<p>A <i>method</i> for designing workflow systems which satisfy performance requirements is proposed in this thesis. Integration of human and computerised performance is particularly useful for workflow systems where human and computerised processes are intertwined. The proposed <i>framework </i>encompasses human and computerised resources. </p><p>Even though systematic performance engineering is not common practice in information system development, current, <i>best</i> practice shows that performance engineering of software is feasible, e.g. the SPE method by Connie U. Smith. Contemporary approaches to performance engineering focus on <i>dynamic </i>models of resource contention, e.g. queueing networks and Petri nets. Two difficulties arise for large-scale information systems. The first difficulty is to estimate appropriate <i>parameters </i>which capture the properties of the software and the organisation. The second difficulty is to maintain an <i>overveiw </i>of a complex model, which is essential both to guide the choice of parameters and to ensure that the oerformance engineering process is an intregal part of the wider system development process.</p><p>The proposed method is based on the <i>static</i> performance modelling method Structure and Performance (SP) developed by Peter h: Hughes. SP provides a suitable bridge between contemporary CASE tools and traditional dynamic approaches to performance evaluation, in particular because it adresses the problems of parameterisation and overveiw identified above.</p><p>The method is explored and illustrated with two case studies. The <i>Blood Bank Case Study</i> comprised performance engineering of a transaction-oriented information system, showing the oractical feasibility of integrating the method with CASE tools. The <i>Gas Sales</i> <i>Telex Administration Case Study</i> for Statoil looked at performance engineering of a workfloww system for telex handling, and consisted of performance modelling of human activity in interaction with a Lotus Notes computer platform.</p><p>The latter case study demonstrated the feasibility of the framework.</p>

A method for designing workflow systems which satisfy performance requirements is proposed in this thesis. Integration of human and computerised performance is particularly useful for workflow systems where human and computerised processes are intertwined. The proposed framework encompasses human and computerised resources. Even though systematic performance engineering is not common practice in information system development, current, best practice shows that performance engineering of software is feasible, e.g. the SPE method by Connie U. Smith. Contemporary approaches to performance engineering focus on dynamic models of resource contention, e.g. queueing networks and Petri nets. Two difficulties arise for large-scale information systems. The first difficulty is to estimate appropriate parameters which capture the properties of the software and the organisation. The second difficulty is to maintain an overveiw of a complex model, which is essential both to guide the choice of parameters and to ensure that the oerformance engineering process is an intregal part of the wider system development process. The proposed method is based on the static performance modelling method Structure and Performance (SP) developed by Peter h: Hughes. SP provides a suitable bridge between contemporary CASE tools and traditional dynamic approaches to performance evaluation, in particular because it adresses the problems of parameterisation and overveiw identified above. The method is explored and illustrated with two case studies. The Blood Bank Case Study comprised performance engineering of a transaction-oriented information system, showing the oractical feasibility of integrating the method with CASE tools. The Gas Sales Telex Administration Case Study for Statoil looked at performance engineering of a workfloww system for telex handling, and consisted of performance modelling of human activity in interaction with a Lotus Notes computer platform. The latter case study demonstrated the feasibility of the framework.

<p>Denne hovedoppgaven dreier seg omkring et konsept jeg har valgt å kalle for <i>mikronavigering</i>. Dette innebærer at jeg har sett nærmere på hvordan mobile applikasjoner, ved å utnytte informasjon som karakteriserer brukerens situasjon, kan være med på å orientere brukeren om hans omgivelser i en bygning eller et mindre område. Hensikten med dette studiet har vært å betrakte både muligheter og utfordringer tilknyttet det å nyttiggjøre forskjellige typer situasjonsbetinget informasjon (f.eks. lokasjon og kurs), eller <i>kontekst</i> for at mobile applikasjoner skal bli mer brukervennlige, fleksible og adaptive. Denne typen mobile tjenester har på mange måter et potensiale i seg til å skape en enklere og rikere menneskemaskin interaksjon. Særlig gjelder dette for de interaksjonsmiljøene som har vært i fokus i forbindelse med dette studiet, hvor omgivelser og brukerkrav skifter raskt. Samtidig har koplingen mellom mobil IT og kontekst også vært med på å skape nye utfordringer tilknyttet brukerinteraksjonen med slike verktøy.</p>

