A Representational Framework for Scenarios of System Use

Scenarios are becoming widely used in three areas of system development: software engineering, human–computer interaction (HCI), and organisational process design. There are many reasons to use scenarios during system design. The one usually advanced in support of the practice is to aid the processes of validating the developers’ understanding of the customers’ or users’ work practices, organisational goals and structures, and system requirements. All three areas identified above deal with these processes, and not surprisingly this has given rise to a profusion of scenario-based practices and representations. Yet there has been little analysis of why scenarios should be useful, let alone whether they are. Only by having such a framework for understanding what scenarios are, and what they are for, can we begin to evaluate different scenario approaches in specific development contexts. This paper is a contribution toward such a framework. We lay out a space of representational possibilities for scenarios and enumerate a set of values or criteria that are important for different uses of scenarios. We then summarise several salient representations drawn from the software engineering, HCI, and organisational process design communities to clarify how these representational choices contribute to or detract from the goals of the respective practices. Finally, we discuss how scenario representations from one area of design may be useful in others, and we discuss the relationship between these representations and other significant early-design and requirements engineering practices.     

Implementing reuse with RAD tools' native objects

Developers and project managers need to understand how to constrain project requirements to reap the reuse advantages that RAD (rapid application development) tools offer. Designing exclusively within the capabilities of RAD Business Objects can stabilize projects, even enough to support larger applications. Four RAD tools are presented which use de facto standard RAD Business Objects, but each represents a different design for RAD tools: Microsoft's Visual Basic; IBM's Lotus Notes; Magic MSE's Magic; and Powersoft/Sybase's Powerbuilder. RAD tools are moving toward innovations in two areas: language based programming alternatives and software design support, and both these areas are discussed     

Current research in robotics and automation-electronic prototyping

Electronic prototyping, i.e. building a computer model of an object to verify its design, faces a number of obstacles. The Cornell modeling and simulation project, which was created to develop the necessary science base to overcome these barriers, is discussed. In particular, the project's progress in improving robustness of solid modelers and its ongoing research in electronic prototyping are examined. A key component of the project, a model-driven simulator capable of supporting a wide range of multidisciplinary research, is described     

The utility of rapid application development in large-scale, complex projects

This paper describes an investigation into the utility of an agile development approach known as rapid application development (RAD) within a large-scale development project conducted within the public sector in the UK. Features of RAD as an 'agile' information systems development method (ISDM) are discussed and previous research identifying properties of development environments most conducive to its application are described. A case study is then presented based upon a long-term qualitative investigation of the 'unbundling' of a commercial RAD-like ISDM. The evidence from this case leads us to question established wisdom in relation to appropriate adoption and application of agile development within large-scale and complex development environments.     

基于原型设计的人机交互课程实验方案

人机交互课程是实践性很强的一门课。实验是人机交互课程的重要组成部分。现阶段,国内高校的人机交互课程的学时数普遍不多。没有足够的学时造成无法通过软件开发项目实战来开展人机交互设计实践。一种对策是开展软件界面原型设计实验。描述基于原型设计的人机交互课程实验方案。首先描述了实验目的,接着描述实验任务和目标,再接着重点描述了实验流程,然后描述实验成果验收的办法。最后总结了该实验方案的优势和面临的问题。     

Virtual Video Prototyping

Computing power is an integrated part of our physical environment, and since our physical environment is three-dimensional, the virtual studio technology, with its unique potential for visualizing digital 3D objects and environments along with physical objects, offers an obvious path to pursue in order to envision future usage scenarios in the domain of pervasive computing.We label the work method virtual video prototyping, which grew out of a number of information systems design techniques along with approaches to visualization in the field of architecture and set design.We present a collection of virtual video prototyping cases and use them as the platform for a discussion, which pinpoint advantages and disadvantages of working with virtual video prototyping as a tool for communication, experimentation and reflection in the design process. Based on more than ten cases we have made the observations that virtual video prototypes 1) are a powerful medium of communication in development teams and for communication with industry partners and potential investors, 2) support both testing and generating ideas 3) are particular suited for addressing spatial issues and new ways of interacting. In addition practical use of virtual video prototypes has indicated the need to take into account some critical issues including a) production resources, b) hand-on experience, and c) the seductive power of virtual video prototypes.     

Rapid application development (RAD): an empirical review

Rapid application development (RAD) is an approach to information systems (IS) development which is much discussed in the practitioner literature. However, there is comparatively little research data on this topic. This paper forms a report of the results of a multi-disciplinary research project which has been studying this development approach for the last three years. The paper discusses seven case studies of RAD projects and compares each to issues relating to a number of RAD principles as represented in methodologies such as the recent open standard known as dynamic systems development method. We conclude with a discussion of a number of important questions relating to further research on RAD.     

The Role of Cognitive Modeling for User Interface Design Representations: An Epistemological Analysis of Knowledge Engineering in the Context of Human-Computer Interaction

In this paper we review some problems with traditional approaches for acquiring and representing knowledge in the context of developing user interfaces. Methodological implications for knowledge engineering and for human-computer interaction are studied. It turns out that in order to achieve the goal of developing human-oriented (in contrast to technology-oriented) human-computer interfaces developers have to develop sound knowledge of the structure and the representational dynamics of the cognitive system which is interacting with the computer.We show that in a first step it is necessary to study and investigate the different levels and forms of representation that are involved in the interaction processes between computers and human cognitive systems. Only if designers have achieved some understanding about these representational mechanisms, user interfaces enabling individual experiences and skill development can be designed. In this paper we review mechanisms and processes for knowledge representation on a conceptual, epistemological, and methodologieal level, and sketch some ways out of the identified dilemmas for cognitive modeling in the domain of human-computer interaction.     

