Science.gov

Sample records for adequately powered studies

  1. DARHT -- an adequate EIS: A NEPA case study

    SciTech Connect

    Webb, M.D.

    1997-08-01

    In April 1996 the US District Court in Albuquerque ruled that the Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility Environmental Impact Statement (EIS), prepared by the Los Alamos Area Office, US Department of Energy (DOE), was adequate. The DARHT EIS had been prepared in the face of a lawsuit in only 10 months, a third of the time usually allotted for a DOE EIS, and for only a small fraction of the cost of a typical DOE EIS, and for only a small fraction of the cost of a typical DOE EIS. It subject was the first major facility to be built in decades for the DOE nuclear weapons stockpile stewardship program. It was the first EIS to be prepared for a proposal at DOE`s Los Alamos National Laboratory since 1979, and the first ever prepared by the Los Alamos Area Office. Much of the subject matter was classified. The facility had been specially designed to minimize impacts to a nearby prehistoric Native American ruin, and extensive consultation with American Indian Pueblos was required. The week that the draft EIS was published Laboratory biologists identified a previously unknown pair of Mexican spotted owls in the immediate vicinity of the project, bringing into play the consultation requirements of the Endangered Species Act. In spite of these obstacles, the resultant DARHT EIS was reviewed by the court and found to meet all statutory and regulatory requirements; the court praised the treatment of the classified material which served as a basis for the environmental analysis.

  2. Are the Standards Adequate for Organizing African American Studies Resources?

    ERIC Educational Resources Information Center

    Washington, Dorothy Ann

    Standards of bibliographic organization often are inadequate for those libraries with extensive African American studies collections or those with active user groups. This essay identifies areas where the standards are least effective. The experiences of the staff at the Schomburg Center for Research in Black Culture, The New York Public Library,…

  3. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... with one or more controls to provide a quantitative evaluation of drug effects. The protocol and the... for special circumstances. Examples include studies in which the effect of the new animal drug is...

  4. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... with one or more controls to provide a quantitative evaluation of drug effects. The protocol and the... for special circumstances. Examples include studies in which the effect of the new animal drug is...

  5. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... with one or more controls to provide a quantitative evaluation of drug effects. The protocol and the... for special circumstances. Examples include studies in which the effect of the new animal drug is...

  6. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... with one or more controls to provide a quantitative evaluation of drug effects. The protocol and the... for special circumstances. Examples include studies in which the effect of the new animal drug is...

  7. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... with one or more controls to provide a quantitative evaluation of drug effects. The protocol and the... for special circumstances. Examples include studies in which the effect of the new animal drug is...

  8. Emotional Experiences of Obese Women with Adequate Gestational Weight Variation: A Qualitative Study

    PubMed Central

    Faria-Schützer, Débora Bicudo; Surita, Fernanda Garanhani de Castro; Alves, Vera Lucia Pereira; Vieira, Carla Maria; Turato, Egberto Ribeiro

    2015-01-01

    Background As a result of the growth of the obese population, the number of obese women of fertile age has increased in the last few years. Obesity in pregnancy is related to greater levels of anxiety, depression and physical harm. However, pregnancy is an opportune moment for the intervention of health care professionals to address obesity. The objective of this study was to describe how obese pregnant women emotionally experience success in adequate weight control. Methods and Findings Using a qualitative design that seeks to understand content in the field of health, the sample of subjects was deliberated, with thirteen obese pregnant women selected to participate in an individual interview. Data was analysed by inductive content analysis and includes complete transcription of the interviews, re-readings using suspended attention, categorization in discussion topics and the qualitative and inductive analysis of the content. The analysis revealed four categories, three of which show the trajectory of body care that obese women experience during pregnancy: 1) The obese pregnant woman starts to think about her body;2) The challenge of the diet for the obese pregnant woman; 3) The relation of the obese pregnant woman with the team of antenatal professionals. The fourth category reveals the origin of the motivation for the change: 4) The potentializing factors for change: the motivation of the obese woman while pregnant. Conclusions During pregnancy, obese women are more in touch with themselves and with their emotional conflicts. Through the transformations of their bodies, women can start a more refined self-care process and experience of the body-mind unit. The fear for their own and their baby's life, due to the risks posed by obesity, appears to be a great potentializing factor for change. The relationship with the professionals of the health care team plays an important role in the motivational support of the obese pregnant woman. PMID:26529600

  9. The rat adequately reflects human responses to exercise in blood biochemical profile: a comparative study

    PubMed Central

    Goutianos, Georgios; Tzioura, Aikaterini; Kyparos, Antonios; Paschalis, Vassilis; Margaritelis, Nikos V; Veskoukis, Aristidis S; Zafeiridis, Andreas; Dipla, Konstantina; Nikolaidis, Michalis G; Vrabas, Ioannis S

    2015-01-01

    Animal models are widely used in biology and the findings of animal research are traditionally projected to humans. However, recent publications have raised concerns with regard to what extent animals and humans respond similar to physiological stimuli. Original data on direct in vivo comparison between animals and humans are scarce and no study has addressed this issue after exercise. We aimed to compare side by side in the same experimental setup rat and human responses to an acute exercise bout of matched intensity and duration. Rats and humans ran on a treadmill at 86% of maximal velocity until exhaustion. Pre and post exercise we measured 30 blood chemistry parameters, which evaluate iron status, lipid profile, glucose regulation, protein metabolism, liver, and renal function. ANOVA indicated that almost all biochemical parameters followed a similar alteration pattern post exercise in rats and humans. In fact, there were only 2/30 significant species × exercise interactions (in testosterone and globulins), indicating different responses to exercise between rats and humans. On the contrary, the main effect of exercise was significant in 15/30 parameters and marginally nonsignificant in other two parameters (copper, P = 0.060 and apolipoprotein B, P = 0.058). Our major finding is that the rat adequately mimics human responses to exercise in those basic blood biochemical parameters reported here. The physiological resemblance of rat and human blood responses after exercise to exhaustion on a treadmill indicates that the use of blood chemistry in rats for exercise physiology research is justified. PMID:25677548

  10. Are Substance Use Prevention Programs More Effective in Schools Making Adequate Yearly Progress? A Study of Project ALERT

    ERIC Educational Resources Information Center

    Clark, Heddy Kovach; Ringwalt, Chris L.; Shamblen, Stephen R.; Hanley, Sean M.; Flewelling, Robert L.

    2011-01-01

    This exploratory study sought to determine if a popular school-based drug prevention program might be effective in schools that are making adequate yearly progress (AYP). Thirty-four schools with grades 6 through 8 in 11 states were randomly assigned either to receive Project ALERT (n = 17) or to a control group (n = 17); of these, 10 intervention…

  11. Are Power Analyses Reported with Adequate Detail? Evidence from the First Wave of Group Randomized Trials Funded by the Institute of Education Sciences

    ERIC Educational Resources Information Center

    Spybrook, Jessaca

    2008-01-01

    This study examines the reporting of power analyses in the group randomized trials funded by the Institute of Education Sciences from 2002 to 2006. A detailed power analysis provides critical information that allows reviewers to (a) replicate the power analysis and (b) assess whether the parameters used in the power analysis are reasonable.…

  12. Cost Effectiveness of Screening Colonoscopy Depends on Adequate Bowel Preparation Rates – A Modeling Study

    PubMed Central

    Kingsley, James; Karanth, Siddharth; Revere, Frances Lee

    2016-01-01

    Background Inadequate bowel preparation during screening colonoscopy necessitates repeating colonoscopy. Studies suggest inadequate bowel preparation rates of 20–60%. This increases the cost of colonoscopy for our society. Aim The aim of this study is to determine the impact of inadequate bowel preparation rate on the cost effectiveness of colonoscopy compared to other screening strategies for colorectal cancer (CRC). Methods A microsimulation model of CRC screening strategies for the general population at average risk for CRC. The strategies include fecal immunochemistry test (FIT) every year, colonoscopy every ten years, sigmoidoscopy every five years, or stool DNA test every 3 years. The screening could be performed at private practice offices, outpatient hospitals, and ambulatory surgical centers. Results At the current assumed inadequate bowel preparation rate of 25%, the cost of colonoscopy as a screening strategy is above society’s willingness to pay (<$50,000/QALY). Threshold analysis demonstrated that an inadequate bowel preparation rate of 13% or less is necessary before colonoscopy is considered more cost effective than FIT. At inadequate bowel preparation rates of 25%, colonoscopy is still more cost effective compared to sigmoidoscopy and stool DNA test. Sensitivity analysis of all inputs adjusted by ±10% showed incremental cost effectiveness ratio values were influenced most by the specificity, adherence, and sensitivity of FIT and colonoscopy. Conclusions Screening colonoscopy is not a cost effective strategy when compared with fecal immunochemical test, as long as the inadequate bowel preparation rate is greater than 13%. PMID:27936028

  13. Power subsystem automation study

    NASA Technical Reports Server (NTRS)

    Tietz, J. C.; Sewy, D.; Pickering, C.; Sauers, R.

    1984-01-01

    The purpose of the phase 2 of the power subsystem automation study was to demonstrate the feasibility of using computer software to manage an aspect of the electrical power subsystem on a space station. The state of the art in expert systems software was investigated in this study. This effort resulted in the demonstration of prototype expert system software for managing one aspect of a simulated space station power subsystem.

  14. Power system commonality study

    NASA Astrophysics Data System (ADS)

    Littman, Franklin D.

    1992-07-01

    A limited top level study was completed to determine the commonality of power system/subsystem concepts within potential lunar and Mars surface power system architectures. A list of power system concepts with high commonality was developed which can be used to synthesize power system architectures which minimize development cost. Examples of potential high commonality power system architectures are given in this report along with a mass comparison. Other criteria such as life cycle cost (which includes transportation cost), reliability, safety, risk, and operability should be used in future, more detailed studies to select optimum power system architectures. Nineteen potential power system concepts were identified and evaluated for planetary surface applications including photovoltaic arrays with energy storage, isotope, and nuclear power systems. A top level environmental factors study was completed to assess environmental impacts on the identified power system concepts for both lunar and Mars applications. Potential power system design solutions for commonality between Mars and lunar applications were identified. Isotope, photovoltaic array (PVA), regenerative fuel cell (RFC), stainless steel liquid-metal cooled reactors (less than 1033 K maximum) with dynamic converters, and in-core thermionic reactor systems were found suitable for both lunar and Mars environments. The use of SP-100 thermoelectric (TE) and SP-100 dynamic power systems in a vacuum enclosure may also be possible for Mars applications although several issues need to be investigated further (potential single point failure of enclosure, mass penalty of enclosure and active pumping system, additional installation time and complexity). There are also technical issues involved with development of thermionic reactors (life, serviceability, and adaptability to other power conversion units). Additional studies are required to determine the optimum reactor concept for Mars applications. Various screening

  15. Structural and functional MRI study of the brain, cognition and mood in long-term adequately treated Hashimoto's thyroiditis.

    PubMed

    Quinque, Eva M; Karger, Stefan; Arélin, Katrin; Schroeter, Matthias L; Kratzsch, Jürgen; Villringer, Arno

    2014-04-01

    The current study investigated neuropsychological and underlying structural and functional brain alterations in long-term adequately treated patients with Hashimoto's thyroiditis in order to examine much discussed residual complaints in patients in relation to possible long-term neural alterations with a specific interest in the underlying autoimmune process. Eighteen patients with treated hypothyroidism due to Hashimoto's thyroiditis (mean age 32, range 18-54 years; two males; mean treatment duration 4.4 years) and 18 healthy matched control subjects underwent 3-Tesla magnetic resonance imaging (MRI). Voxel-based morphometry was used to investigate grey matter density, resting-state functional MRI to analyse the brain connectivity of areas known to be altered in hypothyroidism and event-related functional MRI to examine brain activity during associative memory encoding. Neuropsychological assessment included memory, working memory, psychomotor speed and attention. We previously reported subclinically reduced mood in this study population and investigated its neural correlates here. Thyroid stimulating hormone, free triiodthyronine, free thyroxine and thyroid peroxidase antibodies were measured in serum. We did not find cognitive deficits or alterations in grey matter density, functional connectivity or associative memory-related brain activity in comparison to the control group and cognition was unrelated to thyroid serum measures in the patient group. Thyroid peroxidase antibodies in the patient group correlated with increased grey matter density in right amygdala and enhanced connectivity between subcallosal and parahippocampal areas. Treatment duration was associated with brain structure in frontal and occipital cortex and connectivity between left amygdala and frontal cortex. Mood correlated with brain areas associated with distinct functional networks, but not with those most prominently affected in depression. In conclusion, no cognitive or neural

  16. Study to Determine Adequate Margins in Radiotherapy Planning for Esophageal Carcinoma by Detailing Patterns of Recurrence After Definitive Chemoradiotherapy

    SciTech Connect

    Button, Michael R. Morgan, Carys A.; Croydon, Elizabeth S.; Roberts, S. Ashley; Crosby, Thomas D.L.

    2009-03-01

    Purpose: To ascertain the adequacy of radiotherapy (RT) margins by studying the relapse patterns after definitive chemoradiotherapy for carcinoma of the esophagus. Methods and Materials: We performed a retrospective study assessing the first site of disease relapse after definitive chemoradiotherapy that included four 3-weekly cycles of cisplatin and continuous infusion 5-fluorouracil, with conformal RT (50 Gy in 25 fractions) concurrent with Cycles 3 and 4. The RT planning target volume was the endoscopic ultrasonography/computed tomography-defined gross tumor volume with 1.5-cm lateral and 3-cm superoinferior margins. Results: A total of 145 patients were included. Their average age was 65.4 years, 45% had adenocarcinoma, 61% had lower third esophageal tumors, and 75% had Stage III-IVA disease. After RT, of 142 patients, 85 (60%) had evidence of relapse at a median follow-up of 18 months. The relapse was local (within the RT field) in 55; distant (metastatic) in 13, and a combination of local and distant in 14. The local relapse rates were not influenced by tumor stage, lymph node status, or disease length. Three patients developed a relapse in regions adjacent to the RT fields; however, it is unlikely that larger field margins would have been clinically acceptable or effective in these cases. The median overall survival was 15 months. Conclusion: The gross tumor volume-planning target volume margins in this study appeared adequate. Future efforts to improve outcomes using definitive chemoradiotherapy should be directed toward reducing the high rates of in-field and distant relapses.

  17. Rotorcraft contingency power study

    NASA Technical Reports Server (NTRS)

    Hirschkron, R.; Haynes, J. F.; Goldstein, D. N.; Davis, R. H.

    1984-01-01

    Twin helicopter engines are often sized by the power requirement of a safe mission completion after the failure of one of the two engines. This study was undertaken for NASA Lewis by General Electric Co. to evaluate the merits of special design features to provide a 2-1/2 Contingency Power rating, permitting an engine size reduction. The merits of water injection, turbine cooling airflow modulation, throttle push, and a propellant auxiliary power plant were evaluated using military Life Cycle Cost (LCC) and commercial helicopter Direct Operating Cost (DOC) merit factors in a rubber engine and a rubber aircraft scenario.

  18. Do special constables in London feel that they are adequately prepared to meet their first aid responsibilities? A qualitative study

    PubMed Central

    Meakin, Richard

    2016-01-01

    Objective This study's aims were to explore the views of special constables in the London metropolitan police force concerning their obligations and skills as first aiders. Background The metropolitan police force provides police officers to act as first responders to emergency calls made by the public. Special constables act with the same powers and responsibility as police officers and are required to deal with incidents involving medical emergencies. Setting West London Police Station. Participants Fifteen special constables entered and completed the study. Methods and Outcome Measures A qualitative study involving semistructured interviews, participant observation, and reflective work. The outcome measures were the themes derived from the ‘thematic framework approach’ to analysis. Results Four main themes were identified. (1) ‘Our responsibility?’—Special constables felt they had a responsibility, but were unsure of the origin of this responsibility, with many feeling it stemmed from public expectation. (2) ‘Confidence’—Special constables had mixed feelings regarding their confidence in first aid scenarios and many felt that more could be done to improve their confidence. (3) ‘Training needs’—Many felt the current training system was lacking in several ways including regularity, teaching and content. (4) ‘Personal first aid knowledge’—Special constables were disappointed with their past performances. Conclusions Owing to the small size of this study, the conclusions are limited; however, if the findings are confirmed by larger studies, they suggest the need to improve the confidence of special constables in first aid situations. PMID:26826155

  19. Power Plant Replacement Study

    SciTech Connect

    Reed, Gary

    2010-09-30

    This report represents the final report for the Eastern Illinois University power plant replacement study. It contains all related documentation from consideration of possible solutions to the final recommended option. Included are the economic justifications associated with the chosen solution along with application for environmental permitting for the selected project for construction. This final report will summarize the results of execution of an EPC (energy performance contract) investment grade audit (IGA) which lead to an energy services agreement (ESA). The project includes scope of work to design and install energy conservation measures which are guaranteed by the contractor to be self‐funding over its twenty year contract duration. The cost recovery is derived from systems performance improvements leading to energy savings. The prime focus of this EPC effort is to provide a replacement solution for Eastern Illinois University’s aging and failing circa 1925 central steam production plant. Twenty‐three ECMs were considered viable whose net impact will provide sufficient savings to successfully support the overall project objectives.

  20. Power Plant Replacement Study

    SciTech Connect

    Reed, Gary

    2010-09-30

    This report represents the final report for the Eastern Illinois University power plant replacement study. It contains all related documentation from consideration of possible solutions to the final recommended option. Included are the economic justifications associated with the chosen solution along with application for environmental permitting for the selected project for construction. This final report will summarize the results of execution of an EPC (energy performance contract) investment grade audit (IGA) which lead to an energy services agreement (ESA). The project includes scope of work to design and install energy conservation measures which are guaranteed by the contractor to be self-funding over its twenty year contract duration. The cost recovery is derived from systems performance improvements leading to energy savings. The prime focus of this EPC effort is to provide a replacement solution for Eastern Illinois University’s aging and failing circa 1925 central steam production plant. Twenty-three ECMs were considered viable whose net impact will provide sufficient savings to successfully support the overall project objectives.

