883 resultados para empirical data


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Despite the wealth of valuable information that has been generated by motivation studies to date, there are certain limitations in the common approaches. Quantitative and psychometric approaches to motivation research that have dominated in recent decades provided epiphenomenal descriptions of learner motivation within different contexts. However, these approaches assume homogeneity within a given group and often mask the variation between learners within the same, and different, contexts. Although these studies have provided empirical data to form and validate theoretical constructs, they have failed to recognise learners as individual ‘people’ that interact with their context. Learning context has become increasingly explicit in motivation studies, (see Coleman et al. 2007 and Housen et al. 2011), however it is generally considered as a background variable which is pre-existing and external to the individual. Stemming from the recent ‘social turn’ (Block 2003) in SLA research from a more cognitive-linguistic perspective to a more context-specific view of language learning, there has been an upsurge in demand for a greater focus on the ‘person in context’ in motivation research (Ushioda 2011). This paper reports on the findings of a longitudinal study of young English learners of French as they transition from primary to secondary school. Over 12 months, the study employed a mixed-method approach in order to gain an in-depth understanding of how the learners’ context influenced attitudes to language learning. The questionnaire results show that whilst the learners displayed some consistent and stable motivational traits over the 12 months, there were significant differences for learners within different contexts in terms of their attitudes to the language classroom and their levels of self-confidence. A subsequent examination of the qualitative focus group data provided an insight into how and why these attitudes were formed and emphasised the dynamic and complex interplay between learners and their context.

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The mixing of floes of different thickness caused by repeated deformation of the ice cover is modeled as diffusion, and the mass balance equation for sea ice accounting for mass diffusion is developed. The effect of deformational diffusion on the ice thickness balance is shown to reach 1% of the divergence effect, which describes ridging and lead formation. This means that with the same accuracy the mass balance equation can be written in terms of mean velocity rather than mean mass-weighted velocity, which one should correctly use for a multicomponent fluid such as sea ice with components identified by floe thickness. Mixing (diffusion) of sea ice also occurs because of turbulent variations in wind and ocean drags that are unresolved in models. Estimates of the importance of turbulent mass diffusion on the dynamic redistribution of ice thickness are determined using empirical data for the turbulent diffusivity. For long-time-scale prediction (≫5 days), where unresolved atmospheric motion may have a length scale on the order of the Arctic basin and the time scale is larger than the synoptic time scale of atmospheric events, turbulent mass diffusion can exceed 10% of the divergence effect. However, for short-time-scale prediction, for example, 5 days, the unresolved scales are on the order of 100 km, and turbulent diffusion is about 0.1% of the divergence effect. Because inertial effects are small in the dynamics of the sea ice pack, diffusive momentum transfer can be disregarded.

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We contrast attempts to introduce what were seen as sophisticated Western-style human resource management (HRM) systems into two Russian oil companies – a joint venture with a Western multinational corporation (TNK-BP) and a wholly Russian-owned company (Yukos). The drivers for Western hegemony within the joint venture, heavily influenced by expatriates and the established HRM processes introduced by the Western parent, were counteracted to a significant degree by the Russian spetsifika – the peculiarly Russian way of thinking and doing things. In contrast, developments were absorbed faster in the more authoritarian Russian-owned company. The research adds to the theoretical debate about international knowledge transfer and provides detailed empirical data to support our understanding of the effect of both organizational and cultural context on the knowledge-transfer mechanisms of local and multinational companies. As the analysis is based on the perspective of senior local nationals, we also address a relatively under-researched area in the international HRM literature which mostly relies on empirical data collected from expatriates and those based solely in multinational headquarters.

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Policy makers are in broad agreement that demand response should play a major role in EU electricity systems and provide much needed future system flexibility. Yet, little demand response has been forthcoming in member states to date. This paper identifies some of the technical potential for demand response, based on empirical data from one UK demand aggregator. Half-hourly electricity readings of demand during normal operation and during response events have been analysed for different industry and service sectors. We review these findings in the context of ongoing EU policy developments with particular focus on the role appropriate arrangements to enhance the available resource. We conclude that in some sectors appropriate policy and regulation could triple the available response capacity and thereby lead to stronger commercial uptake of demand response.

