15 research outputs found

    Semantics Through Pictures: towards a diagrammatic semantics for object-oriented modelling notations

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    An object-oriented (OO) model has a static component, the set of allowable snapshots or system states, and a dynamic component, the set of filmstrips or sequences of snapshots. Diagrammatic notations, such as those in UML, each places constraints on the static and/or dynamic models. A formal semantics of OO modeling notations can be constructed by providing a formal description of (i) sets of snapshots and filmstrips, (ii) constraints on those sets, and (iii) the derivation of those constraints from diagrammatic notations. In addition, since constraints are contributed by many diagrams for the same model, a way of doing this compositionally is desirable. One approach to the semantics is to use first-order logic for (i) and (ii), and theory inclusion with renaming, as in Larch, to characterize composition. A common approach to (iii) is to bootstrap: provide a semantics for a kernel of the notation and then use the kernel to give a semantics to the other notations. This only works if a kernel which is sufficiently expressive can be identified, and this is not the case for UML. However, we have developed a diagrammatic notation, dubbed constraint diagrams, which seems capable of expressing most if not all static and dynamic constraints, and it is proposed that this be used to give a diagrammatic semantics to OO models

    Applying formal methods to standard development: the open distributed processing experience

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    Since their introduction, formal methods have been applied in various ways to different standards. This paper gives an account of these applications, focusing on one application in particular: the development of a framework for creating standards for Open Distributed Processing (ODP). Following an introduction to ODP, the paper gives an insight into the current work on formalising the architecture of the Reference Model of ODP (RM-ODP), highlighting the advantages to be gained. The different approaches currently being taken are shown, together with their associated advantages and disadvantages. The paper concludes that there is no one all-purpose approach which can be used in preference to all others, but that a combination of approaches is desirable to best fulfil the potential of formal methods in developing an architectural semantics for OD

    Theoretical Foundation for Relationship Construct in Information Modeling --Relation Element Theory

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    Information modeling is a critical process in software development. One of the key constructs in information modeling is the relationship construct. Though commonly used, the relationship construct is poorly defined and lacks a strong theoretical foundation. The objectives of this research are to define and classify the various relationships based on a theory in linguistic known as the relation element theory. This paper describes the theory, relates the theory to the relationship construct, and discusses the implication of the theory on the relationship construct

    Characterising aggregations with existence dependency.

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    Abstract: The concept of aggregation is considered as one of the basic principles in object-oriented analysis. There is however no standard definition of this concept and each object-oriented analysis method has its own definition of aggregation. The aim of this paper is not to discuss the different types of aggregation that exist. However, having assessed the complexity of the concept, we will illustrate how a basic set of formal concepts is sufficient to define of the structural and behavioral aspects of different existing flavours of aggregation. If a development method wants to offer a rich concept such as aggregation, it can define the semantics of the desired flavour of the aggregation using these core formal concepts. Analysts then have the choice to use the aggregation defined by the method or to fall back on the core concepts if a different flavour of aggregation is needed to model the situation at hand.Principles; Model;

    Object Modelling and Common Objects in the RM-ODP Information Language

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    This paper argues that the Reference-Model for Open Distributed Processing (RM-ODP) is a suitable basis for developing new standards pertaining to domain architectures, common business facilities, and common objects. However, the RM-ODP is difficult to understand, and there appears to be several divergent interpretations of it. This paper proposes and discusses an interpretation of information modelling that is both fully consistent with the ODP foundations, and compatible with some of the best practice in object-oriented software engineering

    Enhancing dependability through flexible adaptation to changing requirements

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    This paper describes an architectural approach that facilitates the dynamic adaptation of systems to changing domain rules. The approach relies on 'coordination contracts', a modelling and implementation primitive we have developed for run-time reconfiguration. Our framework includes an engine that, whenever a service is called, checks the domain rules that are applicable and configures the response of the service before proceeding with the call. This approach enhances dependability in two essential ways: on the one hand, it guarantees that system execution is always consistent with the domain logic because service response is configured automatically (i.e., without any need for programmer intervention); on the other hand, it makes it possible for changes to be incorporated into existing domain rules, and from new rules to be created, with little effort, because coordination contracts can be superposed dynamically without having to change neither the client nor the service code. Our approach is illustrated through a case study in financial systems, an area in which dependability arises mainly in the guise of business concerns like adherence to agreed policies and conditions negotiated on a case-by-case basis. We report on an information system that ATX Software developed for a company specialised in recovering bad credit. We show in particular how, by using this framework, we have devised a way of generating rule-dependent SQL code for batch-oriented services

    Influence of an adventure learning program, using group adventure initiative tasks, on participant self-esteem

