A sensor network often consists of a large number of sensing devices of different types. Upon deployment in the field, these sensing devices form an ad hoc network using wireless links or cables to communicate with each other. Sensor networks are increasingly used to support emergency responders in the field usually requiring many sensing tasks to be supported at the same time. By a sensing task we mean any job that requires some amount of sensing resources to be accomplished such as localizing persons in need of help or detecting an event. Tasks might share the usage of a sensor, but more often compete to exclusively control it because of the limited number of sensors and overlapping needs with other tasks. Sensors are in fact scarce and in high demand. In such cases, it might not be possible to satisfy the requirements of all tasks using available sensors. Therefore, the fundamental question to answer is: “Which sensor should be allocated to which task?", which summarizes the Multi-Sensor Task Allocation (MSTA) problem. We focus on a particular MSTA instance where the environment does not provide enough information to plan for future allocations constraining us to perform instantaneous allocation. We look at this problem in both static setting, where all task requests from emergency responders arrive at once, and dynamic setting, where tasks arrive and depart over time. We provide novel solutions based on centralized and distributed approaches. We evaluate their performance using mainly simulations on randomly generated problem instances; moreover, for the dynamic setting, we consider also feasibility of deploying part of the distributed allocation system on user mobile devices. Our solutions scale well with different number of task requests and manage to improve the utility of the network, prioritizing the most important tasks.

Modern healthcare has moved to a focus on providing patient centric care rather than disease centred care. This new approach is provided by a unique care team which is formed to treat a patient. At the start of the treatment, the care team decide on the treatment pathway for the patient. This is a series of treatment stages where at the end of each stage, the care team use the patient’s current condition to decide whether the treatment moves to the next stage, continues in the treatment stage, or moves to an unanticipated stage. The initial treatment pathway for each patient is based on the clinical guidelines in an Integrated Care Pathway (ICP) [1] modified to suit the patient state. This research mapped a patient ICP decided by the healthcare providers into a Workflow Management System (WFMS) [2]. The clinical guidelines reflect the patient-centric flow to create an IT system supporting the care team. In the initial stage of the research the IT development team at Velindre Hospital identified that team communication and care coordination were obstacles hindering the implementation of a patient-centric delivery model. This was investigated to determine the causes, which were identified as difficulty in accessing the medical information held in dispersed legacy systems. Moreover, a major constraint in the domain is the need to keep legacy systems in operation and so there is a need to investigate approaches to enhance their functionalities. These information systems cannot be changed across all healthcare organisations and their complete autonomy needs to be retained as they are in constant use at the sites. Using workflow technology, an independent application representing an ICP was implemented. This was used to construct an independent layer in the software architecture to interact with legacy Clinical Information Systems (CISs) and so evolve their offered functionalities to support the teams. This was used to build a Virtual Organisation (VO) [3, 4] around a patient which facilitates patient-centric care. Moreover, the VO virtually integrates the data from legacy systems and ensures its availability (as needed) at the different treatment stages along the care pathway. Implications of the proposal include: formalising the treatment process, filtering and gathering the patient’s information, ensuring care continuity, and pro-acting to change. Evaluation of the proposal involved three stages; First, usefulness evaluation by the healthcare providers representing the users; Second, setup evaluation by developers of CISs; and Finally, technical evaluation by the community of the technology. The evaluation proved; the healthcare providers’ need for an adaptive and a proactive system, the possibility of adopting the proposed system, and the novelty and innovation of the proposed approach. The research proposes a patient-centric system achieved by creating a version of an ICP in the system for each patient. It also provides focussed support for team communication and care coordination, by identifying the treatment stages and providing the care team requirements at each stage. It utilises the data within the legacy system to be proactive. Moreover, it makes these required data for the actions available from the running legacy system which is required for patient-centred care. In the future the worth could be extended by mapping other ICPs into the system. This work has been published in four full papers. It found acceptance in the health informatics community [5, 6, 7] as well as the BPM community [8, 9]. It is also the winner of the 2011 “Global Award of Excellence in Adaptive Case Management (ACM)” in “Medical and Healthcare” [10] of the Workflow Management Coalition (WFMC) [11].

