus cumbersome and inflexible, especially when managing changes to the tree's structure over a long time. Furthermore, a conflict of aims arises when using feature trees in large organizations: while a single global feature tree for the entire company is desirable, local amendments for individual units or projects are indispensable in practice. In this paper, we present a detailed description of this problem and show its great relevance to the automotive domain. We then provide a detailed definition of multi-level feature trees as a possible solution to the above problem. Finally, we describe scenarios how such multi-level feature trees can be put into practice and introduce a prototypical tool implementation of this concept

Feature trees are a well-established instrument for domain analysis and modeling (Czarnecki and Eisenecker, 2000; Kang et al., 1990). But for extremely complex product families like a vehicle manufacturer's product range, they become very large, and thus cumbersome and inflexible. This is particularly true when changes to the tree's structure have to be managed and documented over a long period of time. Furthermore, a conflict of aims arises when using feature trees in large organizations: while a single global feature tree for the entire company is desirable, local amendments are indispensable because often some applications of the feature models require amendments not visible in other application contexts. A research project at DaimlerChrysler, being conducted in cooperation with the Technical University of Berlin, has examined this problem in detail and elaborated an approach based on a distribution of the feature tree definition over several hierarchical levels. Using this approach, amendments to the feature structure can be introduced locally at first, and can later become valid in a broader context, if desired. Currently the approach is being evaluated and refined in case studies.

Requirements engineering has become inescapable for industrial projects. But in every day life, project actors (acquirers, systems engineers, software engineers, information system analysts, domain experts, etc.) are facing multiple constraints: to meet project or company goals (quality, delays, costs), to define and balance requirements from various stakeholders, to use dedicated tools, to create traceability. And one of the key remaining questions is still: how to implement requirements engineering in the most efficient way? Various methods, techniques and tools have been tried out, adopted and optimized, good and bad experiences have been analyzed, know how has been gathered: industry has now developed a number of best requirements engineering practices. But does everyone have the same best practices? Do we need the same approach to elicit requirements, document, negotiate, validate, formalize or trace requirements when you integrate an ERP, when you develop a car, an air traffic control system, an aircraft or a satellite, or when you study the ergonomics of a mobile phone? This paper gathers experienced requirements engineers from various industries, to try learn a few new lessons on the adequacy of various best practices to various industrial sectors.

This paper summarizes problems, solutions and challenges of requirements engineering gained from the development of software-based automotive systems at DaimlerChrysler. The technical domains covered include telematics and entertainment, body electronics and chassis control for both passenger cars and commercial vehicles. Experiences include domain-specific issues, which are related to the different content of requirements in particular application areas and its specific notations, techniques, or process steps, as well as domain-independent issues which are largely independent from requirements content and related to the administration and management of requirements. We argue that the issues presented here, while not necessarily being in the current focus of the requirements engineering research area, are of crucial importance for improving requirements engineering in the development of software for automotive systems, and very likely, to many other kinds of systems as well.

Today, there is a rapidly growing interest to transfer object oriented computing technologies into various fields of control-critical applications. Existing approaches concentrate on abstract design level modeling. We introduce "abstract object systems", an abstract mathematical model of concurrent real time object systems. After that we present a simulation and analysis framework that takes into account implementation issues such as operation processing limits, scheduling strategies, processing priorities and distribution of threads to processors. The usual static class structuring relations are used. Messages exchanged between objects may be either synchronous method calls or asynchronous events. The details of object interaction are controlled by object oriented statecharts. In addition, our framework deals with dynamic creation and deletion of objects and with distribution of threads onto multiple parallel processors.

In this paper, we present an object-oriented approach to the specification of discrete software controllers that are embedded in discrete-continuous (or hybrid) environments.The structure of the controller and its environment is specified using object notations extended to include continuous and hybrid objects.Control behavior is specified with state automata and pre/postconditions using the statechart notation and constructive Z-schemata.The behavior of the environment is specified '\\ith systems of differential equations using an object-oriented extension of Z for the specification of hybrid systems.We use a case study on control of a high-pressure steam boiler to illustrate how the environment structure can help to design the controller and how environment simulation can be used to derive control parameters.

Abstract We present an approach to the literate and structured presentation of formal developments. We discuss the presentation of formal developments in a logical framework and distinguish three aspects: language-related aspects, structural aspects of proofs, and presentational aspects. We illustrate the approach by two examples: a simple mathematical proof of the Knaster-Tarski fixpoint theorem, and a formalization of the VDM development of a revision management system.