10,970 research outputs found

    Nonclassicality and the concept of local constraints on the photon number distribution

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    We exploit results from the classical Stieltjes moment problem to bring out the totality of all the information regarding phase insensitive nonclassicality of a state as captured by the photon number distribution p_n. Central to our approach is the realization that n !p_n constitutes the sequence of moments of a (quasi) probability distribution, notwithstanding the fact that p_n can by itself be regarded as a probability distribution. This leads to classicality restrictions on p_n that are local in n involving p_n's for only a small number of consecutive n's, enabling a critical examination of the conjecture that oscillation in p_n is a signature of nonclassicality.Comment: Five pages in revtex with one ps figure included using eps

    Necessary and Sufficient Classicality Conditions on Photon Number Distributions

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    We exploit results on the classical Stieltjes moment problem to obtain completely explicit necessary and sufficient conditions for the photon number distribution p(n) of a radiation field mode to be classical. These conditions are given in two forms - respectively local and global in the individual photon number probabilities. Central to the first approach is the recognition of the important fact that the quantities n!p(n) are moments of a quasiprobability distribution, notwithstanding the fact that p(n)'s can by themselves be considered as a probability distribution over the nonnegative integers. This leads to local classicality conditions involving p(n)'s for only a small number of values of n. This local approach enables us to present detailed quantitative statements on the connection between nonclassicality and oscillations in the photon number distribution. The second approach is in terms of the traditional factorial moments of p(n). Equivalence of the two approaches is established.Comment: 12-pages in revtex with three ps figure included using eps

    Investigating the structure of the autism-spectrum quotient using Mokken scaling

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    Traits similar to those shown in autism spectrum condition (ASC) are apparent in relatives of individuals with ASC, and in the general population without necessarily meeting diagnostic criteria for an ASC. We assess whether the Autism-Spectrum Quotient (AQ), a self-report measure, has hierarchical properties using Mokken scaling. Hierarchical scales allow the presence of a latent trait to be identified by discovering whether and how many specific items form an ordered array along it. Data were collected from 2 groups: (1) people with ASC (n = 449: 240 males, 209 females, M age 35.4 years, SD = 12.8) and (2) university students (n = 943: 465 males, 475 females, M age = 23.0 years, SD = 8.4). A single Mokken scale was obtained in the data from university students and 3 scales were obtained in the data from people with ASC. The scales all showed moderate Mokken scaling properties with the single scale obtained from university students showing weak invariant item ordering and 2 of the scales from people with ASC showing weak invariant item ordering. The AQ formed reliable Mokken scales. There was a large overlap between the scale from the university student sample and the sample with ASC, with the first scale, relating to social interaction, being almost identical. The present study confirms the utility of the AQ as a single instrument that can dimensionalize autistic traits in both university student and clinical samples of ASC, and confirms that items of the AQ are consistently ordered relative to one another

    The role of middle leaders in fostering organizational learning in a state cooperative extension service

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    The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file viewed on (November 13, 2006)Includes bibliographical references.Vita.Thesis (Ed. D.) University of Missouri-Columbia 2005.Dissertations, Academic -- University of Missouri--Columbia -- Educational leadership and policy analysis.This qualitative study explored the nature of organizational learning and the role of regional directors (RDs) and program directors (PDs) as mid-level leaders in fostering organizational learning in one cooperative extension organization. In-depth interviews were conducted with top leaders, middle leaders, campus and regional faculty, and state extension council members. Key findings included organizational learning occurring simultaneously in four dimensions and identification of characteristics of transformative learning. RDs and PDs acted as knowledge activists in their functions as designers, enablers, evaluators, and bridges to foster organizational learning. Critical to organizational learning were relationship building, trust, communication, the process for engaging people in collaborative learning and dialogue as a means for creating a culture of care and the space for learning, and collaboration among RDs and PDs. Barriers to organizational learning involved organizational culture and structure, leader behavior, and the lack of a robust system for accessing the knowledge base

    Using a crop model to account for the effects of local factors on the LCA of sugar beet ethanol in Picardy region, France

