265154
A Set-Theoretic Model for Real-Time Specification and Reasoning
Timed-trace formalisms have emerged as a powerful method for specifying and reasoning about concurrent real-time systems. We present a simple variant which builds methodically on set theory, and is thus suitable for use by programmers with little formal methods experience.
6469757
Teaching Formal Methods in Context
The Software Engineering Programme at Oxford teaches formal methods as an integral part of its programme of professional education in software engineering. This paper explains how the methods are taught—in the context of emerging trends in software development, and in the context of existing practice—and how their use is promoted through course design and motivating examples.
14174107
Lifting in Z
Formal notations such as Z provide powerful support for writing clear specifications, and for undertaking proofs of properties of those specifications. In this paper, we explore one particular style of specification, with applications in control theory and real-time specification. The notation we define permits the accurate description of concepts in these fields without significant overhead or notational clutter. This notation has long been used by practitioners in these fields; we demonstrate that it may be defined within Draft Standard Z, and that the resulting specifications are amenable to proof.
26464031
A Taxonomy of Web Services Using CSP
Terms such as conversational and stateless are widely used in the taxonomy of web services. We give formal definitions of these terms using the CSP process algebra. Within this framework we also define the notion of Service-Oriented Architecture. These definitions are then used to prove important scalability properties of stateless services. The use of formalism should allow recent debates, concerning how and whether web services provide standardized access to state, to progress more rigorously.
16635941
Packing Steiner trees: a cutting plane algorithm and computational results
In this paper we describe a cutting plane algorithm for the Steiner tree packing problem. We use our algorithm to solve some switchbox routing problems of VLSI-design and report on our computational experience. This includes a brief discussion of separation algorithms, a new LP-based primal heuristic and implementation details. The paper is based on the polyhedral theory for the Steiner tree packing polyhedron developed in our companion paper (this issue) and meant to turn this theory into an algorithmic tool for the solution of practical problems.
34039430
A model of information systems development project performance
. Performance in information systems development (ISD) projects can be critical to business success. But, while project performance has been the subject of much debate, there has been little empirical research into its determinants. A survey of IS projects in the UK and New Zealand is analysed to test hypotheses concerning performance in terms of both project completion and budget (time-cost) variances. Subsequently, a secondary analysis of the findings is used to build a more complete empirical model of project performance. The paper helps to develop the theory of IS development project performance and also has significant implications for practice. Discussion of the findings highlights the importance of project team dynamics, risk management, senior management support for strategic projects and user participation in ensuring successful IS project performance.
14479325
Bus catcher: a context sensitive prototype system for public transportation users
In this paper we describe the architectural andfunctional characteristics of Bus Catcher, a contextsensitive prototype system for public transportation users.Bus Catcher assists mobile users in planning their busrides by providing timely and accurate information aboutcurrent bus locations and estimated arrival times. Acomplete report on the implementation together with apreliminary evaluation of the system is provided in thispaper.
18494896
The steiner tree packing problem in VLSI design
In this paper we describe several versions of the routing problem arising in VLSI design and indicate how the Steiner tree packing problem can be used to model these problems mathematically. We focus on switchbox routing problems and provide integer programming formulations for routing in the knock-knee and in the Manhattan model. We give a brief sketch of cutting plane algorithms that we developed and implemented for these two models. We report on computational experiments using standard test instances. Our codes are able to determine optimum solutions in most cases, and in particular, we can show that some of the instances have no feasible solution if Manhattan routing is used instead of knock-knee routing.
16348358
Agent Chameleons: Virtual Agents Real Intelligence
Agent Chameleons provides virtual agents powered by real intelligence, delivering next generation autonomic entities that can seamlessly migrate, mutate and evolve on their journey between and within physical and digital information spaces.