3,021 research outputs found

    Wind-Tunnel Calibration and Correction Procedures for Three-Dimensional Models

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    Detailed methods are presented for determining the corrections to results from wind-tunnel tests of three-dimensional models for the effects of the model-support system, the nonuniform air flow in the tunnel, and the tunnel walls or jet boundaries. The procedures for determining the corrections are illustrated by equations and the required tests are discussed. Particular attention is given to the parts of the procedures dealing with drag measurements. Two general methods that are used for determining and applying the corrections to force tests are discussed. Some discussion is also included of the correction procedures to be used for wake survey tests. The methods described in this report apply only to tests at subcritical speeds. (author

    Psychological distress and depression in urbanising elderly black persons

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    The findings of a comparative community survey of the socioeconomic, cultural and psychiatric state of elderly black persons in a newly settled township (Khayelitsha - 170 persons) and a long established one (Langa - 195 persons) revealed marked differences. Symptoms of psychological distress, depression and limitation of daily activities were generally more marked in the former and strikingly so among women: 66% had symptoms warranting further investigation and 44% would have been treated for a depressive disorder if seen by a psychiatrist. Extreme poverty existed in both townships but the Khayelitsha subjects were less well educated, their accommodation was poorer, and fewer had old-age pensions. Elderly black women in newly settled townships have therefore been identified as having high priority for psychiatric and social services

    Books

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    Valuable distillations of other people's experiencesHow To Do It. Vol. 3. Pp. x + 203. Illustrated. £9 (including postage by air). London: BMJ. 1990. (Also available from Libriger Book Distributors, Bloemfontein.)Medical dictionaryConcise Medical Dictionary. 3rd ed. Ed. By Elizabeth A. Martin. Pp. 1-759. Oxford: Oxford University Press. 1990.Paediatric cardiologyPrevention in Childhood and Youth of Adult Cardiovascular Diseases: Time for Action. Ed. by WHO Expert Committee. Pp. 1 - 105. Illustrated. Sw. Fr. 12. Geneva: WHO.1990.Contraceptive safety Safety Requirements for Contraceptive Steroids. Ed. by F. Michal. pp. xv - 467. Illustrated. £65,00. Cambridge: Cambridge University Press. 1989.Psychiatry Textbook of Psychiatry. Ed. by P. J. V. Beumont and R. B. Hampshire. Pp. x + 520. Illustrated. PriCe £29,50. Oxford: Blackwell Scientific Publications. 1989

    Books

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    Mental health services - the future New Directions for Mental Health Services. Ed. by C. A. Taube, D. Mechanic and A. A. Hohmann. pp. xii + 324. Illustrated. Rl72,SO. USA: Hemisphere Publishing Corporation. 1990.Clinical and Neuropsychological Aspects of Closed Head Injury. Ed. by J. T. E. Richardson. pp. xi + 351. Illustrated. R13l,lO. London: Taylor & Francis. 1990.Studies in Health Economics 13: Do Expanded Home Care Services Reduce Costs? Ed. by J. H. Sommer. pp. 57. Illustrated. SFr. 8,50. Basle: Pharma Information. 1990. Clinical Epidemiology and Biostatistics: A Primer for Clinical Investigators and Decision-makers. Ed. by Michael S. Kramer. pp. xii + 286. Illustrated. DM 76. Berlin: Springer-Verlag. 1989.Food: What's in it for You? Ed. by Anne Bryce. pp. 320. lllusrrated. Cape Town: Don Nelson. 1990

    Optimizing Exterior Lighting Illuminance and Spectrum for Human, Environmental, and Economic Factors.

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    With the recent widespread adoption of LED lighting in outdoor areas, numerous concerns have been raised about the potential for harmful effects on humans, animals, plants, and the night sky. These stem from the high blue light content of some LED bulbs and an incentive to increase lighting levels caused by higher efficiency and lower costs. While new lighting installations are often described as environmentally friendly due to their energy efficiency, factors such as light pollution are often neglected or not given enough weight. This research focuses on optimizing the design of exterior lighting for human, environmental, and economic factors using a multi-criteria decision analysis. Based on data in the literature and survey research, illuminance and spectrum alternatives were scored relative to each other using the analytic hierarchy process and multi-attribute utility theory. The findings of this study support the use of artificial illumination at levels similar to a full moon (0.01 fc) and a warm white spectrum (2700K or 2200K), with amber LED becoming a better choice if its energy efficiency and cost effectiveness improve in the future. This methodology can be used in the future as a framework for lighting design optimization in different settings

    Caring for the caregiver: Why policy must shift from addressing needs to enabling caregivers to flourish

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    Policies supporting caregivers (“caregiver policies”) are limited in the extent to which they meet the needs of those who care for others. Where policies do exist, they focus on relieving the burdens associated with caring or the needs of the person they care for, rather than consider the holistic needs of the caregiver that would enable them to flourish. We argue that the established approach to caregiver policies reflects a policy failure, requiring a reassessment of current practice related to caregiver support. Often, caregiver policies target the care recipient rather than the caregiver's needs. Through a consultative exercise, we identified five areas of need that existing caregiver policies touch upon. Yet current approaches remain piecemeal and inadequate in a global context. Caregiver policies should not just relieve burden to the extent that caregivers can continue in the role, but they should support caregivers to flourish, and future work may benefit from drawing on related frameworks from positive psychology, such as the PERMA™ model; this is important for both policymakers and researchers

