A quality of service based framework for dynamic, dependable systems

There is currently much UK government and industry interest towards the integration of complex computer-based systems, including those in the military domain. These systems can include both mission critical and safety critical applications, and therefore require the dependable communication of data. Current modular military systems requiring such performance guarantees are mostly based on parameters and system states fixed during design time, thus allowing a predictable estimate of performance. These systems can exhibit a limited degree of reconfiguration, but this is typically within the constraints of a predefined set of configurations. The ability to reconfigure systems more dynamically, could lead to further increased flexibility and adaptability, resulting in the better use of existing assets. Current software architecture models that are capable of providing this flexibility, however, tend to lack support for dependable performance. This thesis explores the benefits for the dependability of future dynamic systems, built on a publish/subscribe model, from using Quality of Service (QoS) methods to map application level data communication requirements to available network resources. Through this, original contributions to knowledge are created, including; the proposal of a QoS framework that specifies a way of defining flexible levels of QoS characteristics and their use in the negotiation of network resources, a simulation based evaluation of the QoS framework and specifically the choice of negotiation algorithm used, and a test-bed based feasibility study. Simulation experimentation conducted comparing different methods of QoS negotiation gives a clear indication that the use of the proposed QoS framework and flexible negotiation algorithm can provide a benefit in terms of system utility, resource utilisation, and system stability. The choice of negotiation algorithm has a particularly strong impact on these system properties. The cost of these benefits comes in terms of the processing power and execution time required to reach a decision on the acceptance of a subscriber. It is suggested, given this cost, that when computational resources are limited, a simpler priority based negotiation algorithm should be used. Where system resources are more abundant, however, the flexible negotiation algorithm proposed within the QoS framework can offer further benefits. Through the implementation of the QoS framework within an existing military avionics software architecture based emulator on a test-bed, both the technical challenges that will need to be overcome and, more importantly, the potential viability for the inclusion of the QoS framework have been demonstrated

The usage of MIS applications to raise the efficiency and performance of the telecommunications services in the Kingdom of Saudi Arabia

