976 resultados para Pickering, Timothy, 1745-1829.
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A statistical modeling method to accurately determine combustion chamber resonance is proposed and demonstrated. This method utilises Markov-chain Monte Carlo (MCMC) through the use of the Metropolis-Hastings (MH) algorithm to yield a probability density function for the combustion chamber frequency and find the best estimate of the resonant frequency, along with uncertainty. The accurate determination of combustion chamber resonance is then used to investigate various engine phenomena, with appropriate uncertainty, for a range of engine cycles. It is shown that, when operating on various ethanol/diesel fuel combinations, a 20% substitution yields the least amount of inter-cycle variability, in relation to combustion chamber resonance.
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This article reviews what international evidence exists on the impact of civil and criminal sanctions upon serious tax noncompliance by individuals. This construct lacks sharp definitional boundaries but includes large tax fraud and large-scale evasion that are not dealt with as fraud. Although substantial research and theory have been developed on general tax evasion and compliance, their conclusions might not apply to large-scale intentional fraudsters. No scientifically defensible studies directly compared civil and criminal sanctions for tax fraud, although one U.S. study reported that significantly enhanced criminal sanctions have more effects than enhanced audit levels. Prosecution is public, whereas administrative penalties are confidential, and this fact encourages those caught to pay heavy penalties to avoid publicity, a criminal record, and imprisonment.
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Purpose: To provide recommendations for construction clients who design and implement financial incentive mechanisms (FIMs) on projects. ---------- Methodology: Four large Australian building projects commissioned by government clients under managing contractor contracts and completed between 2001 and 2005 were examined to explore the ‘drivers’ that promoted motivation toward financial incentive goals. The results were triangulated across data sources, projects and stakeholder types. ---------- Findings: FIM design should incorporate: 1. flexibility to modify goals and measurement procedures over time, 2. multiple goals covering different project areas, 3. distribution of rewards across all the key organizations contributing to team performance (e.g. potentially not just the contractor, but the subcontractors and consultants) and a reward amount sufficient to be valued by potential recipients. FIM benefits are maximized through the following complementary procurement initiatives: 4. equitable contract risk allocation, 5. early contractor involvement in design, 6. value-driven tender selection, 7. relationship workshops, and 8. future work opportunities.---------- Research Limitations: This paper provides practical recommendations to industry and hence does not emphasize theoretical aspects.---------- Practical Implications: The uptake of these recommendations is likely to increase the impact of FIMs on motivation and improve project and industry outcomes. Although the study focuses on government clients of building projects, all the recommendations would seem to apply equally to private-sector clients and to non-building projects.---------- Originality: In order to improve motivation and reward high performance, clients are increasingly using FIM in their construction contracts. Despite the rising use of financial incentives, there is a lack of comprehensive construction-specific knowledge available to help clients maximize outcomes. The study addresses this gap in the literature.
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Construction industry observers tout the use of financial incentives as promoters of motivation and commitment on projects. Yet, little empirical evidence exists concerning their effectiveness. What are the drivers of motivation on construction projects? The reasons that construction project participants are motivated to pursue voluntary incentive goals are examined through four Australian case studies. The results demonstrate the critical role played by project relationships and equitable contract conditions in promoting the effectiveness of financial incentives. In the context of a construction project, this study finds financial incentives to be less important to motivation and performance than relationship enhancement initiatives. This finding is unexpected and has implications for the design of project procurement strategies. These results suggest if project clients ignore the importance of relationship quality between participants, the impact of any financial incentive will be compromised.
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The use of appropriate financial incentives within construction projects can contribute to strong alignment of project stakeholder motivation with project goals. However, effective incentive system design can be a challenging task and takes skillful planning by client managers in the early stages of a project. In response to a lack of information currently available to construction clients in this area, this paper explores the features of a successful incentive system and identifies key learnings for client managers to consider when designing incentives. Our findings, based on data from a large Australian case study, suggest that key stakeholders place greater emphasis on the project management processes that support incentives than on the incentive itself. Further, contractors need adequate time and information to accurately estimate construction costs prior to their tender price submission to ensure cost-focused incentive goals remain achievable. Thus, client managers should be designing incentives as part of a supportive procurement strategy to maximize project stakeholder motivation and prevent goal misalignment.
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Thomas Young (1773-1829) carried out major pioneering work in many different subjects. In 1800 he gave the Bakerian Lecture of the Royal Society on the topic of the “mechanism of the eye”: this was published in the following year (Young, 1801). Young used his own design of optometer to measure refraction and accommodation, and discovered his own astigmatism. He considered the different possible origins of accommodation and confirmed that it was due to change in shape of the lens rather than to change in shape of the cornea or an increase in axial length. However, the paper also dealt with many other aspects of visual and ophthalmic optics, such as biometric parameters, peripheral refraction, longitudinal chromatic aberration, depth-of-focus and instrument myopia. These aspects of the paper have previously received little attention. We now give detailed consideration to these and other less-familiar features of Young’s work and conclude that his studies remain relevant to many of the topics which currently engage visual scientists.
