1,086 research outputs found

    Airloads on bluff bodies, with application to the rotor-induced downloads on tilt-rotor aircraft

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    The aerodynamic characteristics of airfoils with several flap configurations were studied theoretically and experimentally in environments that simulate a wing immersed in the downwash of a hovering rotor. Special techniques were developed for correcting and validating the wind tunnel data for large blockage effects, and the test results were used to evaluate two modern blockage effects, and the test results were used to evaluate two modern computational aerodynamics codes. The combined computed and measured results show that improved flap and leading-edge configurations can be designed which will achieve large reductions in the downloads of tilt-rotor aircraft, and thereby improve their hover efficiency

    Using Tembelek (Lantana Camara) Plants as the Basic Materialof Mosquito Repellent Lotion

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    The aims of the research were (1) to find out whether tembelek (lantana camara)plants could be used as the basic material of mosquito repellent lotion; (2) to findput how to make mosquito repellent lotion from tembelek (lantana camara) plants;and (3) to find out whether the mosquito repellent lotion made of tembelek (lantanacamara) plants were safe for the skin.The research method was an experimental one. The research was conducted atSamirono CT IV/160, analysis chemistry laboratory of Ahmad Dahlan University, danlaboratorium Chemix Bantul for five months. The subjects were various kinds of mosquitosand the objects of the research were the tembelek (Lantana camara) plants. Thesteps in this research were (1) observing; (2) experimenting the making of mosquitorepellent lotion; and (3) testing the product.The findings showed that Lantana camara could be used as the material ofmaking the lotion. Three types of lotion were produced with different levels of extracts,namely 10%, 20%, and 30% to get the best formula. Based on the result of theorganoleptic and effectiveness tests in repelling mosquitos, it was found out that thelotion with the extract level of 20% proved to be good in terms of color, smell, texture,safety for the skin and effectiveness in repelling mosquitos

    Wind-tunnel tests of the XV-15 tilt rotor aircraft

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    The XV-15 aircraft was tested in the Ames 40 by 80 Foot Wind Tunnel for preliminary evaluation of aerodynamic and aeroelastic characteristics prior to flight. The tests were undertaken to investigate the aircraft performance, stability, control and structural loads for flight modes from helicopter through transition and airplane mode up to the tunnel capability of 170 knots. Results from these tests are presented

    Incumbency Reconsidered: Prospects, Strategic Entry, and Incumbent Quality in U.S. House Elections

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    Efforts to estimate the magnitude of the incumbency effect in U.S. House elections and assess its political meaning have been complicated by two omitted-variables problems. First, in the absence of an adequate measure of incumbent prospects, estimates of the magnitude of the incumbency effect fail to control for selection effects associated with the decision incumbents make about whether to run for reelection. Strategic incumbents enter races they think they can win and withdraw when they expect to lose. The consequence is an upward bias in estimates of incumbents’ electoral advantages. Second, the normative implications of high reelection rates cannot be assessed without measuring incumbent quality, since a possible explanation for their electoral success is that incumbents are of high quality and doing a good job. We propose a strategy for measuring incumbent prospects and quality, demonstrate the strategic nature of incumbent and challenger entry, re-estimate the incumbency effect, and show that incumbent quality has an impact on electoral outcomes. Our conclusion is that incumbents’ advantages in House elections have been over estimated while the positive basis of incumbent safety is typically under appreciated

    Guidelines for pre-operative cardiac risk assessment and perioperative cardiac management in non-cardiac surgery : the Task Force for Preoperative Cardiac Risk Assessment and Perioperative Cardiac Management in Non-cardiac Surgery of the European Society of Cardiology (ESC) and endorsed by the European Society of Anaesthesiology (ESA)

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    Non-cardiac surgery; Pre-operative cardiac risk assessment; Pre-operative cardiac testing; Pre-operative coronary artery revascularization; Perioperative cardiac management; Renal disease; Pulmonary disease; Neurological disease; Anaesthesiology; Post-operative cardiac surveillanc

    How a Diverse Research Ecosystem Has Generated New Rehabilitation Technologies: Review of NIDILRR’s Rehabilitation Engineering Research Centers

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    Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a “total approach to rehabilitation”, combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970’s, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program

    Candidate Quality and Voter Response in U.S. House Elections

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    We propose and test the implications of a two-dimensional concept of candidate quality in U.S. House elections. Strategic quality is composed of the skills and resources necessary to wage an effective campaign; personal quality is composed of the characteristics most ordinary citizens value in their leaders and representatives, such as personal integrity and dedication to public service. We employ district informants in studies of the 1998 and 2002 congressional elections to measure these qualities in candidates, and we merge mass survey data with the district informant indicators to assess constituents’ awareness and evaluation of House candidates, and voting choice. We find that awareness tends to be responsive to candidates’ strategic quality, and that incumbent evaluation is remarkably responsive to variation in personal quality, even taking into account the quality of challenger emergence. These and other findings appear to support a more positive view of citizen capacity than is common in the congressional elections literature, especially in light of the electoral security of House incumbents

    The rise of consumer health wearables: promises and barriers

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    Will consumer wearable technology ever be adopted or accepted by the medical community? Patients and practitioners regularly use digital technology (e.g., thermometers and glucose monitors) to identify and discuss symptoms. In addition, a third of general practitioners in the United Kingdom report that patients arrive with suggestions for treatment based on online search results. However, consumer health wearables are predicted to become the next “Dr Google.” One in six (15%) consumers in the United States currently uses wearable technology, including smartwatches or fitness bands. While 19 million fitness devices are likely to be sold this year, that number is predicted to grow to 110 million in 2018. As the line between consumer health wearables and medical devices begins to blur, it is now possible for a single wearable device to monitor a range of medical risk factors. Potentially, these devices could give patients direct access to personal analytics that can contribute to their health, facilitate preventive care, and aid in the management of ongoing illness. However, how this new wearable technology might best serve medicine remains unclea
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