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During the last decades, several windstorm series hit Europe leading to large aggregated losses. Such storm series are examples of serial clustering of extreme cyclones, presenting a considerable risk for the insurance industry. Clustering of events and return periods of storm series for Germany are quantified based on potential losses using empirical models. Two reanalysis data sets and observations from German weather stations are considered for 30 winters. Histograms of events exceeding selected return levels (1-, 2- and 5-year) are derived. Return periods of historical storm series are estimated based on the Poisson and the negative binomial distributions. Over 4000 years of general circulation model (GCM) simulations forced with current climate conditions are analysed to provide a better assessment of historical return periods. Estimations differ between distributions, for example 40 to 65 years for the 1990 series. For such less frequent series, estimates obtained with the Poisson distribution clearly deviate from empirical data. The negative binomial distribution provides better estimates, even though a sensitivity to return level and data set is identified. The consideration of GCM data permits a strong reduction of uncertainties. The present results support the importance of considering explicitly clustering of losses for an adequate risk assessment for economical applications.

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Briefing phase interactions between clients and designers are recognized as social engagements, characterized by communicative sign use, where conceptual ideas are gradually transformed into potential design solutions. A semiotic analysis of briefing communications between client stakeholders and designers provides evidence of the significance and importance of stakeholder interpretation and understanding of design, empirical data being drawn from a qualitative study of NHS hospital construction projects in the UK. It is contended that stakeholders engage with a project through communicative signs and artefacts of design, referencing personal cognitive knowledge in acts of interpretation that may be different from those of designers and externally appointed client advisers. Such interpretations occur in addition to NHS client and design team efforts to ‘engage’ with and ‘understand’ stakeholders using a variety of methods. Social semiotic theorizations indicate how narrative strategies motivate the formulation of signs and artefacts in briefing work, the role of sign authors and sign readers being elucidated as a result. Findings are contextualized against current understandings of briefing communications and stakeholder management practices, a more socially attuned understanding of briefing countering some of the process-led improvement models that have characterized much of the post-Egan report literature. A stakeholder interpretation model is presented as one potential method to safeguard against unforeseen interpretations occurring, the model aligning with the proposal for a more measured recognition of how designs can trigger interpretations among client stakeholders.

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The purpose of this paper is to report on the facilities available, organisation of, and staff attitudes to early years outdoor education from schools within the south east of England, focusing on provision for children aged three to five. One component of the successful education of the child involves providing an ‘environment for learning’, including the facilities, layout and routines. This paper presents findings concerning the type and variety of facilities available outside; the various styles of organisation of the space; staff attitudes about: their roles, their aims for the environment, children’s behaviour and learning, and perceived drawbacks to practice. This paper draws on empirical data collected from schools within the University of Reading partnership. The findings suggest that although all early years settings must adhere to the statutory framework there are a range of facilities available, and there are a number of ways this environment is organised. Further there appears to be uncertainty about the adult role outside and the aims for activities. The conclusions drawn indicate that staff do not appear to be linking their aims for outdoor education to the facilities provided or to their actions outside. This means there is not a clear link between what staff provide outside and the declared ambitions for learning. This study is important as all educators need to be certain about their aims for education to ensure best outcomes for children. The implications of these findings for early years teachers are that they need to be able to articulate their aims for outdoor education and to provide the correct facilities to achieve these aims. Finally this study was undertaken to raise debate, posit questions and to ascertain the parameters for further research about the early years outdoor environment.