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Purpose: The goal of this conceptual paper is to provide tools to help maximise the value delivered by infrastructure projects, by developing methods to increase adoption of innovative products during construction. Methods: The role of knowledge flows in determining innovation adoption rates is conceptually examined. A promising new approach is developed. Open innovation system theory is extended, by reviewing the role of three frameworks: (1) knowledge intermediaries, (2) absorptive capacity and (3) governance arrangements. Originality: We develop a novel open innovation system model to guide further research in the area of adoption of innovation on infrastructure projects. The open innovation system model currently lacks definition of core concepts, especially with regard to the impact of different degrees and types of openness. The three frameworks address this issue and add substance to the open innovation system model, addressing widespread criticism that it is underdeveloped. The novelty of our model is in the combination of the three frameworks to explore the system. These frameworks promise new insights into system dynamics and facilitate the development of new methods to optimise the diffusion of innovation. Practical Implications: The framework will help to reveal gaps in knowledge flows that impede the uptake of innovations. In the past, identifying these gaps has been difficult given the lack of nuance in existing theory. The knowledge maps proposed will enable informed policy advice to effectively harness the power of knowledge networks, increase innovation diffusion and improve the performance of infrastructure projects. The models developed in this paper will be used in planned empirical research into innovation on large scale infrastructure projects in the Australian built environment.
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Polarising the issue of governance is the increasingly acknowledged role of airports in regional economic development, both as significant sources of direct employment and as attractants of commerce through enhanced mobility (Vickerman, Spiekermann & Wegener 1999; Hakfoort, Poot & Rietveld 2001). Most airports were once considered spatially removed from their cities, but as cities have expanded their airports no longer sit distinct of the urban environment. This newfound spatial proximity means that decisions for land use and development on either city or airport land are likely to have impacts that affect one another in either or both the short- or long-term (Stevens, Baker and Freestone 2007). These impacts increase the demand for decision making to find ways of integrating strategies for future development to ensure that airport developments do not impede the sustainable growth of its city, and likewise that city developments do not impede the sustainable growth of its airport (Gillen 2006). However questions of how, under what conditions, and to what extent decision making integration might be suitable for “airport regions” are yet to be explored let alone answered.
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The relationship between participation in civic and political activities and membership of voluntary associations is now well established. What is less clear is the relative impacts of how much time people spend on group activities (associational intensity), and the number and type of groups that individuals are involved with (associational scope). Does it matter in terms of civic engagement, for example, whether one is a member of a quilting-circle or trade union? Does it matter whether association ‘membership’ is simply an annual payment or a major commitment of time and energy? In this article, we use a large survey to explore these questions empirically by focusing on the membership patterns and civic engagement practices of 4,001 citizens drawn from eight suburbs across Greater Melbourne, Australia. Our findings indicate that, while associational intensity is positively related to civic engagement, associational scope (the number of group memberships per person), is a more influential determinant of the level of civic and political participation. The results also suggest that while all forms of associationalism are important in terms of fostering greater levels of civic activity, not all forms have the same impact.
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Training designed to support and strengthen higher-order mental abilities now often involves immersion in Virtual Reality where dangerous real world scenarios can be safely replicated. However despite the growing popularity of advanced training simulations, methods for evaluating their use rely heavily on subjective measures or analysis of final outcomes. Without dynamic, objective performance measures the outcome of training in terms of impact on cognitive skills and ability to transfer newly acquired skills to the real world is unknown. The relationship between affective intensity and cognitive learning provides a potential new approach to ensure the processing of cognitions which occur prior to final outcomes, such as problem-solving and decision-making, are adequately evaluated. This paper describes the technical aspects of pilot work recently undertaken to develop a new measurement tool designed to objectively track individual affect levels during simulation-based training.