Traditionally, Vehicle Routing Problems (VRPs) are modelled with fixed traversal times. The amount of time it takes to drive from one end of a road to the other is unchanged throughout the day. Nearly always, the reality of the situation that is being modelled is very different, with road speeds varying heavily, especially with “rush hour" traffic. Modelling VRPs with time varying congestion means that even slight changes early in a vehicle tour can have major knock-on effects that are hard to predict. Recalculating the total traversal time of vehicles whenever their tours are changed drastically increases metaheuristic calculation times compared to non-time varying models. In this thesis we use a simple technique of calculating the localised change and inferring the global effects resulting from neighbourhood moves. Only if the localised change suggests that the global result is satisfactory do we then calculate the actual global result. Inevitably using these estimates does not give as accurate results as always calculating the changes, but we aim to show that the loss of solution quality is overshadowed by the significant savings in calculation time. We present a series of experiments comparing simple metaheuristics with and without using estimates and show consistent savings in calculation time whenever estimates are used compared to when they are not. These savings shown to increase as the size of the problem (in terms of the number of customers) increases. In addition to synthetic problems, we also present a problem based on real world vehicle traversal times and show that our estimates prove just as accurate, if not more so, at retaining solution quality as the synthetic methods. Lastly, we briefly discuss further methods of solving VRPs that could also benefit from our work here.

This thesis sets out to answer three simple questions: What tools are available for novice programmers to program GUIs? Are those tools fulfilling their role? Can anything be done to make better tools? Despite being simple questions, the answers are not so easily constructed. In answering the first question, it was necessary to examine the range of tools available and decide upon criteria which could be used to identify tools aimed specifically at the novice programmer (there being no currently agreed criteria for their identification). Having identified these tools, it was then necessary to construct a framework within which they could be sensibly compared. The answering of the second question required an investigation of what were the successful features of current tools and which features were less successful. Success or failure of given features was determined by research in both programming language design and studies of programmer satisfaction. Having discovered what should be retained and discarded from current systems, the answering of the third question required the construction of new systems through blending elements from visual languages, program editors and fourth generation languages. These final prototypes illustrate a new way of thinking about and constructing the next generation of GUI programming languages for the novice.

Information Systems for complex situations often fail to adequately deliver quality and suitability. One reason for this failure is an inability to identify comprehensive user requirements. Seldom do all stakeholders, especially those „invisible‟ or „back room‟ system users, have a voice when systems are designed. If this is a global problem then it may impact on both the public and private sectors in terms of their ability to perform, produce and stay competitive. To improve upon this, system designers use rich pictures as a diagrammatic means of identifying differing world views with the aim of creating shared understanding of the organisation. Rich pictures have predominantly been used as freeform, unstructured tools with no commonly agreed syntax. This research has collated, analysed and documented a substantial collection of rich pictures into a single dataset. Attention has been focussed on three main research areas; how the rich picture is facilitated, how the rich picture is constructed and how to interpret the resultant pictures. This research highlights the importance of the rich picture tool and argues the value of adding levels of structure, in certain cases. It is shown that there are considerable benefits for both the interpreter and the creator by providing a pre-drawing session, a common key of symbols and a framework for icon understanding. In conclusion, it is suggested that there is some evidence that a framework which aims to support the process of the rich picture and aid interpretation is valuable.

This work contributes to knowledge in the field of semiconductor system architectures, circuit design and implementation, and communications protocols. The work starts by describing the challenges of interfacing legacy analogue subscriber loops to an electronic circuit contained within the Central Office (Telephone Exchange) building. It then moves on to describe the globalisation of the telecom network, the demand for software programmable devices to enable system customisation cost effectively, and the creation of circuit and system blocks to realise this. The work culminates in the application challenges of developing a wireless RF front end, including antenna, for an Ultra Wideband communications systems applications. This thesis illustrates how higher levels of integration over the period of 1981 to 2010 have influenced the realisation of complex system level products, particularly analogue signal processing capabilities for communications applications. There have been many publications illustrating the impact of technology advancement from an economic or technology perspective. The thesis shows how technology advancement has impacted the physical realisation of semiconductor products over the period, at system, circuit, and physical implementation levels.

