Healthcare Modelling through Role Activity Diagrams for Process-Based Information Systems Development

The aim of this paper is to introduce the socio-technical Role Activity Diagram modelling language to National Health Service (NHS) information systems requirements engineering using a process approach. Most requirements engineering in the NHS is done using data-driven methods such as data flow diagrams. Role Activity Diagrams provide not only a socio-technical method for analysing a particular systems development problem, but they also offer a process-based approach for capturing workflows and their associated information flows, and facilitate communication between analysts and users in an intuitive fashion. In particular, they elicit the important roles in a process and the interaction and collaboration required to achieve the goals of the process. The process approach has been applied in business information systems development. It is introduced here as a potential for systems development in the NHS.     

WIRES: A Methodology for Developing Workflow Applications

Workflow management systems are becoming a relevant support for a large class of business applications, and many workflow models as well as commercial products are currently available. While the large availability of tools facilitates the development and the fulfilment of customer requirements, workflow application development still requires methodological guidelines that drive the developers in the complex task of rapidly producing effective applications. In fact, it is necessary to identify and model the business processes, to design the interfaces towards existing cooperating systems, and to manage implementation aspects in an integrated way. This paper presents the WIRES methodology for developing workflow applications under a uniform modelling paradigm – UML modelling tools with some extensions – that covers all the life cycle of these applications: from conceptual analysis to implementation. High-level analysis is performed under different perspectives, including a business and an organisational perspective. Distribution, interoperability and cooperation with external information systems are considered in this early stage. A set of “workflowability” criteria is provided in order to identify which candidate processes are suited to be implemented as workflows. Non-functional requirements receive particular emphasis in that they are among the most important criteria for deciding whether workflow technology can be actually useful for implementing the business process at hand. The design phase tackles aspects of concurrency and cooperation, distributed transactions and exception handling. Reuse of component workflows, available in a repository as workflow fragments, is a distinguishing feature of the method. Implementation aspects are presented in terms of rules that guide in the selection of a commercial workflow management system suitable for supporting the designed processes, coupled with guidelines for mapping the designed workflows onto the model offered by the selected system.     

A Qualitative Scenario Approach to Managing Evolving Requirements

In this paper, we argue that information systems requirements are inherently dynamic, and that a methodology that caters for such dynamicity must enable the evaluation of requirements, as they evolve, against dynamic contexts. Moreover, information systems contexts are soft, ambiguous, and are thus mainly characterised by qualitative data. We present an analytical technique, based on the grounded theory method for developing qualitative scenarios against which statements of requirements can be evaluated.     

Display Design of Process Systems Based on Functional Modelling

The prevalent way to present information in industrial computer displays is by using piping and instrumentation diagrams. Such interfaces have sometimes resulted in difficulties for operators because they are not sufficient to fulfil their needs. A systematic way that supports interface design therefore has to be considered. In the new design framework, two questions must be answered. Firstly, a modelling method is required to describe a process system. Such a modelling method can define the information content that must be displayed in interfaces. Secondly, how to communicate this information to operators efficiently must be considered. This will provide a basis for determining the visual forms that the information should take. This study discusses interface design of human–machine systems from these two points of view. Based on other scholars’ work, a comprehensive set of functional primitives is summarised as a basis to build a functional model of process systems. A library of geometrical presentations for these primitives is then developed. To support effective interface design, the concept of ‘functional macro’ is introduced and a way to map functional model to interface display is illustrated by applying several principles. To make our ideas clear, a central heating system is taken as an example and its functional model is constructed. Based on the functional model, the information to be displayed is determined. Several functional macros are then found in the model and their corresponding displays are constructed. Finally, by using the library of geometrical presentations for functional primitives and functional macros, the display hierarchy of the central heating system is developed. Reusability of functional primitives makes it possible to use the methodology to support interface design of different process systems.     