  1. Power Plant Replacement Study

    SciTech Connect

    Reed, Gary

    2010-09-30

    This report represents the final report for the Eastern Illinois University power plant replacement study. It contains all related documentation from consideration of possible solutions to the final recommended option. Included are the economic justifications associated with the chosen solution along with application for environmental permitting for the selected project for construction. This final report will summarize the results of execution of an EPC (energy performance contract) investment grade audit (IGA) which lead to an energy services agreement (ESA). The project includes scope of work to design and install energy conservation measures which are guaranteed by the contractor to be self-funding over its twenty year contract duration. The cost recovery is derived from systems performance improvements leading to energy savings. The prime focus of this EPC effort is to provide a replacement solution for Eastern Illinois University's aging and failing circa 1925 central steam production plant. Twenty-three ECMs were considered viable whose net impact will provide sufficient savings to successfully support the overall project objectives.

  2. Power subsystem automation study

    NASA Technical Reports Server (NTRS)

    Imamura, M. S.; Moser, R. L.; Veatch, M.

    1983-01-01

    Generic power-system elements and their potential faults are identified. Automation functions and their resulting benefits are defined and automation functions between power subsystem, central spacecraft computer, and ground flight-support personnel are partitioned. All automation activities were categorized as data handling, monitoring, routine control, fault handling, planning and operations, or anomaly handling. Incorporation of all these classes of tasks, except for anomaly handling, in power subsystem hardware and software was concluded to be mandatory to meet the design and operational requirements of the space station. The key drivers are long mission lifetime, modular growth, high-performance flexibility, a need to accommodate different electrical user-load equipment, onorbit assembly/maintenance/servicing, and potentially large number of power subsystem components. A significant effort in algorithm development and validation is essential in meeting the 1987 technology readiness date for the space station.

  3. Violence as an Under-Recognized Barrier to Women's Realization of Their Right to Adequate Food and Nutrition: Case Studies From Georgia and South Africa.

    PubMed

    Bellows, Anne C; Lemke, Stefanie; Jenderedjian, Anna; Scherbaum, Veronika

    2015-10-01

    This article addresses under-acknowledged barriers of structural violence and discrimination that interfere with women's capacity to realize their human rights generally, and their right to adequate food and nutrition in particular. Case studies from Georgia and South Africa illustrate the need for a human rights-based approach to food and nutrition security that prioritizes non-discrimination, public participation, and self-determination. These principles are frustrated by different types of structural violence that, if not seriously addressed, pose multiple barriers to women's economic, public, and social engagement.

  4. Adequate Wound Care and Use of Bed Nets as Protective Factors against Buruli Ulcer: Results from a Case Control Study in Cameroon

    PubMed Central

    Landier, Jordi; Boisier, Pascal; Fotso Piam, Félix; Noumen-Djeunga, Blanbin; Simé, Joseph; Wantong, Fidèle Gaetan; Marsollier, Laurent; Fontanet, Arnaud; Eyangoh, Sara

    2011-01-01

    Background Buruli ulcer is an infectious disease involving the skin, caused by Mycobacterium ulcerans. Its exact transmission mechanism remains unknown. Several arguments indicate a possible role for insects in its transmission. A previous case-control study in the Nyong valley region in central Cameroon showed an unexpected association between bed net use and protection against Buruli ulcer. We investigated whether this association persisted in a newly discovered endemic Buruli ulcer focus in Bankim, northwestern Cameroon. Methodology/Principal Findings We conducted a case-control study on 77 Buruli ulcer cases and 153 age-, gender- and village-matched controls. Participants were interviewed about their activities and habits. Multivariate conditional logistic regression analysis identified systematic use of a bed net (Odds-Ratio (OR) = 0.4, 95% Confidence Interval [95%CI] = [0.2–0.9], p-value (p) = 0.04), cleansing wounds with soap (OR [95%CI] = 0.1 [0.03–0.3], p<0.0001) and growing cassava (OR [95%CI] = 0.3 [0.2–0.7], p = 0.005) as independent protective factors. Independent risk factors were bathing in the Mbam River (OR [95%CI] = 6.9 [1.4–35], p = 0.02) and reporting scratch lesions after insect bites (OR [95%CI] = 2.7 [1.4–5.4], p = 0.004). The proportion of cases that could be prevented by systematic bed net use was 32%, and by adequate wound care was 34%. Conclusions/Significance Our study confirms that two previously identified factors, adequate wound care and bed net use, significantly decreased the risk of Buruli ulcer. These associations withstand generalization to different geographic, climatic and epidemiologic settings. Involvement of insects in the household environment, and the relationship between wound hygiene and M. ulcerans infection should now be investigated. PMID:22087346

  5. Confidence in the Knowledge Base of English Language Learners Studying Science: Using Agency to Compensate for the Lack of Adequate Linguistic Identity

    NASA Astrophysics Data System (ADS)

    Hayes, Aneta L.; Mansour, Nasser

    2016-01-01

    Changes in the cultural and linguistic environments of learners are often associated with identity shifts. The aim of this study was to explore what identity shifts occur when science students from Bahraini national schools transition to an international university. The role of two aspects of learner identity—that is, English proficiency and science background knowledge, was examined in this study. Focus groups and semi-structured interviews were conducted with students and with university lecturers. The analysis suggested three conceptual themes of (1) reliance on science knowledge, (2) the auxiliary role of professional language and (3) adequacy of student learning strategies, demonstrating what subjective meanings the participants ascribe to the interplay between science knowledge and linguistic ability. The findings suggest that despite the lack of adequate linguistic attributes, the students are still able to successfully learn science in the context of language change. It is also implied that through strategically utilising their academic background in science, students preserve their identity as successful learners from school through to university. We conclude that agency plays a separate role in transition and is not a sole function of identity. We also contest the idea of language as a necessary attribute of one's identity as it was perceived by our participants to be an advantage and an auxiliary tool rather than a requirement.

  6. Funding the Formula Adequately in Oklahoma

    ERIC Educational Resources Information Center

    Hancock, Kenneth

    2015-01-01

    This report is a longevity, simulational study that looks at how the ratio of state support to local support effects the number of school districts that breaks the common school's funding formula which in turns effects the equity of distribution to the common schools. After nearly two decades of adequately supporting the funding formula, Oklahoma…

  7. Accelerating Monte Carlo power studies through parametric power estimation.

    PubMed

    Ueckert, Sebastian; Karlsson, Mats O; Hooker, Andrew C

    2016-04-01

    Estimating the power for a non-linear mixed-effects model-based analysis is challenging due to the lack of a closed form analytic expression. Often, computationally intensive Monte Carlo studies need to be employed to evaluate the power of a planned experiment. This is especially time consuming if full power versus sample size curves are to be obtained. A novel parametric power estimation (PPE) algorithm utilizing the theoretical distribution of the alternative hypothesis is presented in this work. The PPE algorithm estimates the unknown non-centrality parameter in the theoretical distribution from a limited number of Monte Carlo simulation and estimations. The estimated parameter linearly scales with study size allowing a quick generation of the full power versus study size curve. A comparison of the PPE with the classical, purely Monte Carlo-based power estimation (MCPE) algorithm for five diverse pharmacometric models showed an excellent agreement between both algorithms, with a low bias of less than 1.2 % and higher precision for the PPE. The power extrapolated from a specific study size was in a very good agreement with power curves obtained with the MCPE algorithm. PPE represents a promising approach to accelerate the power calculation for non-linear mixed effect models.

  8. Sample size estimation and power analysis for clinical research studies

    PubMed Central

    Suresh, KP; Chandrashekara, S

    2012-01-01

    Determining the optimal sample size for a study assures an adequate power to detect statistical significance. Hence, it is a critical step in the design of a planned research protocol. Using too many participants in a study is expensive and exposes more number of subjects to procedure. Similarly, if study is underpowered, it will be statistically inconclusive and may make the whole protocol a failure. This paper covers the essentials in calculating power and sample size for a variety of applied study designs. Sample size computation for single group mean, survey type of studies, 2 group studies based on means and proportions or rates, correlation studies and for case-control for assessing the categorical outcome are presented in detail. PMID:22870008

  9. Study on photovoltaic power system on ships

    SciTech Connect

    Katagi, Takeshi; Fujii, Yoshimi; Nishikawa, Eiichi; Hashimoto, Takeshi

    1995-11-01

    This paper presents the application of photovoltaic power systems to ships. Two types of leisure or fishing boats powered by photovoltaics are designed. The boats described are single hull and catamaran type with twin hulls. The design of a new electric power system using a photovoltaic power system in a harbor ship having 20 tons is also proposed. The results of this study show that the photovoltaic power system can apply to small ships.

  10. Lunar nuclear power feasibility study

    NASA Technical Reports Server (NTRS)

    Erdman, C. A.; Tran, T.

    1984-01-01

    Based on review of literature and on limited examination of nuclear power systems now proposed for space applications, a nuclear fission reactor powered system should be seriously considered as the first large (order of 50 kWe or greater) power system to be placed on a lunar base. With relatively minor modifications, the major one being addition of a cooled side shield, the proposed 100 kWe product of the SP-100 Program could be adapted for use on a lunar base.

  11. Power module Data Management System (DMS) study

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Computer trades and analyses of selected Power Module Data Management Subsystem issues to support concurrent inhouse MSFC Power Study are provided. The charts which summarize and describe the results are presented. Software requirements and definitions are included.

  12. Serum thyroglobulin reference intervals in regions with adequate and more than adequate iodine intake.

    PubMed

    Wang, Zhaojun; Zhang, Hanyi; Zhang, Xiaowen; Sun, Jie; Han, Cheng; Li, Chenyan; Li, Yongze; Teng, Xiaochun; Fan, Chenling; Liu, Aihua; Shan, Zhongyan; Liu, Chao; Weng, Jianping; Teng, Weiping

    2016-11-01

    The purpose of this study was to establish normal thyroglobulin (Tg) reference intervals (RIs) in regions with adequate and more than adequate iodine intake according to the National Academy of Clinical Biochemistry (NACB) guidelines and to investigate the relationships between Tg and other factors.A total of 1317 thyroid disease-free adult subjects (578 men, 739 nonpregnant women) from 2 cities (Guangzhou and Nanjing) were enrolled in this retrospective, observational study. Each subject completed a questionnaire and underwent physical and ultrasonic examination. Serum Tg, thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), Tg antibody (TgAb), and urinary iodine concentration (UIC) were measured. Reference groups were established on the basis of TSH levels: 0.5 to 2.0 and 0.27 to 4.2 mIU/L.The Tg RIs for Guangzhou and Nanjing were 1.6 to 30.0 and 1.9 to 25.8 ng/mL, respectively. No significant differences in Tg were found between genders or among different reference groups. Stepwise linear regression analyses showed that TgAb, thyroid volume, goiter, gender, age, and TSH levels were correlated with Tg.In adults from regions with adequate and more than adequate iodine intake, we found that Tg may be a suitable marker of iodine status; gender-specific Tg RI was unnecessary; there was no difference between Tg RIs in regions with adequate and more than adequate iodine intake; and the TSH criterion for selecting the Tg reference population could follow the local TSH reference rather than 0.5 to 2.0 mIU/L.

  13. Serum thyroglobulin reference intervals in regions with adequate and more than adequate iodine intake

    PubMed Central

    Wang, Zhaojun; Zhang, Hanyi; Zhang, Xiaowen; Sun, Jie; Han, Cheng; Li, Chenyan; Li, Yongze; Teng, Xiaochun; Fan, Chenling; Liu, Aihua; Shan, Zhongyan; Liu, Chao; Weng, Jianping; Teng, Weiping

    2016-01-01

    Abstract The purpose of this study was to establish normal thyroglobulin (Tg) reference intervals (RIs) in regions with adequate and more than adequate iodine intake according to the National Academy of Clinical Biochemistry (NACB) guidelines and to investigate the relationships between Tg and other factors. A total of 1317 thyroid disease-free adult subjects (578 men, 739 nonpregnant women) from 2 cities (Guangzhou and Nanjing) were enrolled in this retrospective, observational study. Each subject completed a questionnaire and underwent physical and ultrasonic examination. Serum Tg, thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), Tg antibody (TgAb), and urinary iodine concentration (UIC) were measured. Reference groups were established on the basis of TSH levels: 0.5 to 2.0 and 0.27 to 4.2 mIU/L. The Tg RIs for Guangzhou and Nanjing were 1.6 to 30.0 and 1.9 to 25.8 ng/mL, respectively. No significant differences in Tg were found between genders or among different reference groups. Stepwise linear regression analyses showed that TgAb, thyroid volume, goiter, gender, age, and TSH levels were correlated with Tg. In adults from regions with adequate and more than adequate iodine intake, we found that Tg may be a suitable marker of iodine status; gender-specific Tg RI was unnecessary; there was no difference between Tg RIs in regions with adequate and more than adequate iodine intake; and the TSH criterion for selecting the Tg reference population could follow the local TSH reference rather than 0.5 to 2.0 mIU/L. PMID:27902589

  14. 21 CFR 1404.900 - Adequate evidence.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false Adequate evidence. 1404.900 Section 1404.900 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.900 Adequate evidence. Adequate evidence means information sufficient...

  15. 21 CFR 1404.900 - Adequate evidence.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Adequate evidence. 1404.900 Section 1404.900 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.900 Adequate evidence. Adequate evidence means information sufficient...

  16. Fluorescence quenching of beta-carboline alkaloids in micellar media. A study to select the adequate surfactant to use in analytical techniques.

    PubMed

    Martín, Laura; Olives, Ana I; del Castillo, Benito; Martín, M Antonia

    2005-01-01

    The study of fluorescence quenching of the fluorophores allows the localization of the alkaloids (harmane and harmine) in the micelles (SDS, CTAB, Brij-35) to be established. In aqueous micellar solutions (SDS and Brij-35) at pH 13.0, emission corresponding to the neutral or zwitterionic forms can be observed. In the presence of CTAB (pH = 13.0) it was possible to observe the emission of anionic form. These species are not present in buffered aqueous solutions at these pH values. Bromide ion was added to the different surfactant solutions and the quenching effect was studied according to the Stern-Volmer equation. In the presence of SDS the quenching effect is considerably reduced compared to the aqueous solutions without surfactants, while for Brij-35 micelles were similar to those observed in homogeneous aqueous solution. For CTAB micelles a notable fluorescence quenching was observed for the different pH values studied. The fluorescence quenching studies show that the neutral species are associated inside the micelles, instead of the ionic species (cationic, zwitterionic or anionic) remaining on the surface of the micelles. The anionic surface of SDS micelles prevents the quenching effect by anionic quenchers for both neutral and charged species.

  17. Adequate Compensation for a Permanent Change of Station Move: A Study Comparing the Policies of the Military, Civil Service, and Private Sector.

    DTIC Science & Technology

    1980-03-01

    home for five days while their household goods are packed and picked up, the house is cleaned by a professional cleaning service, and a final inspection ...OF THE MILITARY, CIVIL SERVICE, AND PRIVATE SECTOR by Gregory Lee Hansen __. and __ Dwight Warner Handforth March 1980 L LJ Thesis Advisor: EA. Finnkp...Change o Masr esis Station Mrove: A Study cmpaing the Policiesarh1 of the Military, Civil Service, and Private a. PROMISNG 00G. REPORT uU6860 6. CONTRACT

  18. Cyanide is an adequate agonist of the plant hormone ethylene for studying signalling of sensor kinase ETR1 at the molecular level.

    PubMed

    Bisson, Melanie M A; Groth, Georg

    2012-06-01

    The plant hormone ethylene is involved in many developmental processes and responses to environmental stresses in plants. Although the elements of the signalling cascade and the receptors operating the ethylene pathway have been identified, a detailed understanding of the molecular processes related to signal perception and transfer is still lacking. Analysis of these processes using purified proteins in physical, structural and functional studies is complicated by the gaseous character of the plant hormone. In the present study, we show that cyanide, a π-acceptor compound and structural analogue of ethylene, is a suitable substitute for the plant hormone for in vitro studies with purified proteins. Recombinant ethylene receptor protein ETR1 (ethylene-resistant 1) showed high level and selective binding of [(14)C]cyanide in the presence of copper, a known cofactor in ethylene binding. Replacement of Cys(65) in the ethylene-binding domain by serine dramatically reduced binding of radiolabelled cyanide. In contrast with wild-type ETR1, autokinase activity of the receptor is not reduced in the ETR1-C65S mutant upon addition of cyanide. Additionally, protein-protein interaction with the ethylene signalling protein EIN2 (ethylene-insensitive 2) is considerably sustained by cyanide in wild-type ETR1, but is not affected in the mutant. Further evidence for the structural and functional equivalence of ethylene and cyanide is given by the fact that the ethylene-responsive antagonist silver, which is known to allow ligand binding but prevent intrinsic signal transduction, also allows specific binding of cyanide, but shows no effect on autokinase activity and ETR1-EIN2 interaction.

  19. Is Single-Strand Conformation Polymorphism Analysis of the Full 5′ Untranslated Region an Adequate Approach To Study Hepatitis C Virus Quasispecies Distribution? ▿

    PubMed Central

    Vera-Otarola, Jorge; Barría, María Inés; León, Ursula; Carvallo, Pilar; Soza, Alejandro; López-Lastra, Marcelo

    2009-01-01

    Single-strand conformation polymorphism (SSCP) analysis is used by many laboratories to study the quasispecies distribution of the hepatitis C virus (HCV). Here we question the validity of this experimental approach, as conclusions are drawn from the analysis of the migration patterns of two ssDNA molecules and not from RNA. Using previously characterized mutants of the HCV 5′ untranslated regions, we show that contrary to what has been predicted, SSCP migration patterns of DNA amplicons with differences in their nucleotide sequences generated from the full 5′ UTR of HCV are not necessarily unique. PMID:19553315

  20. Is single-strand conformation polymorphism analysis of the full 5' untranslated region an adequate approach to study hepatitis C virus quasispecies distribution?

    PubMed

    Vera-Otarola, Jorge; Barría, María Inés; León, Ursula; Carvallo, Pilar; Soza, Alejandro; López-Lastra, Marcelo

    2009-09-01

    Single-strand conformation polymorphism (SSCP) analysis is used by many laboratories to study the quasispecies distribution of the hepatitis C virus (HCV). Here we question the validity of this experimental approach, as conclusions are drawn from the analysis of the migration patterns of two ssDNA molecules and not from RNA. Using previously characterized mutants of the HCV 5' untranslated regions, we show that contrary to what has been predicted, SSCP migration patterns of DNA amplicons with differences in their nucleotide sequences generated from the full 5' UTR of HCV are not necessarily unique.

  1. Are ciprofloxacin dosage regimens adequate for antimicrobial efficacy and prevention of resistance? Pseudomonas aeruginosa bloodstream infection in elderly patients as a simulation case study.

