15,892 research outputs found

    Optimal Moments for the Analysis of Peculiar Velocity Surveys

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    We present a new method for the analysis of peculiar velocity surveys which removes contributions to velocities from small scale, nonlinear velocity modes while retaining information about large scale motions. Our method utilizes Karhunen--Lo\`eve methods of data compression to construct a set of moments out of the velocities which are minimally sensitive to small scale power. The set of moments are then used in a likelihood analysis. We develop criteria for the selection of moments, as well as a statistic to quantify the overall sensitivity of a set of moments to small scale power. Although we discuss our method in the context of peculiar velocity surveys, it may also prove useful in other situations where data filtering is required.Comment: 25 Pages, 3 figures. Submitted to Ap

    Study of guidance techniques for aerial application of agricultural compounds

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    Candidate systems were identified for evaluation of suitability in meeting specified accuracy requirements for a swath guidance system in an agriculture aircraft. Further examination reduced the list of potential candidates to a single category, i.e., transponder type systems, for detailed evaluation. Within this category three systems were found which met the basic accuracy requirements of the work statement. The Flying Flagman, the Electronic Flagging and the Raydist Director System. In addition to evaluating the systems against the specified requirements, each system was compared with the other two systems on a relative basis. The conclusions supported by the analyses show the Flying Flagman system to be the most suitable system currently available to meet the requirements

    B743: Primary Health Care and the Developmentally Disabled: An Analysis of the Normalization Principle in the State of Maine

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    At the time of publication, there existed an estimated group of 10 million American people defined as developmentally disabled. Stimulated in part by the often observed dehumanizing environment of institutional arrangement for the mentally disabled, the search for more humane treatment and management alternative has pointed in the direction of what has been termed \u27 normalization. In 1969, the Danish Mental Retardation Service defined normalization as \u27\u27 letting the mentally retarded obtain an existence as close to normal as possible. The focus of this study is on barriers to the normalization principle in the provision of primary health care to the developmentally disabled in the State of Maine. Possible barriers include attitudes toward the developmentally disabled, accessibility and quality of community based services, and lack of viable coordination mechanisms. Since 1971, the Maine Department of Mental Health and Corrections has made a concerted effort to encourage services based upon the principle of normalization. As pressures for normalization intensify, it seems warranted that those community-based structures which carry out the concept be examined as to their receptivity and the feasibility of further efforts in this direction. Although the principle of normalization has demonstrated its usefulness and potential, it is not without its limitations (Mesibov 1976). This study made no attempt to examine these limitations of the principle itself.https://digitalcommons.library.umaine.edu/aes_bulletin/1127/thumbnail.jp

    Multiple small monthly doses of dicyandiamide (DCD) did not reduce denitrification in Waikato dairy pasture

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    The effectiveness of multiple small doses of the nitrification inhibitor dicyandiamide (DCD) to decrease denitrification under warm moist conditions was tested in a 1-year field trial on a grazed dairy pasture. DCD was applied approximately every 4 weeks as an aqueous spray onto ten replicate plots 3 days after rotational grazing by dairy cows. Each application was at the rate of 3 kg DCD haā»Ā¹, with a total annual application of 33 kg haā»Ā¹. Denitrification was assessed 5 days after each DCD application using the acetylene block method. At the end of the trial, the rate of degradation of DCD under summer conditions was measured. DCD significantly decreased the mean annual nitrate concentration by about 17%. Denitrification and denitrification enzyme activity were highly variable and no significant effect of DCD in decreasing denitrification was detected. In the summer month of December, DCD degraded rapidly with an estimated half-life of 5 Ā± 3 days (mean and standard deviation)

    Studying Gender in Conference Talks -- data from the 223rd meeting of the American Astronomical Society

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    We present a study on the gender balance, in speakers and attendees, at the recent major astronomical conference, the American Astronomical Society meeting 223, in Washington, DC. We conducted an informal survey, yielding over 300 responses by volunteers at the meeting. Each response included gender data about a single talk given at the meeting, recording the gender of the speaker and all question-askers. In total, 225 individual AAS talks were sampled. We analyze basic statistical properties of this sample. We find that the gender ratio of the speakers closely matched the gender ratio of the conference attendees. The audience asked an average of 2.8 questions per talk. Talks given by women had a slightly higher number of questions asked (3.2Ā±\pm0.2) than talks given by men (2.6Ā±\pm0.1). The most significant result from this study is that while the gender ratio of speakers very closely mirrors that of conference attendees, women are under-represented in the question-asker category. We interpret this to be an age-effect, as senior scientists may be more likely to ask questions, and are more commonly men. A strong dependence on the gender of session chairs is found, whereby women ask disproportionately fewer questions in sessions chaired by men. While our results point to laudable progress in gender-balanced speaker selection, we believe future surveys of this kind would help ensure that collaboration at such meetings is as inclusive as possible.Comment: 4 pages, 5 figures. Comments welcome

    Automated Retrieval of Non-Engineering Domain Solutions to Engineering Problems

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    Organised by: Cranfield UniversityBiological inspiration for engineering design has occurred through a variety of techniques such as creation and use of databases, keyword searches of biological information in natural-language format, prior knowledge of biology, and chance observations of nature. This research focuses on utilizing the reconciled Functional Basis function and flow terms to identify suitable biological inspiration for function based design. The organized search provides two levels of results: (1) associated with verb function only and (2) narrowed results associated with verb-noun (function-flow). A set of heuristics has been complied to promote efficient searching using this technique. An example for creating smart flooring is also presented and discussed.Mori Seiki ā€“ The Machine Tool Compan

    A systematic review of evidence on the impacts of joint decision-making on community wellbeing

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    A systematic review of evidence on the health and wellbeing impacts of community empowerment (joint decision-making) interventions in communities

    Attrition in longitudinal household survey data

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    Longitudinal household data can have considerable advantages over much more widely used cross-sectional data. The collection of longitudinal data, however, may be difficult and expensive. One problem that has concerned many analysts is that sample attrition may make the interpretation of estimates problematic. Such attrition may be particularly severe in areas where there is considerable mobility because of migration between rural and urban areas. Many analysts share the intuition that attrition is likely to be selective on characteristics such as schooling and that high attrition is likely to bias estimates made from longitudinal data. This paper considers the extent of and implications of attrition for three longitudinal household surveys from Bolivia, Kenya, and South Africa that report very high per-year attrition rates between survey rounds. Our estimates indicate that (1) the means for a number of critical outcome and family background variables differ significantly between attritors and nonattritors; (2) a number of family background variables are significant predictors of attrition; but (3) nevertheless, the coefficient estimates for ā€œstandardā€ family background variables in regressions and probit equations for the majority of the outcome variables considered in all three data sets are not affected significantly by attrition. Therefore, attrition apparently is not a general problem for obtaining consistent estimates of the coefficients of interest for most of these outcomes. These results, which are very similar to results for developed economies, suggest that for these outcome variablesā€”despite suggestions of systematic attrition from univariate comparisons between attritors and nonattritors, multivariate estimates of behavioral relations of interest may not be biased due to attrition.Household surveys Methodology ,
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