PhD ThesisThere are different kinds of requirements on an information system. Of particular concern to this study are non-functional requirements (NFRs). These are aspects of a system. independent of any technical capabilities that it may have, which form a series of constraints on how a system will actually perform, and of which an organisation must take account in order to achieve success. This thesis studies non-functional requirements with particular reference to those that support an organisation in the process of structural change. Particular attention is paid to those non-functional requirements that will be constraints that hinder the performance and efficiency of any organisation if they are not fully understood and incorporated into the new information system. The way in which such non-functional requirements should be handled is illustrated by an extensive case study of the main provider of telecommunications services in Saudi Arabia. The researcher first took an interest in the Saudi telecommunications industry as a result of the recent moves to transform the country's telecommunications service from the traditional structure to a new system by the introduction of privatisation. The new modified system is called the Saudi Telecom Company (STC), though it is at present still under the effective control of the Saudi Ministry of Post, Telephone and Telegraph (MoPTT), the previous telecommunications service provider. The Saudi telecommunications service has been a monopoly managed through traditional public management systems, typically influenced by a dominant bureaucracy. The researcher's concern has been to study and describe the current management, structure, and operations (in particular the information systems) of the MoPTT in order to identifY key issues and potential areas for development which will help the MoPTT, as the STC, to offer a quality telecommunications service in the new competitive market. The researcher sets the telecommunications industry in Saudi Arabia in its national context by providing the political, cultural and economic background to the Kingdom of Saudi Arabia. This is of particular importance in view of the significance discovered by his study of non-technical environmental factors in the performance of the telecommunications service in the country. Using a combination of the qualitative and quantitative research approaches, the researcher examined the literature relevant to his topic and undertook a fieldtrip to Saudi Arabia, when he conferred extensively with MoPTI management and staff, observed MoPTI structures and operations, and consulted other experts in telecommunications. Reflection on the literature along with extensive fieldtrip consultation and observation reveal that a full account of the operations and potential of the Saudi telecommunications system cannot be provided by a consideration of its technical functions and processes alone. Due recognition must be given to the peculiarly Saudi setting of the service, and in particular attention must be paid to non-functional aspects, such requirements and constraints related to the environment in which the system has to operate. Culturally related non-functional requirements are of particular interest, and the case of Internet access in Saudi Arabia is examined, since it provides an especially good example of a non-functional requirement which is undergoing change, while still acting as a constraint on telecommunications usage. The case is related to a new conception of Saudisation, whereby Saudi personnel are no longer simply taking over and imitating western skills, but where they are providing Saudi solutions to Saudi questions. Using information gathered largely during his fieldtrip, the researcher provides a comprehensive description and discussion of the current MoPTT business areas, organisational structures, and information systems. Not only the commercial and technical features of these operations are examined, but also the extent to which they succeed in fulfilling or operating within the non-functional requirements and constraints, especially those of particularly Saudi origin, imposed upon them. Where appropriate, potential new approaches and directions for the MoPTI in relation to handling issues are indicated. Employing techniques developed by Dr. Michael Porter of Harvard University, an analysis has been provided of the of the MoPTI's enterprise strategy, since it is this which ultimately drives all the operations of the MoPTI, and upon which the MoPTI's telecommunications service will depend for commercial success in the new postprivatisation market. Based upon this analysis, the researcher has put forward explicit operational, managerial, and business proposals which should allow the MoPTT to seize the opportunities offered by privatisation, and to achieve success in both the domestic and the international telecommunications market. The researcher has felt able to identifY a number of specific factors within the MoPTr which might receive particular attention for revision and improvement, as they impact on all MoPTT operations and are of critical importance for its commercial success. These areas are strategic planning, marketing, training, customer relations, an integrated information system, and workforce management. As a result of his investigation into the operations of the MoPTT the researcher has been able to identify a new approach to the future of telecommunications in Saudi Arabia. He has designed an information architecture within which the MoPTT information systems might operate, and which takes full account of the role of non-functional aspects in the degree of success of such a complex operation. He offers a comprehensive description of the basis, operational details, and advantages of the implementation of this architecture for the MoPTT's information system operations. The particular benefits of Saudisation are stressed. It became clear during the research that the concept of Saudisation simply as the taking over and imitation of tasks previously carried out by non-Saudis (because they had the training and experience) was now inadequate. Saudisation has now to be understood as a cultural as well as a technical or business transformation, a dynamic concept relating both to enduring Saudi cultural values and to changing social attitudes and practices. Indeed this concept of Saudisation would repay further investigation as a suitable topic for future academic research, and the researcher makes this recommendation. He does so principally because the traditional understanding of the concept now seems inadequate and therefore a factor likely to inlnbit the truly indigenous development industry and services within Saudi ArabiaThe Government of Saudi Arabia: King AbdulAziz University

Effective contracting of uncertain performance outcomes : Allocating responsibility for performance outcomes to align goals across supply chain actors

This dissertation contributes to practice and literature by studying how organizations can effectively contract and sell uncertain performance outcomes. In Chapter 2, I study whether supplier shirking in response to outcome uncertainty can be mitigated by combining performance and behavior specification and evaluation. Based on the findings of this study, I advise purchasing managers to invest in the evaluation of perform

Quality assessment of service providers in a conformance-centric Service Oriented Architecture

