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Requirements Engineering (RE) is the process of discovering and defining user requirements for developing software systems. The early phase of this process is concerned with eliciting and analysing requirements. Modelling, the activity of constructing abstract descriptions that are amenable to communication between different stake-holders plays a critical role in requirements elicitation and analysis. However, current modelling tools are based on formal notations such as UML Diagrams and i* Diagram that do not support the use of hand-drawn diagrams or a mix of hand-drawn and computer drawn diagram to draw initial requirements models and subsequently transform the drawn models into target software models. The research presented in this thesis aims to address this problem. It aims to achieve two related objectives: 1) to develop a sketch tool, iSketch, that would enable users to draw use case diagram using either hand-drawn diagram or a mix of hand-drawn and computer drawn diagram. and 2) to support the transformation of the drawn use case diagram into initial software models represented by UML Class Diagram and UML Sequence Diagram. Central to these research objectives are the development of novel sketch recognition and model transformation techniques for iSketch. To support sketch recognition, we have developed a deep learning technique that uses colour inversion to classify and improve the recognition rate of iSketch models. To support model transformation, we have developed a semantic modelling approach that works by first translating iSketch models into intermediate Agent-Oriented Models and finally into initial software models. iSketch was evaluated in two ways. First, validation of iSketch through 2 experiments to measure the performance of iSketch in sketch recognition and model transformation using stroke labelling, and f-score metrics, respectively. In sketch recognition, iSketch achieved a recognition accuracy of 89.91% and 97.29% without and with colour inversion respectively when tested on iSketch dataset. In model transformation, iSketch achieved an f-score of 91.22% and 60.88% in generating UML Sequence and Class Diagrams respectively from iSketch models. Second, iSketch was compared with 15 related approaches. The result showed that only iSketch supports an automatic generation of initial software models from hand-drawn requirements models.

Whilst numerous studies have retrospectively reported the impact of negative user emotions, motivational problems or value clashes during software developments, few Requirements Engineering (RE) studies have considered the elicitation of users’ values, motivations or emotions (VM&Es) and there is little advice for practising analysts as to how to deal with these factors. This thesis explores the impact of users’ VM&Es within RE work. The starting point was a review of the current state of analyst practice. A literature survey considered the RE guidance available to analysts on the elicitation and understanding of ‘soft issues’ such as VM&Es. In parallel, a series of interviews with 12 industry analysts sought their views on the relevance of users’ VM&Es, the impact on requirements work, and approaches to identifying such information. This study identified behaviours adopted by experienced analysts that would be useful to promote to novice analysts, and documented the analysts’ own requirements for a method to support them in eliciting VM&Es. These findings informed the design of the Value Based Requirements Engineering (VBRE) method and website (www.vbre.org.uk), intended to support requirements analysts in identifying and considering the impact of such ‘soft factors’. Research into RE method adoption highlights the importance of industry input, so a Participatory Design (PD) approach was taken in developing VBRE, iteratively evaluating and refining the method with input from practising analysts. A series of complementary evaluations of the method are presented. An experimental study investigated the method’s utility and usability with computer science undergraduate students, whilst a set of four case studies explored adoption of the VBRE method with industry analysts. The analysts used the method during their RE work, adapting the approach according to their circumstances and levels of experience. The participants credited the method with a positive impact on their RE work and the novice analysts reported feeling more confident of their abilities to handle ‘soft issues’. The key contributions of this work are:1. An exploration of the views of practising analysts as to the relevance and impact of VM&Es within their RE work.2. Development of an analysis method and support materials to aid analysts in identifying users’ VM&Es.3. A demonstration of the utility of adopting a PD approach to the development of RE methods.4. An evaluation of the use of the method in industry, exploring the use of case studies to understand how novice and expert analysts adopt and adapt the VBRE approach. This thesis is unusual in taking a PD approach to developing a solution for a RE problem: that analysts need to understand users’ VM&Es and their impact on software projects. The VBRE method attempts to address this gap, and the positive reception given by the analysts involved in evaluation of the method indicates they see utility in the approach. Future work will focus on continuing to collaborate with industry analysts to understand their use of the VBRE method, identifying improvements to the method and website, and gathering examples of the method’s impact.

The research presented in this thesis focuses on the development of wireless, real time performance monitoring technology within the resistance training domain using a user-centred design methodology. The functionality of current performance monitoring technology and differences in monitoring ability is investigated through comparative force platform, video and accelerometer testing and analysis. Determining the complexity of resistance training exercises and whether performance variable profiles such as acceleration, velocity and power can be used to characterise lifts is also investigated. A structured user-centred design process suitable for the sporting domain is proposed and followed throughout the research to consider the collection, analysis and communication of performance data. Identifying the user requirements and developing both hardware and software to meet the requirements also forms a major part of the research. The results indicate that as the exercise complexity increases, the requirement for sophisticated technology increases. A simple tri-axial accelerometer can be used to monitor simple linear exercises at the recreational level. Gyroscope technology is required to monitor complex exercises in which rotation of the bar occurs. Force platform technology is required at the elite level to monitor the distribution of force and resultant balance throughout a lift (bilateral difference). An integrated system consisting of an Inertial Measurement Unit (both accelerometer and gyroscope technology) and a double plate force platform is required to accurately monitor performance in the resistance training domain at the elite level.