    PubMed

    Cazaubon, Yoann; Bourguignon, Laurent; Goutelle, Sylvain; Martin, Olivier; Maire, Pascal; Ducher, Michel

    2015-12-01

    The aim of this work was to define the optimal dosage (OD) of ciprofloxacin in order to prevent the emergence of bacterial resistance of Pseudomonas aeruginosa in a geriatric population with a bloodstream infection. A thousand pharmacokinetic profiles were simulated with a ciprofloxacin pharmacokinetic model from the literature. Three dosing regimens were tested for five days: once daily (QD), twice daily (BID), and thrice daily (TID). First of all, effective dosages (ED) of ciprofloxacin were defined as those achieving a target AUC24 /MIC ≥ 125. Then, these ED were simulated in order to calculate the percentage of time spent within the mutant selection window (TMSW ) and to select optimal dosage (OD) defined as those achieving TMSW ≤ 20%. Based on the AUC24 /MIC, for low MICs (0.125 μg/mL), all dosing regimens recommended by French guidelines were effective. For intermediate MICs (0.25 and 0.5 μg/mL), simulated doses higher than those recommended were needed to achieve the efficacy target. About prevention of resistance for low MICs, dosages recommended were only effective in patients with creatinine clearance (CLCR ) ≥ 60 mL/min. For intermediate MICs, dosages higher than recommended were needed to achieve the optimality target. This study shows that current ciprofloxacin dosing guidelines have not been optimized to prevent the emergence of bacterial resistance, especially in geriatric patients with mild to severe renal impairment. To achieve both efficacy and prevention of resistance, ciprofloxacin dosages greater than those recommended would be needed. Tolerance of such higher doses needs to be evaluated in clinical studies.

  2. No Obesity Paradox-BMI Incapable of Adequately Capturing the Relation of Obesity with All-Cause Mortality: An Inception Diabetes Cohort Study.

    PubMed

    Bozorgmanesh, Mohammadreza; Arshi, Banafsheh; Sheikholeslami, Farhad; Azizi, Fereidoun; Hadaegh, Farzad

    2014-01-01

    Background. To reconcile "the obesity paradox," we tested if (1) the contribution of anthropometric measures to mortality was nonlinear and (2) the confounding of hip circumference contributed to the obesity paradox recently observed among diabetic patients. Methods. We analyzed data of diabetic patients attending a community-based prospective, "Tehran lipid and glucose study." In the mortality analysis, anthropometric measures-body mass index (BMI), waist, and hip circumference-were assessed using Cox models incorporating cubic spline functions. Results. During 12 990 person-years follow-up, BMI levels below 27 and those above 40 kg·m(-2) were associated with increased mortality. When we added waist circumference to the BMI in the multivariate-adjusted model, the steepness of BMI-mortality association curve slope for values below 27 kg·m(-2) increased, whereas the steepness of BMI-mortality association curve slope for values above this threshold decreased. Further adjusting the model for hip circumference, the steepness of the slopes of the association curve moved towards null on both extremes and no associations between BMI and all-cause mortality remained. Conclusion. BMI harbors intermixed positive and negative confounding effects on mortality of waist and hip circumference. Failing to control for the confounding effect of hip circumference may stymie unbiased hazard estimation and render conclusions paradoxical.

  3. Knowledge and Power in Social Studies Education.

    ERIC Educational Resources Information Center

    Cherryholmes, Cleo H.

    This paper addresses the following problem: how do power relationships constrain what counts as knowledge in social studies education and thus constitute the field? By looking at speech acts performed in a given socio-linguistic community one can get insight into discursive practices of that community. The present concern is with power relations…

  4. Development of an analytical tool to study power quality of AC power systems for large spacecraft

    NASA Technical Reports Server (NTRS)

    Kraft, L. Alan; Kankam, M. David

    1991-01-01

    A harmonic power flow program applicable to space power systems with sources of harmonic distortion is described. The algorithm is a modification of the Electric Power Research Institute's HARMFLO program which assumes a three phase, balanced, AC system with loads of harmonic distortion. The modified power flow program can be used with single phase, AC systems. Early results indicate that the required modifications and the models developed are quite adequate for the analysis of a 20 kHz testbed built by General Dynamics Corporation. This is demonstrated by the acceptable correlation of present results with published data. Although the results are not exact, the discrepancies are relatively small.

  5. Development of an analytical tool to study power quality of ac power systems for large spacecraft

    NASA Technical Reports Server (NTRS)

    Kraft, L. A.; Kankam, M. D.

    1991-01-01

    A harmonic power flow program applicable to space power systems with sources of harmonic distortion is described. The algorithm is a modification of Electric Power Research Institute's HARMFLO program which assumes a three-phase, balanced, ac system with loads of harmonic distortion. The modified power flow program can be used with single phase, ac systems. Early results indicate that the required modifications and the models developed are quite adequate for the analysis of a 20-kHz testbed built by General Dynamics Corporation. This is demonstrated by the acceptable correlation of the present results with published data. Although the results are not exact, the discrepancies are relatively small.

  6. Lunar Wireless Power Transfer Feasibility Study

    SciTech Connect

    Freid, Sheldon; Popovic, Zoya; Beckett, David R.; Anderson, Scott R.; Mann, Diana; Walker, Stuart

    2008-03-01

    This study examines the feasibility of a multi-kilowatt wireless radio frequency (RF) power system to transfer power between lunar base facilities. Initial analyses, show that wireless power transfer (WPT) systems can be more efficient and less expensive than traditional wired approaches for certain lunar and terrestrial applications. The study includes evaluations of the fundamental limitations of lunar WPT systems, the interrelationships of possible operational parameters, and a baseline design approach for a notionial system that could be used in the near future to power remote facilities at a lunar base. Our notional system includes state-of-the-art photovoltaics (PVs), high-efficiency microwave transmitters, low-mass large-aperture high-power transmit antennas, high-efficiency large-area rectenna receiving arrays, and reconfigurable DC combining circuitry.

  7. Nuclear Power Options Viability Study. Volume 1. Executive summary

    SciTech Connect

    Trauger, D.B.; White, J.D.; Booth, R.S.; Bowers, H.I.; Braid, R.B.; Cantor, R.A.; Cleveland, J.C.; Delene, J.G.; Gat, U.; Hood, T.C.

    1986-09-01

    Innovative reactor concepts are described and evaluated in accordance with criteria established in the study. The reactors to be studied were selected on the basis of three ground rules: (1) the potential for commercialization between 2000 to 2010, (2) economic competitiveness with coal, and (3) the degree of passive safety in the design. The concepts, classified by coolants, were light water reactors, liquid metal reactors, and high-temperature reactors, and most were of modular design. Although the information available is not adequate for a definitive evaluation of economic competitiveness, all of the concepts appear to be potentially viable in the time frame selected. Public and institutional acceptance of nuclear power was found to be affected primarily by four issues: (1) operational safety, (2) waste handling and disposal, (3) construction and operating costs, and (4) the adequacy of management and regulatory controls.

  8. Studies Probe Power of "Personalization"

    ERIC Educational Resources Information Center

    Sparks, Sarah D.

    2012-01-01

    While "personalization" has become a buzzword in education, it can be hard to determine what really makes a subject relevant to individual children in the classroom. An ongoing series of studies at Southern Methodist University suggests learning students' interests upfront and incorporating them into lessons can get struggling students to try…

  9. 5 CFR 919.900 - Adequate evidence.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Adequate evidence. 919.900 Section 919.900 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 919.900 Adequate...

  10. Trade studies for nuclear space power systems

    NASA Technical Reports Server (NTRS)

    Smith, John M.; Bents, David J.; Bloomfield, Harvey S.

    1991-01-01

    As human visions of space applications expand and as we probe further out into the universe, our needs for power will also expand, and missions will evolve which are enabled by nuclear power. A broad spectrum of missions which are enhanced or enabled by nuclear power sources have been defined. These include Earth orbital platforms, deep space platforms, planetary exploration, and terrestrial resource exploration. The recently proposed Space Exploration Initiative (SEI) to the Moon and Mars has more clearly defined these missions and their power requirements. Presented here are results of recent studies of radioisotope and nuclear reactor energy sources, combined with various energy conversion devices for Earth orbital applications, SEI lunar/Mars rovers, surface power, and planetary exploration.

  11. Trade studies for nuclear space power systems

    NASA Technical Reports Server (NTRS)

    Smith, John M.; Bents, David J.; Bloomfield, Harvey S.

    1991-01-01

    As visions of space applications expand and as probes extend further and further out into the universe, the need for power also expands, and missions evolve which are enabled by nuclear power. A broad spectrum of missions which are enhanced or enabled by nuclear power sources are defined. These include earth orbital platforms, deep space platforms, planetary exploration and extraterrestrial resource exploration. The recently proposed Space Exploration Initiative (SEI) to the moon and Mars has more clearly defined these missions and their power requirements. This paper presents results of recent studies of radioisotope and nuclear-reactor energy sources combined with various energy-conversion devices for earth orbital applications, SEI lunar/Mars rover and surface power, and planetary exploration.

  12. A study of power conditioning and power distribution and components

    NASA Technical Reports Server (NTRS)

    Horton, H. M.; Honnell, M. A.

    1973-01-01

    A comprehensive simulation and analysis performed on the operation of the regulator part of the Charger/Battery/Regulator Module (CBRM) are detailed. The CBRM is utilized as an integral component of the Skylab/Apollo Telescope Mount (ATM) electrical power system and contains a switching mode electronic regulator. Implementing circuit analysis techniques, pertinent voltages and currents are calculated; these, in turn, are incorporated into the regulator system study. Investigation of the turn-on and turn-off times associated with the switching circuitry is performed and an examination is made on these calculations. A simulation model computer program is utilized to generate graphs that relate various CBRM parameters to one another.

  13. Multi-Megawatt Power System Trade Study

    SciTech Connect

    Longhurst, Glen Reed; Schnitzler, Bruce Gordon; Parks, Benjamin Travis

    2002-02-01

    A concept study was undertaken to evaluate potential multi-megawatt power sources for nuclear electric propulsion. The nominal electric power requirement was set at 15 MWe with an assumed mission profile of 120 days at full power, 60 days in hot standby, and another 120 days of full power, repeated several times for 7 years of service. Two configurations examined were (1) a gas-cooled reactor based on the NERVA Derivative design, operating a closed cycle Brayton power conversion system; and (2) a molten metal-cooled reactor based on SP-100 technology, driving a boiling potassium Rankine power conversion system. This study considered the relative merits of these two systems, seeking to optimize the specific mass. Conclusions were that either concept appeared capable of approaching the specific mass goal of 3-5 kg/kWe estimated to be needed for this class of mission, though neither could be realized without substantial development in reactor fuels technology, thermal radiator mass efficiency, and power conversion and distribution electronics systems capable of operating at high temperatures. The gas-Brayton systems showed an apparent specific mass advantage (3.53 vs 6.43 kg/kWe for the baseline cases) under the set of assumptions used, but reconciling differences in conservatism in the design algorithms used would make results much more comparable. Brayton systems eliminate the need to deal with two-phase working fluid flows in the microgravity environment of space.

  14. Multi-megawatt power system trade study

    NASA Astrophysics Data System (ADS)

    Longhurst, Glen R.; Schnitzler, Bruce G.; Parks, Benjamin T.

    2002-01-01

    A concept study was undertaken to evaluate potential multi-megawatt power sources for nuclear electric propulsion. The nominal electric power requirement was set at 15 MWe with an assumed mission profile of 120 days at full power, 60 days in hot standby, and another 120 days of full power, repeated several times for 7 years of service. Two configurations examined were (1) a gas-cooled reactor based on the NERVA Derivative design, operating a closed cycle Brayton power conversion system; and (2) a molten metal-cooled reactor based on SP-100 technology, driving a boiling potassium Rankine power conversion system. This study considered the relative merits of these two systems, seeking to optimize the specific mass. Conclusions were that either concept appeared capable of reaching the specific mass goal of 3-5 kg/kWe estimated to be needed for this class of mission, though neither could be realized without substantial development in reactor fuels technology, thermal radiator mass and volume efficiency, and power conversion and distribution electronics and systems capable of operating at high temperatures. The gas-Brayton system showed a specific mass advantage (3.17 vs 6.43 kg/kWe for the baseline cases) under the set of assumptions used and eliminated the need to deal with two-phase working fluid flows in the microgravity environment of space. .

  15. Solar dynamic power system definition study

    NASA Technical Reports Server (NTRS)

    Wallin, Wayne E.; Friefeld, Jerry M.

    1988-01-01

    The solar dynamic power system design and analysis study compared Brayton, alkali-metal Rankine, and free-piston Stirling cycles with silicon planar and GaAs concentrator photovoltaic power systems for application to missions beyond the Phase 2 Space Station level of technology for all power systems. Conceptual designs for Brayton and Stirling power systems were developed for 35 kWe and 7 kWe power levels. All power systems were designed for 7-year end-of-life conditions in low Earth orbit. LiF was selected for thermal energy storage for the solar dynamic systems. Results indicate that the Stirling cycle systems have the highest performance (lowest weight and area) followed by the Brayton cycle, with photovoltaic systems considerably lower in performance. For example, based on the performance assumptions used, the planar silicon power system weight was 55 to 75 percent higher than for the Stirling system. A technology program was developed to address areas wherein significant performance improvements could be realized relative to the current state-of-the-art as represented by Space Station. In addition, a preliminary evaluation of hardenability potential found that solar dynamic systems can be hardened beyond the hardness inherent in the conceptual designs of this study.

  16. Feasibility Study B-1 Power Controller.

    DTIC Science & Technology

    1979-11-01

    Study performed by the Autonetics Strategic Systems Division ( ASSD ) of Rockwell International on Contract N62269-79-C-0294. The objective of this study...Modify the design of the ASSD B-1 SSPC, Part Number 12880-507-1, to be a 115 Vac quadruple SSPC unit, with a SOSTEL compatible interface. 3.1.2 115 Vac...Primary Power Modifications. The ASSD SSPC Unit, Appendix A, contains four identical PC’s operating from 230 Vac primary power. Referring to Figure 1

  17. Lunar Base Thermoelectric Power Station Study

    NASA Astrophysics Data System (ADS)

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, Gerhard; Brooks, Michael; Heshmatpour, Ben

    2006-01-01

    Under NASA's Project Prometheus, the Nuclear Space Power Systems Program, the Jet Propulsion Laboratory, Pratt & Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) Task, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing, and promising candidates for the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as a lunar base power station where kilowatts of power would be required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this particular mission concept. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed as well as transport issues for this concept. The goal of the study was to review the entire life cycle of the

  18. Lunar Base Thermoelectric Power Station Study

    SciTech Connect

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, Gerhard; Brooks, Michael; Heshmatpour, Ben

    2006-01-20

    Under NASA's Project Prometheus, the Nuclear Space Power Systems Program, the Jet Propulsion Laboratory, Pratt and Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) Task, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing, and promising candidates for the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as a lunar base power station where kilowatts of power would be required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this particular mission concept. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed as well as transport issues for this concept. The goal of the study was to review the entire life cycle of

  19. Multi-Megawatt Power System Trade Study

    SciTech Connect

    Longhurst, Glen Reed; Schnitzler, Bruce Gordon; Parks, Benjamin Travis

    2001-11-01

    As part of a larger task, the Idaho National Engineering and Environmental Laboratory (INEEL) was tasked to perform a trade study comparing liquid-metal cooled reactors having Rankine power conversion systems with gas-cooled reactors having Brayton power conversion systems. This report summarizes the approach, the methodology, and the results of that trade study. Findings suggest that either approach has the possibility to approach the target specific mass of 3-5 kg/kWe for the power system, though it appears either will require improvements to achieve that. Higher reactor temperatures have the most potential for reducing the specific mass of gas-cooled reactors but do not necessarily have a similar effect for liquid-cooled Rankine systems. Fuels development will be the key to higher reactor operating temperatures. Higher temperature turbines will be important for Brayton systems. Both replacing lithium coolant in the primary circuit with gallium and replacing potassium with sodium in the power loop for liquid systems increase system specific mass. Changing the feed pump turbine to an electric motor in Rankine systems has little effect. Key technologies in reducing specific mass are high reactor and radiator operating temperatures, low radiator areal density, and low turbine/generator system masses. Turbine/generator mass tends to dominate overall power system mass for Rankine systems. Radiator mass was dominant for Brayton systems.

  20. Concentrating Solar Power Commercial Application Study

    SciTech Connect

    none,

    2009-10-01

    This report has been prepared in response to section 603(b) of the Energy Independence and Security Act of 2007, (Pub. L. No. 110-140), which states that “…the Secretary of Energy shall transmit to Congress a report on the results of a study on methods to reduce the amount of water consumed by concentrating solar power systems.”

  1. Solar power satellite system definition study. Part 2, volume 4: Microwave power transmission systems

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A slotted waveguide planar array was established as the baseline design for the spaceborne transmitter antenna. Key aspects of efficient energy conversion at both ends of the power transfer link were analyzed and optimized alternate approaches in the areas of antenna and tube design are discussed. An integrated design concept was developed which meets design requirements, observes structural and thermal constraints, exhibits good performance and was developed in adequate depth to permit cost estimating at the subsystem/component level.

  2. Tokamak power systems studies, FY 1985

    SciTech Connect

    Baker, C.C.; Brooks, J.N.; Ehst, D.A.; Smith, D.L.; Sze, D.K.

    1985-12-01

    The Tokamak Power System Studies (TPSS) at ANL in FY-1985 were devoted to exploring innovative design concepts which have the potential for making substantial improvements in the tokamak as a commercial power reactor. Major objectives of this work included improved reactor economics, improved environmental and safety features, and the exploration of a wide range of reactor plant outputs with emphasis on reduced plant sizes compared to STARFIRE. The activities concentrated on three areas: plasma engineering, impurity control, and blanket/first wall/shield technology. 205 refs., 125 figs., 107 tabs.

  3. Asbestos/NESHAP adequately wet guidance

    SciTech Connect

    Shafer, R.; Throwe, S.; Salgado, O.; Garlow, C.; Hoerath, E.

    1990-12-01

    The Asbestos NESHAP requires facility owners and/or operators involved in demolition and renovation activities to control emissions of particulate asbestos to the outside air because no safe concentration of airborne asbestos has ever been established. The primary method used to control asbestos emissions is to adequately wet the Asbestos Containing Material (ACM) with a wetting agent prior to, during and after demolition/renovation activities. The purpose of the document is to provide guidance to asbestos inspectors and the regulated community on how to determine if friable ACM is adequately wet as required by the Asbestos NESHAP.