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Understanding the effects of individual organisms on material cycles and energy fluxes within ecosystems is central to predicting the impacts of human-caused changes on climate, land use, and biodiversity. Here we present a theory that integrates metabolic (organism-based bottom-up) and systems (ecosystem-based top-down) approaches to characterize how the metabolism of individuals affects the flows and stores of materials and energy in ecosystems. The theory predicts how the average residence time of carbon molecules, total system throughflow (TST), and amount of recycling vary with the body size and temperature of the organisms and with trophic organization. We evaluate the theory by comparing theoretical predictions with outputs of numerical models designed to simulate diverse ecosystem types and with empirical data for real ecosystems. Although residence times within different ecosystems vary by orders of magnitude—from weeks in warm pelagic oceans with minute phytoplankton producers to centuries in cold forests with large tree producers—as predicted, all ecosystems fall along a single line: residence time increases linearly with slope = 1.0 with the ratio of whole-ecosystem biomass to primary productivity (B/P). TST was affected predominantly by primary productivity and recycling by the transfer of energy from microbial decomposers to animal consumers. The theory provides a robust basis for estimating the flux and storage of energy, carbon, and other materials in terrestrial, marine, and freshwater ecosystems and for quantifying the roles of different kinds of organisms and environments at scales from local ecosystems to the biosphere.

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Theory predicts the emergence of generalists in variable environments and antagonistic pleiotropy to favour specialists in constant environments, but empirical data seldom support such generalist–specialist trade-offs. We selected for generalists and specialists in the dung fly Sepsis punctum (Diptera: Sepsidae) under conditions that we predicted would reveal antagonistic pleiotropy and multivariate trade-offs underlying thermal reaction norms for juvenile development. We performed replicated laboratory evolution using four treatments: adaptation at a hot (31 °C) or a cold (15 °C) temperature, or under regimes fluctuating between these temperatures, either within or between generations. After 20 generations, we assessed parental effects and genetic responses of thermal reaction norms for three correlated life-history traits: size at maturity, juvenile growth rate and juvenile survival. We find evidence for antagonistic pleiotropy for performance at hot and cold temperatures, and a temperature-mediated trade-off between juvenile survival and size at maturity, suggesting that trade-offs associated with environmental tolerance can arise via intensified evolutionary compromises between genetically correlated traits. However, despite this antagonistic pleiotropy, we found no support for the evolution of increased thermal tolerance breadth at the expense of reduced maximal performance, suggesting low genetic variance in the generalist–specialist dimension.

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Aims There is potential for altered plant-soil feedback (PSF) to develop in human-modified ecosystems but empirical data to test this idea are limited. Here, we compared the PSF operating in jarrah forest soil restored after bauxite mining in Western Australia with that operating in unmined soil. Methods Native seedlings of jarrah (Eucalyptus marginata), acacia (Acacia pulchella), and bossiaea (Bossiaea ornata) were grown in unmined and restored soils to measure conditioning of chemical and biological properties as compared with unplanted control soils. Subsequently, acacia and bossiaea were grown in soils conditioned by their own or by jarrah seedlings to determine the net PSF. Results In unmined soil, the three plant species conditioned the chemical properties but had little effect on the biological properties. In comparison, jarrah and bossiaea conditioned different properties of restored soil while acacia did not condition this soil. In unmined soil, neutral PSF was observed, whereas in restored soil, negative PSF was associated with acacia and bossiaea. Conclusions Soil conditioning was influenced by soil context and plant species. The net PSF was influenced by soil context, not by plant species and it was different in restored and unmined soils. The results have practical implications for ecosystem restoration after human activities.

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This chapter seeks to add to the study of innovation diffusion as enacted within the UK construction sector. Whereas using relevant theoretical frames as touch points, the chapter maps out challenges associated with understanding innovation diffusion within the UK construction sector. Central to the argument developed here is just how diverse the UK construction sector is, resulting in the need to focus upon a specific constituent perspective within the sector. It is argued that constituents of the UK construction sector experience the reality of innovation diffusion differently. The chosen focus here is medium-size and typically regionally based construction firms rather than the big guns, because statistics continually demonstrate that this group of smaller firms undertake more than 80% of the sector’s output. As is pointed out in other chapters in the present volume, and as argued theoretically in the industrial network perspective of chapter 7, firms do not innovate in a vacuum. Innovation and diffusion occur within networks of firms typically around a project. A framework drawing upon empirical data is provided to additional insight on the process and the interconnections. It is argued here that the unit of analysis or level of understanding termed the firm can actually be fairly unhelpful for understanding innovation and its manifestation and diffusion within the broader UK construction sector, because this occurs across networks of firms.

