From Interaction Overview Diagrams to Temporal Logic

In this paper, we use UML Interaction Overview Diagrams as the basis for a user-friendly, intuitive, modeling notation that is well-suited for the design of complex, heterogeneous, embedded systems developed by domain experts with little background on modeling software-based systems. To allow designers to precisely analyze models written with this notation, we provide (part of) it with a formal semantics based on temporal logic, upon which a fully automated, tool supported, verification technique is built. The modeling and verification technique is presented and discussed through the aid of an example system

An Institutional Framework for Heterogeneous Formal Development in UML

We present a framework for formal software development with UML. In contrast to previous approaches that equip UML with a formal semantics, we follow an institution based heterogeneous approach. This can express suitable formal semantics of the different UML diagram types directly, without the need to map everything to one specific formalism (let it be first-order logic or graph grammars). We show how different aspects of the formal development process can be coherently formalised, ranging from requirements over design and Hoare-style conditions on code to the implementation itself. The framework can be used to verify consistency of different UML diagrams both horizontally (e.g., consistency among various requirements) as well as vertically (e.g., correctness of design or implementation w.r.t. the requirements)

Probabilistic UML statecharts for specification and verification: a case study.

This paper introduces a probabilistic extension of UML statecharts. A requirements-level semantics of statecharts is extended to include probabilistic elements. Desired properties for probabilistic statecharts are expressed in the probabilistic logic PCTL, and verified using the model checker Prism. The extension simplifies the verification of critical systems with probabilistic elements, e. g. fault-tolerant systems. The extension is illustrated using a case study: a gambling machine. The theory behind this extension is explained in detail in a paper published recently [JHK02]; this article concentrates on the case study

Telework management and work practices: The case of an Australian telecentre

The contemporary practice of employees working from an alternative location using information and communication technologies to maintain links with the usual workplace, termed telework, creates management and work practice challenges. The case of an Australian public sector organisation's telecentre highlights such issues and the importance of management to telework's success. Despite a range of positive outcomes for employees and their employer, such as a better quality of working life, improved work-life balance and the pioneering of innovative and productive work practices, this experiment in post-Fordist flexibility was ultimately defeated by the lack of leadership skill displayed by an influential senior manager. Copyrigh

An ASM Definition of the Dynamic OCL 2.0 Semantics

The recently adopted OCL 2.0 specification comes with a formal semantics that is based on set theory with a notion of an object model and system states. System states keep the runtime information relevant for the evaluation of OCL expressions. However, not all new language concepts of OCL 2.0 are already addressed in that formal semantics. We show how to overcome this by introducing new components to the object model and system states defining a dynamic semantics of OCL. In order to give precise rules that determine when the current system state has to be updated according to a change in the referred UML model, we make use of adequate mathematical means, namely Abstract State Machines (ASMs). Though our ASM specification also gives a clear definition for the evaluation of OCL constraints, it leaves sufficient flexibility for application specific implementations that have to determine when constraints are to be checked

Towards a Semantics of Activity Diagrams with Semantic Variation Points

Abstract. UML activity diagrams have become an established notation to model control and data flow on various levels of abstraction, ranging from fine-grained descriptions of algorithms to high-level workflow models in business applications. A formal semantics has to capture the flexibility of the interpretation of activity diagrams in real systems, which makes it inappropriate to define a fixed formal semantics. In this paper, we define a semantics with semantic variation points that allow for a customizable, application-specific interpretation of activity diagrams. We examine concrete variants of the activity diagram semantics which may also entail variants of the syntax reflecting the intended use at hand.