  4. Lunar base thermoelectric power station study

    NASA Technical Reports Server (NTRS)

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, G.; Brooks, Michael D.; Heshmatpour, Ben

    2006-01-01

    Under NASA's Project Prometheus, the Nuclear Systems Program, the Jet Propulsion Laboratory, Pratt & Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) program, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing and the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as the lunar base power station where kilowatts of power are required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this mission. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed and well as transport issues for this concept. The goal of the study was to review the entire life cycle of the unit to assess its technical problems and technology

  5. 7 CFR 1710.303 - Power cost studies-power supply borrowers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... contracts or revisions to existing contracts, and an analysis of the effects on power costs; (4) Use of... 7 Agriculture 11 2011-01-01 2011-01-01 false Power cost studies-power supply borrowers. 1710.303... AND GUARANTEES Long-Range Financial Forecasts § 1710.303 Power cost studies—power supply borrowers....

  6. 7 CFR 1710.303 - Power cost studies-power supply borrowers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... contracts or revisions to existing contracts, and an analysis of the effects on power costs; (4) Use of... 7 Agriculture 11 2013-01-01 2013-01-01 false Power cost studies-power supply borrowers. 1710.303... AND GUARANTEES Long-Range Financial Forecasts § 1710.303 Power cost studies—power supply borrowers....

  7. 7 CFR 1710.303 - Power cost studies-power supply borrowers.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... contracts or revisions to existing contracts, and an analysis of the effects on power costs; (4) Use of... 7 Agriculture 11 2012-01-01 2012-01-01 false Power cost studies-power supply borrowers. 1710.303... AND GUARANTEES Long-Range Financial Forecasts § 1710.303 Power cost studies—power supply borrowers....

  8. Solar thermal electric power information user study

    SciTech Connect

    Belew, W.W.; Wood, B.L.; Marle, T.L.; Reinhardt, C.L.

    1981-02-01

    The results of a series of telephone interviews with groups of users of information on solar thermal electric power are described. These results, part of a larger study on many different solar technologies, identify types of information each group needed and the best ways to get information to each group. The report is 1 of 10 discussing study results. The overall study provides baseline data about information needs in the solar community. An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from five solar thermal electric power groups of respondents are analyzed: DOE-Funded Researchers, Non-DOE-Funded Researchers, Representatives of Utilities, Electric Power Engineers, and Educators. The data will be used as input to the determination of information products and services the Solar Energy Research Institute, the Solar Energy Information Data Bank Network, and the entire information outreach community should be preparing and disseminating.

  9. Mars power system concept definition study. Volume 1: Study results

    NASA Technical Reports Server (NTRS)

    Littman, Franklin D.

    1994-01-01

    A preliminary top level study was completed to define power system concepts applicable to Mars surface applications. This effort included definition of power system requirements and selection of power systems with the potential for high commonality. These power systems included dynamic isotope, Proton Exchange Membrane (PEM) regenerative fuel cell, sodium sulfur battery, photovoltaic, and reactor concepts. Design influencing factors were identified. Characterization studies were then done for each concept to determine system performance, size/volume, and mass. Operations studies were done to determine emplacement/deployment maintenance/servicing, and startup/shutdown requirements. Technology development roadmaps were written for each candidate power system (included in Volume 2). Example power system architectures were defined and compared on a mass basis. The dynamic isotope power system and nuclear reactor power system architectures had significantly lower total masses than the photovoltaic system architectures. Integrated development and deployment time phasing plans were completed for an example DIPS and reactor architecture option to determine the development strategies required to meet the mission scenario requirements.

  10. Power supply standardization and optimization study

    NASA Technical Reports Server (NTRS)

    Ware, C. L.; Ragusa, E. V.

    1972-01-01

    A comprehensive design study of a power supply for use in the space shuttle and other space flight applications is presented. The design specifications are established for a power supply capable of supplying over 90 percent of the anticipated voltage requirements for future spacecraft avionics systems. Analyses and tradeoff studies were performed on several alternative design approaches to assure that the selected design would provide near optimum performance of the planned applications. The selected design uses a dc-to-dc converter incorporating regenerative current feedback with a time-ratio controlled duty cycle to achieve high efficiency over a wide variation in input voltage and output loads. The packaging concept uses an expandable mainframe capable of accommodating up to six inverter/regulator modules with one common input filter module.

  11. General Electric Unattended Power System Study. Addendum

    DTIC Science & Technology

    1980-05-01

    Only minor, inexpensive changes in the fuel panel, portions of the electrical control panel, and type of burner are required to convert from one type of... converts chemical energy into electrical energy. The capacity of the fuel cell is limited only by the supply of fuel, commonly referred to as the...ESD-TR-80-124 MTR- 3844 GENERAL ELECTRIC UNATTENDED POWER SYSTEM STUDY ADDENDUM BY D.D. BREGENZER MAY 1980 dg:C Prepared for DEPUTY FOR SURVEILLANCE

  12. Oral Calcidiol Is More Effective Than Cholecalciferol Supplementation to Reach Adequate 25(OH)D Levels in Patients with Autoimmune Diseases Chronically Treated with Low Doses of Glucocorticoids: A "Real-Life" Study.

    PubMed

    Ortego-Jurado, Miguel; Callejas-Rubio, José-Luis; Ríos-Fernández, Raquel; González-Moreno, Juan; González Ramírez, Amanda Rocío; González-Gay, Miguel A; Ortego-Centeno, Norberto

    2015-01-01

    Glucocorticoids (GCs) are the cornerstone of the therapy in many autoimmune and inflammatory diseases. However, it is well known that their use is a double edged sword, as their beneficial effects are associated almost universally with unwanted effects, as, for example glucocorticoid-induced osteoporosis (GIO). Over the last years, several clinical practice guidelines emphasize the need of preventing bone mass loss and reduce the incidence of fractures associated with GC use. Calcium and vitamin D supplementation, as adjunctive therapy, are included in all the practice guidelines. However, no standard vitamin D dose has been established. Several studies with postmenopausal women show that maintaining the levels above 30-33 ng/mL help improve the response to bisphosphonates. It is unknown if the response is the same in GIO, but in the clinical practice the levels are maintained at around the same values. In this study we demonstrate that patients with autoimmune diseases, undergoing glucocorticoid therapy, often present suboptimal 25(OH)D levels. Patients with higher body mass index and those receiving higher doses of glucocorticoids are at increased risk of having lower levels of 25(OH)D. In these patients, calcidiol supplementations are more effective than cholecalciferol to reach adequate 25(OH)D levels.

  13. Oral Calcidiol Is More Effective Than Cholecalciferol Supplementation to Reach Adequate 25(OH)D Levels in Patients with Autoimmune Diseases Chronically Treated with Low Doses of Glucocorticoids: A “Real-Life” Study

    PubMed Central

    Ortego-Jurado, Miguel; Callejas-Rubio, José-Luis; Ríos-Fernández, Raquel; González-Moreno, Juan; González Ramírez, Amanda Rocío; González-Gay, Miguel A.; Ortego-Centeno, Norberto

    2015-01-01

    Glucocorticoids (GCs) are the cornerstone of the therapy in many autoimmune and inflammatory diseases. However, it is well known that their use is a double edged sword, as their beneficial effects are associated almost universally with unwanted effects, as, for example glucocorticoid-induced osteoporosis (GIO). Over the last years, several clinical practice guidelines emphasize the need of preventing bone mass loss and reduce the incidence of fractures associated with GC use. Calcium and vitamin D supplementation, as adjunctive therapy, are included in all the practice guidelines. However, no standard vitamin D dose has been established. Several studies with postmenopausal women show that maintaining the levels above 30–33 ng/mL help improve the response to bisphosphonates. It is unknown if the response is the same in GIO, but in the clinical practice the levels are maintained at around the same values. In this study we demonstrate that patients with autoimmune diseases, undergoing glucocorticoid therapy, often present suboptimal 25(OH)D levels. Patients with higher body mass index and those receiving higher doses of glucocorticoids are at increased risk of having lower levels of 25(OH)D. In these patients, calcidiol supplementations are more effective than cholecalciferol to reach adequate 25(OH)D levels. PMID:26124976

  14. Adverse prognostic value of peritumoral vascular invasion: is it abrogated by adequate endocrine adjuvant therapy? Results from two International Breast Cancer Study Group randomized trials of chemoendocrine adjuvant therapy for early breast cancer

    PubMed Central

    Viale, G.; Giobbie-Hurder, A.; Gusterson, B. A.; Maiorano, E.; Mastropasqua, M. G.; Sonzogni, A.; Mallon, E.; Colleoni, M.; Castiglione-Gertsch, M.; Regan, M. M.; Brown, R. W.; Golouh, R.; Crivellari, D.; Karlsson, P.; Öhlschlegel, C.; Gelber, R. D.; Goldhirsch, A.; Coates, A. S.

    2010-01-01

    Background: Peritumoral vascular invasion (PVI) may assist in assigning optimal adjuvant systemic therapy for women with early breast cancer. Patients and methods: Patients participated in two International Breast Cancer Study Group randomized trials testing chemoendocrine adjuvant therapies in premenopausal (trial VIII) or postmenopausal (trial IX) node-negative breast cancer. PVI was assessed by institutional pathologists and/or central review on hematoxylin–eosin-stained slides in 99% of patients (analysis cohort 2754 patients, median follow-up >9 years). Results: PVI, present in 23% of the tumors, was associated with higher grade tumors and larger tumor size (trial IX only). Presence of PVI increased locoregional and distant recurrence and was significantly associated with poorer disease-free survival. The adverse prognostic impact of PVI in trial VIII was limited to premenopausal patients with endocrine-responsive tumors randomized to therapies not containing goserelin, and conversely the beneficial effect of goserelin was limited to patients whose tumors showed PVI. In trial IX, all patients received tamoxifen: the adverse prognostic impact of PVI was limited to patients with receptor-negative tumors regardless of chemotherapy. Conclusion: Adequate endocrine adjuvant therapy appears to abrogate the adverse impact of PVI in node-negative disease, while PVI may identify patients who will benefit particularly from adjuvant therapy. PMID:19633051

  15. Comparability and Reliability Considerations of Adequate Yearly Progress

    ERIC Educational Resources Information Center

    Maier, Kimberly S.; Maiti, Tapabrata; Dass, Sarat C.; Lim, Chae Young

    2012-01-01

    The purpose of this study is to develop an estimate of Adequate Yearly Progress (AYP) that will allow for reliable and valid comparisons among student subgroups, schools, and districts. A shrinkage-type estimator of AYP using the Bayesian framework is described. Using simulated data, the performance of the Bayes estimator will be compared to…

  16. Feasibility study of wireless power transmission systems

    NASA Technical Reports Server (NTRS)

    Robinson, W. J., Jr.

    1968-01-01

    Wireless microwave or laser energy transfers power from a manned earth-orbiting central station to unmanned astronomical substations. More efficient systems are required for the microwave power transmission.

  17. Implications for powering biomarker discovery studies.

    PubMed

    Dibben, Sian M; Holt, Robert J; Davison, Timothy S; Wilson, Claire L; Taylor, Janet; Paul, Ian; McManus, Kieran; Kelly, Paul J; Proutski, Vitali; Harkin, D Paul; Kerr, Peter; Fennell, Dean A; James, Jacqueline A; Kennedy, Richard D

    2012-01-01

    This study examined variations in gene expression between FFPE blocks within tumors of individual patients. Microarray data were used to measure tumor heterogeneity within and between patients and disease states. Data were used to determine the number of samples needed to power biomarker discovery studies. Bias and variation in gene expression were assessed at the intrapatient and interpatient levels and between adenocarcinoma and squamous samples. A mixed-model analysis of variance was fitted to gene expression data and model signatures to assess the statistical significance of observed variations within and between samples and disease states. Sample size analysis, adjusted for sample heterogeneity, was used to determine the number of samples required to support biomarker discovery studies. Variation in gene expression was observed between blocks taken from a single patient. However, this variation was considerably less than differences between histological characteristics. This degree of block-to-block variation still permits biomarker discovery using either macrodissected tumors or whole FFPE sections, provided that intratumor heterogeneity is taken into account. Failure to consider intratumor heterogeneity may result in underpowered biomarker studies that may result in either the generation of longer gene signatures or the inability to identify a viable biomarker. Moreover, the results of this study indicate that a single biopsy sample is suitable for applying a biomarker in non-small-cell lung cancer.

  18. A power calculation guide for fMRI studies.

    PubMed

    Mumford, Jeanette A

    2012-08-01

    In the past, power analyses were not that common for fMRI studies, but recent advances in power calculation techniques and software development are making power analyses much more accessible. As a result, power analyses are more commonly expected in grant applications proposing fMRI studies. Even though the software is somewhat automated, there are important decisions to be made when setting up and carrying out a power analysis. This guide provides tips on carrying out power analyses, including obtaining pilot data, defining a region of interest and other choices to help create reliable power calculations.

  19. Summary and evaluation of the Strategic Defense Initiative Space Power Architecture Study

    NASA Technical Reports Server (NTRS)

    Edenburn, M. (Editor); Smith, J. M. (Editor)

    1989-01-01

    The Space Power Architecture Study (SPAS) identified and evaluated power subsystem options for multimegawatt electric (MMWE) space based weapons and surveillance platforms for the Strategic Defense Initiative (SDI) applications. Steady state requirements of less than 1 MMWE are adequately covered by the SP-100 nuclear space power program and hence were not addressed in the SPAS. Four steady state power systems less than 1 MMWE were investigated with little difference between them on a mass basis. The majority of the burst power systems utilized H(2) from the weapons and were either closed (no effluent), open (effluent release) or steady state with storage (no effluent). Closed systems used nuclear or combustion heat source with thermionic, Rankine, turboalternator, fuel cell and battery conversion devices. Open systems included nuclear or combustion heat sources using turboalternator, magnetohydrodynamic, fuel cell or battery power conversion devices. The steady state systems with storage used the SP-100 or Star-M reactors as energy sources and flywheels, fuel cells or batteries to store energy for burst applications. As with other studies the open systems are by far the lightest, most compact and simplist (most reliable) systems. However, unlike other studies the SPAS studied potential platform operational problems caused by effluents or vibration.

  20. Advanced Space Propulsion Study - Antiproton and Beamed Power Propulsion

    DTIC Science & Technology

    1987-10-01

    a new concept for a very high performance laser-puwhed lightsail that uses near-teri high power laser systems to boost very light payloads to terminal...charged pions have a normal half-life of 26 ns. Because they are moving at 94% of the speed of light , however, their lives are lengthened to 70 ns...Given adequate supplies stashed along the way, a light -weight spacesuit, and enough time, Jack would be able to climb into space instead of having to use

  1. Space station electrical power system availability study

    NASA Technical Reports Server (NTRS)

    Turnquist, Scott R.; Twombly, Mark A.

    1988-01-01

    ARINC Research Corporation performed a preliminary reliability, and maintainability (RAM) anlaysis of the NASA space station Electric Power Station (EPS). The analysis was performed using the ARINC Research developed UNIRAM RAM assessment methodology and software program. The analysis was performed in two phases: EPS modeling and EPS RAM assessment. The EPS was modeled in four parts: the insolar power generation system, the eclipse power generation system, the power management and distribution system (both ring and radial power distribution control unit (PDCU) architectures), and the power distribution to the inner keel PDCUs. The EPS RAM assessment was conducted in five steps: the use of UNIRAM to perform baseline EPS model analyses and to determine the orbital replacement unit (ORU) criticalities; the determination of EPS sensitivity to on-orbit spared of ORUs and the provision of an indication of which ORUs may need to be spared on-orbit; the determination of EPS sensitivity to changes in ORU reliability; the determination of the expected annual number of ORU failures; and the integration of the power generator system model results with the distribution system model results to assess the full EPS. Conclusions were drawn and recommendations were made.

  2. Power system interface and umbilical system study

    NASA Technical Reports Server (NTRS)

    1980-01-01

    System requirements and basic design criteria were defined for berthing or docking a payload to the 25 kW power module which will provide electrical power and attitude control, cooling, data transfer, and communication services to free-flying and Orbiter sortie payloads. The selected umbilical system concept consists of four assemblies and command and display equipment to be installed at the Orbiter payload specialist station: (1) a movable platen assembly which is attached to the power system with EVA operable devices; (2) a slave platen assembly which is attached to the payload with EVA operable devices; (3) a fixed secondary platen permanently installed in the power system; and (4) a fixed secondary platen permanently installed on the payload. Operating modes and sequences are described.

  3. ESPRESSO: taking into account assessment errors on outcome and exposures in power analysis for association studies

    PubMed Central

    Gaye, Amadou; Burton, Thomas W. Y.; Burton, Paul R.

    2015-01-01

    Motivation: Very large studies are required to provide sufficiently big sample sizes for adequately powered association analyses. This can be an expensive undertaking and it is important that an accurate sample size is identified. For more realistic sample size calculation and power analysis, the impact of unmeasured aetiological determinants and the quality of measurement of both outcome and explanatory variables should be taken into account. Conventional methods to analyse power use closed-form solutions that are not flexible enough to cater for all of these elements easily. They often result in a potentially substantial overestimation of the actual power. Results: In this article, we describe the Estimating Sample-size and Power in R by Exploring Simulated Study Outcomes tool that allows assessment errors in power calculation under various biomedical scenarios to be incorporated. We also report a real world analysis where we used this tool to answer an important strategic question for an existing cohort. Availability and implementation: The software is available for online calculation and downloads at http://espresso-research.org. The code is freely available at https://github.com/ESPRESSO-research. Contact: louqman@gmail.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25908791

  4. Results of an electrical power system fault study

    NASA Technical Reports Server (NTRS)

    Dugal-Whitehead, Norma R.; Johnson, Yvette B.

    1992-01-01

    NASA-Marshall conducted a study of electrical power system faults with a view to the development of AI control systems for a spacecraft power system breadboard. The results of this study have been applied to a multichannel high voltage dc spacecraft power system, the Large Autonomous Spacecraft Electrical Power System (LASEPS) breadboard. Some of the faults encountered in testing LASEPS included the shorting of a bus an a falloff in battery cell capacity.

  5. Adequate mathematical modelling of environmental processes

    NASA Astrophysics Data System (ADS)

    Chashechkin, Yu. D.

