Showing papers by "University of Westminster published in 1995"

Structural transformations of the public sphere

Abstract: We are living in times in which spatial frameworks of communication are in a state of upheaval. The old hegemony of state‐structured and territorially‐bound public life mediated by radio, television, newspapers and books is being rapidly eroded. In its place are developing a multiplicity of networked spaces of communication which are not tied immediately to territory, and which irreversibly fragment anything resembling a single, spatially‐integrated public sphere within a nation‐state framewrok. The conventional ideal of a unified public sphere and its corresponding vision of a republic of citizens striving to live up to some “public good”; are obsolete. Public life is today subject to “medievalization”;, not as Habermas defined it in Strukturwandel der Offentlichkeit, but in the different sense of a developing and complex mosaic of differently sized, overlapping and interconnected public spheres. This restructuring of communicative space forces us to revise our understanding of public life and its “partn...

A Formal Framework for Agency and Autonomy

Abstract: With the recent rapid growth of interest in MultiAgent Systems, both in artificial intelligence and software engineering, has come an associated difficulty concerning basic terms and concepts. In particular, the terms agency and autonomy are used with increasing frequency to denote different notions with different connotations. In this paper we lay the foundations for a principled theory of agency and autonomy, and specify the relationship between them. Using the Z specification language, we describe a three-tiered hierarchy comprising objects, agents and autonomous agents where agents axe viewed as objects with goals, and autonomous agents are agents with motivations.

A review of Goal Programming and its applications

Abstract: This paper presents a review of the current literature on the branch of multi-criteria decision modelling known as Goal Programming (GP). The result of our indepth investigations of the two main GP methods, lexicographic and weighted GP together with their distinct application areas is reported. Some guidelines to the scope of GP as an application tool are given and methods of determining which problem areas are best suited to the different GP approaches are proposed. The correlation between the method of assigning weights and priorities and the standard of the results is also ascertained.

Public transport : its planning, management, and operation

Abstract: 1 Organisation and Control of Transport in the British Isles 2 The Role of Public Transport 3 Service Quality and Marketing 4 The Technology of Bus and Coach Systems 5 Urban Railways and Rapid Transit Systems 6 Network Planning 7 Costing and Cost Allocation Methods 8 Pricing Theory and Practice 9 Rural Public Transport 10 Intercity Public Transport 11 Some Current Policy Issues

Political economy and cultural studies: Reconciliation or divorce?

Abstract: The author considers that the profound antagonism between political economy and cultural studies can be overcome provided cultural studies stop accusing political economy of economism and reductionism. He nevertheless calls for researchers in cultural studies to better take into consideration economic determinations in their theorization of power in relation to culture, and not to be too quick to reject possibilities of false consciousness of individuals faced with the cultural and media productions on offer. In this text, still deeply steeped in the traditional Marxist model, the author finally considers the place granted to race and gender relations in structures of domination, by defending the primacy of social class.

Self-Employment Career Dynamics: The Case of `Unemployment Push' in UK Book Publishing:

Abstract: The recent revival of self-employment in the UK and other advanced industrialized economies has been viewed contrastingly as an indication of economic vitality and, alternatively, as a form of labo...

Estimating the time Varying Components of international stock markets' risk

Abstract: In this study an alternative approach for assessing securities' risk is applied. Various authors have argued that security returns are not homoskedastic but exhibit variation over time. They have observed that large changes tend be followed by more large changes in either direction, and so volatility must be predictably high after large changes. This phenomenon of securities' volatility, referred to as clustering, has important implications for security pricing and risk management. Among the most popular techniques currently used to capture the clustering effect and to forecast future volatilityare those belonging to the family of Autoregressive Conditional Heteroskedastic (ARCH) models. The main aim of this paper is to investigate whether such volatility modelling can be used to capture the time variation not only in the total risk of a security return but also its systematic and unsystematic components. Using weekly local stock market data, the time varying beta with the World Index has been estimated v...