The precision of formal specifications allows us to prove program correctness. Even if formal methods are not used throughout the software project, formalisation improves our understanding of the problem. Formal specifications are amenable to automated analysis and consistency checking. However using them is challenging. Customers do not understand formal notations. Specifiers have difficulty tackling large problems. Once systems are built, formal specifications quickly become outdated during software maintenance. A method of developing formal specifications using concrete scenarios is proposed to tackle the disadvantages just mentioned. A concrete scenario describes system behaviour with successive steps. The pre- and post-states of scenario steps are expressed with actual data rather than variables. Concrete scenarios are expressed in a natural language or formal notation. They increase customer involvement in the creation of formal specifications. Scenarios may be ranked by priorities allowing specifiers to focus on a small part of the system. Formal specifications are constructed incrementally. New requirements are also captured in concrete scenarios which guide the modification of formal specifications. On one hand, concrete scenarios assist the creation and maintenance of formal specifications. On the other hand, they facilitate program correctness proofs without using conventional formal specifications. This is achieved by adding implementation details to customer scenarios. The resulting developer scenarios, encapsulating decisions of data structures and algorithms, are generalised to operation schemas. With the implementation details, the schemas written in formal notations are programs rather than specifications.

Within the field of software engineering, requirements elicitation is the activity in which stakeholder needs are understood. In large-scale software projects, requirements elicitation tends to be beset by three problems: information overload, inadequate stakeholder input, and biased prioritisation of requirements. The work described in this thesis addresses these problems using social networks and collaborative filtering. The work has developed StakeNet, a novel method that uses social networks to identify and prioritise stakeholders. Using StakeNet, the requirements engineer asks an initial list of stakeholders to recommend other stakeholders and stakeholder roles, builds a social network with stakeholders as nodes and their recommendations as links, and prioritises the stakeholders using a variety of social network measures. The work has also developed StakeRare, a novel method that uses social networks and collaborative filtering to identify and prioritise requirements. Using StakeRare, the requirements engineer asks the stakeholders identified by StakeNet to rate an initial list of requirements and suggest other requirements, recommends other relevant requirements to the stakeholders using collaborative filtering, and prioritises the requirements using the ratings and the stakeholders’ priority from StakeNet. Finally, to support the methods, this work has developed StakeSource, a novel software tool that automates the manual processes in StakeNet. StakeSource collects recommendations from stakeholders, builds the social network, and prioritises the stakeholders automatically. The methods and tool have been evaluated using real large-scale software projects. The empirical evaluation of both StakeNet and StakeRare using a real large-scale software project demonstrates that the methods identify a highly complete set of stakeholders and their requirements, and prioritise the stakeholders and their requirements accurately. These methods outperform the existing methods used in the project, and require significantly less time from the stakeholders and requirements engineers. StakeSource has been evaluated with real large-scale projects by practitioners. The tool is now used in major software projects, and organisations are adopting it. The methods, tool, and evaluation described in this thesis provide evidence that social networks and collaborative filtering can effectively support requirements elicitation in large-scale software projects.

Medical device usability directly impacts the practitioner's ability to perform their diagnostic task in an effective, efficient, and safe manner. A device with poor usability may frustrate the practitioner, increasing the worker's stress level in a high-stress work environment. In addition, a device with poor usability may facilitate operator error, increasing the patient's risk of injury. Designers of healthcare systems and devices face a unique conundrum that has been documented in the literature (Martin, Murphy, Crowe, & Norris, 2006; Martin, Norris, Murphy, & Crowe, 2007; Ward & Clarkson, 2007). Standards require the use of user research techniques, yet patient privacy standards prevent designers from observing users in context. The inability to observe users in their work environment impedes understanding the context-of-use. Since understanding context-of-use is required to ensure usability, further exploration into alternative methods for requirements gathering is needed. This study explored the storytelling as an elicitation method for medical device requirements by comparing the information elicited from nurses during requirements gathering for an infusion pump by two methods: focus groups followed by interviews (Group #1) and focus groups followed by storytelling sessions (Group #2). Results suggest further exploration of storytelling is warranted as Group #2 contributed similar quantity and breadth of information in significantly less time. Results also indicate potential support for the efficacy of storytelling within the healthcare domain as Group #2 participants contributed more distinct context-of-use information with an emphasis on the social context. Contributions of this study include a plan for mixed-method data analysis, a protocol for conducting a storytelling session, and a framework for defining requirements within the healthcare domain.