    2012-04-01

    In environmental observations and laboratory visualization both large scale flow components like currents, jets, vortices, waves and a fine structure are registered (different examples are given). The conventional mathematical modeling both analytical and numerical is directed mostly on description of energetically important flow components. The role of a fine structures is still remains obscured. A variety of existing models makes it difficult to choose the most adequate and to estimate mutual assessment of their degree of correspondence. The goal of the talk is to give scrutiny analysis of kinematics and dynamics of flows. A difference between the concept of "motion" as transformation of vector space into itself with a distance conservation and the concept of "flow" as displacement and rotation of deformable "fluid particles" is underlined. Basic physical quantities of the flow that are density, momentum, energy (entropy) and admixture concentration are selected as physical parameters defined by the fundamental set which includes differential D'Alembert, Navier-Stokes, Fourier's and/or Fick's equations and closing equation of state. All of them are observable and independent. Calculations of continuous Lie groups shown that only the fundamental set is characterized by the ten-parametric Galilelian groups reflecting based principles of mechanics. Presented analysis demonstrates that conventionally used approximations dramatically change the symmetries of the governing equations sets which leads to their incompatibility or even degeneration. The fundamental set is analyzed taking into account condition of compatibility. A high order of the set indicated on complex structure of complete solutions corresponding to physical structure of real flows. Analytical solutions of a number problems including flows induced by diffusion on topography, generation of the periodic internal waves a compact sources in week-dissipative media as well as numerical solutions of the same

  6. Technology Efficiency Study on Nuclear Power and Coal Power in Guangdong Province Based on DEA

    SciTech Connect

    Yinong Li; Dong Wang

    2006-07-01

    Guangdong Province has taken the lead in embarking on nuclear power development to resolve its dire lack of primary resources. With the deepening of the on-going structural reform in the electric power sector in China, the market competition scheme is putting electricity generation enterprises under severe strain. Consequently, it is incumbent upon the nuclear power producers to steadily upgrade management, enhance technical capabilities, reduce cost and improve efficiency. At present, gradual application of such efficiency evaluation methodology has already commenced in some sectors in China including the electric power industry. The purpose of this paper is to use the Data Envelopment Analysis (DEA), which is a cutting-edge approach in the efficiency evaluation field - to study the technological efficiency between nuclear power and coal power in Guangdong Province. The DEA results demonstrate that, as far as Guangdong Province is concerned, the technological efficiency of nuclear power is higher than that of coal power in terms of Technological Efficiency (TE), Pure Technology Efficiency (PTE) and Scale Efficiency (SE). The reason is that nuclear power technology is advanced with a much higher equipment availability factor. Under the same scale, the generation output of nuclear power is far higher than that of equivalent coal power generation. With the environmental protection and sustainable development requirements taken into full account, nuclear power constitutes a clean, safe and highly-efficient energy form which should be extensively harnessed in Guangdong Province to fuel its future continuing economic growth. (authors)

  7. JSC space base/power module studies

    NASA Technical Reports Server (NTRS)

    Craig, J. W.

    1978-01-01

    Users of the Orbiter/Spacelab combination will require both higher electrical power and longer duration than is available with the current baseline system. Present Orbiter/Spacelab mission capability is primarily constrained by the hydrogen and oxygen available to generate power in the Orbiter fuel cells. It is also necessary to assure that considerable attitude or point flexibility is retained to assure efficient operation of the Orbiter radiator cooling system. Beyond these early limitations, it is foreseen that orbital operations will eventually need even greater quantities of the basic space utilities: electrical power; heat rejection; and attitude control. Such operations, forecasted for the mid to late 1980's, will be best accommodated by a module stored in orbit that can furnish these to a docked Orbiter/Spacelab or other vehicles. The Orbital Service Module concept to provide for these services is presented.

  8. Power estimation using simulations for air pollution time-series studies

    PubMed Central

    2012-01-01

    Background Estimation of power to assess associations of interest can be challenging for time-series studies of the acute health effects of air pollution because there are two dimensions of sample size (time-series length and daily outcome counts), and because these studies often use generalized linear models to control for complex patterns of covariation between pollutants and time trends, meteorology and possibly other pollutants. In general, statistical software packages for power estimation rely on simplifying assumptions that may not adequately capture this complexity. Here we examine the impact of various factors affecting power using simulations, with comparison of power estimates obtained from simulations with those obtained using statistical software. Methods Power was estimated for various analyses within a time-series study of air pollution and emergency department visits using simulations for specified scenarios. Mean daily emergency department visit counts, model parameter value estimates and daily values for air pollution and meteorological variables from actual data (8/1/98 to 7/31/99 in Atlanta) were used to generate simulated daily outcome counts with specified temporal associations with air pollutants and randomly generated error based on a Poisson distribution. Power was estimated by conducting analyses of the association between simulated daily outcome counts and air pollution in 2000 data sets for each scenario. Power estimates from simulations and statistical software (G*Power and PASS) were compared. Results In the simulation results, increasing time-series length and average daily outcome counts both increased power to a similar extent. Our results also illustrate the low power that can result from using outcomes with low daily counts or short time series, and the reduction in power that can accompany use of multipollutant models. Power estimates obtained using standard statistical software were very similar to those from the simulations

  9. EPA RE-Powering Mapper Feasibility Studies

    EPA Pesticide Factsheets

    The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated the RE-Powering America's Land Initiative to demonstrate the enormous potential that contaminated lands, landfills, and mine sites provide for developing renewable energy in the United States. As part of the RE-Powering America's Land Initiative, the EPA and the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) evaluated the feasibility of developing renewable energy production on Superfund, brownfields, and former landfill or mining sites. These reports pair EPA's expertise on contaminated sites with the renewable energy expertise of NREL.

  10. Development of PowerMap: a software package for statistical power calculation in neuroimaging studies.

    PubMed

    Joyce, Karen E; Hayasaka, Satoru

    2012-10-01

    Although there are a number of statistical software tools for voxel-based massively univariate analysis of neuroimaging data, such as fMRI (functional MRI), PET (positron emission tomography), and VBM (voxel-based morphometry), very few software tools exist for power and sample size calculation for neuroimaging studies. Unlike typical biomedical studies, outcomes from neuroimaging studies are 3D images of correlated voxels, requiring a correction for massive multiple comparisons. Thus, a specialized power calculation tool is needed for planning neuroimaging studies. To facilitate this process, we developed a software tool specifically designed for neuroimaging data. The software tool, called PowerMap, implements theoretical power calculation algorithms based on non-central random field theory. It can also calculate power for statistical analyses with FDR (false discovery rate) corrections. This GUI (graphical user interface)-based tool enables neuroimaging researchers without advanced knowledge in imaging statistics to calculate power and sample size in the form of 3D images. In this paper, we provide an overview of the statistical framework behind the PowerMap tool. Three worked examples are also provided, a regression analysis, an ANOVA (analysis of variance), and a two-sample T-test, in order to demonstrate the study planning process with PowerMap. We envision that PowerMap will be a great aide for future neuroimaging research.

  11. Small-for-gestational age and large-for-gestational age thresholds to predict infants at risk of adverse delivery and neonatal outcomes: are current charts adequate? An observational study from the Born in Bradford cohort

    PubMed Central

    Norris, T; Johnson, W; Farrar, D; Tuffnell, D; Wright, J; Cameron, N

    2015-01-01

    Objectives Construct an ethnic-specific chart and compare the prediction of adverse outcomes using this chart with the clinically recommended UK-WHO and customised birth weight charts using cut-offs for small-for-gestational age (SGA: birth weight <10th centile) and large-for-gestational age (LGA: birth weight >90th centile). Design Prospective cohort study. Setting Born in Bradford (BiB) study, UK. Participants 3980 White British and 4448 Pakistani infants with complete data for gestational age, birth weight, ethnicity, maternal height, weight and parity. Main outcome measures Prevalence of SGA and LGA, using the three charts and indicators of diagnostic utility (sensitivity, specificity and area under the receiver operating characteristic (AUROC)) of these chart-specific cut-offs to predict delivery and neonatal outcomes and a composite outcome. Results In White British and Pakistani infants, the prevalence of SGA and LGA differed depending on the chart used. Increased risk of SGA was observed when using the UK-WHO and customised charts as opposed to the ethnic-specific chart, while the opposite was apparent when classifying LGA infants. However, the predictive utility of all three charts to identify adverse clinical outcomes was poor, with only the prediction of shoulder dystocia achieving an AUROC>0.62 on all three charts. Conclusions Despite being recommended in national clinical guidelines, the UK-WHO and customised birth weight charts perform poorly at identifying infants at risk of adverse neonatal outcomes. Being small or large may increase the risk of an adverse outcome; however, size alone is not sensitive or specific enough with current detection to be useful. However, a significant amount of missing data for some of the outcomes may have limited the power needed to determine true associations. PMID:25783424

  12. The Power Station Game: A Study.

    ERIC Educational Resources Information Center

    Millar, J. W. L.

    1979-01-01

    Presents a description of the power station game as a simulation exercise topic in physics and society, namely the making of a decision which involves many aspects of technical knowledge. Discusses the results of evaluation of students' attitudes toward the game, and attributes that make simulation an attractive teaching option. (GA)

  13. Navies and Soft Power: Historical Case Studies of Naval Power and the Nonuse of Military Force

    DTIC Science & Technology

    2015-06-01

    Finally, it assesses how these deployments might relate to future Chinese naval development. Historical Background A sharp increase in piracy attacks...42 Navies and Soft Power Historical Case Studies of Naval Power and the Nonuse of Military Force N A V A L W A R C O LLE G E N E W P O R T PA P...Newport, Rhode Island, authenticates Navies and Soft Power: Historical Case Studies of Naval Power and the Nonuse of Military Force, edited by Bruce A

  14. A study of fault injection in multichannel spacecraft power systems

    NASA Technical Reports Server (NTRS)

    Dugal-Whitehead, Norma R.; Johnson, Yvette B.

    1991-01-01

    NASA/Marshall Space Flight Center proposes to implement fault injection into an electrical power system breadboard to study the reactions of the various control elements of this breadboard. Among the elements to be studied are the remote power controllers, the algorithms in the control computers, and the artificially intelligent control programs resident in this breadboard. To this end, a study of electrical power is being performed to yield a list of the most common power system faults. The results of this study are being applied to a multichannel high-voltage DC spacecraft power system called the Large Autonomous Spacecraft Electrical Power System Breadboard. Some of the reactions of the breadboard to some of the faults which have been encountered are presented along with the results of this study.

  15. Results of an electrical power system fault study (CDDF)

    NASA Technical Reports Server (NTRS)

    Dugal-Whitehead, N. R.; Johnson, Y. B.

    1993-01-01

    This report gives the results of an electrical power system fault study which has been conducted over the last 2 and one-half years. First, the results of the literature search into electrical power system faults in space and terrestrial power system applications are reported. A description of the intended implementations of the power system faults into the Large Autonomous Spacecraft Electrical Power System (LASEPS) breadboard is then presented. Then, the actual implementation of the faults into the breadboard is discussed along with a discussion describing the LASEPS breadboard. Finally, the results of the injected faults and breadboard failures are discussed.

  16. Photovoltaic power systems workshop

    NASA Technical Reports Server (NTRS)

    Killian, H. J.; Given, R. W.

    1978-01-01

    Discussions are presented on apparent deficiencies in NASA planning and technology development relating to a standard power module (25-35 kW) and to future photovoltaic power systems in general. Topics of discussion consider the following: (1) adequate studies on power systems; (2) whether a standard power system module should be developed from a standard spacecraft; (3) identification of proper approaches to cost reduction; (4) energy storage avoidance; (5) attitude control; (6) thermal effects of heat rejection on solar array configuration stability; (7) assembly of large power systems in space; and (8) factoring terrestrial photovoltaic work into space power systems for possible payoff.

  17. Power transmission studies for tethered SP-100

    NASA Technical Reports Server (NTRS)

    Bents, David J.

    1988-01-01

    The tether and/or transmission line connecting the SP-100 to Space Station presents some unorthodox challenges in high voltage engineering, power transmission, and distribution. The line, which doubles as a structural element of this unusual spacecraft, will convey HVDC from SP-100 to the platform in low Earth orbit, and environment where the local plasma is sufficient to cause breakdown of exposed conductors at potentials of only a few hundred volts. Its anticipated several years operation, and continuously accumulating exposure to meteoroids and debris, raises an increasing likelihood that mechanical damage, including perforation, will be sustained in service. The present concept employs an array of gas insulated solid wall aluminum coaxial tubes; a conceptual design which showed basic feasibility of the SP-100 powered Space Station. Practical considerations of launch, deployment and assembly have led to investigation of reel deployable, dielectric insulated coaxial cables. To be competitive, the dielectric would have to operate reliably in a radiation environment under electrical stresses exceeding 50 kV/cm. The SP-100 transmission line high voltage interfaces are also considered.

  18. Power transmission studies for tethered SP-100

    NASA Technical Reports Server (NTRS)

    Bents, David J.

    1988-01-01

    The tether and/or transmission line connecting the SP-100 to space station presents some unorthodox challenges in high voltage engineering, power transmission, and distribution. The line, which doubles as a structural element of this unusual spacecraft, will convey HVDC from SP-100 to the platform in low Earth orbit, and environment where the local plasma is sufficient to cause breakdown of exposed conductors at potentials of only a few hundred volts. Its anticipated several years operation, and continuously accumulating exposure to meteoroids and debris, raises an increasing likelihood that mechanical damage, including perforation, will be sustained in service. The present concept employs an array of gas insulated solid wall aluminum coaxial tubes; a conceptual design which showed basic feasibility of the SP-100 powered space station. Practical considerations of launch, deployment and assembly have lead to investigation of reel deployable, dielectric insulated coaxial cables. To be competitive, the dielectric would have to operate reliably in a radiation environment under electrical stresses exceeding 50 kV/cm. The SP-100 transmission line high voltage interfaces are also considered.

  19. Optimal study design with identical power: an application of power equivalence to latent growth curve models.

    PubMed

    von Oertzen, Timo; Brandmaier, Andreas M

    2013-06-01

    Structural equation models have become a broadly applied data-analytic framework. Among them, latent growth curve models have become a standard method in longitudinal research. However, researchers often rely solely on rules of thumb about statistical power in their study designs. The theory of power equivalence provides an analytical answer to the question of how design factors, for example, the number of observed indicators and the number of time points assessed in repeated measures, trade off against each other while holding the power for likelihood-ratio tests on the latent structure constant. In this article, we present applications of power-equivalent transformations on a model with data from a previously published study on cognitive aging, and highlight consequences of participant attrition on power.

  20. Optical study of solar tower power plants

    NASA Astrophysics Data System (ADS)

    Eddhibi, F.; Ben Amara, M.; Balghouthi, M.; Guizani, A.

    2015-04-01

    The central receiver technology for electricity generation consists of concentrating solar radiation coming from the solar tracker field into a central receiver surface located on the top of the tower. The heliostat field is constituted of a big number of reflective mirrors; each heliostat tracks the sun individually and reflects the sunlight to a focal point. Therefore, the heliostat should be positioned with high precision in order to minimize optical losses. In the current work, a mathematical model for the analysis of the optical efficiency of solar tower field power plant is proposed. The impact of the different factors which influence the optical efficiency is analyzed. These parameters are mainly, the shading and blocking losses, the cosine effect, the atmospheric attenuation and the spillage losses. A new method for the calculation of blocking and shadowing efficiency is introduced and validated by open literature.

  1. Wind Power Forecasting Error Frequency Analyses for Operational Power System Studies: Preprint

    SciTech Connect

    Florita, A.; Hodge, B. M.; Milligan, M.

    2012-08-01

    The examination of wind power forecasting errors is crucial for optimal unit commitment and economic dispatch of power systems with significant wind power penetrations. This scheduling process includes both renewable and nonrenewable generators, and the incorporation of wind power forecasts will become increasingly important as wind fleets constitute a larger portion of generation portfolios. This research considers the Western Wind and Solar Integration Study database of wind power forecasts and numerical actualizations. This database comprises more than 30,000 locations spread over the western United States, with a total wind power capacity of 960 GW. Error analyses for individual sites and for specific balancing areas are performed using the database, quantifying the fit to theoretical distributions through goodness-of-fit metrics. Insights into wind-power forecasting error distributions are established for various levels of temporal and spatial resolution, contrasts made among the frequency distribution alternatives, and recommendations put forth for harnessing the results. Empirical data are used to produce more realistic site-level forecasts than previously employed, such that higher resolution operational studies are possible. This research feeds into a larger work of renewable integration through the links wind power forecasting has with various operational issues, such as stochastic unit commitment and flexible reserve level determination.

  2. Study on the statistical characteristics of solar power

    NASA Astrophysics Data System (ADS)

    Liu, Jun

    2017-01-01

    Solar power in China has grown rapidly recently. It exists variation of solar power due to cloudy and dusty, which is not that much of wind. The way to evaluate the statistical characteristics of solar power is important to the analysis of power system planning and operation. In this study, a multi-scale spatial and temporal framework of evaluating indices was established to describe the variation of its own natural features and the interaction between solar and load, grids. Finally, we have a case study on the variation, comparison, penetration, etc.

  3. Are shear force methods adequately reported?

    PubMed

    Holman, Benjamin W B; Fowler, Stephanie M; Hopkins, David L

    2016-09-01

    This study aimed to determine the detail to which shear force (SF) protocols and methods have been reported in the scientific literature between 2009 and 2015. Articles (n=734) published in peer-reviewed animal and food science journals and limited to only those testing the SF of unprocessed and non-fabricated mammal meats were evaluated. It was found that most of these SF articles originated in Europe (35.3%), investigated bovine species (49.0%), measured m. longissimus samples (55.2%), used tenderometers manufactured by Instron (31.2%), and equipped with Warner-Bratzler blades (68.8%). SF samples were also predominantly thawed prior to cooking (37.1%) and cooked sous vide, using a water bath (50.5%). Information pertaining to blade crosshead speed (47.5%), recorded SF resistance (56.7%), muscle fibre orientation when tested (49.2%), sub-section or core dimension (21.8%), end-point temperature (29.3%), and other factors contributing to SF variation were often omitted. This base failure diminishes repeatability and accurate SF interpretation, and must therefore be rectified.

  4. Space-based solar power conversion and delivery systems study

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Even at reduced rates of growth, the demand for electric power is expected to more than triple between now and 1995, and to triple again over the period 1995-2020. Without the development of new power sources and advanced transmission technologies, it may not be possible to supply electric energy at prices that are conductive to generalized economic welfare. Solar power is renewable and its conversion and transmission from space may be advantageous. The goal of this study is to assess the economic merit of space-based photovoltaic systems for power generation and a power relay satellite for power transmission. In this study, satellite solar power generation and transmission systems, as represented by current configurations of the Satellite Solar Station (SSPS) and the Power Relay Satellite (PRS), are compared with current and future terrestrial power generation and transmission systems to determine their technical and economic suitability for meeting power demands in the period of 1990 and beyond while meeting ever-increasing environmental and social constraints.