Road Pricing: The Public Viewpoint

Abstract: While many academics and practitioners in the transport field now consider the case for introducing road user charging to be a very strong one, as a mechanism for making drivers pay the various externalities associated with their vehicle use, there are many cities around the world where schemes which sought to apply such principles to car traffic were not implemented due to adverse public reaction and political pressures — even though they had considerable technical merit. Instances include proposals for supplementary licensing in London and Kuala Lumpur, and for electronic road pricing in Hong Kong (Borins, 1988) and the Netherlands (Stoelhorst and Zandbergen, 1990), as well as the various attempts to increase petrol taxes in the United States.

Encouraging drinking at safe limits on single occasions: the potential contribution of protection motivation theory

Abstract: Protection Motivation Theory (PMT) is considered as a possible framework for understanding and moderating higher-risk drinking. To this end questionnaire data were collected from 196 participants about levels of their current drinking and, after they have been alerted to the dangers of excess drinking on single occasions, their cognitions relating to drinking and their intentions for future single occasion drinking. Comparisons of higher and lower risk drinkers among the sample provided support for the applicability of PMT, revealing differences in their cognitions and in their adaptive and maladaptive coping. A supplementary path analysis revealed that health beliefs and coping strategies associated with PMT, together with demographics, account for 42% of the vanance in behavioural intentions. These results suggest that PMT could prove a valuable tool for those working in alcohol research and education. Implications for the design of effective interventions are discussed.

For a Phenomenology of Radio and Television

Abstract: Cet article propose une premiere exploration des conditions d'intelligibilite de la production d'emissions de radio et de television. La question est posee du point de vue de la vie quotidienne. Le point de depart de cette reflexion est le fait evident que la radio et la television sont considerees par tous comme faisant naturellement partie du mobilier de la vie quotidienne. Dans ce contexte precis, il apparait donc que la television et la radio peuvent etre obtenues par tous sans probleme. Cet article tente d'expliciter cette derniere affirmation. Il fait appel a un certain nombre de disciplines proches ayant un interet commun dans l'intelligibilite des pratiques sociales de la vie quotidienne : la sociologie interactionniste, l'ethnomethodologie et l'analyse conversationnelle, ainsi que la pragmatique et la philosophie du langage ordinaire. L'influence de l'analyse ontologique d'Heidegger (1962) (Being and Time) de l'existence ordinaire en tant qu'« etre dans le monde » est largement mise en avant

An Evaluation of Image Quality Metrics

Abstract: Many metrics have been proposed, over a period of thirty years, which are able to predict image quality in the form of single numbers. These metrics reduce a number of physical measurements to single values for predictions of perceptions of the quality of many different types of images from statistical evaluations by panels of observers. One problem concerned with the determination of any metric is which eye modulation transfer function (contrast sensitivity function, CSF) to use. It is only since 1992 that a physical model for determining the CSF of the eye viewing conditions. This paper reviews image quality metrics for sharpness and noise both independently and in combination

Thalassiosira species (Bacillariophyceae) from a Scottish sea-loch

Abstract: During the spring diatom blooms of 1992 and 1993 in Loch Creran, Scotland, regular water column and sediment samples were collected, examined, and species composition of the phytoplankton determined. Thalassiosira species were found to be a major bloom constituent. Species were identified from specimens cultured from sediments and isolated from vertical net hauls, using light and scanning electron microscopy. Of the 17 species positively determined, only Thalassiosira angulata, T. anguste-lineata, T. eccentrica, T. gravida, T. minima, T. nordenskioeldii, T. rotula and T. tenera have been previously reported in Scottish waters. Other species, for example Thalassiosira pseudonana and T. punctigera, have been noted elsewhere in the British Isles but not along the Scottish west coast. Several species, namely Thalassiosira concaviuscula, T. constricta, T. delicatula, T. kuschirensis, T. oceanica, T. pacifica and T. tealata, are new records for the British Isles. One unidentified taxon is illustrated. Descriptions, illustrations and a key are provided for the 18 taxa.

