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Search Results: 1 - 10 of 5418 matches for " Stuart Walker "
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Temporal Objects—Design, Change and Sustainability
Stuart Walker
Sustainability , 2010, DOI: 10.3390/su2030812
Abstract: In this paper, design for change is explored as a means of contributing to socio-economic equity while minimising environmental damage. To create a material culture capable of accommodating technological progress and aesthetic development while also adhering to the principles of sustainability, it becomes important to recognise the potential role of design for change. This theme is explored here by considering design within an integrated strategy that includes mass- and local-scale manufacturing, service provision and re-manufacture. General design objectives are developed that provide a basis for generating ‘critical design’ concepts. Engagement in the process of designing requires a transmutation from generalisations to specific design decisions. This process enriches our understandings of design for change and the concepts presented here articulate the ideas via form, function, materials and aesthetics. In doing so, they provide tangible expressions of the strategic implications. These ‘temporal objects’, which in this case rely on a relatively stable technology, highlight the importance of localisation and more distributed forms of innovation. In addition, they clarify the designer’s role in developing useful things that are capable of being continually transformed through time, with continuous use of technological components and changing aesthetic components that, through creative employment of materials, have virtually no detrimental environmental impacts.
Sermons In Stones. Argument And Artefact For Sustainability
Stuart Walker
Les Ateliers de l’éthique , 2010,
Abstract: The focus of the study is on the values, priorities and arguments needed to advance ‘design for sustainability’. The discussion critiques conventions related to innovation and technology and offers a product design approach that emphasises minimal intervention, integrated thinking-and-doing, reinstating the familiar, localization and the particularities of place. These interdependent themes are discussed in terms of their relationship to design for sustainability and are clarified through the conceptualization, design, production and use of a simple functional object that is, essentially, a ‘sym- bolic sustainable artefact’. Although it is fully functional, its practical usefulness in contemporary society would probably be seen as marginal. Its potential contribution is as a symbol of an alternative direction. It asks us to consider aspects of our humanity that are beyond instrumental approaches. It challenges sustainable initiatives that become so caught up in practical and environmental concerns that they fail to question the underlying values, priorities and social drivers which affect how we act in the world; those behaviours and norms that have created the very problems we are so urgently trying to tackle. The discussion is accompanied by a parallel series of photographs that document the relationship between argument, locale and the creation of the conceptual artefact. These photographs convey some of the qualitative differences between the place of much contemporary artefact acquisition, i.e. the shopping mall, and the particular locale that yielded the artefact created during this study; they are also useful in conveying the potential relationship that exist between place and the aesthetics of functional objects.
Empirical Performance Evaluation of Enhanced Throughput Schemes of IEEE802.11 Technology in Wireless Area Networks
Oladunni Femijemilohun,Stuart Walker
Computer Science , 2013,
Abstract: The success in the growing wireless standards can be measured by the achievement of quality of service (QoS) specifications by the designers. The IEEE802.11 wireless standards are widely accepted as wireless technology for wireless LAN. Efforts have been made over the years by the task group to provide adequate number of QoS enhancement schemes for the increasing numbers of multimedia applications. This paper examines the empirical performances of ad hoc wireless networks deployed on IEEE802.11 standard variants. A survey to some of the QoS schemes incorporated in IEEE802.11 wireless PHY layers were carried out. Then the effects of this enhancement schemes in relation to data throughput and system capacity and reliability in the newest technology deployed on IEEE802.11ac standards was investigated using real time applications and simulation based approaches.
Hybrid Optical and Electrical Network Flows Scheduling in Cloud Data Centres
Ibrahim Kabiru Musa,Stuart Walker
Computer Science , 2013, DOI: 10.5121/ijcsit.2013.5201
Abstract: Hybrid intra-data centre networks, with optical and electrical capabilities, are attracting research interest in recent years. This is attributed to the emergence of new bandwidth greedy applications and novel computing paradigms. A key decision to make in networks of this type is the selection and placement of suitable flows for switching in circuit network. Here, we propose an efficient strategy for flow selection and placement suitable for hybrid Intra-cloud data centre networks. We further present techniques for investigating bottlenecks in a packet networks and for the selection of flows to switch in circuit network. The bottleneck technique is verified on a Software Defined Network (SDN) testbed. We also implemented the techniques presented here in a scalable simulation experiment to investigate the impact of flow selection on network performance. Results obtained from scalable simulation experiment indicate a considerable improvement on average throughput, lower configuration delay, and stability of offloaded flows
A Dynamic Model of Information and Entropy
Michael C. Parker,Stuart D. Walker
Entropy , 2010, DOI: 10.3390/e12010080
Abstract: We discuss the possibility of a relativistic relationship between information and entropy, closely analogous to the classical Maxwell electro-magnetic wave equations. Inherent to the analysis is the description of information as residing in points of non-analyticity; yet ultimately also exhibiting a distributed characteristic: additionally analogous, therefore, to the wave-particle duality of light. At cosmological scales our vector differential equations predict conservation of information in black holes, whereas regular- and Z-DNA molecules correspond to helical solutions at microscopic levels. We further propose that regular- and Z-DNA are equivalent to the alternative words chosen from an alphabet to maintain the equilibrium of an information transmission system.