  5. Steady-state and dynamic models of unified power flow controller (UPFC) for power system studies

    SciTech Connect

    Nabavi-Niaki, A.; Iravani, M.R.

    1996-11-01

    This paper provides comprehensive development procedures and final forms of mathematical models of unified power flow controller (UPFC) for steady-state, transient stability and eigenvalue studies. Based on the developed models, the impacts of control strategy, parameters and location of UPFC on power system operating conditions are discussed. The accuracy of the developed models is verified through comparing the study results with those obtained from detailed time-domain simulation using the Electromagnetic Transients Program (EMTP).

  6. Tokamak power system studies at ANL

    SciTech Connect

    Baker, C.C.; Ehst, D.A.; Brooks, J.N.; Evans, K. Jr.

    1986-06-01

    The following features, in particular, have been examined: (a) large aspect ratio (A approx. = 6), which may ease maintenance; (b) high beta (..beta.. greater than or equal to 0.20) without indentation, which brings the maximum toroidal field down to about 6 to 7 T; (c) low toroidal current (I approx. = 4MA), which reduces the cost of the current drive and equilibrium field system; and (d) steady state operation with current density control via fast and slow wave current drive. The key to high beta operation with low toroidal current lies in utilizing second stability regime equilibria with the required current distributions produced by an appropriate selection of wave driver frequencies and power spectra. The ray tracing and current drive calculation is self-consistent with the actual magnetic fields they produce in the plasma. The impurity control activities in TPSS have emphasized the self-pumping concept as applied to using the entire first wall or ''slot'' limiters. The blanket design effort has emphasized liquid metal and Flibe concepts. The reference concept is a liquid lithium/vanadium, self-cooled configuration. Overall, there exists a number of major design improvements which will substantially improve the attractiveness of tokamak reactors.

  7. Study of a High Voltage Ion Engine Power Supply

    NASA Technical Reports Server (NTRS)

    Stuart, Thomas A.; King, Roger J.; Mayer, Eric

    1996-01-01

    A complete laboratory breadboard version of a ion engine power converter was built and tested. This prototype operated on a line voltage of 80-120 Vdc, and provided output ratings of 1100 V at 1.8 kW, and 250 V at 20 mA. The high-voltage (HV) output voltage rating was revised from the original value of 1350 V at the beginning of the project. The LV output was designed to hold up during a 1-A surge current lasting up to 1 second. The prototype power converter included a internal housekeeping power supply which also operated from the line input. The power consumed in housekeeping was included in the overall energy budget presented for the ion engine converter. HV and LV output voltage setpoints were commanded through potentiometers. The HV converter itself reached its highest power efficiency of slightly over 93% at low line and maximum output. This would dip below 90% at high line. The no-load (rated output voltages, zero load current) power consumption of the entire system was less than 13 W. A careful loss breakdown shows that converter losses are predominately Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) conduction losses and HV rectifier snubbing losses, with the rectifier snubbing losses becoming predominant at high line. This suggests that further improvements in power efficiency could best be obtained by either developing a rectifier that was adequately protected against voltage overshoot with less snubbing, or by developing a pre-regulator to reduced the range of line voltage on the converter. The transient testing showed the converter to be fully protected against load faults, including a direct short-circuit from the HV output to the LV output terminals. Two currents sensors were used: one to directly detect any core ratcheting on the output transformer and re-initiate a soft start, and the other to directly detect a load fault and quickly shut down the converter for load protection. The finished converter has been extensively fault tested

  8. Mars power system concept definition study. Volume 2: Appendices

    NASA Technical Reports Server (NTRS)

    Littman, Franklin D.

    1994-01-01

    This report documents the work performed by Rockwell International's Rocketdyne Division on NASA Contract No. NAS3-25808 (Task Order No. 16) entitled 'Mars Power System Definition Study'. This work was performed for NASA's Lewis Research Center (LeRC). The report is divided into two volumes as follows: Volume 1 - Study Results; and Volume 2 - Appendices. The results of the power system characterization studies, operations studies, and technology evaluations are summarized in Volume 1. The appendices include complete, standalone technology development plans for each candidate power system that was investigated.

  9. Mars power system concept definition study. Volume 2: Appendices

    NASA Astrophysics Data System (ADS)

    Littman, Franklin D.

    1994-12-01

    This report documents the work performed by Rockwell International's Rocketdyne Division on NASA Contract No. NAS3-25808 (Task Order No. 16) entitled 'Mars Power System Definition Study'. This work was performed for NASA's Lewis Research Center (LeRC). The report is divided into two volumes as follows: Volume 1 - Study Results; and Volume 2 - Appendices. The results of the power system characterization studies, operations studies, and technology evaluations are summarized in Volume 1. The appendices include complete, standalone technology development plans for each candidate power system that was investigated.

  10. Total Ownership Cost Reduction Case Study: AEGIS Microwave Power Tubes

    DTIC Science & Technology

    2006-05-31

    SUPPORT FUNCTIONS SPY-1A CFA SPY-1A Ring-Bar TWT SPY-1A Helix TWT SPG-62 CC-TWT SPS-49 Klystron UPX-29 Power Gridded Tube SPG-62 (Mk-99) CC...SPQ-9 (Mk-86) Klystron LN-66 Magnetron All Combat Systems Above 1 GHz Powered by Microwave Power Tubes As can be seen, many...Graduate School of Bus Eugene (J Naval Surface Warfar Approved for public rele t Reduction Case Study: ave Power Tubes ay 2006 by

  11. Designing Intervention Studies: Selected Populations, Range Restrictions, and Statistical Power

    ERIC Educational Resources Information Center

    Miciak, Jeremy; Taylor, W. Pat; Stuebing, Karla K.; Fletcher, Jack M.; Vaughn, Sharon

    2016-01-01

    An appropriate estimate of statistical power is critical for the design of intervention studies. Although the inclusion of a pretest covariate in the test of the primary outcome can increase statistical power, samples selected on the basis of pretest performance may demonstrate range restriction on the selection measure and other correlated…

  12. ERDA's central receiver solar thermal power system studies

    NASA Technical Reports Server (NTRS)

    Lippy, L. J.; Heaton, T. R.

    1977-01-01

    The utilization of solar energy for electrical power production was studied. Efforts underway on the central receiver solar thermal power system are presented. Preliminary designs are included of pilot plant utilizing large numbers of heliostats in a collector field. Safety hazards are also discussed, as well as the most beneficial location of such a plant within the United States.

  13. Study of solar array switching power management technology for space power system

    NASA Technical Reports Server (NTRS)

    Cassinelli, J. E.

    1982-01-01

    This report documents work performed on the Solar Array Switching Power Management Study. Mission characteristics for three missions were defined to the depth necessary to determine their power management requirements. Solar array switching concepts were identified that could safisfy the mission requirements. These switching concepts were compared with a conventional buck regulator system on the basis of cost, weight and volume, reliability, efficiency and thermal control. For the missions reviewed, solar array switching provided significant advantages in all areas of comparison.

  14. Study of solar array switching power management technology for space power system

    NASA Technical Reports Server (NTRS)

    Cassinelli, J. E.

    1982-01-01

    This report documents work performed on the Solar Array Switching Power Management Study. Mission characteristics for three missions were defined to the depth necessary to determine their power management requirements. Solar array switching concepts which could satisfy the mission requirements were identified. The switching concepts were compared with a conventional buck regulator system for cost, weight and volume, reliability, efficiency and thermal control. Solar array switching provided significant advantages in all areas of comparison for the reviewed missions.

  15. A Feasibility Study of Oscillating-Wing Power Generators

    NASA Astrophysics Data System (ADS)

    Lindsey, Keon

    2002-09-01

    Mankind is continually searching for new sources of energy or methods to harness known sources. Recently, renewable and zero-pollution energy supplies are of great interest. Consequently, power generation from a fluttering wing is studied numerically and experimentally. Previous studies have suggested that an oscillating-wing used to extract energy from a fluid flow could deliver power comparable to windmills. Several studies are examined. An oscillating-wing power generator is designed and tested. The experimental results are compared with numerical predictions. Finally, commercial applications of the "environmentally friendly" oscillating-wing generator are investigated.

  16. Theoretical study of pump power distribution on modal instabilities in high power fiber amplifiers

    NASA Astrophysics Data System (ADS)

    Tao, Rumao; Ma, Pengfei; Wang, Xiaolin; Zhou, Pu; Liu, Zejin

    2017-02-01

    Influence of pump power distribution on modal instabilities (MI) is studied numerically, which reveals that the MI threshold is dependent on the pump power distribution in fiber amplifiers and can be increased by optimizing the pump power distribution without any adjustment of other amplifier parameters. It shows that amplifiers with backward or bi-direction pump schemes have a higher threshold than those employing forward pump schemes. For backward pumped amplifiers employing fiber with core/clad diameter being 20/400 µm, the MI threshold yields a 42% increase compared to the forward pumped ones. For bi-direction pumped amplifiers, there exists an optimal power ratio between forward and backward pump power, which results in the highest threshold power. When amplifiers with core/clad diameter being 20/400 µm employ a bi-direction pump scheme at the optimal backward pump power fraction, the threshold can be increased by a factor of approximately 60% with respect to the forward pump configuration. The threshold increment factor reduces as the gain saturation effect weakens. It also shows that the MI threshold can be increased by employing multi-point side pump schemes.

  17. Winter study of power plant effects

    SciTech Connect

    Patrinos, A.A.N.

    1980-10-01

    As a part of DOE's Meteorological Effects of Thermal Energy Releases (METER) program a field study was undertaken at the Bowen Electric Generating Plant (Plant Bowen) in December 1979. The study was a joint endeavor of Battelle Pacific Northwest Laboratories (PNL), Pennsylvania State University (PSU), and Oak Ridge National Laboratory (ORNL) with the main objective of determining the effects of the plant's smokestack effluents on aerosol characteristics and precipitation chemistry. Other objectives included studies of cooling tower temperature and humidity (T/h) plumes and drift drop concentrations. Conducted over a period of three weeks, the study involved an instrumented aircraft, pilot balloons, a tethered balloon system, a dense network of wetfall chemistry collectors and numerous ground- and tower-based meteorological instruments. Rainfall samples collected during the precipitation event of December 13, 1979, revealed some evidence of plume washout. The tethered balloon flights rarely detected the faint presence of the T/h plumes while the airborne measurements program concentrated on the study of SO/sub 2/ to sulfate conversion. A series of plume observations confirmed the suitability of the plant's windset for plume direction determinations.

  18. 25 kW power module evolution study

    NASA Technical Reports Server (NTRS)

    Overall, J. W., Jr.

    1979-01-01

    This paper presents a study of evolutionary growth concepts for the 25 kW power module to augment STS mission support future capabilities. The study aimed to establish user payload requirements, define evolution methods for system initial operational capability, and formulate a development program and conceptual designs. The payload requirements analysis focused on material processing in space, public services, and solar terrestrial observations; evolutionary system concepts were evaluated to derive the power module and system support requirements, and four reference orbits were used to construct the nominal program scenario. The mission accomodations analysis evaluated the capability of the nominal program scenario and associated power module concepts to meet user needs. Finally, the recommended modular design consisting of electric power, attitude control, thermal control, and command and data handling is described, and it is concluded that the 25 kW power module is a logical first step to support the near term NASA sortie and free-flyer mission requirements.

  19. Optimal sample sizes for the design of reliability studies: power consideration.

    PubMed

    Shieh, Gwowen

    2014-09-01

    Intraclass correlation coefficients are used extensively to measure the reliability or degree of resemblance among group members in multilevel research. This study concerns the problem of the necessary sample size to ensure adequate statistical power for hypothesis tests concerning the intraclass correlation coefficient in the one-way random-effects model. In view of the incomplete and problematic numerical results in the literature, the approximate sample size formula constructed from Fisher's transformation is reevaluated and compared with an exact approach across a wide range of model configurations. These comprehensive examinations showed that the Fisher transformation method is appropriate only under limited circumstances, and therefore it is not recommended as a general method in practice. For advance design planning of reliability studies, the exact sample size procedures are fully described and illustrated for various allocation and cost schemes. Corresponding computer programs are also developed to implement the suggested algorithms.

  20. Conceptual study of superconducting urban area power systems

    NASA Astrophysics Data System (ADS)

    Noe, Mathias; Bach, Robert; Prusseit, Werner; Willén, Dag; Gold-acker, Wilfried; Poelchau, Juri; Linke, Christian

    2010-06-01

    Efficient transmission, distribution and usage of electricity are fundamental requirements for providing citizens, societies and economies with essential energy resources. It will be a major future challenge to integrate more sustainable generation resources, to meet growing electricity demand and to renew electricity networks. Research and development on superconducting equipment and components have an important role to play in addressing these challenges. Up to now, most studies on superconducting applications in power systems have been concentrated on the application of specific devices like for example cables and current limiters. In contrast to this, the main focus of our study is to show the consequence of a large scale integration of superconducting power equipment in distribution level urban power systems. Specific objectives are to summarize the state-of-the-art of superconducting power equipment including cooling systems and to compare the superconducting power system with respect to energy and economic efficiency with conventional solutions. Several scenarios were considered starting from the replacement of an existing distribution level sub-grid up to a full superconducting urban area distribution level power system. One major result is that a full superconducting urban area distribution level power system could be cost competitive with existing solutions in the future. In addition to that, superconducting power systems offer higher energy efficiency as well as a number of technical advantages like lower voltage drops and improved stability.

  1. 77 FR 18271 - Terrestrial Environmental Studies for Nuclear Power Stations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-27

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Terrestrial Environmental Studies for Nuclear Power Stations AGENCY: Nuclear Regulatory Commission. ACTION: Regulatory guide; issuance. SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing...

  2. 76 FR 50274 - Terrestrial Environmental Studies for Nuclear Power Stations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-12

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Terrestrial Environmental Studies for Nuclear Power Stations AGENCY: Nuclear Regulatory Commission. ACTION: Draft regulatory guide; request for comment. SUMMARY: The U.S. Nuclear Regulatory Commission...

  3. Space shuttle auxiliary power unit study, phase 2

    NASA Technical Reports Server (NTRS)

    Binsley, R. L.; Krause, A. A.; Maddox, R. D.; Marcy, R. D.; Siegler, R. S.

    1972-01-01

    A study was performed to establish the preliminary design of the space shuttle auxiliary power unit. Details of the analysis, optimizations, and design of the components, subsystems and systems are presented.

  4. Microwave Power Transmission System Studies. Volume 1: Executive Summary

    NASA Technical Reports Server (NTRS)

    Maynard, O. E.; Brown, W. C.; Edwards, A.; Meltz, G.; Haley, J. T.; Howell, J. M.; Nathan, A.

    1975-01-01

    A study of microwave power generation, transmission, reception and control was conducted as a part of a program to demonstrate the feasibility of power transmission from geosynchronous orbit. A summary is presented of results concerning design approaches, estimated costs (ROM), critical technology, associated ground and orbital test programs with emphasis on dc to rf conversion, transmitting antenna, phase control, mechanical systems, flight operations, ground power receiving-rectifying antenna with systems analysis, and evaluation. Recommendations for early further in-depth studies complementing the technology program are included.

  5. 2007 Wholesale Power Rate Case Initial Proposal : Wholesale Power Rate Development Study.

    SciTech Connect

    United States. Bonneville Power Administration.

    2007-11-01

    The Wholesale Power Rate Development Study (WPRDS) calculates BPA proposed rates based on information either developed in the WPRDS or supplied by the other studies that comprise the BPA rate proposal. All of these studies, and accompanying documentation, provide the details of computations and assumptions. In general, information about loads and resources is provided by the Load Resource Study (LRS), WP-07-E-BPA-01, and the LRS Documentation, WP-07-E-BPA-01A. Revenue requirements information, as well as the Planned Net Revenues for Risk (PNNR), is provided in the Revenue Requirement Study, WP-07-E-BPA-02, and its accompanying Revenue Requirement Study Documentation, WP-07-E-BPA-02A and WP-07-E-BPA-02B. The Market Price Forecast Study (MPFS), WP-07-E-BPA-03, and the MPFS Documentation, WP-07-E-BPA-03A, provide the WPRDS with information regarding seasonal and diurnal differentiation of energy rates, as well information regarding monthly market prices for Demand Rates. In addition, this study provides information for the pricing of unbundled power products. The Risk Analysis Study, WP-07-E-BPA-04, and the Risk Analysis Study Documentation, WP-07-E-BPA-04A, provide short-term balancing purchases as well as secondary energy sales and revenue. The Section 7(b)(2) Rate Test Study, WP-07-E-BPA-06, and the Section 7(b)(2) Rate Test Study Documentation, WP-07-E-BPA-06A, implement Section 7(b)(2) of the Northwest Power Act to ensure that BPA preference customers firm power rates applied to their general requirements are no higher than rates calculated using specific assumptions in the Northwest Power Act.

  6. On power and sample size calculation in ethnic sensitivity studies.

    PubMed

    Zhang, Wei; Sethuraman, Venkat

    2011-01-01

    In ethnic sensitivity studies, it is of interest to know whether the same dose has the same effect over populations in different regions. Glasbrenner and Rosenkranz (2006) proposed a criterion for ethnic sensitivity studies in the context of different dose-exposure models. Their method is liberal in the sense that their sample size will not achieve the target power. We will show that the power function can be easily calculated by numeric integration, and the sample size can be determined by bisection.