    Children accept information from incongruent speakers when the context explains the communicative incongruence

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    The final publication is available at Elsevier via http://dx.doi.org/https://doi.org/10.1016/j.cogdev.2019.100813. © 2019. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Past work has shown that children are less likely to solicit information from speakers who use incongruent communicative cues (i.e., demonstrate an emotion nonverbally that differs from the emotional valence of the words) versus those who use congruent cues. The present study explored whether school-age children show flexibility in their decisions to avoid incongruent speakers based on the situational context and speakers’ awareness of the context. Older children (9–10 years old), but not younger children (7–8 years old), demonstrated this flexibility. Within a speaker reliability paradigm, incongruent speakers were more likely to be solicited for information when the situational context rendered their affect more appropriate. Moreover, older children showed appreciation for the speakers’ perspective; they were more likely to solicit information from incongruent speakers when the speaker was aware (versus unaware) of the context. Such findings demonstrate the growth in children’s ability to integrate various cues when judging information sources across the school-age years.Funder 1, This research was supported by a Social Sciences and Humanities Research Council Standard Research Grant awarded to EN

    Biomedical Support of U.S. Extravehicular Activity

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    The world's first extravehicular activity (EVA) was performed by A. A. Leonov on March 18, 1965 during the Russian Voskhod-2 mission. The first US EVA was executed by Gemini IV astronaut Ed White on June 3, 1965, with an umbilical tether that included communications and an oxygen supply. A hand-held maneuvering unit (HHMU) also was used to test maneuverability during the brief EVA; however the somewhat stiff umbilical limited controlled movement. That constraint, plus difficulty returning through the vehicle hatch, highlighted the need for increased thermal control and improved EVA ergonomics. Clearly, requirements for a useful EVA were interrelated with the vehicle design. The early Gemini EVAs generated requirements for suits providing micro-meteor protection, adequate visual field and eye protection from solar visual and infrared radiation, gloves optimized for dexterity while pressurized, and thermal systems capable of protecting the astronaut while rejecting metabolic heat during high workloads. Subsequent Gemini EVAs built upon this early experience and included development of a portable environmental control and life support systems (ECLSS) and an astronaut maneuvering unit. The ECLSS provided a pressure vessel and controller with functional control over suit pressure, oxygen flow, carbon dioxide removal, humidity, and temperature control. Gemini EVA experience also identified the usefulness of underwater neutral buoyancy and altitude chamber task training, and the importance of developing reliable task timelines. Improved thermal management and carbon dioxide control also were required for high workload tasks. With the Apollo project, EVA activity was primarily on the lunar surface; and suit durability, integrated liquid cooling garments, and low suit operating pressures (3.75 pounds per square inch absolute [psia] or 25.8 kilopascal [kPa],) were required to facilitate longer EVAs with ambulation and significant physical workloads with average metabolic rates of 1000 BTU/hr and peaks of up to 2200 BTU/hr. Mobility was further augmented with the Lunar Roving Vehicle. The Apollo extravehicular mobility unit (EMU) was made up of over 15 components, ranging from a biomedical belt for capturing and transmitting biomedical data, urine and fecal containment systems, a liquid cooling garment, communications cap, a modular portable life support system (PLSS), a boot system, thermal overgloves, and a bubble helmet with eye protection. Apollo lunar astronauts performed successful EVAs on the lunar surface from a 5 psia (34.4 kPa) 100% oxygen environment in the Lunar Lander. A maximum of three EVAs were performed on any mission. For Skylab a modified A7LB suit, used for Apollo 15, was selected. The Skylab astronaut life support assembly (ALSA) provided umbilical support through the life support umbilical (LSU) and used open loop oxygen flow, rather than closed-loop as in Apollo missions. Thermal control was provided by liquid water circulated by spacecraft pumps and electrical power also was provided from the spacecraft via the umbilical. The cabin atmosphere of 5 psia (34.4 kPa), 70% oxygen, provided a normoxic atmosphere and because of the very low nitrogen partial pressures, no special protocols were required to protect against decompression sickness (DCS) as was the case with the Apollo spacecraft with a 5 psi, 100% oxygen environment

    New measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission

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    Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many body physics. Unfortunately, the pair correlation function g(r)g(r) inferred from neutron scattering measurements of the differential cross section dσdΩd\sigma \over d\Omega from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43~meV and 16.1~meV on liquid hydrogen at 15.6~K (which is dominated by the parahydrogen component) using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1~meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra non-equilibrium component of orthohydrogen. Liquid parahydrogen is also a widely-used neutron moderator medium, and an accurate knowledge of its slow neutron cross section is essential for the design and optimization of intense slow neutron sources. We describe our measurements and compare them with previous work.Comment: Edited for submission to Physical Review
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