Embedding object-oriented design in system engineering

The Unified Modeling Language (UML) is a collection of techniques intended to document design decisions about software. This contrasts with systems engineering approaches such as for exampleStatemate and the Yourdon Systems Method (YSM), in which the design of an entire system consisting of software and hardware can be documented. The difference between the system- and the software level is reflected in differences between execution semantics as well as in methodology. In this paper, I show how the UML can be used as a system-level design technique. I give a conceptual framework for engineering design that accommodates the system- as well as the software level and show how techniques from the UML and YSM can be classified within this framework, and how this allows a coherent use of these techniques in a system engineering approach. These ideas are illustrated by a case study in which software for a compact dynamic bus station is designed. Finally, I discuss the consequences of this approach for a semantics of UML constructs that would be appropriate for system-level design

Towards a methodology for rigorous development of generic requirements patterns

We present work in progress on a methodology for the engineering, validation and verification of generic requirements using domain engineering and formal methods. The need to develop a generic requirement set for subsequent system instantiation is complicated by the addition of the high levels of verification demanded by safety-critical domains such as avionics. We consider the failure detection and management function for engine control systems as an application domain where product line engineering is useful. The methodology produces a generic requirement set in our, UML based, formal notation, UML-B. The formal verification both of the generic requirement set, and of a particular application, is achieved via translation to the formal specification language, B, using our U2B and ProB tools

A methodological proposal and tool support for the HL7 standards compliance in the development of health information systems

Health information systems are increasingly complex, and their development is presented as a challenge for software development companies offering quality, maintainable and interoperable products. HL7 (Health level 7) International, an international non-profit organization, defines and maintains standards related to health information systems. However, the modelling languages proposed by HL7 are far removed from standard languages and widely known by software engineers. In these lines, NDT is a software development methodology that has a support tool called NDT-Suite and is based, on the one hand, on the paradigm of model-driven engineering and, on the other hand, in UML that is a widely recognized standard language. This paper proposes an extension of the NDT methodology called MoDHE (Model Driven Health Engineering) to offer software engineers a methodology capable of modelling health information systems conforming to HL7 using UML domain models

Collaborative Verification-Driven Engineering of Hybrid Systems

Hybrid systems with both discrete and continuous dynamics are an important model for real-world cyber-physical systems. The key challenge is to ensure their correct functioning w.r.t. safety requirements. Promising techniques to ensure safety seem to be model-driven engineering to develop hybrid systems in a well-defined and traceable manner, and formal verification to prove their correctness. Their combination forms the vision of verification-driven engineering. Often, hybrid systems are rather complex in that they require expertise from many domains (e.g., robotics, control systems, computer science, software engineering, and mechanical engineering). Moreover, despite the remarkable progress in automating formal verification of hybrid systems, the construction of proofs of complex systems often requires nontrivial human guidance, since hybrid systems verification tools solve undecidable problems. It is, thus, not uncommon for development and verification teams to consist of many players with diverse expertise. This paper introduces a verification-driven engineering toolset that extends our previous work on hybrid and arithmetic verification with tools for (i) graphical (UML) and textual modeling of hybrid systems, (ii) exchanging and comparing models and proofs, and (iii) managing verification tasks. This toolset makes it easier to tackle large-scale verification tasks

An Analysis and New Methodology for Reverse Engineering of UML Behavioral

The emergence of Unified Modeling Language (UML) as a standard for modeling systems has encouraged the use of automated software tools that facilitate the development process from analysis through coding. Reverse Engineering has become a viable method to measure an existing system and reconstruct the necessary model from its original. The Reverse Engineering of behavioral models consists in extracting high-level models that help understand the behavior of existing software systems. In this paper we present an ongoing work on extracting UML diagrams from object-oriented programming languages. we propose an approach for the reverse engineering of UML behavior from the analysis of execution traces produced dynamically by an object-oriented application using formal and semi-formal techniques for modeling the dynamic behavior of a system. Our methods show that this approach can produce UML behavioral diagrams in reasonable time and suggest that these diagrams are helpful in understanding the behavior of the underlying application

Towards a method for rigorous development of generic requirements patterns

We present work in progress on a method for the engineering, validation and verification of generic requirements using domain engineering and formal methods. The need to develop a generic requirement set for subsequent system instantiation is complicated by the addition of the high levels of verification demanded by safety-critical domains such as avionics. Our chosen application domain is the failure detection and management function for engine control systems: here generic requirements drive a software product line of target systems. A pilot formal specification and design exercise is undertaken on a small (twosensor) system element. This exercise has a number of aims: to support the domain analysis, to gain a view of appropriate design abstractions, for a B novice to gain experience in the B method and tools, and to evaluate the usability and utility of that method.We also present a prototype method for the production and verification of a generic requirement set in our UML-based formal notation, UML-B, and tooling developed in support. The formal verification both of the structural generic requirement set, and of a particular application, is achieved via translation to the formal specification language, B, using our U2B and ProB tools