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Aim and objective: The primary aim was to examine the prevalence of poststroke depression in Chinese stroke survivors six months after discharge from a rehabilitation hospital. A second aim was to determine whether six-month poststroke depression was associated with psychological, social and physical outcomes and demographic variables.---------- Background: There has been increasing recognition of the influence of depression on poststroke recovery. While some previous studies report associations between depression and social, psychological, physical and clinical outcomes, few studies had sufficient sample sizes for regression analysis thereby limiting the clinical applicability of their findings. ---------- Design: A cross-sectional design was used.---------- Method: Data were collected from 124 male and 86 female stroke survivors (mean age 71Æ7, SD 10Æ2 years). The Geriatric Depression Scale was used to measure depression, the State Self-esteem Scale to measure state self-esteem, the London Handicap Scale to measure participation restriction, the Social Support Questionnaire to measure satisfaction with social support and the Modified Barthel Index to measure functional ability. Results. Forty-two survivors (20Æ5%) reported mild and 33 (16Æ1%) reported severe depression. The presence of depression was associated with low levels of state self-esteem, social support satisfaction and functional ability. Logistic regression analysis revealed that these variables were statistically significant in predicting the probability of having depression (p < 0Æ05). ---------- Conclusions: Analyses in the present study revealed distinct patterns of correlates of depression, and the results were in agreement with prior studies that depression has a consistent positive ssociation with physical disability, living arrangements and social support and no significant association with the different types of brain lesion. Relevance to clinical practice. There is a need, routinely, to assess stroke survivors for depression and, where necessary, to intervene with the aim of enhancing psychological and social well-being.
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The main objective of this paper is to detail the development of a feasible hardware design based on Evolutionary Algorithms (EAs) to determine flight path planning for Unmanned Aerial Vehicles (UAVs) navigating terrain with obstacle boundaries. The design architecture includes the hardware implementation of Light Detection And Ranging (LiDAR) terrain and EA population memories within the hardware, as well as the EA search and evaluation algorithms used in the optimizing stage of path planning. A synthesisable Very-high-speed integrated circuit Hardware Description Language (VHDL) implementation of the design was developed, for realisation on a Field Programmable Gate Array (FPGA) platform. Simulation results show significant speedup compared with an equivalent software implementation written in C++, suggesting that the present approach is well suited for UAV real-time path planning applications.
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The INEX 2010 Focused Relevance Feedback track offered a refined approach to the evaluation of Focused Relevance Feedback algorithms through simulated exhaustive user feedback. As in traditional approaches we simulated a user-in-the loop by re-using the assessments of ad-hoc retrieval obtained from real users who assess focused ad-hoc retrieval submissions. The evaluation was extended in several ways: the use of exhaustive relevance feedback over entire runs; the evaluation of focused retrieval where both the retrieval results and the feedback are focused; the evaluation was performed over a closed set of documents and complete focused assessments; the evaluation was performed over executable implementations of relevance feedback algorithms; and �finally, the entire evaluation platform is reusable. We present the evaluation methodology, its implementation, and experimental results obtained for nine submissions from three participating organisations.
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Research methodology in the discipline of Art & Design has been a topic for much debate in the academic community. The result of such avid and ongoing discussion appears to be a disciplinary obsession with research methodologies and a culture of adopting and adapting existing methodologies from more established disciplines. This has eventuated as a means of coping with academic criticism and as an attempt to elevate Art & Design to a ‘real academic status’. Whilst this adoption has had some effect in tempering the opinion of Art & Design research from more ‘serious’ academics the practice may be concealing a deeper problem for this discipline. Namely, that knowledge transfer within creative practice, particularly in fashion textiles design practice, is largely tacit in nature and not best suited to dissemination through traditional means of academic writing and publication. ----- ----- There is an opportunity to shift the academic debate away from appropriate (or inappropriate) use of methodologies and theories to demonstrate the existence (or absence) of rigor in creative practice research. In particular, the changing paradigms for the definitions of research to support new models for research quality assessment (such as the RAE in the United Kingdom and ERA in Australia) require a re-examination of the traditions of academic writing and publication in relation to this form of research. It is now appropriate to test the limits of tacit knowledge. It has been almost half a century since Michael Polanyi wrote “we know more than we can tell” (Polanyi, 1967 p.4) at a time when the only means of ‘telling’ was through academic writing and publishing in hardcopy format. ----- ----- This paper examines the academic debate surrounding research methodologies for fashion textiles design through auto-ethnographic case study and object analysis. The author argues that, while this debate is interesting, the focus should be to ask: are there more effective ways for creative practitioner researchers to disseminate their research? The aim of this research is to examine the possibilities of developing different, more effective methods of ‘telling’ to support the transfer of tacit knowledge inherent in the discipline of Fashion Textiles Design.
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In this paper we present a real-time foreground–background segmentation algorithm that exploits the following observation (very often satisfied by a static camera positioned high in its environment). If a blob moves on a pixel p that had not changed its colour significantly for a few frames, then p was probably part of the background when its colour was static. With this information we are able to update differentially pixels believed to be background. This work is relevant to autonomous minirobots, as they often navigate in buildings where smart surveillance cameras could communicate wirelessly with them. A by-product of the proposed system is a mask of the image regions which are demonstrably background. Statistically significant tests show that the proposed method has a better precision and recall rates than the state of the art foreground/background segmentation algorithm of the OpenCV computer vision library.