907 resultados para control over life


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A robot mounted camera is useful in many machine vision tasks as it allows control over view direction and position. In this paper we report a technique for calibrating both the robot and the camera using only a single corresponding point. All existing head-eye calibration systems we have encountered rely on using pre-calibrated robots, pre- calibrated cameras, special calibration objects or combinations of these. Our method avoids using large scale non-linear optimizations by recovering the parameters in small dependent groups. This is done by performing a series of planned, but initially uncalibrated robot movements. Many of the kinematic parameters are obtained using only camera views in which the calibration feature is at, or near the image center, thus avoiding errors which could be introduced by lens distortion. The calibration is shown to be both stable and accurate. The robotic system we use consists of camera with pan-tilt capability mounted on a Cartesian robot, providing a total of 5 degrees of freedom.

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Real estate development appraisal is a quantification of future expectations. The appraisal model relies upon the valuer/developer having an understanding of the future in terms of the future marketability of the completed development and the future cost of development. In some cases the developer has some degree of control over the possible variation in the variables, as with the cost of construction through the choice of specification. However, other variables, such as the sale price of the final product, are totally dependent upon the vagaries of the market at the completion date. To try to address the risk of a different outcome to the one expected (modelled) the developer will often carry out a sensitivity analysis on the development. However, traditional sensitivity analysis has generally only looked at the best and worst scenarios and has focused on the anticipated or expected outcomes. This does not take into account uncertainty and the range of outcomes that can happen. A fuller analysis should include examination of the uncertainties in each of the components of the appraisal and account for the appropriate distributions of the variables. Similarly, as many of the variables in the model are not independent, the variables need to be correlated. This requires a standardised approach and we suggest that the use of a generic forecasting software package, in this case Crystal Ball, allows the analyst to work with an existing development appraisal model set up in Excel (or other spreadsheet) and to work with a predetermined set of probability distributions. Without a full knowledge of risk, developers are unable to determine the anticipated level of return that should be sought to compensate for the risk. This model allows the user a better understanding of the possible outcomes for the development. Ultimately the final decision will be made relative to current expectations and current business constraints, but by assessing the upside and downside risks more appropriately, the decision maker should be better placed to make a more informed and “better”.

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This paper reviews the evidence relating to the question: does the risk of fungicide resistance increase or decrease with dose? The development of fungicide resistance progresses through three key phases. During the ‘emergence phase’ the resistant strain has to arise through mutation and invasion. During the subsequent ‘selection phase’, the resistant strain is present in the pathogen population and the fraction of the pathogen population carrying the resistance increases due to the selection pressure caused by the fungicide. During the final phase of ‘adjustment’, the dose or choice of fungicide may need to be changed to maintain effective control over a pathogen population where resistance has developed to intermediate levels. Emergence phase: no experimental publications and only one model study report on the emergence phase, and we conclude that work in this area is needed. Selection phase: all the published experimental work, and virtually all model studies, relate to the selection phase. Seven peer reviewed and four non-peer reviewed publications report experimental evidence. All show increased selection for fungicide resistance with increased fungicide dose, except for one peer reviewed publication that does not detect any selection irrespective of dose and one conference proceedings publication which claims evidence for increased selection at a lower dose. In the mathematical models published, no evidence has been found that a lower dose could lead to a higher risk of fungicide resistance selection. We discuss areas of the dose rate debate that need further study. These include further work on pathogen-fungicide combinations where the pathogen develops partial resistance to the fungicide and work on the emergence phase.

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Since the 1990s, international water sector reforms have centred heavily on economic and market approaches. In regard to water resources management, tradable water rights have been promoted, often supported by the neoliberal model adopted in Chile. Chile's 1981 Water Code was reformed to comprise a system of water rights that could be freely traded with few restrictions. International financial institutions have embraced the Chilean model, claiming that it results in more efficient water use, and potentially fosters social and environmental benefits. However, in Chile the Water Code is deeply contested. It has been criticised for being too permissive and has produced a number of problems in practice. Moreover, attempts to modify it have become the focus of a lengthy polemic debate. This paper employs a political ecology perspective to explore the socio-environmental outcomes of water management in Chile, drawing on a case study of agriculture in the semi-arid Norte Chico. The case illustrates how large-scale farmers exert greater control over water, while peasant farmers have increasingly less access. I argue that these outcomes are facilitated by the mode of water management implemented within the framework of the Water Code. Through this preliminary examination of social equity and the environmental aspects of water resources management in Chile, I suggest that the omission of these issues from the international debates on water rights markets is a cause for concern.