Engagement and Cooperating in Motivated Agent Modelling

Abstract: The title of this paper suggests two distinct aspects of the models that we propose and consider. The first of these is the modelling of other agents by motivated agents. That is to say that the act of modelling is itself motivated and constrained by the agent doing that modelling. The second aspect is that all such models will also be of motivated agents. It is not sufficient merely to know what other agents are like, but also to know why they are like that. This why aspect is what provides the extra information that allows a greater understanding of the interactions between entities in the world, and consequently provides for more resilient agents capable of effectively dealing with new and unforeseen circumstances in an uncertain world. Previous work has described a formal framework for agency and autonomy in which agents are viewed as objects with goals, and autonomous agents are agents with motivations. This paper considers the nature of cooperation within that framework. We identify distinct kinds of interaction, depending on the nature of the entities involved. In particular, we describe and specify the differences that arise in these interactions which we characterise as engagements of non-autonomous agents, and cooperation between autonomous agents.

Thalassiosira species (Bacillariophyceae) from a Scottish sea-loch

Abstract: During the spring diatom blooms of 1992 and 1993 in Loch Creran, Scotland, regular water column and sediment samples were collected, examined, and species composition of the phytoplankton determined. Thalassiosira species were found to be a major bloom constituent. Species were identified from specimens cultured from sediments and isolated from vertical net hauls, using light and scanning electron microscopy. Of the 17 species positively determined, only Thalassiosira angulata, T. anguste-lineata, T. eccentrica, T. gravida, T. minima, T. nordenskioeldii, T. rotula and T. tenera have been previously reported in Scottish waters. Other species, for example Thalassiosira pseudonana and T. punctigera, have been noted elsewhere in the British Isles but not along the Scottish west coast. Several species, namely Thalassiosira concaviuscula, T. constricta, T. delicatula, T. kuschirensis, T. oceanica, T. pacifica and T. tealata, are new records for the British Isles. One unidentified taxon is illustrated. Descriptions, illustrations and a key are provided for the 18 taxa.

A Formal View of Social Dependence Networks

Abstract: In response to the problems that have arisen regarding the terminology and concepts of agent-oriented systems, previous work has described a formal framework for understanding agency and autonomy In particular, this work made the claim that the framework could serve as a vehicle for the precise presentation and evaluation of models and theories of multi-agent systems We support this claim by outlining the framework and refining it through adding further levels of detail to formalise the concepts of external descriptions and social dependence networks Social Dependence Networks are a valuable source of information about the relationships within a multi-agent world They allow agents to reason about the resources and capabilities of others in order that they may enter into a negotiation to persuade these others to assist them in completing their tasks By formalising social dependence networks within the framework we are able to identify deficiencies in the original characterisation of the networks and the external descriptions of agents within them We address these deficiencies, and offer a modified view which removes much of the ambiguity and presents a stronger and more consistent formal model In reformulating these networks in this way, we also present a case study which shows how the formal framework that has been previously developed can be applied to provide an environment in which we can describe and reason about theories and models of multi-agent systems

General algorithms for reduced-adder integer multiplier design

Abstract: The problem of reducing the number of adders required to perform shift-and-add multiplication is addressed for hardware and software applications. Algorithms invented for each of these applications are compared and found to have similar performances in general. Improved results are achieved by selecting the best design of the two.

Elimination of Transients in Time-Varying Allpass Fractional Delay Filteres with Applications to Digital Waveguide Modeling

Abstract: This paper considers discrete-time allpass filters that implement a time-varying fractional delay. These recursive filters are desirable from the point of view of implementational efficiency and flat magnitude response, but they are prone to transient effects when their parameters are changed. A state variable update approach to this problem is reviewed, the basic idea of which is to modify also the state of the filter when coefficients are changed so that the filter enters a new state smoothly without transient attacks. This method is adapted to give a new and simple practical method for eliminating the transients. The effectiveness of the new technique is verified by applying it to a digital waveguide model of a vibrating string.

