888 resultados para Full-Range Model


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Traditionally, geostatistical algorithms are contained within specialist GIS and spatial statistics software. Such packages are often expensive, with relatively complex user interfaces and steep learning curves, and cannot be easily integrated into more complex process chains. In contrast, Service Oriented Architectures (SOAs) promote interoperability and loose coupling within distributed systems, typically using XML (eXtensible Markup Language) and Web services. Web services provide a mechanism for a user to discover and consume a particular process, often as part of a larger process chain, with minimal knowledge of how it works. Wrapping current geostatistical algorithms with a Web service layer would thus increase their accessibility, but raises several complex issues. This paper discusses a solution to providing interoperable, automatic geostatistical processing through the use of Web services, developed in the INTAMAP project (INTeroperability and Automated MAPping). The project builds upon Open Geospatial Consortium standards for describing observations, typically used within sensor webs, and employs Geography Markup Language (GML) to describe the spatial aspect of the problem domain. Thus the interpolation service is extremely flexible, being able to support a range of observation types, and can cope with issues such as change of support and differing error characteristics of sensors (by utilising descriptions of the observation process provided by SensorML). XML is accepted as the de facto standard for describing Web services, due to its expressive capabilities which allow automatic discovery and consumption by ‘naive’ users. Any XML schema employed must therefore be capable of describing every aspect of a service and its processes. However, no schema currently exists that can define the complex uncertainties and modelling choices that are often present within geostatistical analysis. We show a solution to this problem, developing a family of XML schemata to enable the description of a full range of uncertainty types. These types will range from simple statistics, such as the kriging mean and variances, through to a range of probability distributions and non-parametric models, such as realisations from a conditional simulation. By employing these schemata within a Web Processing Service (WPS) we show a prototype moving towards a truly interoperable geostatistical software architecture.

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We describe a non-invasive phakometric method for determining corneal axis rotation relative to the visual axis (β) together with crystalline lens axis tilt (α) and decentration (d) relative to the corneal axis. This does not require corneal contact A-scan ultrasonography for the measurement of intraocular surface separations. Theoretical inherent errors of the method, evaluated by ray tracing through schematic eyes incorporating the full range of human ocular component variations, were found to be larger than the measurement errors (β < 0.67°, α < 0.72° and d < 0.08 mm) observed in nine human eyes with known ocular component dimensions. Intersubject variations (mean ± S.D.: β = 6.2 ± 3.4° temporal, α = 0.2 ± 1.8° temporal and d = 0.1 ± 0.1 mm temporal) and repeatability (1.96 × S.D. of difference between repeat readings: β ± 2.0°, α ± 1.8° and d ± 0.2 mm) were studied by measuring the left eyes of 45 subjects (aged 18-42 years, 29 females and 16 males, 15 Caucasians, 29 Indian Asians, one African, refractive error range -7.25 to +1.25 D mean spherical equivalent) on two occasions. © 2005 The College of Optometrists.

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This thesis examines the theoretical and empirical relationship between trade unions and productivity in the Korean auto and cement manufacturing industries, during the 1980s. It challenges the tenets of the existing debate by stressing the contingent nature of this relationship. In particular this thesis pinpoints inadequacies of econometric analysis as the only method of judging this association between union presence and productivity, because this ignores national and historical industrial relations contexts. Moreover, the polarity between positive and negative views of trade union influences on productivity is seen as needlessly limited, failing as it does to consider the full context of labour-management dynamics within the employment relationship. Empirically, this thesis focuses on the unionism and productivity during two contrasting political periods: the first a time of constraint on union action and the second a period of relative freedom. It examines these periods using a full range of quantitative and qualitative analysis. Of particular significant is the inclusion of attitude surveys of the relationship between the presence of unions and productivity conducted amongst workers, managers and trade union officials. The broad conclusion of the thesis is a rejection of the validity of continuing to examine the relationship between trade unions and productivity without locating this within national and historical industrial relations contexts.