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Literacy as a social practice is integrally linked with social, economic and political institutions and processes. As such, it has a material base which is fundamentally constituted in power relations. Literacy is therefore interwoven with the text and context of everyday living in which multi-levelled meanings are organically produced at both individual and societal level. This paper argues that if language thus mediates social reality, then it follows that literacy defined as a social practice cannot really be addressed as a reified, neutral activity but that it should take account of the social, cultural and political processes in which literacy practices are embedded. Drawing on the work of key writers within the field, the paper foregrounds the primary role of the state in defining the forms and levels of literacy required and made available at particular moments within society. In a case-study of the social construction of literacy meanings in pre-revolutionary Iran, it explores the view that the discourse about societal literacy levels has historically constituted a key terrain in which the struggle for control over meaning has taken place. This struggle, it is argued, sets the interests of the state to maintain ideological and political control over the production of knowledge within the culture and society over and against the needs identified by the individual for personal development, empowerment and liberation. In an overall sense, the paper examines existing theoretical perspectives on societal literacy programmes in terms of the scope that they provide for analyses that encompass the multi-levelled power relations that shape and influence dominant discourses on the relative value of literacy for both the individual and society

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This paper presents a reflective narrative of the process of designing a PhD project. Using the analogy of the play 'One Man, Two Guvnors' , this paper discusses the tensions a beginning researcher faces in reconciling her own vision for a project with the academic demands of doctoral-level study. Focusing on an ethnographic study of a reading group for visually-impaired people, the paper explores how the researcher's developing understanding of the considerations necessary when working with disabled people impacted on the research design. In particular, it focuses on the conflict faced by doctoral students when working in a paradigm that requires actively involving research participants, thereby relinquishing some control over the project. The aim of the paper is to provide an honest narrative that will resonate with other beginning researchers.

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This paper summarizes and analyses available data on the surface energy balance of Arctic tundra and boreal forest. The complex interactions between ecosystems and their surface energy balance are also examined, including climatically induced shifts in ecosystem type that might amplify or reduce the effects of potential climatic change. High latitudes are characterized by large annual changes in solar input. Albedo decreases strongly from winter, when the surface is snow-covered, to summer, especially in nonforested regions such as Arctic tundra and boreal wetlands. Evapotranspiration (QE) of high-latitude ecosystems is less than from a freely evaporating surface and decreases late in the season, when soil moisture declines, indicating stomatal control over QE, particularly in evergreen forests. Evergreen conifer forests have a canopy conductance half that of deciduous forests and consequently lower QE and higher sensible heat flux (QH). There is a broad overlap in energy partitioning between Arctic and boreal ecosystems, although Arctic ecosystems and light taiga generally have higher ground heat flux because there is less leaf and stem area to shade the ground surface, and the thermal gradient from the surface to permafrost is steeper. Permafrost creates a strong heat sink in summer that reduces surface temperature and therefore heat flux to the atmosphere. Loss of permafrost would therefore amplify climatic warming. If warming caused an increase in productivity and leaf area, or fire caused a shift from evergreen to deciduous forest, this would increase QE and reduce QH. Potential future shifts in vegetation would have varying climate feedbacks, with largest effects caused by shifts from boreal conifer to shrubland or deciduous forest (or vice versa) and from Arctic coastal to wet tundra. An increase of logging activity in the boreal forests appears to reduce QE by roughly 50% with little change in QH, while the ground heat flux is strongly enhanced.

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In this article, we present FACSGen 2.0, new animation software for creating static and dynamic threedimensional facial expressions on the basis of the Facial Action Coding System (FACS). FACSGen permits total control over the action units (AUs), which can be animated at all levels of intensity and applied alone or in combination to an infinite number of faces. In two studies, we tested the validity of the software for the AU appearance defined in the FACS manual and the conveyed emotionality of FACSGen expressions. In Experiment 1, four FACS-certified coders evaluated the complete set of 35 single AUs and 54 AU combinations for AU presence or absence, appearance quality, intensity, and asymmetry. In Experiment 2, lay participants performed a recognition task on emotional expressions created with FACSGen software and rated the similarity of expressions displayed by human and FACSGen faces. Results showed good to excellent classification levels for all AUs by the four FACS coders, suggesting that the AUs are valid exemplars of FACS specifications. Lay participants’ recognition rates for nine emotions were high, and comparisons of human and FACSGen expressions were very similar. The findings demonstrate the effectiveness of the software in producing reliable and emotionally valid expressions, and suggest its application in numerous scientific areas, including perception, emotion, and clinical and euroscience research.

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It is generally accepted that the physical workplace environment affects employees’ satisfaction and, consequently, their perceived productivity and well-being. This study investigated whether employee “satisfaction” variables can predict perceived productivity, well-being and enjoyment at work, and if so, to what extent. The study also explored whether limiting employees’ control over their environment could save energy without compromising employees’ satisfaction and perceived productivity. Preoccupancy and post-occupancy evaluation studies were conducted, in terms of both energy consumption and employee perceptions, to make comparisons between a company’s old and current headquarters buildings, both located in the same area of London. The results showed that employees were more satisfied with their work environment at their new HQ, in general, than with that of their previous office. Also, employees’ self-reported productivity, well-being and enjoyment at work improved after the move. It was revealed that the combination of employees’ level of satisfaction with “interior use of space” and “physical conditions” was the best predictor of their perceived productivity, while satisfaction with “indoor facilities” was not a good predictor. In terms of energy performance, although the new HQ’s energy consumption per m2 was significantly less than that of the previous building, there was still a gap between the refurbishment design target and the actual performance of the building. The findings suggest that this gap could be due to a number of factors, including an ineffective use of interior space, and occupants’ behaviour.