A Framework for Integrating Non-Functional Requirements into Conceptual Models

The development of complex information systems calls for conceptual models that describe aspects beyond entities and activities. In particular, recent research has pointed out that conceptual models need to model goals, in order to capture the intentions which underlie complex situations within an organisational context. This paper focuses on one class of goals, namely non-functional requirements (NFR), which need to be captured and analysed from the very early phases of the software development process. The paper presents a framework for integrating NFRs into the ER and OO models. This framework has been validated by two case studies, one of which is very large. The results of the case studies suggest that goal modelling during early phases can lead to a more productive and complete modelling activity.       

User diversity and design representation: Towards increased effectiveness in Design for All

This paper addresses user modelling for “Design for All” in a model-based approach to Human-Computer Interaction, paying particular attention to placing user models within organisational role- and task-related contexts. After reviewing a variety of user modelling approaches, and deriving requirements for user modelling related to Design for All, the paper proposes a role-driven individualised approach. Such an approach is based on a model-based representation schema and a unifying notation that keeps the user’s models and the contextual information transparent and consistent. Individualisation is achieved by coupling symbolic model specifications with neural networking on synchronisation links between symbolic representation elements. As a result, user modelling for Design for All is achieved not by stereotypical user properties and functional roles, but by accommodating the actual users’ behaviour. Published online: 18 May 2001     

Specifications in Context: Stakeholders, Systems and Modelling of Conflict

This paper looks from an ethnographic viewpoint at the case of two information systems in a multinational engineering consultancy. It proposes using the rich findings from ethnographic analysis during requirements discovery. The paper shows how context – organisational and social – can be taken into account during an information system development process. Socio-technical approaches are holistic in nature and provide opportunities to produce information systems utilising social science insights, computer science technical competence and psychological approaches. These approaches provide fact-finding methods that are appropriate to system participants’ and organisational stakeholders’ needs.  The paper recommends a method of modelling that results in a computerised information system data model that reflects the conflicting and competing data and multiple perspectives of participants and stakeholders, and that improves interactivity and conflict management.     

The Spiral of Change Model for Coping with Changing and Ongoing Requirements

This paper is a discussion on the problem of establishing information requirements in changing and ongoing business organisations. Attempts within existing software development paradigms to cope with business change are identified and discussed, and their problems concerning business change are highlighted. The alternative spiral of change model of tailorable information systems is proposed for thinking about establishing changing and ongoing information systems requirements. It is also proposed that information should be reconceptualised as tailorable. Such a reconceptualisation would allow us to explore ways of establishing information systems requirements that cope with business change. Deferred system’s design is proposed as a form of business software design and development that can cope with business change, as well as with the contextual and situational nature of tailorable information.     

On Abstraction in Scenarios

Scenarios are ways of representing knowledge. They may take many forms, from films of real events through acted scenes to documented procedures. These forms differ in many ways, including how vivid or abstract they are, how accessible they are as specifications, and how effective they are in helping to elicit requirements. Scenarios, especially as Use Cases, are in use or proposed for many aspects of systems engineering. Understanding of the different forms scenarios may take, and then of the costs and benefits of applying these forms in practice, may be valuable.     

An Approach to Security Requirements Engineering for a High Assurance System*

Requirements specifications for high-assurance secure systems are rare in the open literature. This paper examines the development of a requirements document for a multilevel secure system that must meet stringent assurance and evaluation requirements. The system is designed to be secure, yet combines popular commercial components with specialised high-assurance ones. Functional and non-functional requirements pertinent to security are discussed. A multidimensional threat model is presented. The threat model accounts for the developmental and operational phases of system evolution and for each phase accounts for both physical and non-physical threats. We describe our team-based method for developing a requirements document and relate that process to techniques in requirements engineering. The system requirements document presented provides a calibration point for future security requirements engineering techniques intended to meet both functional and assurance goals. RID="*" ID="*"The views expressed in this paper are those of the authors and should not be construed to reflect those of their employers or the Department of Defense. This work was supported in part by the MSHN project of the DARPA/ITO Quorum programme and by the MYSEA project of the DARPA/ATO CHATS programme. Correspondence and offprint requests to: T. Levin, Department of Computer Science, Naval Postgraduate School, Monterey, CA 93943-5118, USA. Tel.: +1 831 656 2339; Fax: +1 831 656 2814; Email: levin@nps.navy.mil     