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This research examines women GPs' careers, how they run their practices and how they reconcile professional and domestic lives. It looks at the particular experiences of women GPs who practise alone, and at the pressures in past practice experience which have led them to do so. It is argued that many of the problems of group practice which can be identified are attributable to gender. For example, one reason given for entering general practice is a desire to be able to provide the full range of medical care and not to specialise. Women GPs, however, may find themselves seeing more women patients for "women's problems" and children than they would freely choose. Women have not entered general practice in order to specialise in these areas of medicine. Indeed, if they had wanted to specialise in obstetrics, gynaecology or paediatrics they would have had difficulty advancing very far in these male-dominated areas of hospital hierarchy. Other gender related problems exist for women in general practice and practising single-handedly is one strategy that women GPs have used to counter the problems of working in male-dominated practices and partnerships. However, the twenty-four hour commitment of single-handed practice may bring further pressures in reconciling this with responsibility for home life. Out-of-hours cover, which can be viewed as the link between professional and domestic life, where the one intrudes into the other, is also examined in terms of the gender issues it raises. The interaction of gender and ethnicity is also considered for the 11 Asian women GPs in the study. Interviews were conducted with 29 single-handed women GPs in the Midlands. In addition, some cases were studied in greater depth by being observed in their surgeries and on home visits for a day each. A qualitative/feminist approach to analysis has been employed.

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Purpose – The purpose of this paper is to present the concept of global “strategic sustainability”, represented by a conceptual framework, the “spheres of strategic sustainability”. The paper examines routes, solutions and a vision for corporate strategic sustainability in the macro context of the global physical environment and the planet. This builds on previous research identifying key drivers and strategies for corporate sustainability. Design/methodology/approach – The paper is conceptual in nature and underpinned by Gaia theory, ecosystems theory and the laws of thermodynamics. These three offer specific foci for sustainability research including holism, integration and synthesis: without which, sustainability research would be difficult to achieve. Findings – The paper identifies two major domains – “corporate” and “consumer” strategic sustainability. It examines the corporate domain in which routes are identified through responses to existing globalisation, corporate strategy and corporate culture. Research limitations/implications – The paper provides insight and preliminary conceptual development towards a full theoretical model of corporate and consumer strategic sustainability. The framework will guide future conceptual and empirical investigations and broaden and deepen our understanding of how firm's can construct strategic business models that incorporate sustainability. Originality/value – The paper offers a conceptual framework that develops the concept of “corporate strategic sustainability” and provides positive, practical solutions to incorporating sustainability into business models. It also challenges the current dominant socio-economic paradigm and sets the scene for a more positive eco-paradigm that serves the present and future needs of the planet, environment, businesses and human society.

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This article contributes to contemporary debates concerning the impact of regulation on small business performance. Reassessing previous studies, we build our insights on their useful, but partial, approaches. Prior studies treat regulation principally as a static and negative influence, thereby neglecting the full range of regulatory effects on business performance. This study adopts a more nuanced approach, one informed by critical realism, that conceptualises social reality as stratified, and social causality in terms of the actions of human agents situated within particular social-structural contexts. We theorise regulation as a dynamic force, enabling as well as constraining performance, generating contradictory performance effects. Such regulatory effects flow directly from adaptations to regulation, and indirectly via relationships with the wide range of close and distant stakeholders with whom small businesses interact. Future research should examine these contradictory regulatory influences on small business performance.

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Differential clinical diagnosis of the parkinsonian syndromes, viz., Parkinson’s disease (PD), progressive supranuclear palsy (PSP), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA) can be difficult. Eye movement problems, however, are a chronic complication of many of these disorders and may be a useful aid to diagnosis. Hence, the presence in PSP of vertical supranuclear gaze palsy, fixation instability, lid retraction, blepharospasm, and apraxia of eyelid opening and closing is useful in separating PD from PSP. Moreover, atypical features of PSP include slowing of upward saccades, moderate slowing of downward saccades, the presence of a full range of voluntary vertical eye movements, a curved trajectory of oblique saccades, and absence of square-wave jerks. Downgaze palsy is probably the most useful diagnostic clinical symptom of PSP. By contrast, DLB patients are specifically impaired in both reflexive and saccadic execution and in the performance of more complex saccadic eye movement tasks. Problems in convergence in DLB are also followed by akinesia and rigidity. Abnormal ocular fixation may occur in a significant proportion of MSA patients along with excessive square-wave jerks, a mild supranuclear gaze palsy, a gaze-evoked nystagmus, a positioning down-beat nystagmus, mild-moderate saccadic hypometria, impaired smooth pursuit movements, and reduced vestibulo-ocular reflex (VOR) suppression. There may be considerable overlap between the eye movement problems characteristic of the various parkinsonian disorders, but taken together with other signs and symptoms, can be a useful aid in differential diagnosis, especially in the separation of PD and PSP.

