Abstract: From the Publisher: Difficult to learn and awkward to use, today's information systems often change our activities in ways that we do not need or want. The problem lies in the software development process. In this book John Carroll shows how a pervasive but underused element of design practice, the scenario, can transform information systems design. Traditional textbook approaches manage the complexity of the design process via abstraction, treating design problems as if they were composites of puzzles. Scenario-based design uses concretization. A scenario is a concrete story about use. For example: "A person turned on a computer; the screen displayed a button labeled Start; the person used the mouse to select the button." Scenarios are a vocabulary for coordinating the central tasks of system development—understanding people's needs, envisioning new activities and technologies, designing effective systems and software, and drawing general lessons from systems as they are developed and used. Instead of designing software by listing requirements, functions, and code modules, the designer focuses first on the activities that need to be supported and then allows descriptions of those activities to drive everything else. In addition to a comprehensive discussion of the principles of scenario-based design, the book includes in-depth examples of its application.

Abstract: System-level design issues become critical as implementation technology evolves toward increasingly complex integrated circuits and the time-to-market pressure continues relentlessly. To cope with these issues, new methodologies that emphasize re-use at all levels of abstraction are a "must", and this is a major focus of our work in the Gigascale Silicon Research Center. We present some important concepts for system design that are likely to provide at least some of the gains in productivity postulated above. In particular, we focus on a method that separates parts of the design process and makes them nearly independent so that complexity could be mastered. In this domain, architecture-function co-design and communication-based design are introduced and motivated. Platforms are essential elements of this design paradigm. We define system platforms and we argue about their use and relevance. Then we present an application of the design methodology to the design of wireless systems. Finally, we present a new approach to platform-based design called modern embedded systems, compilers, architectures and languages, based on highly concurrent and software programmable architectures and associated design tools.

Abstract: Target cascading is a key challenge in the early product development stages of large complex artifacts: how to propagate the desirable top level design specifications (or targets) to appropriate specifications for the various subsystems and components in a consistent and efficient manner. Consistency means that all parts of the designed system should work well together, while efficiency means that the process itself should avoid iterations at later stages, which are costly in time and resources. In the present article target cascading is formalized by a process modeled as a multilevel optimal design problem. Design targets are cascaded down to lower levels using partitioning of the original problem into a hierarchical set of subproblems. For each design problem at a given level, an optimisation problem is formulated to minimize deviations from the propagated targets and thus achieve intersystem compatibility. A coordination strategy links all subproblem decisions so that the overall system performance targets are met. The process is illustrated with an explicit analytical problem and a simple automotive chassis design model that demonstrates how the process can be applied in practice.

Abstract: A wide range of formal methods have been devised and used for idea generation in conceptual design. Experimental evidence is needed to support claims regarding the effectiveness of these methods in promoting idea generation in engineering design. Towards that goal this paper presents a set of effectiveness metrics experimental methods, data collection and analysis techniques. Statistically based Design of Experiments (DOE) principles were used in developing the guidelines. Four classes of operating variables were considered to characterize the design problem and the environment. The effectiveness metrics proposed are based on outcome and consists of the quantity, quality, novelty, and variety of ideas generated. Two experimental approaches have been developed. In the Direct Method, the influence of the type of design problem and various parameters related to the procedure of an idea generation method is measured by using the method in its entirety. In the Indirect Method, each idea generation method is decomposed into key components and its overall effectiveness is predicted by experimentally studying the effectiveness of its components and their mutual interactions.

Abstract: This paper provides a survey on recent research in the area of design rationale. The study of design rationale spans a number of diverse disciplines, touching on concepts from research communities in mechanical design, software engineering, artificial intelligence, civil engineering, computer-supported cooperative work, and human-factors and human-computer interaction research. We focus this survey on prototype design rationale systems for these application domains, and put forward several major criteria with which to describe and classify design rationale systems, including argumentation-based, descriptive, process-based approaches. Further, we attempt to abstract the place of systems and tools for design rationale capture and retrieval in the context of contemporary knowledge-based engineering and Computer-Aided Design (CAD) tools. This survey is structured around classes of fundamentally different approaches, their representation schema, their capture methods and retrieval techniques. A number of recent design rationale systems, including JANUS, COMET, ADD. REMAP, HOS, PHIDIAS, DRIVE and IBIS are analysed. We conclude with an assessment of current state-of-the-art and a discussion of critical open research issues.