Beyond Abundance: Self-Interest Motives for Sustainable Consumption in Relation to Product Perception and Preferences
Anne Marchand,Stuart Walker,Tim Cooper
Sustainability , 2010, DOI: 10.3390/su2051431
Abstract: This paper presents results of a study that examined the perceptions and preferences of identified “responsible, sustainable consumers” with respect to functional products. The study is part of a larger research program that looks at material cultures and product design in relation to sustainable production and consumption. Based on empirical data gathered from among citizens attempting to follow sustainable lifestyles, the authors reflect on how the adoption of sustainable consumption patterns can not only be motivated by altruistic and environmental considerations, but also, significantly, by perceived personal benefits, including an expected increase in personal well-being. These motivations, together with how they unfold into preferences for particular product characteristics, are discussed. The paper concludes that the understanding of such motives, along with their implications for the ways in which products and services are conceived and positioned, may warrant further research as it can represent a key incentive for change towards a more sustainable future.
A Dynamic Theory of Information and Entropy
Michael C. Parker,Stuart D. Walker
Physics , 2004,
Abstract: We propose a new thermodynamic, relativistic relationship between information and entropy, which is closely analogous to the classic Maxwell electro-magnetic equations. Determination of whether information resides in points of non-analyticity or is more distributed in nature therefore relates directly to the well-known wave-particle duality of light. At cosmological scales our vector differential equations predict conservation of information in black holes, whereas regular and Z-DNA correspond to helical solutions at microscopic levels. We further propose that regular and Z-DNA are equivalent to the alternative words chosen from an alphabet to maintain the equilibrium of an information transmission system.
Information Transfer and Landauer's Principle
Michael C. Parker,Stuart D. Walker
Physics , 2003, DOI: 10.1016/j.optcom.2003.10.019
Abstract: In this paper we present an analysis of information transfer based on Landauer's principle (i.e. erasure of information is associated with an increase in entropy), as well as considerations of analyticity and causality. We demonstrate that holomorphic functions allowing complete analytic continuation cannot propagate any information, such that information transfer only occurs with analytic functions having points of non-analyticity (i.e. meromorphic functions). Such points of non-analyticity (or discontinuities) are incompatible with adiabaticity, so that information transfer must always be accompanied by a change in entropy: a dynamic reformulation of Landauer's Principle. In addition, since Brillouin proved that discontinuities cannot travel faster than the speed of light c, this also implies that information cannot be transferred at superluminal speeds.
Is Computation Reversible?
Michael C. Parker,Stuart D. Walker
Physics , 2004,
Abstract: Recent investigations into the physical nature of information and fundamental limits to information transmission have revealed questions such as the possibility of superluminal data transfer or not; and whether reversible computation (information processing) is feasible. In some respects these uncertainties stem from the determination of whether information is inherent in points of non-analyticity (discontinuities) or smoother functions. The close relationship between information and entropy is also well known, e.g. Brillouin's concept of negentropy (negative entropy) as a measure for information. Since the leading edge of a step-discontinuity propagates in any dispersive medium at the speed of light in vacuum as a precursor to the main body of the dispersed pulse, we propose in this paper to treat information as being intrinsic to points of non-analyticity (discontinuities). This allows us to construct a theory addressing these dilemmas in a fashion consistent with causality, and the fundamental laws of thermodynamics. A consequence of our proposition is that the movement of information is always associated with the dissipation of heat, and therefore that the concept of reversible classical computation is not tenable.
Information Transfer Time: The Role of Holomorphism, Stationary Phase, and Noise
Michael C. Parker,Stuart D. Walker
Physics , 2002,
Abstract: In this paper we present an analysis of information transfer time based on holomorphism, causality and the classical principle of stationary phase. We also make a preliminary study of the effect of noise on information transfer time, and find that noise tends to increase transfer times. Noise and information signals are both essentially acausal, such that analytic continuation (i.e. prediction) is impossible, which also implies that their frequency spectra cannot be holomorphic. This leads to the paradox of a non-holomorphic information-bearing light signal, yet whose underlying Maxwell equations governing the propagation of the EM wave describe a holomorphic function in spacetime. We find that application of stationary phase and entropy arguments circumvents this difficulty, with stationary phase only suggesting the most likely transfer times of an information signal in the presence of noise. Faster transit times are not excluded, but are highly improbable. Stationary phase solutions, by definition, do not include signal forerunners, whose detection in the presence of noise is also unreliable. Hence a finite information capacity ensues, as expected from Shannon's law, and information cannot be transferred faster than c. We also find that the method of stationary phase implies complex transfer times. However, by considering spacetime to be isomorphic with the complex temporal plane, we find that an imaginary time is equivalent to a real distance, and can be interpreted as the uncertainty in the spatial position of the information pulse. Finally, we apply our theory to a photonic band gap crystal, and find that information transfer speed and tunneling is always subluminal.
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