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This paper considers the position of a large full-range business school and ways in which it can improve its efficiency and effectiveness, and enhance students' learning environment by the strategic use of academic-related staff within key roles in the School. Some of these roles have traditionally been undertaken by academic staff, but the increased complexity of the Business School environment makes it impossible for academic staff to undertake all roles if the School wants to be innovative and successful in a highly changing external environment. The investigation is carried out via a series of semi-structure interviews, conducted with academic and academic related staff across the School. This is compared with a review of recent literature in the subject. The paper concludes that both the efficient running of the School and the learning environment of students are improved via the partnership of academics and support staff. The findings reveal, however, that the use of academic-related staff must be done sensitively, to ensure that institutions do not become over bureaucratic or academics alienated in the drive to focus on the student experience.

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Flooding can have a devastating impact on businesses, especially on small- and medium-sized enterprises (SMEs) who may be unprepared and vulnerable to the range of both direct and indirect impacts. SMEs may tend to focus on the direct tangible impacts of flooding, limiting their ability to realise the true costs of flooding. Greater understanding of the impacts of flooding is likely to contribute towards increased uptake of flood protection measures by SMEs, particularly during post-flood property reinstatement. This study sought to investigate the full range of impacts experienced by SMEs located in Cockermouth following the floods of 2009. The findings of a questionnaire survey of SMEs revealed that businesses not directly affected by the flooding experienced a range of impacts and that short-term impacts were given a higher significance. A strong correlation was observed between direct, physical flood impacts and post-flood costs of insurance. Significant increases in the costs of property insurance and excesses were noted, meaning that SMEs will be exposed to increased losses in the event of a future flood event. The findings from the research will enable policy makers and professional bodies to make informed decisions to improve the status of advice given to SMEs. The study also adds weight to the case for SMEs to consider investing in property-level flood risk adaptation measures, especially during the post flood reinstatement process. © 2012 Blackwell Publishing Ltd and The Chartered Institution of Water and Environmental Management (CIWEM).

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This paper proposes a methodological scheme for the photovoltaic (PV) simulator design. With the advantages of a digital controller system, linear interpolation is proposed for precise fitting with higher computational efficiency. A novel control strategy that directly tackles two different duty cycles is proposed and implemented to achieve a full-range operation including short circuit (SC) and open circuit (OC) conditions. Systematic design procedures for both hardware and algorithm are explained, and a prototype is built. Experimental results confirm an accurate steady state performance under different load conditions, including SC and OC. This low power apparatus can be adopted for PV education and research with a limited budget.

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We propose a robust adaptive time synchronization and frequency offset estimation method for coherent optical orthogonal frequency division multiplexing (CO-OFDM) systems by applying electrical dispersion pre-compensation (pre-EDC) to the pilot symbol. This technique effectively eliminates the timing error due to the fiber chromatic dispersion, thus increasing significantly the accuracy of the frequency offset estimation process and improving the overall system performance. In addition, a simple design of the pilot symbol is proposed for full-range frequency offset estimation. This pilot symbol can also be used to carry useful data to effectively reduce the overhead due to time synchronization by a factor of 2.

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Станимир Д. Илиев, Нина Хр. Пешева - Представен е хибриден експериментално-числен метод, работещ в реално време, за определяне на макроскопичния динамичен контактен ъгъл, който менискусът на течност в съд формира с вертикална пластина, която се потапя или издърпва с постоянна скорост от съда с течността. Този метод е приложим, когато системата е в стационарно състояние. Методът се базира на пълния хидродинамичен модел на Войнов. Той позволява да се получи числено с висока точност стационарната форма на профила на динамичния менискус (и от там ъгълът на наклон на менискуса) като се използва като гранично условие експериментално определената височина на менискуса на пластината.