  7. Prostate cancer between prognosis and adequate/proper therapy

    PubMed Central

    Grozescu, T; Popa, F

    2017-01-01

    Knowing the indolent, non-invasive nature of most types of prostate cancer, as well as the simple fact that the disease seems more likely to be associated with age rather than with other factors (50% of men at the age of 50 and 80% at the age of 80 have it [1], with or without presenting any symptom), the big challenge of this clinical entity was to determine severity indicators (so far insufficient) to guide the physician towards an adequate attitude in the clinical setting. The risk of over-diagnosing and over-treating many prostate cancer cases (indicated by all the major European and American studies) is real and poses many question marks. The present paper was meant to deliver new research data and to reset the clinical approach in prostate cancer cases. PMID:28255369

  8. The cerebellopontine angle: does the translabyrinthine approach give adequate access?

    PubMed

    Fagan, P A; Sheehy, J P; Chang, P; Doust, B D; Coakley, D; Atlas, M D

    1998-05-01

    A long-standing but unfounded criticism of the translabyrinthine approach is the misperception that this approach does not give adequate access to the cerebellopontine angle. Because of what is perceived as limited visualization and operating space within the cerebellopontine angle, some surgeons still believe that the translabyrinthine approach is inappropriate for large acoustic tumors. In this study, the surgical access to the cerebellopontine angle by virtue of the translabyrinthine approach is measured and analyzed. The parameters are compared with those measured for the retrosigmoid approach. This series objectively confirms that the translabyrinthine approach offers the neurotologic surgeon a shorter operative depth to the tumor, via a similar-sized craniotomy. This permits superior visualization by virtue of a wider angle of surgical access. Such access is achieved with the merit of minimal cerebellar retraction.

  9. Satellite power system (SPS) magnetron tube assessment study

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Taks performed to extend the data base and to define a technology development program for the magnetron directional amplifier for the SPS are reviewed. These include: (1) demonstrating the tracking of phase and amplitude of the microwave output to phase and amplitude references; (2) expanding the range of power over which the directional amplifier will operate; (3)recognizing the importance of amplitude control in overall system design and in simplifying power conditioning; (4) developing a preliminary design for the overall architecture of the power module; (5) demonstrating magnetron starting using the amplitude control system; (6) mathematically modelling and performing a computerized study of the pyrolytic graphite radiating fin; (7) defining the mass of the magnetic circuit for the SPS tube; (8) noise measurement; (9) achieving harmonic suppression by notch reflection filters; (10) estimating the mass of the transmitting antenna; (11) developing a magnetron package with power generation, phase control, and power condition functions; and (12) projecting magnetron package characteristics.

  10. Nuclear Power Options Viability Study. Volume 3. Nuclear discipline topics

    SciTech Connect

    Trauger, D B; White, J D; Bowers, H I; Braid, R B; Cantor, R A; Daniels, L; Davis, R M; Delene, J G; Gat, U; Hood, T C

    1986-09-01

    Innovative reactor concepts are described and evaluated in accordance with criteria established in the study. The reactors to be studied were chosen on the basis of three ground rules: (1) the potential for commercialization between 2000-2010, (2) economic competiveness with coal-fired plants, and (3) the degree of passive safety in the design. The concepts, classified by coolants, were light water reactors, liquid metal reactors, and high temperature reactors, and most were of modular design. All the concepts appear to be potentially viable in the time frame selected, but the information available is not adequate for a definitive evaluation of their economic competitiveness. This volume primarily reports in greater detail on several topics from the study. These are: Construction, Economics, Regulation, Safety and Economic Risk, Nuclear Waste Transportation and Disposal, and Market Acceptance. Although treated generically, the topics are presented in the context of the reactor concepts of the study.

  11. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Adequate file search. 716.25 Section 716.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of...

  12. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Adequate file search. 716.25 Section 716.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of...

  13. "Something Adequate"? In Memoriam Seamus Heaney, Sister Quinlan, Nirbhaya

    ERIC Educational Resources Information Center

    Parker, Jan

    2014-01-01

    Seamus Heaney talked of poetry's responsibility to represent the "bloody miracle", the "terrible beauty" of atrocity; to create "something adequate". This article asks, what is adequate to the burning and eating of a nun and the murderous gang rape and evisceration of a medical student? It considers Njabulo Ndebele's…

  14. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Adequate file search. 716.25 Section... ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of a person's responsibility to search records is limited to records in the location(s) where the...

  15. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 2 2013-07-01 2013-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  16. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 2 2014-07-01 2014-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  17. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  18. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  19. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 2 2012-07-01 2012-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  20. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  1. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  2. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  3. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  4. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  5. 21 CFR 201.5 - Drugs; adequate directions for use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Drugs; adequate directions for use. 201.5 Section 201.5 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL LABELING General Labeling Provisions § 201.5 Drugs; adequate directions for use....

  6. Solar power satellite offshore rectenna study

    NASA Astrophysics Data System (ADS)

    1980-11-01

    It was found that an offshore rectenna is feasible and cost competitive with land rectennas but that the type of rectenna which is suitable for offshore use is quite different from that specified in the present reference system. The result is a nonground plane design which minimizes the weight and greatly reduces the number of costly support towers. This preferred design is an antenna array consisting of individually encapsulated dipoles with reflectors supported on feed wires. Such a 5 GW rectenna could be built at a 50 m water depth site to withstand hurricane and icing conditions for a one time cost of 5.7 billion dollars. Subsequent units would be about 1/3 less expensive. The east coast site chosen for this study represents an extreme case of severe environmental conditions. More benign and more shallow water sites would result in lower costs. Secondary uses such as mariculture appear practical with only minor impact on the rectenna design. The potential advantages of an offshore rectenna, such as no land requirements, removal of microwave radiation from populated areas and minimal impact on the local geopolitics argue strongly that further investigation of the offshore rectenna should be vigorously pursued.

  7. Solar power satellite offshore rectenna study

    NASA Technical Reports Server (NTRS)

    1980-01-01

    It was found that an offshore rectenna is feasible and cost competitive with land rectennas but that the type of rectenna which is suitable for offshore use is quite different from that specified in the present reference system. The result is a nonground plane design which minimizes the weight and greatly reduces the number of costly support towers. This preferred design is an antenna array consisting of individually encapsulated dipoles with reflectors supported on feed wires. Such a 5 GW rectenna could be built at a 50 m water depth site to withstand hurricane and icing conditions for a one time cost of 5.7 billion dollars. Subsequent units would be about 1/3 less expensive. The east coast site chosen for this study represents an extreme case of severe environmental conditions. More benign and more shallow water sites would result in lower costs. Secondary uses such as mariculture appear practical with only minor impact on the rectenna design. The potential advantages of an offshore rectenna, such as no land requirements, removal of microwave radiation from populated areas and minimal impact on the local geopolitics argue strongly that further investigation of the offshore rectenna should be vigorously pursued.

  8. Space Power Free-Piston Stirling Engine Scaling Study

    NASA Technical Reports Server (NTRS)

    Jones, D.

    1989-01-01

    The design feasibility study is documented of a single cylinder, free piston Stirling engine/linear alternator (FPSE/LA) power module generating 150 kW-electric (kW sub e), and the determination of the module's maximum feasible power level. The power module configuration was specified to be a single cylinder (single piston, single displacer) FPSE/LA, with tuning capacitors if required. The design requirements were as follows: (1) Maximum electrical power output; (2) Power module thermal efficiency equal to or greater than 20 percent at a specific mass of 5 to 8 kg/kW(sub e); (3) Heater wall temperature/cooler wall temperature = 1050 K/525 K; (4) Sodium heat-pipe heat transport system, pumped loop NaK (sodium-potassium eutectic mixture) rejection system; (5) Maximum power module vibration amplitude = 0.0038 cm; and (6) Design life = 7 years (60,000 hr). The results show that a single cylinder FPSE/LA is capable of meeting program goals and has attractive scaling attributes over the power range from 25 to 150 kW(sub e). Scaling beyond the 150 kW(sub e) power level, the power module efficiency falls and the power module specific mass reaches 10 kg/kW(sub e) at a power output of 500 kW(sub e). A discussion of scaling rules for the engine, alternator, and heat transport systems is presented, along with a detailed description of the conceptual design of a 150 kW(sub e) power module that meets the requirements. Included is a discussion of the design of a dynamic balance system. A parametric study of power module performance conducted over the power output range of 25 to 150 kW(sub e) for temperature ratios of 1.7, 2.0, 2.5, and 3.0 is presented and discussed. The results show that as the temperature ratio decreases, the efficiency falls and specific mass increases. At a temperature ratio of 1.7, the 150 kW(sub e) power module cannot satisfy both efficiency and specific mass goals. As the power level increases from 25 to 150 kW(sub e) at a fixed temperature ratio, power

  9. High Temperature Boost (HTB) Power Processing Unit (PPU) Formulation Study

    NASA Technical Reports Server (NTRS)

    Chen, Yuan; Bradley, Arthur T.; Iannello, Christopher J.; Carr, Gregory A.; Mohammad, Mojarradi M.; Hunter, Don J.; DelCastillo, Linda; Stell, Christopher B.

    2013-01-01

    This technical memorandum is to summarize the Formulation Study conducted during fiscal year 2012 on the High Temperature Boost (HTB) Power Processing Unit (PPU). The effort is authorized and supported by the Game Changing Technology Division, NASA Office of the Chief Technologist. NASA center participation during the formulation includes LaRC, KSC and JPL. The Formulation Study continues into fiscal year 2013. The formulation study has focused on the power processing unit. The team has proposed a modular, power scalable, and new technology enabled High Temperature Boost (HTB) PPU, which has 5-10X improvement in PPU specific power/mass and over 30% in-space solar electric system mass saving.

  10. AMERICAN ELECTRIC POWER'S CONESVILLE POWER PLANT UNIT NO.5 CO2 CAPTURE RETROFIT STUDY

    SciTech Connect

    Carl R. Bozzuto; Nsakala ya Nsakala; Gregory N. Liljedahl; Mark Palkes; John L. Marion

    2001-06-30

    ALSTOM Power Inc.'s Power Plant Laboratories (ALSTOM) has teamed with American Electric Power (AEP), ABB Lummus Global Inc. (ABB), the US Department of Energy National Energy Technology Laboratory (DOE NETL), and the Ohio Coal Development Office (OCDO) to conduct a comprehensive study evaluating the technical feasibility and economics of alternate CO{sub 2} capture and sequestration technologies applied to an existing US coal-fired electric generation power plant. The motivation for this study was to provide input to potential US electric utility actions concerning GHG emissions reduction. If the US decides to reduce CO{sub 2} emissions, action would need to be taken to address existing power plants. Although fuel switching from coal to natural gas may be one scenario, it will not necessarily be a sufficient measure and some form of CO{sub 2} capture for use or disposal may also be required. The output of this CO{sub 2} capture study will enhance the public's understanding of control options and influence decisions and actions by government, regulators, and power plant owners in considering the costs of reducing greenhouse gas CO{sub 2} emissions. The total work breakdown structure is encompassed within three major reports, namely: (1) Literature Survey, (2) AEP's Conesville Unit No.5 Retrofit Study, and (3) Bench-Scale Testing and CFD Evaluation. The report on the literature survey results was issued earlier by Bozzuto, et al. (2000). Reports entitled ''AEP's Conesville Unit No.5 Retrofit Study'' and ''Bench-Scale Testing and CFD Evaluation'' are provided as companion volumes, denoted Volumes I and II, respectively, of the final report. The work performed, results obtained, and conclusions and recommendations derived therefrom are summarized.

  11. A Study on a Hybrid Approach for Diagnosing Faults in Nuclear Power Plant

    SciTech Connect

    Yang, M.; Zhang, Z.J.; Peng, M.J.; Yan, S.Y.; Wang, H.; Ouyang, J.

    2006-07-01

    Proper and rapid identification of malfunctions is of premier importance for the safe operation of Nuclear Power Plants (NPP). Many monitoring or/and diagnosis methodologies based on artificial and computational intelligence have been proposed to aid operator to understand system problems, perform trouble-shooting action and reduce human error under serious pressure. However, because no single method is adequate to handle all requirements for diagnostic system, hybrid approaches where different methods work in conjunction to solve parts of the problem interest researchers greatly. In this study, Multilevel Flow Models (MFM) and Artificial Neural Network (ANN) are proposed and employed to develop a fault diagnosis system with the intention of improving the success rate of recognition on the one hand, and improving the understandability of diagnostic process and results on the other hand. Several simulation cases were conducted for evaluating the performance of the proposed diagnosis system. The simulation results validated the effectiveness of the proposed hybrid approach. (authors)

  12. Control-structure interaction study for the Space Station solar dynamic power module

    NASA Technical Reports Server (NTRS)

    Cheng, J.; Ianculescu, G.; Ly, J.; Kim, M.

    1991-01-01

    The authors investigate the feasibility of using a conventional PID (proportional plus integral plus derivative) controller design to perform the pointing and tracking functions for the Space Station Freedom solar dynamic power module. Using this simple controller design, the control/structure interaction effects were also studied without assuming frequency bandwidth separation. From the results, the feasibility of a simple solar dynamic control solution with a reduced-order model, which satisfies the basic system pointing and stability requirements, is suggested. However, the conventional control design approach is shown to be very much influenced by the order of reduction of the plant model, i.e., the number of the retained elastic modes from the full-order model. This suggests that, for complex large space structures, such as the Space Station Freedom solar dynamic, the conventional control system design methods may not be adequate.

  13. Power System Trade Studies for the Lunar Surface Access Module

    NASA Technical Reports Server (NTRS)

    Kohout, Lisa, L.

    2008-01-01

    A Lunar Lander Preparatory Study (LLPS) was undertaken for NASA's Lunar Lander Pre-Project in 2006 to explore a wide breadth of conceptual lunar lander designs. Civil servant teams from nearly every NASA center responded with dozens of innovative designs that addressed one or more specific lander technical challenges. Although none of the conceptual lander designs sought to solve every technical design issue, each added significantly to the technical database available to the Lunar Lander Project Office as it began operations in 2007. As part of the LLPS, a first order analysis was performed to identify candidate power systems for the ascent and descent stages of the Lunar Surface Access Module (LSAM). A power profile by mission phase was established based on LSAM subsystem power requirements. Using this power profile, battery and fuel cell systems were modeled to determine overall mass and volume. Fuel cell systems were chosen for both the descent and ascent stages due to their low mass. While fuel cells looked promising based on these initial results, several areas have been identified for further investigation in subsequent studies, including the identification and incorporation of peak power requirements into the analysis, refinement of the fuel cell models to improve fidelity and incorporate ongoing technology developments, and broadening the study to include solar power.

  14. Multiple frequency bioimpedance is an adequate tool to assess total and regional fat mass in HIV-positive patients but not to diagnose HIV-associated lipoatrophy: a pilot study

    PubMed Central

    Pérez-Matute, Patricia; Pérez-Martínez, Laura; Blanco, José R; Ibarra, Valvanera; Metola, Luis; Sanz, Mercedes; Hernando, Luis; Martínez, Sagrario; Ramírez, Arsenio; Ramalle-Gomara, Enrique; Oteo, José A

    2013-01-01

    Introduction HIV-associated lipodystrophy syndrome causes systemic metabolic alterations and psychological distress that worsen the quality of life of these patients. An early detection should be considered to efficiently treat it. Objective criteria or reference indices are needed for an early diagnosis. Bioelectrical Impedance Analysis (BIA) is an operator-independent, repeatable and non-invasive method of body composition evaluation that is less expensive than dual-energy X-ray absorptiometry (DXA) and/or CT scans. The aims of this pilot study were to validate the data obtained by BIA to measure fat mass in HIV-positive patients with/without lipoatrophy and to determine if BIA correctly diagnoses lipoatrophy in HIV-positive patients. Methods Thirty-nine participants were included in this preliminary study. Fourteen were HIV-negative (eight men) whereas 25 were HIV-positive patients (17 men). Eleven of the HIV-positive patients were classified as lipoatrophic according to subjective evaluation by the physicians. Total and regional body composition was measured in basal conditions by DXA and by BIA. To obtain abdominal CT scan fat values, transverse slices with 6-mm thickness were acquired at the L4-L5 intervertebral space. Results BIA measurements of total and regional body fat were significantly correlated with those obtained by DXA (p < 0.05 to <0.01) in HIV-positive patients. However, agreement between methods was poor as not very high ICC (intraclass correlation coefficient) values were observed. BIA and DXA showed higher ICC values in lipoatrophic patients. The visceral index obtained by BIA was correlated with total and visceral fat in L4 measured by CT scan (r = 0.607 and r = 0.617, respectively, p < 0.01) in HIV-positive patients. The Fat Mass Ratio (FMR) calculated by BIA did not correlate or agree with DXA values. Conclusions Multi-frequency BIA could be an effective method to evaluate the evolution of total and regional fat composition in HIV

  15. An Ecological Perspective of Power in Transformational Learning: A Case Study of Ethical Vegans.

    ERIC Educational Resources Information Center

    McDonald, Barbara; Cervero, Ronald M.; Courtenay, Bradley C.

    1999-01-01

    In-depth interviews with 12 ethical vegans revealed the process of becoming vegetarian. Transformative learning proved to be a journey rather than a one-time decision. Mezirow's transformative theory does not adequately account for the power relations central to this process. Therefore, transformative learning should be viewed more holistically.…

  16. Experimental Study on the Unified Power Flow Controller

    NASA Astrophysics Data System (ADS)

    Matsuki, Junya; Hayashi, Yasuhiro; Kitajima, Shunsuke; Takahashi, Masahiro; Murata, Kenji

    This paper presents the results of experimental study on the performance of a Unified Power Flow Controller (UPFC), one of the FACTS (Flexible AC Transmission Systems) controllers. A laboratory-scale UPFC was manufactured and installed on a laboratory electric power system to investigate its multifunctional capabilities as a power flow controller. The UPFC consists of two 4.5kVA, 200V back-to-back voltage-sourced converters, labeled “Converter 1" and “Converter 2", operated from a common DC link provided by a DC storage capacitor of 380V. It can provide independent control of both the real and reactive power flow in the line. Tests were performed to examine the capabilities of UPFC, under one-machine connected to an infinite-bus system. Steady-state responses under various kinds of operating conditions were measured and analyzed.

  17. A study of Schwarz converters for nuclear powered spacecraft

    NASA Technical Reports Server (NTRS)

    Stuart, Thomas A.; Schwarze, Gene E.

    1987-01-01

    High power space systems which use low dc voltage, high current sources such as thermoelectric generators, will most likely require high voltage conversion for transmission purposes. This study considers the use of the Schwarz resonant converter for use as the basic building block to accomplish this low-to-high voltage conversion for either a dc or an ac spacecraft bus. The Schwarz converter has the important assets of both inherent fault tolerance and resonant operation; parallel operation in modular form is possible. A regulated dc spacecraft bus requires only a single stage converter while a constant frequency ac bus requires a cascaded Schwarz converter configuration. If the power system requires constant output power from the dc generator, then a second converter is required to route unneeded power to a ballast load.

  18. Region 9: Arizona Adequate Letter (10/14/2003)

    EPA Pesticide Factsheets

    This is a letter from Jack P. Broadben,. Director, to Nancy Wrona and Dennis Smith informing them that Maricopa County's motor vehicle emissions budgets in the 2003 MAGCO Maintenance Plan are adequate for transportation conformity purposes.