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    The purpose of this study was to assess the influence of an adventure learning program, based on participation in group adventure initiative tasks (GAITs), on participant self-esteem and, further, to examine any associated gender differences in the dependent variable. The study took place within the framework of the \u27Group Dynamics in Action\u27 unit offered at the University of South Australia, Underdale Campus, in semester 2, 1994. The course included participation in group adventure initiative tasks, the identification and examination of group dynamic processes, the investigation of individual roles within the small group and the review of these processes in the group setting. The program also included an experience on a high ropes course. Both quantitative and qualitative data was gathered to gain insight into gender differences and their relationship to the dependent variable and also to provide insight into any discrepancy in outcomes between males and females with regard to participation in group adventure initiative tasks. The sample set of participants was drawn from undergraduate students studying at the University of South Australia in the Bachelor of Teaching (Primary), Bachelor of Education (Secondary Physical Education Teaching) and Bachelor of Applied Science (Exercise and Sport Science) courses. Subjects were assigned to either experimental or control conditions and the experimental group were then randomly assigned to one of three treatment groups. Sixty one (N = 61) male and female subjects were tested pre and post-treatment period. Psychological tests included the Coopersmith Self Esteem Inventory (Coopersmith 1981) and an adaptation of Coopersmith\u27s Behaviour Rating Form (Coopersmith 1967). Qualitative data was gathered using Kuhn\u27s Twenty Statements Test (Kuhn and McPartland 1954), a self-esteem questionnaire, observations made by the researcher and other staff about subjects interactions and from weekly journals kept by subjects throughout the treatment. The duration of the treatment period was 14 weeks consisting of 14, 2 hour seminars

    Modelo Genérico de Relacionamentos na Organização da Informação Legislativa e Jurídica

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    In most of the time information does not work in an isolate form and it always belongs to one context, making relationships with other entities. Legislative and legal information, in a certain way, is characterized by their high degree of relationships. Laws, bills, legal cases and doctrine are connected by several forms, creating a rich network of information. Efforts done for the organization of information generate artificial models that try to represent the real world, creating systems and schemes of concepts used in the classification processes and indexing of information resources. This research had the main objective of proposing a Generic Model of Relationship (GMR), based in a simple constructs which permitted the establishment of relationships between concepts and information units. In the conception of GMR were used Ingetraut Dahlberg’s Theory of Concept and the models CIDOC CRM (ISO 21.117:2006), FRBROO and Topic Maps (ISO 13.250:1999). The identification of relationship and the characteristics of information units in a legal domain were collected in the project "Coletânea Brasileira de Normas e Julgados de Telecomunicações", using the methodology of Action Research. Besides the development of GMR and its application in the legislative and legal information domains, the research also contributed with the definitions of one identification system of documents versions and a new meaning for the term “information unit”

    Incorporating design explanation within formal object-oriented method (FOOM)

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    Requirements engineering is a commencing phase in the development of either software applications or information systems. It is concerned with understanding and specifying the customer\u27s requirements of the system to be delivered. Throughout the literature, this is agreed to be one of the most crucial and, unfortunately, problematic phases in development. Despite the diversity of research directions, approaches and methods, the question of process understanding and management is still limited. Among contemporary approaches to the improvement of the current practice of Requirements Engineering, Formal Object-Oriented Method (FOOM) has been introduced as a new promising solution. The FOOM approach to requirements engineering is based on a synthesis of socio-organisational theory, the object-oriented approach, and mathematical formal specification. The entire FOOM specification process is evolutionary and involves a large volume of changes in requirements. During this process, requirements evolve through various forms of informal, semi-formal, and formal while maintaining a semantic link between these forms and, most importantly, conforming to the customer\u27s requirements. A deep understanding of the complexity of the requirements model and its dynamics is critical in improving requirements engineering process management. This thesis investigates the benefits of documenting both the evolution of the requirements model and the rationale for that evolution. Design explanation explains and justifies the deliberations of, and decisions made during, the design activity. In this thesis, design explanation is used to describe the requirements engineering process in order to improve understandability of, and traceability within, the evolving requirements specification. The design explanation recorded during this research project is also useful in assisting the researcher in gaining insights into the creativity and opportunistic characteristics of the requirements engineering process. This thesis offers an interpretive investigation into incorporating design explanation within FOOM in order to extend and advantage the method. The researcher\u27s interpretation and analysis of collected data highlight an insight-driven and opportunistic process rather than a strictly and systematically predefined one. In fact, the process was not smoothly evolutionary, but involved occasional \u27crisis\u27 points at which the model was reconceptualised, simplified and restructured. Therefore, contributions of the thesis lie not only in an effective incorporation of design explanation within FOOM, but also a deep understanding of the dynamic process of requirements engineering. The new understanding of the complexity of the requirements model and its dynamics suggests new directions for future research and forms a basis for a new approach to process management
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