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Background - Aquaporin (AQP) water channels are best known as passive transporters of water that are vital for water homeostasis. Scope of review - AQP knockout studies in whole animals and cultured cells, along with naturally occurring human mutations suggest that the transport of neutral solutes through AQPs has important physiological roles. Emerging biophysical evidence suggests that AQPs may also facilitate gas (CO2) and cation transport. AQPs may be involved in cell signalling for volume regulation and controlling the subcellular localization of other proteins by forming macromolecular complexes. This review examines the evidence for these diverse functions of AQPs as well their physiological relevance. Major conclusions - As well as being crucial for water homeostasis, AQPs are involved in physiologically important transport of molecules other than water, regulation of surface expression of other membrane proteins, cell adhesion, and signalling in cell volume regulation. General significance - Elucidating the full range of functional roles of AQPs beyond the passive conduction of water will improve our understanding of mammalian physiology in health and disease. The functional variety of AQPs makes them an exciting drug target and could provide routes to a range of novel therapies.

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Low and high water periods create contrasting challenges for trees inhabiting periodically flooded wetlands. Low to moderate flood durations and frequencies may bring nutrient subsidies, while greater hydroperiods can be energetically stressful because of oxygen deficiency. We tested the hypothesis that hydroperiod affects the growth of mangrove seedlings and saplings in a greenhouse experiment by varying flood duration while keeping salinity and soil fertility constant. We measured the growth of mangrove trees along a hydroperiod gradient over a two-year period by tracking fine-scale diameter increment. Greenhouse growth studies indicated that under a full range of annual flood durations (0–8760 h/year), hydroperiod alone exerted a significant influence on growth for one species, Laguncularia racemosa, when flooding was imposed for two growing seasons. Field evaluations, on the other hand, indicated that increased flood duration may provide nutrient subsidies for tree growth. Diameter growth was related curvilinearly to site hydroperiod, including flood duration and frequency, as well as to salinity and soil fertility. An analysis of soil physico-chemical parameters suggests that phosphorus fertility, which was also linked directly to hydroperiod, is likely to influence growth on south Florida mangrove sites. The physical removal of phosphorus by greater flood frequencies from upland sources and/or addition of phosphorus from tidal flooding balanced against increased soil aeration and reduced water deficits may be an extremely important growth determinant for south Florida mangroves.

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This dissertation examines Mexico City’s material politics of print—the central actors engaged in making print, their activities and relationships, and the legal, business, and social dimensions of production—across the nineteenth century. Inside urban printshops, a socially diverse group of men ranging from manual laborers to educated editors collaborated to make the printed items that fueled political debates and partisan struggles in the new republic. By investigating how print was produced, regulated, and consumed, this dissertation argues that printers shaped some of the most pressing conflicts that marked Mexico’s first formative century: over freedom of expression, the role of religion in government, and the emergence of liberalism. Printers shaped debates not only because they issued texts that fueled elite politics but precisely because they operated at the nexus where new liberal guarantees like freedom of the press and intellectual property intersected with politics and patronage, the regulatory efforts of the emerging state, and the harsh realities of a post-colonial economy.

Historians of Mexico have typically approached print as a vehicle for texts written by elites, which they argue contributed to the development of a national public sphere or print culture in spite of low literacy levels. By shifting the focus to print’s production, my work instead reveals that a range of urban residents—from prominent printshop owners to government ministers to street vendors—produced, engaged, and deployed printed items in contests unfolding in the urban environment. As print increasingly functioned as a political weapon in the decades after independence, print production itself became an arena in struggles over the emerging contours of politics and state formation, even as printing technologies remained relatively unchanged over time.

This work examines previously unexplored archival documents, including official correspondence, legal cases, business transactions, and printshop labor records, to shed new light on Mexico City printers’ interactions with the emerging national government, and reveal the degree to which heated ideological debates emerged intertwined with the most basic concerns over the tangible practices of print. By delving into the rich social and cultural world of printing—described by intellectuals and workers alike in memoirs, fiction, caricatures and periodicals— it also considers how printers’ particular status straddling elite and working worlds led them to challenge boundaries drawn by elites that separated manual and intellectual labors. Finally, this study engages the full range of printed documents made in Mexico City printshops not just as texts but also as objects with particular visual and material qualities whose uses and meanings were shaped not only by emergent republicanism but also by powerful colonial legacies that generated ambivalent attitudes towards print’s transformative power.