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Auditing is often cited as playing an important role in managing agency-related costs and, accordingly, being integral to the sound functioning of capital markets. There may, however, be more to the attest function than a technical rational practice. By virtue of relying heavily on claims to technical expertise, professionalism, prudential judgement and public confidence, auditing is both a source of legitimacy for organisations and, paradoxically, dependent on claims to legitimacy for its continued existence. From this perspective, recent regulatory developments, purportedly enacted to increase arms-length control over the profession, may not only be about improving perceived audit quality and practice but also about ensuring continued faith in the well-established ‘rituals’ of the assurance function. A reporting duty imposed on South African external auditors, akin to whistle-blowing, is used as a case study to explore this perspective. In doing so, this paper contributes to the scant body of interpretive research on auditing, simultaneously offering one of the first insights into auditing regulation from an African perspective.

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The surface structure and morphology of the clean Re(11%21) surface has been investigated through combined low energy electron diffraction intensity analysis of data taken at multiple angles of incidence, scanning tunneling microscopy, and first-principles density functional calculations. The results show how this globally racemic surface terminates in two chirally distinct terraces, which show largescale out-of-plane atomic relaxations and in-plane lateral movement of the uppermost atoms. We further identify and discuss the initial stages of step bunching upon adsorption of oxygen that leads ultimately to the large-scale faceting of the surface. Finally, we present calculations of surface stress and the response to applied surface strain, which suggest routes to the exertion of control over the expression of chirality at the surface.

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Government initiatives in several developed and developing countries to roll-out smart meters call for research on the sustainability impacts of these devices. In principle smart meters bring about higher control over energy theft and lower consumption, but require a high level of engagement by end-users. An alternative consists of load controllers, which control the load according to pre-set parameters. To date, research has focused on the impacts of these two alternatives separately. This study compares the sustainability impacts of smart meters and load controllers in an occupied office building in Italy. The assessment is carried out on three different floors of the same building. Findings show that demand reductions associated with a smart meter device are 5.2% higher than demand reductions associated with the load controller.

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The sensitivity of sea breeze structure to sea surface temperature (SST) and coastal orography is investigated in convection-permitting Met Office Unified Model simulations of a case study along the south coast of England. Changes in SST of 1 K are shown to significantly modify the structure of the sea breeze immediately offshore. On the day of the case study, the sea breeze was partially blocked by coastal orography, particularly within Lyme Bay. The extent to which the flow is blocked depends strongly on the static stability of the marine boundary layer. In experiments with colder SST, the marine boundary layer is more stable, and the degree of blocking is more pronounced. Although a colder SST would also imply a larger land–sea temperature contrast and hence a stronger onshore wind – an effect which alone would discourage blocking – the increased static stability exerts a dominant control over whether blocking takes place. The implications of prescribing fixed SST from climatology in numerical weather prediction model forecasts of the sea breeze are discussed.

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The effects of auditory distraction in memory tasks have been examined to date with procedures that minimize participants’ control over their own memory processes. Surprisingly little attention has been paid to metacognitive control factors which might affect memory performance. In this study, we investigate the effects of auditory distraction on metacognitive control of memory, examining the effects of auditory distraction in recognition tasks utilizing the metacognitive framework of Koriat and Goldsmith (1996), to determine whether strategic regulation of memory accuracy is impacted by auditory distraction. Results replicated previous findings in showing that auditory distraction impairs memory performance in tasks minimizing participants’ metacognitive control (forced-report test). However, the results revealed also that when metacognitive control is allowed (free-report tests), auditory distraction impacts upon a range of metacognitive indices. In the present study, auditory distraction undermined accuracy of metacognitive monitoring (resolution), reduced confidence in responses provided and, correspondingly, increased participants’ propensity to withhold responses in free-report recognition. Crucially, changes in metacognitive processes were related to impairment in free-report recognition performance, as the use of the ‘don’t know’ option under distraction led to a reduction in the number of correct responses volunteered in free-report tests. Overall, the present results show how auditory distraction exerts its influence on memory performance via both memory and metamemory processes.

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Irrelevant sound accompanying the processes of encoding and retrieval of verbal events impairs memory performance. However, the degree of impairment is highly dependent on a range of factors. Some of them lie outside rememberers’ control, like the semantic content of distracting sound or the nature of a test used to assess memory. Others, like a strategy used to encode memoranda, rest under control of the rememberer. In this paper the factors that modulate memory impairment are outlined and discussed in terms of multiple mechanisms contributing to memory impairment under auditory distraction. The mechanisms of a capture of attention by distraction, interference of automatic seriation of distraction and voluntary seriation of memoranda, semantic inhibition of distraction, and blocking of memoranda by semantically related distracters are described. Results that demonstrate how these mechanisms determine memory impairment under auditory distraction are also discussed. Particular attention is devoted to the possibility of voluntary control over the workings of these mechanisms and the conditions under which the negative impact of auditory distraction upon memory performance could be minimised.