Offset windowing for FIR fractional-sample delay

Abstract: Non-optimal FIR filters used for fractional-sample delay, despite their wideband nature, are shown to benefit significantly from application of windowing. Here simple raised-cosine windows prove to be very effective, particularly if they are cast as asymmetric modifications of their conventional forms. The offset von Hann window is surprisingly potent when the number of coefficients is large and window offset coincides with the fractional delay required of the overall filter.

Tracking and Recognition of Face Sequences

Abstract: In this work, we address the issue of encoding and recognition of face sequences that arise from continuous head movement. We detect and track a moving head before segmenting face images from on-line camera inputs. We measure temporal changes in the pattern vectors of eigenface projections of successive image frames of a face sequence and introduce the concept of “temporal signature” of a face class. We exploit two different supervised learning algorithms with feedforward and partially recurrent neural networks to learn possible temporal signatures. We discuss our experimental results and draw conclusions.

Structuring a Z Specification to Provide a Formal Framework for Autonomous Agent Systems

Abstract: This paper describes a project which is using Z in the field of artificial intelligence (AI) to provide a defining framework for agency and autonomy. Specifically, the use of Z has provided a means for escaping from the terminological chaos surrounding agency and autonomy that is prevalent not just in the AI community, but also in other areas of computer science. We outline how we have developed a Z specification which serves as a framework that satisfies three distinct requirements. First, a framework should be defining in the sense that it must precisely and unambiguously provide meanings for the common concepts and terms. Second, it should be designed in such a way as to enable alternative models of particular classes of system to be explicitly described, compared and evaluated. Third, the framework should be sufficiently well-structured to provide a foundation for subsequent development of increasingly more refined concepts. The state based specification language Z is accessible to researchers from a variety of different backgrounds and allows us to provide a consistent unified formal account of an abstract agent system.

Application of holonic methodologies to problem diagnosis in a steel rod mill

Abstract: Holonic architectures have been suggested as a possible building block for future manufacturing systems. The term holonic implies a unit in manufacturing that demonstrates the dual characteristics of autonomous behaviour (when required) and the ability to function cooperatively when the situation requires it. One of the key functions that is important to both of these properties is the need for the manufacturing unit to be able to (self) diagnose performance and functional failures in a systematic manner. This paper proposes a generic methodology for self-diagnosis within a holonic manufacturing system, in which faults and problems are analysed as a standard function of the system.

Euralille 'Boosterism' At the Centre of Europe

Abstract: This article is concerned with how far largely US- based literature about pro-growth politics can be applied in European circumstances. It does this by examining the political context for the devel...

Detection of a protein which binds specifically to the upstream region of the pcbAB gene in Penicillium chrysogenum

Abstract: The upstream region of the pcbAB gene from Penicillium chrysogenum was screened for protein-binding sites using an electromobility shift assay. A specific protein/DNA interaction was detected within a fragment covering the region-387 to-242 relative to the pcbAB translational start codon. The appearance of this protein and pcbAB mRNA in culture extracts occurred at the same time point in fermentations, suggesting that the protein might be a transcription activator. The putative upstream activating sequence was located more precisely using cross-competition assays. These indicated the involvement of the 7-bp motif TGCCAAG in the binding of the protein.

Importance of multi-dimensional conductive heat flows in and around buildings

Abstract: The modelling of certain structures in a manner consistent with current practice can lead to significant errors as a result of the non-treatment of multi-dimensional conductive heat flows. A series of multi-dimensional simulations using a modified whole building thermal simulation model have been performed in order to highlight this problem. As a result, it is suggested that all building thermal simulation models should offer a facility to model certain conductive heat flows in more than one dimension. In the case where a one-dimensional simulation is the only available option, sugggestions are offered on how to achieve improved simulations.