STAIRS - Understanding and Developing Specifications Expressed as UML Interaction Diagrams

STAIRS is a method for the step-wise, compositional development of interactions in the setting of UML 2.x. UML 2.x interactions, such as sequence diagrams and interaction overview diagrams, are seen as intuitive ways of describing communication between different parts of a system, and between a system and its users. STAIRS addresses the challenges of harmonizing intuition and formal reasoning by providing a precise understanding of the partial nature of interactions, and of how this kind of incomplete specifications may be consistently refined into more complete specifications. For understanding individual interaction diagrams, STAIRS defines a denotational trace semantics for the main constructs of UML 2.x interactions. The semantic model takes into account the partiality of interactions, and the formal semantics of STAIRS is faithful to the informal semantics given in the UML 2.x standard. For developing UML 2.x interactions, STAIRS defines a number of refinement relations corresponding to basic system development steps. STAIRS also defines matching compliance relations, for relating interactions to real computer systems. An important feature of STAIRS is the distinction between underspecification and inherent nondeterminism. Underspecification means that there are several possible behaviours serving the same overall purpose, and that it is sufficient for a computer system to perform only one of these. On the other hand, inherent nondeterminism is used to capture alternative behaviours that must all be possible for an implementation. A typical example is the tossing of a coin, where both heads and tails should be possible outcomes. In some cases, using inherent nondeterminism may also be essential for ensuring the necessary security properties of a system

The pragmatics of STAIRS

STAIRS is a method for the compositional development of interactions in the setting of UML 2.0. In addition to defining denotational trace semantics for the main aspects of interactions, STAIRS focuses on how interactions may be developed through successive refinement steps. In this tutorial paper, we concentrate on explaining the practical relevance of STAIRS. Guidelines are given on how to create interactions using the different STAIRS operators, and how these may be refined. The pragmatics is illustrated by a running example

An Aspect-Oriented Approach for Spatial Concerns in Web Applications

The growing availability of on-line geographical information, since the advent of open map servers in the 2000s, originated a new generation of Web applications, those which combine “conventional” Web functionality with typical features of traditional Geographic Application System (GIS). The rapid growth in number and complexity of Web applications with geo-referenced data together with the need to support fast requirements change, demands for increased modularity. The volatility of some of these changing requirements, both in the scope of their geographic nature or in the period of time in which they are valid, stresses the importance of the applications’ modularity. A solution is to take into consideration the crosscutting nature of these requirements and decouple their realization from “conventional” requirements in separate software modules. This paper proposes an end-to-end Aspect-Oriented approach to deal with spatial requirements from the early stages of applications development throughout to implementation. A significant contribution of this approach is the characterization of the most common spatial requirements in Web-GIS applications. The result is the improvement of the overall application’s modularity, thus facilitating its evolution.Laboratorio de Investigación y Formación en Informática Avanzad

Freeform User Interfaces for Graphical Computing

報告番号: 甲15222 ; 学位授与年月日: 2000-03-29 ; 学位の種別: 課程博士 ; 学位の種類: 博士(工学) ; 学位記番号: 博工第4717号 ; 研究科・専攻: 工学系研究科情報工学専