The methods of Scott-Strachey semantics are applied to the problem of writing programs for parallel computers, using serial languages such as are in common use, with compilers which attempt to discover and exploit potential parallelism in independent sections of program. A mathematical model of a parallel computer is first developed in detail, and in chapters 1 and 2 three basic conditions are derived which together ensure determinacy of operation in a parallel machine, first in purely semantic terms, then in a form more related to the syntactic structure of a language. The remaining chapters apply these basic conditions to three actual languages, showing how the conditions can be reduced to purely syntactic (hence compiler evaluable) tests. Chapter 3 uses a very simple language to introduce the techniques required. Chapter 4 adds procedures, with all the complexity they involve. Chapter 5 considers the rather more fruitful area of arrays and loops. The result, in all but the most trivial cases, is a rather complicated set of conditions which, while they produce the desired effect, suggest that today's commonly used languages are not the most suitable method of exploiting parallel computers.

This thesis asserts that modern developments in technology have not been used as extensively as they could to aid blind people in their learning objectives. The same could also be said of many aspects of other areas of their lives. In particular in many countries blind students are discouraged from learning mathematics because of the intrinsically visual nature of many of the topics and particularly geometry. For many young people mathematics is also not a subject that is easily or willingly tackled. The research presented here has thus sort to answer whether a playful haptic environment could be developed which would be attractive to blind users to learn and interact with geometric concepts. In the study a software tool using a haptic interface was developed with certain playful characteristics. The environment developed sought to give the blind users practice in interacting with three dimensional geometric shapes and the investigation of the size of these shapes and their cross-section. The playful elements were enhanced by adding elements of competition such as scores and time limits which promote competition between the users. The tests have shown that blind users can easily use the system to learn about three dimensional shapes and that practice increases their confidence in recognising shape and size of these objects.

Over last years, the diffeomorphic image registration algorithms have been successfully introduced into the field of the medical image analysis. At the same time, the particular usability of these techniques, in majority derived from the solid mathematical background, has been only quantitatively explored for the limited applications such as longitudinal studies on treatment quality, or diseases progression. The thesis considers the deformable image registration algorithms, seeking out those that maintain the medical correctness of the estimated dense deformation fields in terms of the preservation of the object and its neighbourhood topology, offer the reasonable computational complexity to satisfy time restrictions coming from the potential applications, and are able to cope with low quality data typically encountered in Adaptive Radiotherapy (ART). The research has led to the main emphasis being laid on the diffeomorphic image registration to achieve one-to-one mapping between images. This involves introduction of the log-domain parameterisation of the deformation field by its approximation via a stationary velocity field. A quantitative and qualitative examination of existing and newly proposed algorithms for pairwise deformable image registration presented in this thesis, shows that the log-Euclidean parameterisation can be successfully utilised in the biomedical applications. Although algorithms utilising the log-domain parameterisation have theoretical justification for maintaining diffeomorphism, in general, the deformation fields produced by them have similar properties as these estimated by classical methods. Having this in mind, the best compromise in terms of the quality of the deformation fields has been found for the consistent image registration framework. The experimental results suggest also that the image registration with the symmetrical warping of the input images outperforms the classical approaches, and simultaneously can be easily introduced to most known algorithms. Furthermore, the log-domain implicit group-wise image registration is proposed. By linking the various sets of images related to the different subjects, the proposed image registration approach establishes a common subject space and between-subject correspondences therein. Although the correspondences between groups of images can be found by performing the classic image registration, the reference image selection (not required in the proposed implementation), may lead to a biased mean image being estimated and the corresponding common subject space not adequate to represent the general properties of the data sets. The approaches to diffeomorphic image registration have been also utilised as the principal elements for estimating the movements of the organs in the pelvic area based on the dense deformation field prediction system driven by the partial information coming from the specific type of the measurements parameterised using the implicit surface representation, and recognising facial expressions where the stationary velocity fields are used as the facial expression descriptors. Both applications have been extensively evaluated based on the real representative data sets of three-dimensional volumes and two-dimensional images, and the obtained results indicate the practical usability of the proposed techniques.

