10,910 research outputs found

    Electromagnetic containerless processing requirements and recommended facility concept and capabilities for space lab

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    Containerless melting, reaction, and solidification experiments and processes which potentially can lead to new understanding of material science and production of new or improved materials in the weightless space environment are reviewed in terms of planning for spacelab. Most of the experiments and processes discussed are amenable to the employment of electromagnetic position control and electromagnetic induction or electron beam heating and melting. The spectrum of relevant properties of materials, which determine requirements for a space laboratory electromagnetic containerless processing facility are reviewed. Appropriate distributions and associated coil structures are analyzed and compared on the basis of efficiency, for providing the functions of position sensing, control, and induction heating. Several coil systems are found capable of providing these functions. Exchangeable modular coils in appropriate sizes are recommended to achieve the maximum power efficiencies, for a wide range of specimen sizes and resistivities, in order to conserve total facility power

    Image synthesis for SAR system, calibration and processor design

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    The Point Scattering Method of simulating radar imagery rigorously models all aspects of the imaging radar phenomena. Its computational algorithms operate on a symbolic representation of the terrain test site to calculate such parameters as range, angle of incidence, resolution cell size, etc. Empirical backscatter data and elevation data are utilized to model the terrain. Additionally, the important geometrical/propagation effects such as shadow, foreshortening, layover, and local angle of incidence are rigorously treated. Applications of radar image simulation to a proposed calibrated SAR system are highlighted: soil moisture detection and vegetation discrimination

    Investigation of the preparation of materials in space. Task 4 - Field management for weightless containerless processing Quarterly progress report, 22 Aug. - 31 Oct. 1969

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    Weightless containerless processing for space, electromagnetic position control, force measurements and techniques, and hydrodynamic

    The Qualitative Interview in Psychology and the Study of Social Change: Sexual Identity Development, Minority Stress, and Health in the Generations Study.

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    Interviewing is considered a key form of qualitative inquiry in psychology that yields rich data on lived experience and meaning making of life events. Interviews that contain multiple components informed by specific epistemologies have the potential to provide particularly nuanced perspectives on psychological experience. We offer a methodological model for a multi-component interview that draws upon both pragmatic and constructivist epistemologies to examine generational differences in the experience of identity development, stress, and health among contemporary sexual minorities in the United States. Grounded in theories of life course, narrative, and intersectionality, we designed and implemented a multi-component protocol that was administered among a diverse sample of three generations of sexual minority individuals. For each component, we describe the purpose and utility, underlying epistemology, foundational psychological approach, and procedure, and we provide illustrative data from interviewees. We discuss procedures undertaken to ensure methodological integrity in process of data collection, illustrating the implementation of recent guidelines for qualitative inquiry in psychology. We highlight the utility of this qualitative multi-component interview to examine the way in which sexual minorities of distinct generations have made meaning of significant social change over the past half-century

    Design analysis of levitation facility for space processing applications

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    Containerless processing facilities for the space laboratory and space shuttle are defined. Materials process examples representative of the most severe requirements for the facility in terms of electrical power, radio frequency equipment, and the use of an auxiliary electron beam heater were used to discuss matters having the greatest effect upon the space shuttle pallet payload interfaces and envelopes. Improved weight, volume, and efficiency estimates for the RF generating equipment were derived. Results are particularly significant because of the reduced requirements for heat rejection from electrical equipment, one of the principal envelope problems for shuttle pallet payloads. It is shown that although experiments on containerless melting of high temperature refractory materials make it desirable to consider the highest peak powers which can be made available on the pallet, total energy requirements are kept relatively low by the very fast processing times typical of containerless experiments and allows consideration of heat rejection capabilities lower than peak power demand if energy storage in system heat capacitances is considered. Batteries are considered to avoid a requirement for fuel cells capable of furnishing this brief peak power demand

    Observations of celestial X-ray sources above 20 keV with the high-energy scintillation spectrometer on board OSO 8

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    High-energy X-ray spectra of the Crab Nebula, Cyg- XR-1, and Cen A were determined from observations with the scintillation spectrometer on board the OSO-8 satellite, launched in June, 1975. Each of these sources was observed over two periods of 8 days or more, enabling a search for day-to-day and year to year variations in the spectral and temporal characteristics of the X-ray emission. No variation in the light curve of the Crab pulsar was found from observations which span a 15-day period in March 1976, with demonstrable phase stability. Transitions associated with the binary phase of Cyg XR-1 and a large change in the emission from Con A are reported

    Determining the effects of cattle grazing treatments on Yosemite toads (Anaxyrus [=Bufo] canorus) in montane meadows.

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    Amphibians are experiencing a precipitous global decline, and population stability on public lands with multiple uses is a key concern for managers. In the Sierra Nevada Mountains (California, USA), managers have specifically identified livestock grazing as an activity that may negatively affect Yosemite toads due to the potential overlap of grazing with toad habitat. Grazing exclusion from Yosemite toad breeding and rearing areas and/or entire meadows have been proposed as possible management actions to alleviate the possible impact of cattle on this species. The primary objective of this study was to determine if different fencing treatments affect Yosemite toad populations. We specifically examined the effect of three fencing treatments on Yosemite toad breeding pool occupancy, tadpoles, and young of the year (YOY). Our hypothesis was that over the course of treatment implementation (2006 through 2010), Yosemite toad breeding pool occupancy and early life stage densities would increase within two fencing treatments relative to actively grazed meadows due to beneficial changes to habitat quality in the absence of grazing. Our results did not support our hypothesis, and showed no benefit to Yosemite toad presence or early life stages in fenced or partially fenced meadows compared to standard USDA Forest Service grazing levels. We found substantial Yosemite toad variation by both meadow and year. This variation was influenced by meadow wetness, with water table depth significant in both the tadpole and YOY models

    Detection of high energy X-rays from the galactic center region

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    Observations of the galactic center region made with the high energy X-ray detector on OSO-8 are discussed. A strong hard X-ray which was detected during these observations from the vicinity of the galactic center are examined. The counting rate spectrum and the photon number spectrum of the flux are determined. Comparisons with the high energy X-ray fluxes observed from sources in the region by others are discussed

    Targeting sexual health services in primary care: a systematic review of the psychosocial correlates of adverse sexual health outcomes reported in probability surveys of women of reproductive age

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    BACKGROUND: Women using primary care vary in need for sexually transmitted infections (STIs) testing and contraception. Psychosocial correlates of these needs may be useful for targeting services. We undertook a systematic review to identify psychosocial correlates of STI acquisition, unplanned pregnancy (UP), abortion and risky sexual behaviours in general population samples of women of reproductive age. METHODS: We searched bibliographic databases for probability surveys of women aged 16-44years in the European Union, USA, Canada, Australia, UK or New Zealand undertaken January 1994-January 2014. RESULTS: Eleven papers were included. Unplanned pregnancy was associated with smoking, depression, being single and sexual debut <16years. Abortion was associated with lack of closeness to parents, leaving home at an early age, and relationship break-up. Multiple partnerships were associated with intensity of marijuana and alcohol use, and smoking. STI diagnosis was associated with relationship break-up and younger partners. Non-use of contraception was associated with smoking, obesity, relationship status, sedentary lifestyles, fatalistic pregnancy attitudes and lower alcohol use. Condom non-use was higher (at first sex) with partners 5+years older and lower (at last sex) in less stable partnerships. CONCLUSION: Psychosocial variables, particularly relationship status and smoking, may help identify women in primary care for STI testing and contraception advice and supply
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