Abstract: The authors were all involved in the ‘seminal’ Utopia project, 1981-85, where Co-operative Design methodology, involving users very early in the design process, had an early development and application in the use of computers. One strong goal was to ‘give the end users a voice’ in design and development of computer support in work places, thus enhancing the quality of the resulting system. The ‘secondary result’ of Utopia, the methodology, with ingredients such as low-tech prototyping, early design sessions with users etc, has had great impact on IT design in general. This is the case not only where the methods are a main ingredient as in Co-operative Design and in Participatory Design, but also as part of now common practices in HCI and in CSCW in general and in later methodologies such as Consensus Participation, Contextual Design and Co-operative Inquiry. Thus the obvious idea to involve the users as early as possible in systems and interface design, using low and high tech prototypes, has become a standard to which most developers pay at least lip service. That it is not necessarily followed in practise is usually because of time constraints and lack of insight rather than ill-will, but there are also inherent difficulties. In Utopia and in further Co-operative Design practise we have met important concerns not taken into account in the original Utopia work. In our 20-year practical experience from several design and development projects we have gained insight and found methods to deal with these concerns, not always solving but at least relieving the problems. Utopia

Abstract: This paper presents an approach wherein product design is viewed as a selection process with two main stages: design alternative generation and design alternative evaluation, The focus of this paper is mainly on a design alternative evaluation model in that designer's preferences, customers' preferences, and market competition are accounted for in order to select the best possible design. In the model, uncertainties in the product design life, market size and its yearly change, cost and its yearly change, price, and discount rate are considered. Product design selection of a cordless screwdriver is used as a demonstration example. However, the emphasis in the example is on the approach, and not on the details per se.

Abstract: Current planning practice takes little account of the interdisciplinary, iterative nature of the building design process. This leads to a compromised design process containing inevitable cycles of rework together with associated time and cost penalties in both design and construction. The analytical design planning technique (ADePT) is a planning methodology which helps to overcome these difficulties. The central part of ADePT is a dependency structure matrix (DSM). This paper describes DSM techniques and a tool developed to optimize the design process.

Abstract: Due to the highly complex and informal data that has to be managed in the conceptual design this early design phase still lacks of suitable computer support. Furthermore, existing approaches towards a computer aided conceptual design are insufficiently integrated with the downstream applications of the product development process. The paper therefore introduces an approach towards a feature-based integrated product model that incorporates a feature-based representation scheme for capturing product semantics handled in the conceptual design phase and links early design with part and assembly modelling.

Abstract: Validation of engineering research is typically anchored in the scientific inquiry tradition that is based primarily on logical induction and / or deduction. Since much engineering research is based on mathematical modeling, this kind of validation has worked - and still works - very well. There are, however, other areas of engineering research that rely on subjective statements as well as mathematical modeling, which makes this type of validation problematic. One such area is that of design methods within the field of engineering design. In this paper, we explore the question of how one validates design research in general, and design methods in particular. Being anchored in the scientific inquiry tradition, research validation is strongly tied to a fundamental problem addressed in epistemology, namely, what is scientific knowledge and how is new knowledge confirmed? Thus, we first look to epistemology for answers to why an approach solely based on 'formal, rigorous and quantifiable' validation constitutes a problem, and for an augmented approach to research validation. We then propose the 'Validation Square' which we validate by testing its internal consistency based on logic in addition to testing its external relevance based on its usefulness with respect to a purpose. We recognize that no one has the complete answer to the question we pose. To help us converge on an answer to these questions we "think aloud" and invite you to join us in doing the same. It is our hope that in so doing we, the members of this design research community, will all be the richer for it .

Abstract: Rework that is experienced in construction projects is often caused by errors made during the design process. Factors that contribute to design errors are identified and used to design and develop a systems dynamics model, which is used to simulate a number of practical scenarios that can be used to reduce design errors and rework. The model presented in this paper can enable design and project managers to understand better the process of design documentation and how design errors occur in construction projects.

Abstract: The paper introduces the concept of an Interactive Evolutionary Design System (IEDS) that supports the engineering designer during the conceptual/preliminary stages of the design process. Requirement during these early stages relates primarily to design search and exploration across a poorly defined space as the designer's knowledge base concerning the problem area develops. Multiobjective satisfaction plays a major role, and objectives are likely to be ill-defined and their relative importance uncertain. Interactive evolutionary search and exploration provides information to the design team that contributes directly to their overall understanding of the problem domain in terms of relevant objectives, constraints, and variable ranges. This paper describes the development of certain elements within an interactive evolutionary conceptual design environment that allows off-line processing of such information leading to a redefinition of the design space. Such redefinition may refer to the inclusion or removal of objectives, changes concerning their relative importance, or the reduction of variable ranges as a better understanding of objective sensitivity is established. The emphasis, therefore, moves from a multiobjective optimization over a preset number of generations to a relatively continuous interactive evolutionary search that results in the optimal definition of both the variable and objective space relating to the design problem at hand. The paper describes those elements of the IEDS relating to such multiobjective information gathering and subsequent design space redefinition.

