A language and toolkit for the specification, execution and monitoring of dependable distributed applications

PhD ThesisThis thesis addresses the problem of specifying the composition of distributed applications out of existing applications, possibly legacy ones. With the automation of business processes on the increase, more and more applications of this kind are being constructed. The resulting applications can be quite complex, usually long-lived and are executed in a heterogeneous environment. In a distributed environment, long-lived activities need support for fault tolerance and dynamic reconfiguration. Indeed, it is likely that the environment where they are run will change (nodes may fail, services may be moved elsewhere or withdrawn) during their execution and the specification will have to be modified. There is also a need for modularity, scalability and openness. However, most of the existing systems only consider part of these requirements. A new area of research, called workflow management has been trying to address these issues. This work first looks at what needs to be addressed to support the specification and execution of these new applications in a heterogeneous, distributed environment. A co- ordination language (scripting language) is developed that fulfils the requirements of specifying the composition and inter-dependencies of distributed applications with the properties of dynamic reconfiguration, fault tolerance, modularity, scalability and openness. The architecture of the overall workflow system and its implementation are then presented. The system has been implemented as a set of CORBA services and the execution environment is built using a transactional workflow management system. Next, the thesis describes the design of a toolkit to specify, execute and monitor distributed applications. The design of the co-ordination language and the toolkit represents the main contribution of the thesis.UK Engineering and Physical Sciences Research Council, CaberNet, Northern Telecom (Nortel)

Virtually connected, practically mobile

This is the post-print version of the Chapter. The official published version can be accessed from the links below - Copyright @ 2006 SpringerThis chapter addresses a central issue in studies of mobile work and mobile technology – what is the work of mobile workers, and how do they use the resources that they have to undertake this work (i.e. the work they have to do in order to do their work)? In contrast to many of the other papers in this collection, the objective of this chapter is to examine individual mobile work, and not teamwork and co-operation other than where it impacts on the work of individuals. We present data from a study of mobile workers, examining a range of mobile workers to produce a rich picture of their work. Our analysis reveals insights into how mobile workers mix their mobility with their work, home and social lives, their use of mobile technology, the problems – technological and otherwise – inherent in being mobile, and the strategies that they use to manage their work, time, other resources and availability. Our findings demonstrate important issues in understanding mobile work, including the maintenance of communities of practice, the role and management of interpersonal awareness and co-ordination, how environmental resources affect activity, the impact of mobility on family/social relationships and the crossover between the mobile workers’ private and working lives, how preplanning is employed prior to travel, and how mobile workers perform activity multitasking, for example through making use of ‘dead time’. Finally, we turn to the implications of this data for the design and deployment of mobile virtual work (MVW) technologies for individuals and a broader organisational context

Integration and continuity of primary care: polyclinics and alternatives - a patient-centred analysis of how organisation constrains care co-ordination

Background An ageing population, the increasing specialisation of clinical services and diverse health-care provider ownership make the co-ordination and continuity of complex care increasingly problematic. The way in which the provision of complex health care is co-ordinated produces – or fails to produce – six forms of continuity of care (cross-sectional, longitudinal, flexible, access, informational and relational). Care co-ordination is accomplished by a combination of activities by patients themselves; provider organisations; care networks co-ordinating the separate provider organisations; and overall health-system governance. This research examines how far organisational integration might promote care co-ordination at the clinical level. Objectives To examine (1) what differences the organisational integration of primary care makes, compared with network governance, to horizontal and vertical co-ordination of care; (2) what difference provider ownership (corporate, partnership, public) makes; (3) how much scope either structure allows for managerial discretion and ‘performance’; (4) differences between networked and hierarchical governance regarding the continuity and integration of primary care; and (5) the implications of the above for managerial practice in primary care. Methods Multiple-methods design combining (1) the assembly of an analytic framework by non-systematic review; (2) a framework analysis of patients’ experiences of the continuities of care; (3) a systematic comparison of organisational case studies made in the same study sites; (4) a cross-country comparison of care co-ordination mechanisms found in our NHS study sites with those in publicly owned and managed Swedish polyclinics; and (5) the analysis and synthesis of data using an ‘inside-out’ analytic strategy. Study sites included professional partnership, corporate and publicly owned and managed primary care providers, and different configurations of organisational integration or separation of community health services, mental health services, social services and acute inpatient care. Results Starting from data about patients’ experiences of the co-ordination or under-co-ordination of care, we identified five care co-ordination mechanisms present in both the integrated organisations and the care networks; four main obstacles to care co-ordination within the integrated organisations, of which two were also present in the care networks; seven main obstacles to care co-ordination that were specific to the care networks; and nine care co-ordination mechanisms present in the integrated organisations. Taking everything into consideration, integrated organisations appeared more favourable to producing continuities of care than did care networks. Network structures demonstrated more flexibility in adding services for small care groups temporarily, but the expansion of integrated organisations had advantages when adding new services on a longer term and a larger scale. Ownership differences affected the range of services to which patients had direct access; primary care doctors’ managerial responsibilities (relevant to care co-ordination because of their impact on general practitioner workload); and the scope for doctors to develop special interests. We found little difference between integrated organisations and care networks in terms of managerial discretion and performance. Conclusions On balance, an integrated organisation seems more likely to favour the development of care co-ordination and, therefore, continuities of care than a system of care networks. At least four different variants of ownership and management of organisationally integrated primary care providers are practicable in NHS-like settings. Future research is therefore required, above all to evaluate comparatively the different techniques for coordinating patient discharge across the triple interface between hospitals, general practices and community health services; and to discover what effects increasing the scale and scope of general practice activities will have on continuity of care

Domain modelling and the co-design of business rules in the telecommunication business area.

This paper discusses the development of an enterprise domain model in an environment where part of the domain knowledge is vague and not yet formalised in company-wide business rules. The domain model was developed for a young company starting in the telecommunications sector. The company relied on a number of stand-alone business support systems and sought for a manner to integrate them. There was opted for the development of an enterprise-wide domain model that had to serve as an integration layer to coordinate the stand-alone applications. A specific feature of the company was that it could build up its information infrastructure form scratch, so that many aspects of its business were still in the process of being defined. The paper will highlight parts of the Enterprise Model where there was a need for co-designing business rules together with the domain model. A result of this whole effort was that the company got more insight into important domain knowledge and developed a common understanding across functional areas of the way of doing business.domain modelling; business rules; object-oriented analysis; business process modelling;