Thousands of websites providing an array of diversified online services have been the crucial factor for popularising the Internet around the world during last 15 years. The current model of accessing the majority of those services requires users to register with a Service Provider - an administrative body that offers and provides online services. The registration procedure involves users providing a number of pieces of data about themselves which are then stored at the provider. This data provides a digital image of the user and is commonly known as the Identity of the user in that provider. To access different online services, users register at different providers and ultimately end up with a number of scattered identities which become increasingly difficult to manage. It is one of the major problems of the current setting of online services. What is even worse is that users have less control over the data stored in these providers and have no knowledge how their data is treated by providers. The concept of Identity Management has been introduced to help users facilitate the management of their identities in a user-friendly, secure and privacy-friendly way and thus, to tackle the stated problems. There exists a number of Identity Management models and systems, unfortunately, none of them has played a pivotal role in tackling the problems effectively and comprehensively. Simultaneously, we have experienced another trend expanding at a remarkable rate: the consumption and the usage of smart mobile devices. These mobile devices are not only growing in numbers but also in capability and capacity in terms of processing power and memory. Most are equipped with powerful hardware and highly-dynamic mobile operating systems offering touch-sensitive intuitive user-interfaces. In many ways, these mobile devices have become an integrated part of our day-to-day life and accompany us everywhere we go. The capability, portability and ubiquitous presence of such mobile devices lead to the core objective of this research: the investigation of how such mobile devices can be used to overcome the limitations of the current Identity Management Systems as well as to provide innovative online services. In short, this research investigates the need for a novel Identity Management System and the role the current generation of smart mobile devices can play in realising such a system. In this research it has been found that there exist different inconsistent notions of many central topics in Identity Management which are mostly defined in textual forms. To tackle this problem, a comprehensive mathematical model of Identity and Identity Management has been developed. The model has been used to analyse several phenomenons of Identity Management and to characterise different Identity Management models. Next, three popular Identity Management Systems have been compared using a taxonomy of requirements to identify the strength and weakness of each system. One of the major findings is that how different privacy requirements are satisfied in these systems is not standardised and depends on a specific implementation. Many systems even do not satisfy many of those requirements which can drastically affect the privacy of a user. To tackle the identified problems, the concept of a novel Identity Management System, called User-controlled Identity Management System, has been proposed. This system offers better privacy and allows users to exert more control over their data from a central location using a novel type of provider, called Portable Personal Identity Provider, hosted inside a smart mobile device of the user. It has been analysed how the proposed system can tackle the stated problems effectively and how it opens up new doors of opportunities for online services. In addition, it has been investigated how contextual information such as a location can be utilised to provide online services using the proposed provider. One problem in the existing Identity Management Systems is that providers cannot provide any contextual information such as the location of a user. Hosting a provider in a mobile device allows it to access different sensors of the device, retrieve contextual information from them and then to provide such information. A framework has been proposed to harness this capability in order to offer innovative services. Another major issue of the current Identity Management Systems is the lack of an effective mechanism to combine attributes from multiple providers. To overcome this problem, an architecture has been proposed and it has been discussed how this architecture can be utilised to offer innovative services. Furthermore, it has been analysed how the privacy of a user can be improved using the proposed provider while accessing such services. Realising these proposals require that several technical barriers are overcome. For each proposal, these barriers have been identified and addressed appropriately along with the respective proof of concept prototype implementation. These prototypes have been utilised to illustrate the applicability of the proposals using different use-cases. Furthermore, different functional, security and privacy requirements suitable for each proposal have been formulated and it has been analysed how the design choices and implementations have satisfied these requirements. Also, no discussion in Identity Management can be complete without analysing the underlying trust assumptions. Therefore, different trust issues have been explored in greater details throughout the thesis.