Abstract: A new methodology for seismic design is proposed based on structural optimization with performance-based constraints. Performance-based criteria are introduced for the seismic design of new buildings. These criteria are derived from the National Guidelines for Seismic Rehabilitation of Buildings (Reference [19], Federal Emergency Management Agency (FEMA), ‘NHERP Guidelines for seismic rehabilitation of buildings’, Report Nos 273 and 274, Washington, DC, 1997) for retrofitting existing structures. The proposed design methodology takes into account the non-linear behaviour of the structure. The goal is to incorporate in the design the actual performance levels of the structure, i.e. how much reserve capacity the structure has in an earthquake of a given magnitude. The optimal design of the structure minimizes the structural cost subjected to performance constraints on plastic rotations of beams and columns, as well as behavioural constraints for reinforced concrete frames. Uncertainties in the structural period and in the earthquake excitation are taken into account using convex models. The optimization routine incorporates a non-linear analysis program and the procedure is automated. The proposed methodology leads to a structural design for which the levels of reliability (performance levels) are assumed to be quantifiable. Furthermore, the entire behaviour of the structure well into the non-linear range is investigated in the design process. Copyright © 2000 John Wiley & Sons, Ltd.

Abstract: The construction of a large, complex belief network model, like any major system development effort, requires a structured process to manage system design and development. This paper describes a belief network engineering process based on the spiral system lifecycle model. The problem of specifying numerical probability distributions for random variables in a belief network is best treated not in isolation, but within the broader context of the system development effort as a whole. Because structural assumptions determine which numerical probabilities or parameter values need to be specified, there is an interaction between specification of structure and parameters. Evaluation of successive prototypes serves to refine system requirements, ensure that modeling and elicitation effort are focused productively, and prioritize directions of enhancement and improvement for future prototypes. Explicit representation of semantic information associated with probability assessments facilitates tracing of the rationale for modeling decisions, as well as supporting maintenance and enhancement of the knowledge base.

Abstract: Advances in computational technology and in physics-based modeling are making large-scale, detailed simulations of complex systems possible within the design environment. For example, the integration of computing, communications, and aerodynamics has reduced the time required to analyze major propulsion system components from days and weeks to minutes and hours. This breakthrough has enabled the detailed simulation of major propulsion system components to become a routine part of designing systems, providing the designer with critical information about the components early in the design process. This paper describes the development of the numerical propulsion system simulation (NPSS), a modular and extensible framework for the integration of multicomponent and multidisciplinary analysis tools using geographically distributed resources such as computing platforms, data bases, and people. The analysis is currently focused on large-scale modeling of complete aircraft engines. This will provide the product developer with a "virtual wind tunnel" that will reduce the number of hardware builds and tests required during the development of advanced aerospace propulsion systems.

Abstract: Analysis plays a significant role during product design. Thanks to computational tools; it contributes highly in product optimisation while decreasing design cost and time. For analysis applications, the adaptation of the product geometry is required and consists of producing an idealised model out of a product solid one. This paper presents a form of features based tool to aid the integration of analysis during the design process. It allows producing an analysis model out of a part solid model. This tool is based on a morphological analysis of the solid model followed by a two-phase process: simplification and idealisation. The tool provides an easy way to make computer-aided design model modifications implied by the analysis results; thanks to features parameterisation and a reconstruction process. Both allow us to create a solid model on the basis of the idealised one, by using parameterised reconstruction operators.