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The UK government is mandating the use of building information modelling (BIM) in large public projects by 2016. As a result, engineering firms are faced with challenges related to embedding new technologies and associated working practices for the digital delivery of major infrastructure projects. Diffusion of innovations theory is used to investigate how digital innovations diffuse across complex firms. A contextualist approach is employed through an in-depth case study of a large, international engineering project-based firm. The analysis of the empirical data, which was collected over a four-year period of close interaction with the firm, reveals parallel paths of diffusion occurring across the firm, where both the innovation and the firm context were continually changing. The diffusion process is traced over three phases: centralization of technology management, standardization of digital working practices, and globalization of digital resources. The findings describe the diffusion of a digital innovation as multiple and partial within a complex social system during times of change and organizational uncertainty, thereby contributing to diffusion of innovations studies in construction by showing a range of activities and dynamics of a non-linear diffusion process.

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Offsite pesticide losses in tropical mountainous regions have been little studied. One example is measuring pesticide drift soil deposition, which can support pesticide risk assessment for surface water, soil, bystanders, off target plants and fauna. This is considered a serious gap, given the evidence of pesticide-related poisoning in those regions. Empirical data of drift deposition of a pesticide surrogate, Uranine tracer, within one of the highest potato producing regions in Colombia, characterized by small plots and mountain orography, is presented. High drift values encountered in our study reflect the actual spray conditions using handled knapsack sprayers. Comparison between measured and predicted drift values using three existing empirical equations showed important underestimation. However, after their optimization based on measured drift information, the equations showed a strong predictive power for this study area and the study conditions. The most suitable curve to assess mean relative drift was the IMAG calculator after optimization.

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How is the notion of public interest operationalised in the regulatory practices of the International Public Sector Accounting Standards Board (IPSASB)? A fundamental objective in setting international accounting standards for both the private and public sector is to serve the ‘public interest’. Who or what constitutes ‘public interest’ however remains a highly complex and controversial issue. Private sector financial reporting research posits that users (of financial information) are used as a proxy for the ‘public’ and users are further refined to current and potential investors - a small proportion of the public. The debates surrounding public interest are even more contentious in public sector financial reporting which deals with ‘public’ (tax payers’) money. In our study we use Bourdieu’s notion of semi-homogenous fields to show how autonomous and heteronomous pressures from the epistemic community of the accounting profession and political/government interests compete for the right to define the public interest and determine how (by what accounting solutions) this interest is best served. This is a theoretical study grounded in the analysis of empirical data from interviews with the board members of the IPSASB. The main contribution of the paper is to further our understanding of the perceptions of the main decision makers from the ‘inner regulatory circle’ with regards to the problematic construct of public interest. The main findings suggest a paternal and un-reflexive attitude of the board members leading to the conclusion that the public have no real voice in these matters.

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The paper examines the process of bank internationalisation and explores how banks become international organisations and what this involves. It also makes an assessment of the significance of their international operations and determines whether banks are truly global organisations. The empirical data are based on the 60 largest banks in the world and content analysis is used to categorise the information into the eight international strategies of Atamer, Calori, Gustavsson, and Menguzzato-Boulard [Internationalisation strategies. In R. Calori, T. Atamer, & P. Nunes (Eds.), The dynamics of international competition – from practice to theory, strategy series (pp. 162–206). London: Sage (2000)] and Bryan, Fraser, Oppenheim, and Rall [Race for the World strategies to build a great global firm. Boston, MA: Harvard Business School Press (1999)]. The findings suggest that the majority of banks focus on countries or geographic regions in which they have some sort of cultural or economic affinity. Moreover, apart from a relatively small number of very large banks, they are international rather than truly global organisations.