A Mobile ECG Monitoring System with Context Collection

An objective of a health process is one where patients can stay healthy with the support of expert medical advice when they need it, at any location and any time. An associated aim would be the development of a system which places increased emphasis on preventative measures as a first point of contact with the patient. This research is a step along the road towards this type of preventative healthcare for cardiac patients. It seeks to develop a smart mobile ECG monitoring system that requests and records context information about what is happening around the subject when an arrhythmia event occurs. Context information about the subject’s activities of daily living will, it is hoped, provide an enriched data set for clinicians and so improve clinical decision making. As a first step towards a mobile cardiac wellness guidelines system, the focus of this work is to develop a system that can receive bio-signals wirelessly, analyzing and storing the bio-signal in a handheld device and can collect context information when there are significant changes in bio-signs. For this purpose the author will use a low cost development environment to program a state of the art wireless prototype on a handheld computer that detects and responds to changes in the heart rate as calculated form the interval between successive heart beats. Although the general approach take in this work could be applied to a wide range of bio-signals, the research will focus on ECG signals. The pieces of the system are, A wireless receiver, data collection and storage module An efficient real time ECG beat detection algorithm A rule based (Event-Condition-Action) interactive system A simple user interface, which can request additional information form the user. A selection of real-time ECG detection algorithms have been investigated and one algorithm was implemented in MATLAB [110] and then in Java [142] for this project. In order to collect ECG signals (and in principle any signals) the generalised data collection architecture has also been developed utilizing Java [142] and Bluetooth [5] technology. This architecture uses an implementation of the abstract factory pattern [91] to ensure that the communication channel can be changed conveniently. Another core part of this project is a “wellness” guideline based on Event-Condition-Action (E-C-A) [68] production rule approach that originated in active databases. The work also focuses on design of a guideline based expert system which an E-C-A based implementation will be fully event driven using the Java programming language. Based on the author’s experience and the literature review, some important issues in mobile healthcare along with the corresponding reasons, consequences and possible solutions will be presented

A model driven approach to analysis and synthesis of sequence diagrams

Software design is a vital phase in a software development life cycle as it creates a blueprint for the implementation of the software. It is crucial that software designs are error-free since any unresolved design-errors could lead to costly implementation errors. To minimize these errors, the software community adopted the concept of modelling from various other engineering disciplines. Modelling provides a platform to create and share abstract or conceptual representations of the software system – leading to various modelling languages, among them Unified Modelling Language (UML) and Petri Nets. While Petri Nets strong mathematical capability allows various formal analyses to be performed on the models, UMLs user-friendly nature presented a more appealing platform for system designers. Using Multi Paradigm Modelling, this thesis presents an approach where system designers may have the best of both worlds; SD2PN, a model transformation that maps UML Sequence Diagrams into Petri Nets allows system designers to perform modelling in UML while still using Petri Nets to perform the analysis. Multi Paradigm Modelling also provided a platform for a well-established theory in Petri Nets – synthesis to be adopted into Sequence Diagram as a method of putting-together different Sequence Diagrams based on a set of techniques and algorithms

Simulation and optimization model for the construction of electrical substations

One of the most complex construction projects is electrical substations. An electrical substation is an auxiliary station of an electricity generation, transmission and distribution system where voltage is transformed from high to low or the reverse using transformers. Construction of electrical substation includes civil works and electromechanical works. The scope of civil works includes construction of several buildings/components divided into parallel and overlapped working phases that require variety of resources and are generally quite costly and consume a considerable amount of time. Therefore, construction of substations faces complicated time-cost-resource optimization problems. On another hand, the construction industry is turning out to be progressively competitive throughout the years, whereby the need to persistently discover approaches to enhance construction performance. To address the previously stated afflictions, this dissertation makes the underlying strides and introduces a simulation and optimization model for the execution processes of civil works for an electrical substation based on database excel file for input data entry. The input data include bill of quantities, maximum available resources, production rates, unit cost of resources and indirect cost. The model is built on Anylogic software using discrete event simulation method. The model is divided into three zones working in parallel to each other. Each zone includes a group of buildings related to the same construction area. Each zone-model describes the execution process schedule for each building in the zone, the time consumed, percentage of utilization of equipment and manpower crews, amount of materials consumed and total direct and indirect cost. The model is then optimized to mainly minimize the project duration using parameter variation experiment and genetic algorithm java code implemented using Anylogic platform. The model used allocated resource parameters as decision variables and available resources as constraints. The model is verified on real case studies in Egypt and sensitivity analysis studies are incorporated. The model is also validated using a real case study and proves its efficiency by attaining a reduction in model time units between simulation and optimization experiments of 10.25% and reduction in total cost of 4.7%. Also, by comparing the optimization results by the actual data of the case study, the model attains a reduction in time and cost by 13.6% and 6.3% respectively. An analysis to determine the effect of each resource on reduction in cost is also presented