Denne hovedoppgaven dreier seg omkring et konsept jeg har valgt å kalle for mikronavigering. Dette innebærer at jeg har sett nærmere på hvordan mobile applikasjoner, ved å utnytte informasjon som karakteriserer brukerens situasjon, kan være med på å orientere brukeren om hans omgivelser i en bygning eller et mindre område. Hensikten med dette studiet har vært å betrakte både muligheter og utfordringer tilknyttet det å nyttiggjøre forskjellige typer situasjonsbetinget informasjon (f.eks. lokasjon og kurs), eller kontekst for at mobile applikasjoner skal bli mer brukervennlige, fleksible og adaptive. Denne typen mobile tjenester har på mange måter et potensiale i seg til å skape en enklere og rikere menneskemaskin interaksjon. Særlig gjelder dette for de interaksjonsmiljøene som har vært i fokus i forbindelse med dette studiet, hvor omgivelser og brukerkrav skifter raskt. Samtidig har koplingen mellom mobil IT og kontekst også vært med på å skape nye utfordringer tilknyttet brukerinteraksjonen med slike verktøy.

<p>This work is about supporting user interface design by means of explicit design representations, in particular models.</p><p>We take as a starting point two different development traditions: the formal, analytic, topdown engineering approach and the informal, synthetic, bottom-up designer approach. Both are based on specific design representations tailored to the respective approaches, and are found to have strengths and weaknesses. We conclude that different representations should be used during user interface design, based on their specific qualities and the needs of the design process.</p><p>To better understand the use of design representations a framework for classifying them is developed. A design representation may be classified along three dimensions: the perspective (problem- or solution-oriented) of the representation, the granularity of the objects described and the degree of formality of the representation and its language. Any design approach must provide representation languages that cover the whole classification space to be considered complete. In addition, the transitions between different representations within the representation space must be supported, like moving between task-based and interaction- oriented representations or up and down a hierarchic model. Movements between representations with different degrees of formality are particularly important when combining user-centered design with a model-based approach.</p><p>The design representation classification framework has guided the development of diagrambased modelling languages for the three main perspectives of user interface design, tasks, abstract dialogue and concrete interaction. The framework has also been used for evaluating the languges. A set-based conceptual modelling language is used for domain modelling within all these perspectives. The task modelling language is designed as a hybrid of floworiented process languages and traditional hierarchical sequence-oriented task languages.</p><p>Key features are tight integration with the domain modelling language, expressive and flexible notation and support for classification of task structures. The language for modelling abstract dialogue is based on the interactor abstraction for expressing composition and information flow, and the Statecharts language for activation and sequencing. Parameterized interactors are supported, to provide means of expressing generic and reusable dialogue structures. Modelling of concrete interaction is supported by a combination of the dialogue and domain modelling languages, where the former captures the functionality and behavior and the latter covers concepts that are specific for the chosen interaction style.</p><p>The use of the languages in design is demonstrated in a case study, where models for tasks, dialogue and concrete interaction are developed. The case study shows that the languages support movements along the perspective, granularity and formality dimensions.</p>

This work is about supporting user interface design by means of explicit design representations, in particular models. We take as a starting point two different development traditions: the formal, analytic, topdown engineering approach and the informal, synthetic, bottom-up designer approach. Both are based on specific design representations tailored to the respective approaches, and are found to have strengths and weaknesses. We conclude that different representations should be used during user interface design, based on their specific qualities and the needs of the design process. To better understand the use of design representations a framework for classifying them is developed. A design representation may be classified along three dimensions: the perspective (problem- or solution-oriented) of the representation, the granularity of the objects described and the degree of formality of the representation and its language. Any design approach must provide representation languages that cover the whole classification space to be considered complete. In addition, the transitions between different representations within the representation space must be supported, like moving between task-based and interaction- oriented representations or up and down a hierarchic model. Movements between representations with different degrees of formality are particularly important when combining user-centered design with a model-based approach. The design representation classification framework has guided the development of diagrambased modelling languages for the three main perspectives of user interface design, tasks, abstract dialogue and concrete interaction. The framework has also been used for evaluating the languges. A set-based conceptual modelling language is used for domain modelling within all these perspectives. The task modelling language is designed as a hybrid of floworiented process languages and traditional hierarchical sequence-oriented task languages. Key features are tight integration with the domain modelling language, expressive and flexible notation and support for classification of task structures. The language for modelling abstract dialogue is based on the interactor abstraction for expressing composition and information flow, and the Statecharts language for activation and sequencing. Parameterized interactors are supported, to provide means of expressing generic and reusable dialogue structures. Modelling of concrete interaction is supported by a combination of the dialogue and domain modelling languages, where the former captures the functionality and behavior and the latter covers concepts that are specific for the chosen interaction style. The use of the languages in design is demonstrated in a case study, where models for tasks, dialogue and concrete interaction are developed. The case study shows that the languages support movements along the perspective, granularity and formality dimensions.