Requirements development in scenario-based design

We describe and analyze the process of requirements development in scenario based design through consideration of a case study. In our project, a group of teachers and system developers initially set out to create a virtual physics laboratory. Our design work centered on the collaborative development of a series of scenarios describing current and future classroom activities. We observed classroom scenarios to assess needs and opportunities, and envisioned future scenarios to specify and analyze possible design moves. We employed claims analysis to evaluate design trade-offs implicit in these scenarios, to codify the specific advantages and disadvantages in achieving requirements. Through the course of this process, the nature of our project requirements has evolved, providing more information but also more kinds of information. We discuss the utility of managing requirements development through an evolving set of scenarios, and the generality of the scenario stages from this case study     

Development of a rapid prototyping design advice system

This paper describes the initial development of a computer based Rapid Prototyping Design Advice System. The system is intended to assist the designer or project manager, particularly those in small and medium sized companies, in planning the prototyping stage of product development. It provides the user with an efficient and user friendly development aid which uses information obtained from the user and Computer Aided Design data to recommend suitable rapid prototyping solutions.     

Generic manufacturing information systems development via template prototyping

There are a number of difficulties with software support for production management decision making in small manufacturing enterprises (SME). System requirement specification and total system cost are two major hurdles. A generic approach to the system design will enable the development costs to be spread across a group of users, while prototyping offers the potential to involve users in the system specification and design. However existing prototyping methodologies have not focused on producing generic software. The template prototyping concepts developed here, together with the derived methodology, based on object-orientated structures, contribute significantly to overcoming these difficulties. The use of the developed software in practice and as a learning tool in computer aided production management for SME environments is outlined.     

The usability engineering life cycle

A practical usability engineering process that can be incorporated into the software product development process to ensure the usability of interactive computer products is presented. It is shown that the most basic elements in the usability engineering model are empirical user testing and prototyping, combined with iterative design. Usability activities are presented for three main phases of a software project: before, during, and after product design and implementation. Some of the recommended methods are not really single steps but should be used throughout the development process     

From scenarios to code: An air traffic control case study

There has been much recent interest in synthesis algorithms that generate finite state machines from scenarios of intended system behavior. One of the uses of such algorithms is in the transition from requirements scenarios to design. Despite much theoretical work on the nature of these algorithms, there has been very little work on applying the algorithms to practical applications. In this paper, we apply the Whittle & Schumann synthesis algorithm [32] to a component of an air traffic advisory system under development at NASA Ames Research Center. We not only apply the algorithm to generate state machine designs from scenarios but also show how to generate code from the generated state machines using existing commercial code generation tools. The results demonstrate the possibility of generating application code directly from scenarios of system behavior.     

An Expansive View of Reusable Software

The present crisis in software development forces us to reconsider the fundamental ways in which programming is done. One often quoted solution is to exploit more fully the idea of reusable software. It is the purpose of this paper to examine this concept in all of its forms and to assess the current state of the art. In addition to its usual meaning of reusable code, reusability includes reusable design, various forms of specification systems. so-called application generators, and systems for prototyping. We examine each approach from the perspective of the practicing engineer, and we evaluate the work in terms of how it may ultimately improve the development process for large-scale software systems.     

Creating Interdependencies: Managing Incidents in Large Organizational Environments

In recent years, we have witnessed the emergence of large-scale centers of command and control that bring together a range of personnel from various services responsible for the management of day-to-day incidents and events. These multicenter control rooms stand in marked contrast to what Suchman termed ‘centers of coordination’ (Suchman 1997), which have typically formed the focus of much research within HCI and Computer supported co-operative work (CSCW). In this paper, we explore the practices and technical resources within one of these very large multicenter control rooms. Staff in this control room do collaborate with colleagues who are copresent, but there is little reliance on the subtle interactional practices found in earlier studies. However, one information system is critical for collaboration and managing incidents that arise: the information system that is used to record incidents. Unlike in previous settings where records were made after an incident had taken place, these records are used for the concurrent management of activities. We consider the practices through which staff assemble these records to serve the demands of different individuals, with differing responsibilities in various organizations within the control room. We consider instances of copresent collaboration and suggest that these are often to ameliorate problems with the records rather than supporting real-time colocated activities. Although staff may be copresent in these multicenter control rooms, they have different kinds of technological resources available to them, and a different ‘division of labor.’ This can undermine the integration of these resources within forms of work. We conclude by discussing the implications for our understanding of copresent work and also for the methods and approaches we can draw upon for understanding these contemporary workplaces.     

Implementing a computer aided production management system

This paper describes the design and implementation of a computer aided production management system for a wall-coverings manufacturer. The computer systems were implemented on a co-operative network of PCs and Vaxes. The software was written in NATURAL/ADABAS and GENETIK. The systems were successfully implemented and achieved immediate payoffs in reduced stock levels and better planning. A less obvious payoff came from the extended time-scale of the project which meant that the company's staff could be trained en route.