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    CT1 ; CT3 ; EnjS1 ; EnjS4 ; Base de données AgroclimInternational audienceThe results of published Life Cycle Assessments (LCAs) of biofuels are characterized by a large variability, arising from the diversity of both biofuel chains and the methodologies used to estimate inventory data. Here, we suggest that the best option to maximize the accuracy of biofuel LCA is to produce local results taking into account the local soil, climatic and agricultural management factors. Methods We focused on a case study involving the production of first-generation ethanol from sugar beet in the Picardy region in Northern France. To account for local factors, we first defined three climatic patterns according to rainfall from a 20-year series of weather data. We subsequently defined two crop rotations with sugar beet as a break crop, corresponding to current practice and an optimized management scenario, respectively. The six combinations of climate types and rotations were run with the process-based model CERES-EGC to estimate crop yields and environmental emissions. We completed the data inventory and compiled the impact assessments using Simapro v.7.1 and Ecoinvent database v2.0. Results Overall, sugar beet ethanol had lower impacts than gasoline for the abiotic depletion, global warming, ozone layer depletion and photochemical oxidation categories. In particular, it emitted between 28 % and 42 % less greenhouse gases than gasoline. Conversely, sugar beet ethanol had higher impacts than gasoline for acidification and eutrophication due to losses of reactive nitrogen in the arable field. Thus, LCA results were highly sensitive to changes in local conditions and management factors. As a result, an average impact figures for a given biofuel chain at regional or national scales may only be indicative within a large uncertainty band. Conclusions Although the crop model made it possible to take local factors into account in the life-cycle inventory, best management practices that achieved high yields while reducing environmental impacts could not be identified. Further modelling developments are necessary to better account for the effects of management practices, in particular regarding the benefits of fertiliser incorporation into the topsoil in terms of nitrogen losses abatement. Supplementary data and modelling developments also are needed to better estimate the emissions of pesticides and heavy metals in the field

    Business Culture Issues in Vietnam: Case Studies

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    What practical issues can arise when doing business in Vietnam? How is Vietnam adapting to the demands of the market economy? In particular, how does a knowledge of Vietnamese business culture, and history, help to clear up misunderstandings – especially involving relations between foreign business people and representatives from Vietnamese business and government? Does the Vietnamese experience have a broader value in the Asian region, where numerous different societies have been seeking a way to engage vigorously in international commerce – yet without losing touch with their own ethical foundations? ... ¶ This volume presents case study material relating to business in Vietnam. It outlines real issues and problems that have arisen – and then seeks to provide a cultural and historical context in which to understand them, and perhaps even solve them

    Towards a generic research data management infrastructure

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    Until recent years, a focused and centralized strategy for the annotation, storage and curation of research data is something that has not been widely considered within academic communities. The majority of research data sits, fragmented, on a variety of disk structures (Desktops, network & external hard drives) and is usually managed locally, with little interest paid to policies governing how it is backed up, disseminated and organized for short or long term reuse. Recognition of how current practices and infrastructure present a barrier to research, has resulted in several recent academic programmes which have focused on developing comprehensive frameworks for the management and curation of research data1-3. Many of these frameworks (such as the Archer suite of e- Research tools1), however, are large and complex, and have an overreliance on new and novel technologies making them unwieldy and difficult to support. The paper discusses the development of a simpler framework for the management of research data through its full lifecycle, allowing users to annotate and structure their research in a secure and backed up environment. The infrastructure is being developed as a pilot system and is expected to work with data from approximately a dozen researchers and manage several Terabytes of data. The technical work is a strand of the MaDAM (Manchester Data Management) project at The University of Manchester which is funded by the JISC Managing Research Data Programme.

    Development of a pilot data management infrastructure for biomedical researchers at University of Manchester – approach, findings, challenges and outlook of the MaDAM Project

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    Management and curation of digital data has been becoming ever more important in a higher education and research environment characterised by large and complex data, demand for more interdisciplinary and collaborative work, extended funder requirements and use of e-infrastructures to facilitate new research methods and paradigms. This paper presents the approach, technical infrastructure, findings, challenges and outlook (including future development within the successor project, MiSS) of the ‘MaDAM: Pilot data management infrastructure for biomedical researchers at University of Manchester’ project funded under the infrastructure strand of the JISC Managing Research Data (JISCMRD) programme. MaDAM developed a pilot research data management solution at the University of Manchester based on biomedical researchers’ requirements, which includes technical and governance components with the flexibility to meet future needs across multiple research groups and disciplines
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