Duration calculus semantics for statecharts

Statecharts and Duration Calculus are two formalisms used in the development of reactive systems. Statecharts provide a powerful visual formalism to specify systems. Duration Calculus is a formal logic to specify and reason about temporal requeriments. In this work, we propose a description of statecharts semantics using Duration Calculus. Thus we build a common semantic model for Duration Calculus speci¯cations and statecharts. The formalization is done in two steps. First, the structure of a statechart is represented using Duration Calculus formula. Then, the semantics of the execution of a step is introduced.Eje: TeoríaRed de Universidades con Carreras en Informática (RedUNCI

Duration calculus semantics for statecharts

Statecharts and Duration Calculus are two formalisms used in the development of reactive systems. Statecharts provide a powerful visual formalism to specify systems. Duration Calculus is a formal logic to specify and reason about temporal requeriments. In this work, we propose a description of statecharts semantics using Duration Calculus. Thus we build a common semantic model for Duration Calculus speci¯cations and statecharts. The formalization is done in two steps. First, the structure of a statechart is represented using Duration Calculus formula. Then, the semantics of the execution of a step is introduced.Eje: TeoríaRed de Universidades con Carreras en Informática (RedUNCI

Duration calculus semantics for statecharts

Statecharts and Duration Calculus are two formalisms used in the development of reactive systems. Statecharts provide a powerful visual formalism to specify systems. Duration Calculus is a formal logic to specify and reason about temporal requeriments. In this work, we propose a description of statecharts semantics using Duration Calculus. Thus we build a common semantic model for Duration Calculus speci¯cations and statecharts. The formalization is done in two steps. First, the structure of a statechart is represented using Duration Calculus formula. Then, the semantics of the execution of a step is introduced.Eje: TeoríaRed de Universidades con Carreras en Informática (RedUNCI

Xchart : um modelo de especificação e implementação de gerenciadores de dialogos

Orientador: Hans Kurt Edmund LiesenbergTese (doutorado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: O gerenciador de diálogo é um dos componentes mais complexos de uma interface e continua, em grande parte, sendo codificado manualmente em linguagens de programação convencionais. Isto contribui para elevar os custos de desenvolvimento e inibir alterações, que são indispensáveis ao desenvolvimento de interfaces. Essa dissertação propõe a linguagem Xchart e um ambiente de apoio voltados para o desenvolvimento de gerenciadores de diálogo. Xchart possui recursos para capturar adequadamente as funções desses componentes de interfaces. Cada gerenciador é especificado através de um conjunto de diagramas. A semântica formal de Xchart permite que esses diagramas sejam automaticamente executados por um interpretador. Em tempo de execução, instâncias desses diagramas podem ser criadas dinamicamente e executadas concorrentemente, possivelmente em um sistema distribuído, apoiadas pelo sistema de execução de XchartAbstract: Not informedDoutoradoDoutor em Ciência da Computaçã

Conceptual modelling: A psychological perspective.

This thesis describes the formulation and experimental use of psychological principles that apply to conceptual modelling as practised during information systems development. The principles address cognition (perception, memory and mental models) and group dynamics. The aim is to determine whether application of fundamental psychological principles can help to make modellers, especially those who are relatively inexperienced, more effective. An experimental graphical modelling technique (method 'X') is presented that conforms to the psychological principles, together with a supporting software tool for visual construction of models in the design of typical business database systems. The effectiveness of both inexperienced and expert modellers using method 'X' in real business situations was compared with that of modellers using conventional object modelling. Data was gathered in a series of field experiments using participant observation, questionnaires, and interviews and by analysing the resulting models. With conventional object modelling, untrained modellers produced results that were grossly incomplete and incorrect (22-35%, on average). Using method 'X', untrained modellers produced models that were almost complete and correct (better than 82%). Significant productivity gains were observed with method 'X' (approximately 150% for expert modeller and over 450% for untrained modellers). For an expert modeller no measurable differences in quality were observed between methods, but the modeller regarded the quality of method 'X' models as better and expressed a preference method 'X' over the conventional approach. The results appear to support the idea of re-engineering conceptual modelling practice according to psychological first principles. The fact that more dramatic performance improvements were observed for inexperienced modellers suggests that modelling need not require a high degree of expertise, if methods and tools are adapted appropriately. The results could be exploited to empower untrained modellers, such as end users, who wish to develop large software systems but lack access to the skills of trained IT professionals

Introduction to design choices in the semantics of Statecharts

The notion of reactive system and the language Statecharts are introduced. For the first time the rationale behind the design decisions of Statecharts is explained in relation to the specific nature of reactive systems