Information Systems Curricula Evaluated by a Method Engineering Framework

Method engineering (ME) deals with the selection and assembly of situation-specific methods for information systems development. In this paper we use ME with a somewhat unusual perspective, that is, an educational one. We introduce a procedure for the evaluation of information systems curricula within an ME framework. Using this approach it is possible to quantitatively characterise and compare information systems curricula, showing their relative strengths and weaknesses. As an example we evaluate three model curricula (IS’90, IS’97 and ISCC’99) and analyse their differences and similarities.     

Making Workflow Change Acceptable

Virtual professional communities are supported by network information systems composed from standard Internet tools. To satisfy the interests of all community members, a user-driven approach to requirements engineering is proposed that produces not only meaningful but also acceptable specifications. This approach is especially suited for workflow systems that support partially structured, evolving work processes. To ensure the acceptability, social norms must guide the specification process. The RENISYS specification method is introduced, which facilitates this process using composition norms as formal representations of social norms. Conceptual graph theory is used to represent four categories of knowledge definitions: type definitions, state definitions, action norms and composition norms. It is shown how the composition norms guide the legitimate user-driven specification process by analysing a case on the development of an electronic law journal.     

Engineering Requirements Through Use Cases in Complex Business Environment

The increasingly global nature of financial markets and institutions means that the collection and management of information on which decisions might be based are increasingly complex. There is a growing requirement for the integration of information flows at individual and departmental levels, and across processes and organisational boundaries. Effective information management is an important contributory factor in the efficiency of such institutions, though there are many associated problems that do not have obvious or simple answers. This paper discusses the problem of information gathering in complex business environments and considers how use cases can help to alleviate the problem using an example of a multinational organisation. Such organisations often require information systems that can support regional differences. However, management requires consistent and uniform representation of information. The example shows that use cases can be a helpful mechanism for capturing user requirements that accommodate both regional properties as well as their organisational commonalties.     

The Importance of Context in Information System Design: An Assessment of Participatory Design

This paper is predicated on requirements analysis as the Achilles heel of information systems development, and accepts that information systems often disappoint. Most design paradigms can be located within a rationalistic framework polarised by requirements analysis and system delivery. Such traditional design paradigms are seen as palliatives that prevent us moving toward more satisfying information systems. It is argued that this rationalistic framework forces us to identify, and attempt to solve, problems that are symptomatic of the approach adopted. A pluralistic framework for information system development is presented which rejects the notions of requirements analysis and system optimality. Participatory design, derived from the field of human computer interaction, is located within this framework and identified as a possible paradigm for information system development. A case study is conducted to assess the benefits of participatory design techniques and to evaluate the extent to which participatory design can overcome the failings of traditional methodologies.     

Automatically Detecting and Visualising Errors in UML Diagrams

UML has become the de facto standard for object-oriented modelling. Currently, UML comprises several different notations with no formal semantics attached to the individual diagrams or their integration, thus preventing rigorous analysis of the diagrams. Previously, we developed a formalisation framework that attaches formal semantics to a subset of UML diagrams used to model embedded systems. This paper describes automated structural and behavioural analyses applicable to UML diagrams using our formalisation framework. In addition to intra- and inter-diagram consistency checks, we discuss how simulation and model checking can be used in tandem for behavioural analysis of the UML diagrams. Our tools also visually interpret the analysis results in terms of the original UML diagrams, thereby facilitating their correction and refinement. We illustrate these capabilities through the modelling and analysis of UML diagrams for an automotive industrial case study. Correspondence and offprint requests to: Dr B. Cheng, Software Engineering and Network Systems Laboratory, Department of Computer Science and Engineering, Michigan State University, 3115 Engineering Building, East Lansing, MI 48824, USA. Tel.: +1 517 355 8344; Fax: +1 517 432 1061; Email: chengb@cse.msu.edu     