Use of UML 2.1 to model multi-agent systems based on a goal-driven software engineering ontology

In this paper, we present the use of UML 2.1 to model multi-agent systems based on a goal-driven software engineering ontology. The lack of an efficient standardized modeling language is evident. The uses of UML and stereotypes UML to model multi-agent systems have been proposed. However, there are still a number of issues with the existing approaches due to inconsistent semantics of the existing UML diagrams and unintuitive and complext notations. UML 2.1 allows representing more complex scenarios and introducing greater details into the modeling process enabling effective capture and representation of multi-agent actions and interactions. UML 2.1 has not only enabled the introduction of a notation for the Ontology based multi-agent systems, but also effective capture and representation of the dynamic processes associated with these Ontology based multi-agent systems

The Impact of Petri Nets on System-of-Systems Engineering

The successful engineering of a large-scale system-of-systems project towards deterministic behaviour depends on integrating autonomous components using international communications standards in accordance with dynamic requirements. To-date, their engineering has been unsuccessful: no combination of top-down and bottom-up engineering perspectives is adopted, and information exchange protocol and interfaces between components are not being precisely specified. Various approaches such as modelling, and architecture frameworks make positive contributions to system-of-systems specification but their successful implementation is still a problem. One of the most popular modelling notations available for specifying systems, UML, is intuitive and graphical but also ambiguous and imprecise. Supplying a range of diagrams to represent a system under development, UML lacks simulation and exhaustive verification capability. This shortfall in UML has received little attention in the context of system-of-systems and there are two major research issues: 1. Where the dynamic, behavioural diagrams of UML can and cannot be used to model and analyse system-of-systems 2. Determining how Petri nets can be used to improve the specification and analysis of the dynamic model of a system-of-systems specified using UML This thesis presents the strengths and weaknesses of Petri nets in relation to the specification of system-of-systems and shows how Petri net models can be used instead of conventional UML Activity Diagrams. The model of the system-of-systems can then be analysed and verified using Petri net theory. The Petri net formalism of behaviour is demonstrated using two case studies from the military domain. The first case study uses Petri nets to specify and analyse a close air support mission. This case study concludes by indicating the strengths, weaknesses, and shortfalls of the proposed formalism in system-of-systems specification. The second case study considers specification of a military exchange network parameters problem and the results are compared with the strengths and weaknesses identified in the first case study. Finally, the results of the research are formulated in the form of a Petri net enhancement to UML (mapping existing activity diagram elements to Petri net elements) to meet the needs of system-of-systems specification, verification and validation

The engineering of generic requirements for failure management

We consider the failure detection and management function for engine control systems as an application domain where product line engineering is indicated. The need to develop a generic requirement set - for subsequent system instantiation - is complicated by the addition of the high levels of verification demanded by this safety-critical domain, subject to avionics industry standards. We present our case study experience in this area as a candidate methodology for the engineering, validation and verification of generic requirements using domain engineering and Formal Methods techniques and tools. For a defined class of systems, the case study produces a generic requirement set in UML and an example instantiation in tabular form. Domain analysis and engineering produce a model which is integrated with the formal specification/ verification method B by the use of our UML-B profile. The formal verification both of the generic requirement set, and of a simple system instance, is demonstrated using our U2B and ProB tools. This work is a demonstrator for a tool-supported method which will be an output of EU project RODIN. The method, based in the dominant UML standard, will exploit formal verification technology largely as a "black box" for this novel combination of product line, failure management and safety-critical engineering

REM4j - A framework for measuring the reverse engineering capability of UML CASE tools

Reverse Engineering is becoming increasingly important in the software development world today as many organizations are battling to understand and maintain old legacy systems. Today’s software engineers have inherited these legacy systems which they may know little about yet have to maintain, extend and improve. Currently there is no framework or strategy that an organisation can use to determine which UML CASE tool to use. This paper sets down such a framework, to allow organisations to base their tool choice on this reliable framework. We present the REM4j tool, an automated tool, for benchmarking UML CASE tools, we then use REM4j to carry out one such evaluation with eleven UML CASE tools. This framework allows us to reach a conclusion as to which is the most accurate and reliable UML CASE tool