5,744 research outputs found

    Free yaw performance of the Mod-0 large horizontal axis 100 kW wind turbine

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    The NASA Mod-0 Large Horizontal Axis 100 kW Wind Turbine was operated in free yaw with an unconed teetered, downwind rotor mounted on a nacelle having 8-1/2 deg tilt. Two series of tests were run, the first series with 19 meter twisted aluminum blades and the second series with 19 meter untwisted steel spar blades with tip control. Rotor speed were nominally 20, 26 and 31 rpm. It was found the nacelle stabilized in free yaw at a yaw angle of between -55 deg to -45 deg was relatively independent of wind speed and was well damped to short term variations in wind direction. Power output of the wind turbine in free yaw, aligned at a large yaw angle, was considerably less than that if the wind turbine were aligned with the wind. For the Mod-0 wind turbine at 26 rpm, the MOSTAB computer code calculations of the free yaw alignment angle and power output compare reasonably well with experimental data. MOSTAB calculations indicate that elimination of tilt and adding coning will improve wind turbine alignment with the wind and that wind shear has a slight detrimental effect on the free yaw alignment angle

    Dynamic Willingness to Pay: An Empirical Specification and Test

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    In a static setting, willingness to pay for an environmental improvement is equal to compensating variation. However, in a dynamic setting characterized by uncertainty, irreversibility, and the potential for learning, willingness to pay may also contain an option value. In this paper, we incorporate the dynamic nature of the value formulation process into a study using a contingent valuation method, designed to measure the value local residents assign to a north-central Iowa lake. Our results show that willingness to pay is highly sensitive to the potential for future learning. Respondents offered the opportunity to delay their purchasing decisions until more information became available were willing to pay significantly less for improved water quality than those who faced a now-or-never decision. The results suggest that welfare analysts should take care to accurately represent the potential for future learning.Clear Lake, contingent valuation, water quality, willingness to pay.

    Carbon Monoxide Screening in Pregnancy: An Evaluation Study of a Plymouth Pilot Intervention

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    This report provides an analysis and evaluation of a National Institute for Health and Care Excellence (NICE) recommended pilot intervention which was designed to identify pregnant women exposed to carbon monoxide due to cigarette smoke and refers them to local stop smoking services (LSSS). The pilot intervention was carried out by community midwives working in two areas of Plymouth. The city has areas of social and health inequalities and the study drew on populations from a socially deprived neighbourhood and a socially affluent area. The pilot was instigated following new NICE guidance recommending that all women attending initial ante natal booking appointments with their community midwives be offered a Carbon Monoxide (CO) breath analyser screening to determine their smoking status and or exposure to other forms of CO. This evaluation study identifies the benefits and barriers associated with the implementation of the CO screening pilot. In particular, our aims were to explore any detrimental impact on the relationship between women and their community midwives, identify the impact on midwives in terms of time and resources, reveal the responses and acceptability or otherwise of the screening as perceived and experienced by the women being asked to participate during the booking appointment and finally to evaluate the success of the intervention overall in relation to the numbers of referrals made to Plymouth’s LSSS. A further aim was explore any differences in the two socio demographic areas. We adopted a mixed methods approach involving four focus group interviews with 23 midwives, a survey posted to the 258 women who attended initial antenatal booking appointments in the study areas, an online version of the survey to ascertain the views and experiences of pregnant women and new mothers nationally and an interrogation of an internet forum discussion board for mothers. A two page questionnaire consisting of 12 questions was designed and posted to women who attended the booking appointment with the midwife during the three month pilot period and the same survey was made available online. Questions were designed to elicit women’s views about the information given by the midwife in relation to the screening, whether they had agreed to participate in the CO screening process, their experiences and views about offering CO screening to pregnant women and their smoking status and those of other household members. Of the 258 questionnaires posted to women who had attended the clinic during the pilot intervention 40 completed responses were returned representing a 15.5% response rate. Only 4 responses were received from the online survey posting but an additional 484 comments posted on the Mumsnet website discussion board were analysed. Our findings show that in general there was a high degree of acceptability for the intervention. Midwives and their clients were generally in support of the screening being offered to all pregnant women. However, this support was dependent on a number of contextual factors. Women wanted to be properly informed about the screening and midwives wanted to be kept informed about the effects of the intervention on women’s smoking cessation. Initial and ongoing training of midwives in utilising the protocol and in instructing women to correct use the monitor was also very important. Trust was revealed to be a very important aspect of the relationship between women and their midwives. Some women felt that the CO screening was being used just to check whether or not they were smokers and some midwives also worried about the possible negative effects the CO screening may have on their relationships with women

    Boundary breathers in the sinh-Gordon model

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    We present an investigation of the boundary breather states of the sinh-Gordon model restricted to a half-line. The classical boundary breathers are presented for a two parameter family of integrable boundary conditions. Restricting to the case of boundary conditions which preserve the \phi --> -\phi symmetry of the bulk theory, the energy spectrum of the boundary states is computed in two ways: firstly, by using the bootstrap technique and subsequently, by using a WKB approximation. Requiring that the two descriptions of the spectrum agree with each other allows a determination of the relationship between the boundary parameter, the bulk coupling constant, and the parameter appearing in the reflection factor derived by Ghoshal to describe the scattering of the sinh-Gordon particle from the boundary.Comment: 16 pages amslate

    Answering the Call: The Story of Community Service and Volunteerism at Sacred Heart University

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    This volume chronicles the history of service and volunteer efforts through personal recollections, newspaper accounts, personal letters, documents and 26 pages of photos that capture Sacred Heart University\u27s commitment to community service. Answering the Call includes chapters on the early years, the El Salvador connection, the 30,000 Hours project, the start of service-learning programs, and current service initiatives in Bridgeport. The book illustrates the University\u27s preferential treatment for the poor and captures its passionate commitment to community servicehttps://digitalcommons.sacredheart.edu/shupress_bks/1006/thumbnail.jp

    Breaking Into Print With Feature Articles

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    If you are anxious to get started as a published writer but don\u27t know where to begin, feature articles for newspapers provide an ideal way to break into print

    Connecticut English Journal, Fall 1969

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    Connecticut English Journal, Spring 1970

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