In a Service Oriented Architecture (SOA), the goal of consumers is to discover and use services which lead to them experiencing the highest quality, such that their expectations and needs are satisfied. In supporting this discovery, quality assessment tools are required to establish the degree to which these expectations will be met by specific services. Traditional approaches to quality assessment in SOA assume that providers and consumers of services will adopt a performance-centric view of quality, which assumes that consumers will be most satisfied when they receive the highest absolute performance. However, adopting this approach does not consider the subjective nature of quality and will not necessarily lead to consumers receiving services that meet their individual needs. By using existing approaches to quality assessment that assume a consumer's primary goal as being optimisation of performance, consumers in SOA are currently unable to effectively identify and engage with providers who deliver services that will best meet their needs. Developing approaches to assessment that adopt a more conformance-centric view of quality (where it is assumed that consumers are most satisfied when a service meets, but not necessarily exceeds, their individual expectations) is a challenge that must be addressed if consumers are to effectively adopt SOA as a means of accessing services. In addressing the above challenge, this thesis develops a conformance-centric model of an SOA in which conformance is taken to be the primary goal of consumers. This model is holistic, in that it considers consumers, providers and assessment services and their relationship; and novel in that it proposes a set of rational provider behaviours that would be adopted in using a conformance-centric view of quality. Adopting such conformance-centric behaviour leads to observable and predictable patterns in the performance of the services offered by providers, due to the relationship that exists between the level of service delivered by the service and the expectation of the consumer. In order to support consumers in the discovery of high quality services, quality assessment tools must be able to effectively assess past performance information about services, and use this as a prediction of future performance. In supporting consumers within a conformance-centric SOA, this thesis proposes and evaluates a new set of approaches to quality assessment which make use of the patterns in provider behaviour described above. The approaches developed are non-trivial – using a selection of adapted pattern classification and other statistical techniques to infer the behaviour of individual services at run-time and calculating a numerical measure of confidence for each result that can be used by consumers to combine assessment information with other evidence. The quality assessment approaches are evaluated within a software implementation of a conformance-centric SOA, whereby they are shown to lead to consumers experiencing higher quality than with existing performance-centric approaches. By introducing conformance-centric principles into existing real-world SOA, consumers will be able to evaluate and engage with providers that offer services that have been differentiated based on consumer expectation. The benefits of such capability over the current state-of-the-art in SOA are twofold. Firstly, individual consumers will receive higher quality services, and therefore will increase the likelihood of their needs being effectively satisfied. Secondly, the availability of assessment tools which acknowledge the conformance-centric nature of consumers will encourage providers to offer a range of services for consumers with varying expectation, rather than simply offering a single service that aims to delivery maximum performance. This recognition will allow providers to use their resources more efficiently, leading to reduced costs and increased profitability. Such benefits can only be realised by adopting a conformance-centric view of quality across the SOA and by providing assessment services that operate effectively in such environments. This thesis proposes, develops and evaluates models and approaches that enable the achievement of this goal

INSTITUTIONAL INNOVATION AND ENVIRONMENTAL QUALITY

Second Annual Conference on Agricultural Policy and the Environment; Proceedings of a Conference Sponsored by University of Minnesota, Center for International Food and Agricultural Policy; Agricultural Development Regional Agency (ESAV); University of Padova; Lake Itasca, Minnesota, September 22-29, 1990, Volume III Contents: Institutional Arrangements for Managing Water Conflicts and the Role of Transaction Costs, by K. William Easter Incentives for Nonpoint Pollution Control: An Approach Based on a Principal-Agent Model, by Cesare Dosi and Michele Moretto Technical and Institutional Innovation in a Bureaucratic Setting: U.S. Land Conservation Policy and the Conservation Reserve, by C. Ford Runge and Vernon W. Ruttan Institutional Innovation in Local Public Agencies: A Case Study, by D. Agostini and C. ToffaninEnvironmental Economics and Policy, Institutional and Behavioral Economics,

A semantic framework for unified cloud service search, recommendation, retrieval and management

Cloud computing (CC) is a revolutionary paradigm of consuming Information and Communication Technology (ICT) services. However, while trying to find the optimal services, many users often feel confused due to the inadequacy of service information description. Although some efforts are made in the semantic modelling, retrieval and recommendation of cloud services, existing practices would only work effectively for certain restricted scenarios to deal for example with basic and non-interactive service specifications. In the meantime, various service management tasks are usually performed individually for diverse cloud resources for distinct service providers. This results into significant decreased effectiveness and efficiency for task implementation. Fundamentally, it is due to the lack of a generic service management interface which enables a unified service access and manipulation regardless of the providers or resource types.To address the above issues, the thesis proposes a semantic-driven framework, which integrates two main novel specification approaches, known as agility-oriented and fuzziness-embedded cloud service semantic specifications, and cloud service access and manipulation request operation specifications. These consequently enable comprehensive service specification by capturing the in-depth cloud concept details and their interactions, even across multiple service categories and abstraction levels. Utilising the specifications as CC knowledge foundation, a unified service recommendation and management platform is implemented. Based on considerable experiment data collected on real-world cloud services, the approaches demonstrate distinguished effectiveness in service search, retrieval and recommendation tasks whilst the platform shows outstanding performance for a wide range of service access, management and interaction tasks. Furthermore, the framework includes two sets of innovative specification processing algorithms specifically designed to serve advanced CC tasks: while the fuzzy rating and ontology evolution algorithms establish a manner of collaborative cloud service specification, the service orchestration reasoning algorithms reveal a promising means of dynamic service compositions