Abstract: Preface. Part 1: Design Theory. Designing a font to test a theory T. Smithers. The role of multicriteria problem solving in design L. Mandow, J.L.P. De La Cruz. Limited computation, unlimited design J.-P. Protzen, et al. Part 2: Knowledge Modeling. Towards an ontological framework for knowledge-based design systems F. Varejao, et al. Knowledge modeling in design - the MOKA framework R. Klein. Expressing regulatory design knowledge for critiquing intelligent design assistants M. Ursu, P. Hammond. Part 3: Knowledge Management for Design. Towards a systematic repository of knowledge about managing collaborative design conflicts M. Klein. Managing knowledge in dispersed design companies facilitating context-driven design support through multiple perspectives P.A. Rodgers, et al. An integrated development environment for the design and maintenance of large configuration knowledge bases A. Felfernig, et al. Part 4: Shapes in Design. Shape grammer-based expert systems for engineering design M. Agarwal, J. Cagan. Categorisation of shapes using shape features S.-H. Park, J.S. Gero. Representations from generative systems A. Koutamanis. Part 5: Evolutionary Systems in Design. Interactive evolutionary conceptual design systems I. Parmee, et al. Fully automated design and manufacture of real machines H. Lipson, J.B. Pollack. Evolutionary structured planning C. Bezerra, C.L. Owen. Part 6: Process-Based Reasoning in Design. Structural engineering support through constraint satisfaction E. Gelle, et al. Signposting for design process improvement J. Clarkson, et al. Building design support by soft computing O.Ciftcioglu, et al. Part 7: Case-Based Reasoning in Design. Design case retrieval by generioc representations H.H. Achten. Characterising evolutionary design case adaption A. Gomez de Silva Garza, M.L. Maher. Exposures to examples A. Heylighen, I.M. Verstunen. Part 8: Learning in Design. Design heuristics extraction P. Matthews, et al. Evaluating a model of learning in design using protocol analysis S.K. Sim, A.H.B. Duffy. Discovery of design methodologies C. Shakeri, et al. Part 9: Exploration and Generation in Design. A framework for concept generation and exploration Y.-C. Liu, et al. Erasure in design space exploration R. Woodbury, et al. A design representation to support automated design generation J. Heisserman, et al. Part 10: Context in Design. Reminding and context in design C. Charlton, K. Wallace. Computational situated learning in design R. Reffat, J.S. Gero. Reasoning with design rationale J. Burge, D.C. Brown. Part 11: Agent-Based Design Systems. Deliberate evolution in multi-agent systems F.M.T. Brazier, et al. Expectation formation in multi-agent systems D.L. Grecu, D.C. Brown. Development of an intelligent agent for the design of local area networks H. Rezazad, G. Tecuci. Meaning mediated mechanism: A prototype for constructing and negotiating meaning in collaborative design J. Haymaker, et al. Contact Author Electronic Addresses. Author Index.

Abstract: The description of a comprehensive design methodology for switched reluctance machines (SRMs) is reported here The magnetic properties of the iron, the number of phases and the number of poles per phase all have a nonlinear effect on an SRM's performance These effects, along with design ratios, the sizing of the machine envelope and internal dimensions, make the machine design an intensive effort Maximization of torque density, power output, efficiency, speed range and first critical speed and minimization of torque ripple, temperature rise, acoustic noise and overall cost are among the many design objectives and critical issues that must be addressed during the design process A design methodology that maximizes the desired features and minimizes the unwanted effects is presented here Static and dynamic system level simulations and finite element analysis (FEA) have been carried out for a 4-phase, 8/6, 10 kW SRM as a design example to support the efficacy of the proposed design procedure

Abstract: Design Rationale (DR) consists of the decisions made during the design process and the reasons behind them. Because it offers more than just a “snapshot” of the final design decisions, DR is invaluable as an aid for revising, maintaining, documenting, evaluating, and learning the design. Much work has been performed on how DR can be captured and represented but not as much on how it can be used. In this paper, we investigate the use of DR by building InfoRat, a system that inferences over a design’s rationale in order to detect inconsistencies and to assess the impact of changes.

Abstract: Designing Groupware systems requires methods and tools that cover all aspects of Groupware systems. We present a method that utilizes known theoretical insights and makes them usable in practice. In our method, the design of Groupware systems is driven by an extensive task analysis followed by structured design and iterative evaluation using usability criteria. Using a combination of multiple complementary representations and techniques, a wide range of aspects of Groupware design is covered. The method is built on our experiences and is used in practice by several companies and educational institutes in Europe. We define the design process, the models needed and the tools that support the design process.

Abstract: With the increasing availability of computational power, optimization is becoming a credible and viable option when designing complex multidisciplinary systems. Computational optimization generally involves three distinct phases: 1) model the physical system in terms of design parameters and design metrics, 2 ) form an aggregate objective function in terms of the design metrics, and 3 ) minimize the aggregate objective function using an optimization code. Robust analytical and computational tools are available to perform the e rst and third phases. The analytical tools available for constructing the objective function in phase two are remarkably simplistic and generally involve dife cult-to-obtain weights. Because the optimum solution is only as effective as the aggregate objective function, any dee ciency in the formation of the latter signie cantly impacts the ultimate outcome. The multiobjective design optimization process is examined from the perspective of constructing objective functions. We expose the shortcomings of weight-based methods using analytical and numerical means. Through analytical, graphical, and computational means, we show how the physical programming approach entirely circumvents the reliance on weight, thereby resulting in a new method of practical and general applicability.

Abstract: This paper has two objectives: 1) to define, describe, and discuss integrated programs and their advantages with regard to student and faculty outcomes, as well as student retention; and 2) to describe a design process used to successfully develop and deploy an integrated first year curriculum. This paper details the results of the design process and the content of the first year integrated program implemented by the College of Engineering at Texas A&M University. The curriculum integrates the first year components of calculus, chemistry, engineering graphics, English, physics, and problem solving.