Coupling Use Cases and Class Models as a Means for Validation and Verification of Requirements Specifications

In many applications, especially from the business domain, the requirements specification mainly deals with use cases and class models. Unfortunately, these models are based on different modelling techniques and aim at different levels of abstraction, such that serious consistency and completeness problems are induced. To overcome these deficiencies, we refine activity graphs to meet the needs for a suitable modelling element for use case behaviour. The refinement in particular supports the proper coupling of use cases via activity graphs and the class model. The granularity and semantics of our approach allow for a seamless, traceable transition of use cases to the class model and for the verification of the class model against the use case model. The validation of the use case model and parts of the class model is supported as well. Experience from several applications has shown that the investment in specification, validation and verification not only pays off during system and acceptance testing but also significantly improves the quality of the final product.       

Control and data abstraction: the cornerstones of practical formal verification

In spite of the impressive progress in the development of the two main methods for formal verification of reactive systems – Symbolic Model Checking and Deductive Verification, they are still limited in their ability to handle large systems. It is generally recognized that the only way these methods can ever scale up is by the extensive use of abstraction and modularization, which break the task of verifying a large system into several smaller tasks of verifying simpler systems. In this paper, we review the two main tools of compositionality and abstraction in the framework of linear temporal logic. We illustrate the application of these two methods for the reduction of an infinite-state system into a finite-state system that can then be verified using model checking. The technical contributions contained in this paper are a full formulation of abstraction when applied to a system with both weak and strong fairness requirements and to a general temporal formula, and a presentation of a compositional framework for shared variables and its application for forming network invariants.     

Socio-Technical and Soft Approaches to Information Requirements Elicitation in the Post-Methodology Era

The contributors to this special issue focus on socio-technical and soft approaches to information requirements elicitation and systems development. They represent a growing body of research and practice in this field. This review presents an overview and analysis of the salient themes within the papers encompassing their common underlying framework, the methodologies and tools and techniques presented, the organisational situations in which they are deployed and the issues they seek to address. It will be argued in the review that the contributions to this special edition exemplify the ‘post-methodological era’ and the ‘contingency approaches’ from which it is formed.     

There’s More to Information Systems Development than Structured Approaches: Information Requirements Analysis as a Socially Mediated Process

Information systems (IS) development approaches are considered with particular reference to those aspects of the process most concerned with the determination of information requirements. The majority can be classified as adopting a unitary, objective perspective. This perspective fails to recognise the interpretative, inter-subjective nature of information and the importance of informal as well as formal data-processing systems. This paper aims to contribute to the discussion on socio-technical and soft approaches to IS development by providing a contrasting perspective on information requirements analysis as a process which is socially mediated. A framework is developed which places information requirements analysis in the context of strategic IS development. This locates social communication networks centrally in this process and raises implications for the practice of IS development, and of information requirements analysis.     

Representations in Human–Computer Systems Development

When system developers design a computer system (or other information artefact), they must inevitably make judgements as to how to abstract the domain and how to represent this abstraction in their designs. Over the years human–computer interaction, or more generally information systems design, has had a history of developing competing methods and models for both the process and products of its development. Various paradigms have been suggested, often trying to keep pace with the changing nature of the design problem; from batch processing to interactive systems to work situations and most recently to designing for household environments. It appears timely, then, to review the nature of the design problem that faces the developers of human–computer systems and to consider some of the impact that different representations and different conceptualisations may have on their activities. Green (1998) has suggested that a single model of developing human–computer systems is not desirable, instead arguing for a number of limited theories each of which provides a useful perspective. The aim of this paper is to place competing methods side by side in order to see their strengths and weaknesses more clearly. The central tenet of the paper is that different views of both the human–computer system design process and the different abstractions, or models, that are produced during the design process have varying degrees of utility for designers. It is unlikely that any single method or modelling approach will be optimal in all circumstances. Designers need to be aware of the range of views that exist and of the impact that taking a particular approach may have on the design solution.