A logic-based approach for the verification of UML timed models

This article presents a novel technique to formally verify models of real-time systems captured through a set of heterogeneous UML diagrams. The technique is based on the following key elements: (i) a subset of Unified Modeling Language (UML) diagrams, called Coretto UML (C-UML), which allows designers to describe the components of the system and their behavior through several kinds of diagrams (e.g., state machine diagrams, sequence diagrams, activity diagrams, interaction overview diagrams), and stereotypes taken from the UML Profile for Modeling and Analysis of Real-Time and Embedded Systems; (ii) a formal semantics of C-UML diagrams, defined through formulae of the metric temporal logic Tempo Reale ImplicitO (TRIO); and (iii) a tool, called Corretto, which implements the aforementioned semantics and allows users to carry out formal verification tasks on modeled systems. We validate the feasibility of our approach through a set of different case studies, taken from both the academic and the industrial domain

A real-time execution semantics for UML activity diagrams

We define a formal execution semantics for UML activity diagrams that is appropriate for workflow modelling. Our semantics is aimed at the requirements level by assuming that software state changes do not take time. It is based upon the STATEMATE semantics of statecharts, extended with some transactional properties to deal with data manipulation. Our semantics also deals with real-time and multiple state instances. We first give an informal description of our semantics and then formalise this in terms of transition systems

Tool-Supported Formal Analysis of Real-Time Systems

In dieser Arbeit werden Verfahren zur effizienten, benutzerfreundlichen Analyse von Echtzeitsystemen entwickelt. Ziel ist die Verbesserung der Entwurfsqualität hinsichtlich von dynamischen/zeitlichen Programmabläufen möglichst ohne zusätzlichen Aufwand seitens des Entwicklers. Dieses erfordert ein Aufsetzen auf Spezifikationen, die bei der Entwicklung ohnehin anfallen. Konkret wird daher untersucht, wie sich Modelle der Unified Modeling Language mit formalen Methoden analysieren lassen und wie diese Analyse automatisiert werden kann. Es wird geklärt, welche Teilmenge von Modellen als Ausgangspunkt für eine dynamische Analyse geeignet ist. Dabei werden in dieser Arbeit drei Analyseziele definiert, die jeweils eine eigene Sprachdefinition erfordern. Wichtiger Bestandteil der Arbeit ist die Realisierung einer automatisierten Analyse. Dabei wird auf formale Techniken wie Model-Checking und auf algorithmische Lösungen der Scheduling-Theorie zurückgegriffen. Es wird nachgewiesen, dass sich verschiedene theoretische Lösungsansätze unter dem Dach einer einheitlichen Notation für den Anwender transparent anwenden lassen und in der Summe zu einer deutlichen Verbesserung der Software- Qualität in einem besonders komplexen Anwendungsgebiet beitragen können.In this work, methods for an efficient and user friendly analysis of real-time systems are developed. The intention is an improvement of the quality of the software design regarding the dynamic/temporal execution runs without additional efforts of the developer. This requires the use of specification models, which are common in the developing process, as basis for the analysis. Therefore, formal analysis of the Unified Modeling Language (UML) is investigated and how this analysis can be automated. As precondition, it is investigated, which subset of UML models is well suited for a dynamic analysis. Three domains of an analysis are defined, which requires their own input language definition. An important part of this work is the development of an automated analysis. Therefore, formal methods like model checking and algorithms of the scheduling theory are used. It is shown, that different solution approaches can be hidden behind a well-known notation for improving the quality of software design in a complex application domain

Evaluation and development models for business processes

Most organisations are working hard to improve their performance and to achieve competitive advantage over their rivals. They may accomplish these ambitions through carrying out their business processes more effectively. Hence it is important to consider such processes and look for ways in which they can be improved. Any organisational business process encompasses several elements that interact and collaborate with each other to achieve the required objectives. These elements can be classified into hard aspects, which deal with tangible issues related to the software system or the technology in general, and soft aspects, which deal with issues related to the human part of the business process. If the business process needs to be analysed and redesigned to improve its performance, it is important to use a suitable approach or intervention that takes into account all of these elements. This thesis proposes an approach to investigate organisational business processes by considering both soft and hard aspects. The approach, Soft Workflow Modelling (SWfM), is developed as a result of reviewing several workflow products and models using a developed workflow perspectives framework which involves several perspectives covering the soft and hard aspects of the workflow system. The SWfM approach models the organisational business process as a workflow system by handling the various perspectives of the workflow perspectives framework. This approach combines the Soft Systems Methodology (SSM) with the Unified Modelling Language (UML), as a standard modelling language of the object-oriented paradigm. The basic framework adopted is that of SSM with the inclusion of UML diagrams and techniques to deal with the aspects that SSM cannot handle. The approach also supports SSM by providing a developed tool to assist in constructing a conceptual model which is considered as the basis to model the workflow system. A case study is developed for illustrative purposes.EThOS - Electronic Theses Online ServiceGBUnited Kingdo