  19. Region 6: Texas Adequate Letter (4/16/2010)

    EPA Pesticide Factsheets

    This letter from EPA to Texas Commission on Environmental Quality determined 2021 motor vehicle emission budgets for nitrogen oxides (NOx) and volatile organic compounds (VOCs) for Beaumont/Port Arthur area adequate for transportation conformity purposes

  20. Region 2: New Jersey Adequate Letter (5/23/2002)

    EPA Pesticide Factsheets

    This April 22, 2002 letter from EPA to the New Jersey Department of Environmental Protection determined 2007 and 2014 Carbon Monoxide (CO) Mobile Source Emissions Budgets adequate for transportation conformity purposes and will be announced in the Federal

  1. Region 8: Colorado Adequate Letter (10/29/2001)

    EPA Pesticide Factsheets

    This letter from EPA to Colorado Department of Public Health and Environment determined Denvers' particulate matter (PM10) maintenance plan for Motor Vehicle Emissions Budgets adequate for transportation conformity purposes.

  2. Region 1: New Hampshire Adequate Letter (8/12/2008)

    EPA Pesticide Factsheets

    This July 9, 2008 letter from EPA to the New Hampshire Department of Environmental Services, determined the 2009 Motor Vehicle Emissions Budgets (MVEBs) are adequate for transportation conformity purposes and will be announced in the Federal Register (FR).

  3. Region 8: Colorado Adequate Letter (1/20/2004)

    EPA Pesticide Factsheets

    This letter from EPA to Colorado Department of Public Health and Environment determined Greeleys' Carbon Monoxide (CO) maintenance plan for Motor Vehicle Emissions Budgets adequate for transportation conformity purposes and will be announced in the FR.

  4. Region 8: Utah Adequate Letter (6/10/2005)

    EPA Pesticide Factsheets

    This letter from EPA to Utah Department of Environmental Quality determined Salt Lake Citys' and Ogdens' Carbon Monoxide (CO) maintenance plan for Motor Vehicle Emissions Budgets adequate for transportation conformity purposes.

  5. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must...

  6. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must...

  7. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must...

  8. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must...

  9. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must...

  10. Region 6: New Mexico Adequate Letter (8/21/2003)

    EPA Pesticide Factsheets

    This is a letter from Carl Edlund, Director, to Alfredo Santistevan regarding MVEB's contained in the latest revision to the Albuquerque Carbon Monoxide State Implementation Plan (SIP) are adequate for transportation conformity purposes.

  11. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... contained in a system of records are adequately trained to protect the security and privacy of such records..., by degaussing or by overwriting with the appropriate security software, in accordance...

  12. 4 CFR 200.14 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... require access to and use of records contained in a system of records are adequately trained to protect... with the appropriate security software, in accordance with regulations of the Archivist of the...

  13. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... contained in a system of records are adequately trained to protect the security and privacy of such records..., by degaussing or by overwriting with the appropriate security software, in accordance...

  14. 4 CFR 200.14 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... require access to and use of records contained in a system of records are adequately trained to protect... with the appropriate security software, in accordance with regulations of the Archivist of the...

  15. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... contained in a system of records are adequately trained to protect the security and privacy of such records..., by degaussing or by overwriting with the appropriate security software, in accordance...

  16. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... contained in a system of records are adequately trained to protect the security and privacy of such records..., by degaussing or by overwriting with the appropriate security software, in accordance...

  17. 4 CFR 200.14 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... require access to and use of records contained in a system of records are adequately trained to protect... with the appropriate security software, in accordance with regulations of the Archivist of the...

  18. Region 9: Nevada Adequate Letter (3/30/2006)

    EPA Pesticide Factsheets

    This is a letter from Deborah Jordan, Director, to Leo M. Drozdoff regarding Nevada's motor vehicle emissions budgets in the 2005 Truckee Meadows CO Redesignation Request and Maintenance Plan are adequate for transportation conformity decisions.

  19. Communication Studies and the Extended Power Station Game.

    ERIC Educational Resources Information Center

    Marshall, Stewart

    1981-01-01

    An engineering case study is used as the focal point of a communications course. Communications theory and practical exercises are structured around the case study described, an adaptation and extension of the power station game developed in the early 1970s. Includes outline of and sample student activities. (JN)

  20. Study of hybrid power system potential to power agricultural water pump in mountain area

    NASA Astrophysics Data System (ADS)

    Syuhada, Ahmad; Mubarak, Amir Zaki; Maulana, M. Ilham

    2016-03-01

    As industry and Indonesian economy grow fast, there are a lot of agricultural land has changed into housing and industrial land. This causes the agricultural land moves to mountain area. In mountainous agricultural area, farmers use the water resources of small rivers in the groove of the mountain to irrigate the farmland. Farmers use their power to lift up water from the river to their land which causes inefectivity in the work of the farmers. Farmers who have capital utilize pump to raise water to their land. The only way to use pump in mountain area is by using fuel energy as there is no electricity, and the fuel price in mountain area is very expensive. Based on those reasons it is wise to consider the exploration of renewable energy available in the area such as solar energy, wind energy and hybrid energy. This study analyses the potential of the application of hybrid power plant, which is the combination of solar and wind energy, to power agricultural pump. In this research, the data of wind speed and solar radiation are collected from the measurement of BMKG SMPK Plus Sare. Related to the solar energy, the photovoltaic output power calculation is 193 W with duration of irradiation of 5 hours/day. While for the wind energy, the output power of the wind turbine is 459.84 W with blade diameter of 3 m and blow duration of 7 hours/day. The power of the pump is 558 W with 8 hours of usage, and the water capacity is 2.520 liters/hour for farmland with the area of 15 ha. Based on the analysis result, the designed system will generate electricity of 3.210 kW/year with initial investment of US 14,938.

  1. Lake Erie water level study. Appendix E. Power. Final report

    SciTech Connect

    Not Available

    1981-07-01

    This appendix presents the results of the studies on the effects of limited regulation of Lake Erie on hydroelectric power generation. These studies were undertaken by the International Lake Erie Regulation Study Board. The Board was established by the International Joint Commission in 1977 to conduct the study as a result of the reference from the Governments of Canada and the United States. The purpose of the studies was to determine the economic effects of changes in levels and flows as a result of limited regulation of Lake Erie. This appendix contains the study results of the effect on the generation of hydroelectric power on the connecting channels of the Great Lakes and on the St. Lawrence River. The methodologies used in evaluating the effects of the various regulation plans indicate the benefits or losses to hydroelectric power generation in terms of energy and capacity resulting from changes in levels and flows. The methods used in the evaluation were those used in current economic studies by the power entities involved.

  2. Supply of geothermal power from hydrothermal sources: A study of the cost of power in 20 and 40 years

    NASA Astrophysics Data System (ADS)

    Petty, Susan; Livesay, B. J.; Long, W. P.; Geyer, John

    1992-11-01

    This study develops estimates for the amount of hydrothermal geothermal power that could be on line in 20 and 40 years. This study was intended to represent a 'snapshot' in 20 and 40 years of the hydrothermal energy available for electric power production should a market exist for this power. This does not represent the total or maximum amount of hydrothermal power, but is instead an attempt to estimate the rate at which power could be on line constrained by the exploration, development and support infrastructure available to the geothermal industry, but not constrained by the potential market for power.

  3. Study of Thermal Control Systems for orbiting power systems

    NASA Astrophysics Data System (ADS)

    Howell, H. R.

    1981-02-01

    Thermal control system designs were evaluated for the 25 kW power system. Factors considered include long operating life, high reliability, and meteoroid hazards to the space radiator. Based on a cost advantage, the bumpered pumped fluid radiator is recommended for the initial 25 kW power system and intermediate versions up to 50 kW. For advanced power systems with heat rejection rates above 50 kW the lower weight of the advanced heat pipe radiator offsets the higher cost and this design is recommended. The power system payloads heat rejection allocations studies show that a centralized heat rejection system is the most weight and cost effective approach. The thermal interface between the power system and the payloads was addressed and a concept for a contact heat exchanger that eliminates fluid transfer between the power system and the payloads was developed. Finally, a preliminary design of the thermal control system, with emphasis on the radiator and radiator deployment mechanism, is presented.

  4. Study of Thermal Control Systems for orbiting power systems

    NASA Technical Reports Server (NTRS)

    Howell, H. R.

    1981-01-01

    Thermal control system designs were evaluated for the 25 kW power system. Factors considered include long operating life, high reliability, and meteoroid hazards to the space radiator. Based on a cost advantage, the bumpered pumped fluid radiator is recommended for the initial 25 kW power system and intermediate versions up to 50 kW. For advanced power systems with heat rejection rates above 50 kW the lower weight of the advanced heat pipe radiator offsets the higher cost and this design is recommended. The power system payloads heat rejection allocations studies show that a centralized heat rejection system is the most weight and cost effective approach. The thermal interface between the power system and the payloads was addressed and a concept for a contact heat exchanger that eliminates fluid transfer between the power system and the payloads was developed. Finally, a preliminary design of the thermal control system, with emphasis on the radiator and radiator deployment mechanism, is presented.

  5. Solar pond power plant feasibility study for Davis, California

    NASA Technical Reports Server (NTRS)

    Wu, Y. C.; Singer, M. J.; Marsh, H. E.; Harris, J.; Walton, A. L.

    1982-01-01

    The feasibility of constructing a solar pond power plant at Davis, California was studied. Site visits, weather data compilation, soil and water analyses, conceptual system design and analyses, a material and equipment market survey, conceptual site layout, and a preliminary cost estimate were studied. It was concluded that a solar pond power plant is technically feasible, but economically unattractive. The relatively small scale of the proposed plant and the high cost of importing salt resulted in a disproportionately high capital investment with respect to the annual energy production capacity of the plant. Cycle optimization and increased plant size would increase the economical attractiveness of the proposed concept.

  6. Power considerations for the application of detrended fluctuation analysis in gait variability studies

    PubMed Central

    Kuznetsov, Nikita A.; Rhea, Christopher K.

    2017-01-01

    The assessment of gait variability using stochastic signal processing techniques such as detrended fluctuation analysis (DFA) has been shown to be a sensitive tool for evaluation of gait alterations due to aging and neuromuscular disease. However, previous studies have suggested that the application of DFA requires relatively long recordings (600 strides), which is difficult when working with clinical populations or older adults. In this paper we propose a model for predicting DFA variance in experimental data and conduct a Monte Carlo simulation to estimate the sample size and number of trials required to detect a change in DFA scaling exponent. We illustrate the model in a simulation to detect a difference of 0.1 (medium effect) between two groups of subjects when using short gait time series (100 to 200 strides) in the context of between- and within-subject designs. We assumed that the variance of DFA scaling exponent arises due to individual differences, time series length, and experimental error. Results showed that sample sizes required to achieve acceptable power of 80% are practically feasible, especially when using within-subject designs. For example, to detect a group difference in the DFA scaling exponent of 0.1, it would require either 25 subjects and 2 trials per subject or 12 subjects and 4 trials per subject using a within-subject design. We then compared plausibility of such power predictions to the empirically observed power from a study that required subjects to synchronize with a persistent fractal metronome. The results showed that the model adequately predicted the empirical pattern of results. Our power simulations could be used in conjunction with previous design guidelines in the literature when planning new gait variability experiments. PMID:28323871

  7. Wind energy in electric power production, preliminary study

    NASA Astrophysics Data System (ADS)

    Lento, R.; Peltola, E.

    1984-01-01

    The wind speed conditions in Finland have been studied with the aid of the existing statistics of the Finnish Meteorological Institute. With the aid of the statistics estimates on the available wind energy were also made. Eight hundred wind power plants, 1.5 MW each, on the windiest west coast would produce about 2 TWh energy per year. Far more information on the temporal, geographical and vertical distribution of the wind speed than the present statistics included is needed when the available wind energy is estimated, when wind power plants are dimensioned optimally, and when suitable locations are chosen for them. The investment costs of a wind power plant increase when the height of the tower or the diameter of the rotor is increased, but the energy production increases, too. Thus, overdimensioning the wind power plant in view of energy needs or the wind conditions caused extra costs. The cost of energy produced by wind power can not yet compete with conventional energy, but the situation changes to the advantage of wind energy, if the real price of the plants decreases (among other things due to large series production and increasing experience), or if the real price of fuels rises. The inconvinience on the environment caused by the wind power plants is considered insignificant. The noise caused by the plant attenuates rapidly with distance. No harmful effects to birds and other animals caused by the wind power plants have been observed in the studies made abroad. Parts of the plant getting loose during an accident, or ice forming on the blades are estimated to fly even from a large plant only a few hundred meters.

  8. A Study of Defense Applications of Space Solar Power

    NASA Astrophysics Data System (ADS)

    Jaffe, Paul

    2010-01-01

    Space solar power (SSP) is generally considered to be the collection in space of energy from the sun and its wireless transmission from space for use on earth. It has been observed that the implementation of such a system could offer energy security, environmental, and technological advantages to those who would undertake its development. A study conducted by the Naval Research Laboratory (NRL) sought to determine if unique, cost effective, and efficient approaches exist for supplying significant power on demand for Navy, Marine Corps, or other Department of Defense applications by employing a space-based solar power system. The study was initiated by and prepared for top NRL management in part as a result of the publication of the National Security Space Office's (NSSO) report "Space-Based Solar Power as an Opportunity for Strategic Security." The NSSO report's recommendations included statements calling for the U.S. Government to conduct analyses, retire technical risk, and become an early demonstrator for SBSP. It should be noted that the principal objective of the NRL study differed significantly from that of the multitude of previous studies performed in reference to SBSP in that it focused on defense rather than utility grid applications.

  9. Including History in the Study of Psychological and Political Power

    ERIC Educational Resources Information Center

    Reich, Stephanie M.; Pinkard, Tracy; Davidson, Heather

    2008-01-01

    Isaac Prilleltensky's (2003) concept of psychopolitical validity stresses the need to consider both the political and the psychological nature of power in the study of wellness, oppression, and liberation. The authors advocate that psychopolitical validity would be strengthened if it included an explicit appreciation of historical context. The…

  10. A NUMERICAL study of solar chimney power plants in Tunisia

    NASA Astrophysics Data System (ADS)

    Bahar F, Attig; S, Guellouz M.; M, Sahraoui; S, Kaddeche

    2015-04-01

    A 3D CFD (Computational fluid dynamics) model of a Solar Chimney Power Plant (SCPP) was developed and validated through comparison with the experimental data of the Manzanares plant. Then, it was employed to study the SCPP performance for locations throughout Tunisia.

  11. A Course Case Study: Nuclear Power Generation and the Environment

    ERIC Educational Resources Information Center

    Schlesinger, Allen B.

    1975-01-01

    Describes a course that uses the Ft. Calhoun nuclear power plant as a case study. The course involves three component parts: physics of fission events, engineering requirements, and economic considerations; environmental impact from radiation and thermal effluents; and the impact of social, political and legal factors. (GS)

  12. Space station WP-04 power system. Volume 2: Study results

    NASA Technical Reports Server (NTRS)

    Hallinan, G. J.

    1987-01-01

    Results of the phase B study contract for the definition of the space station Electric Power System (EPS) are presented in detail along with backup information and supporting data. Systems analysis and trades, preliminary design, advanced development, customer accommodations, operations planning, product assurance, and design and development phase planning are addressed. The station design is a hybrid approach which provides user power of 25 kWe from the photovoltaic subsystem and 50 kWe from the solar dynamic subsystem. The electric power is distributed to users as a utility service; single phase at a frequency of 20 kHz and voltage of 440VAC. The solar array NiH2 batteries of the photovoltaic subsystem are based on commonality to those used on the co-orbiting and solar platforms.

  13. Between disorder and order: A case study of power law

    NASA Astrophysics Data System (ADS)

    Cao, Yong; Zhao, Youjie; Yue, Xiaoguang; Xiong, Fei; Sun, Yongke; He, Xin; Wang, Lichao

    2016-08-01

    Power law is an important feature of phenomena in long memory behaviors. Zipf ever found power law in the distribution of the word frequencies. In physics, the terms order and disorder are Thermodynamic or statistical physics concepts originally and a lot of research work has focused on self-organization of the disorder ingredients of simple physical systems. It is interesting what make disorder-order transition. We devise an experiment-based method about random symbolic sequences to research regular pattern between disorder and order. The experiment results reveal power law is indeed an important regularity in transition from disorder to order. About these results the preliminary study and analysis has been done to explain the reasons.

  14. A preliminary study of pulse-laser powered orbital launcher

    NASA Astrophysics Data System (ADS)

    Katsurayama, Hiroshi; Komurasaki, Kimiya; Arakawa, Yoshihiro

    2009-10-01

    An air-breathing pulse-laser powered orbital launcher has been proposed as an alternative to conventional chemical launch systems. The aim of the present study is to assess its feasibility through the estimation of its achievable payload mass per unit beam power and launch cost. A transfer trajectory from the ground to a geosynchronous Earth orbit (GEO) is proposed, and the launch trajectory to its geosynchronous transfer orbit (GTO) is computed using the realistic performance modeled in the pulsejet, ramjet, and rocket flight modes of the launcher. Results show that the launcher can transfer 0.084 kg of payload per 1 MW beam power to a geosynchronous earth orbit. The cost becomes a quarter of existing systems if one can divide a single launch into 24,000 multiple launches.

  15. Interplanetary Magnetic Field Power Spectrum Variations: A VHO Enabled Study

    NASA Technical Reports Server (NTRS)

    Szabo, A.; Koval, A.; Merka, J.; Narock, T.

    2011-01-01

    The newly reprocessed high time resolution (11/22 vectors/sec) Wind mission interplanetary magnetic field data and the solar wind key parameter search capability of the Virtual Heliospheric Observatory (VHO) affords an opportunity to study magnetic field power spectral density variations as a function of solar wind conditions. In the reprocessed Wind Magnetic Field Investigation (MFI) data, the spin tone and its harmonics are greatly reduced that allows the meaningful fitting of power spectra to the 2 Hz limit above which digitization noise becomes apparent. The power spectral density is computed and the spectral index is fitted for the MHD and ion inertial regime separately along with the break point between the two for various solar wind conditions. The time periods of fixed solar wind conditions are obtained from VHO searches that greatly simplify the process. The functional dependence of the ion inertial spectral index and break point on solar wind plasma and magnetic field conditions will be discussed

  16. Interplanetary Magnetic Field Power Spectrum Variations: A VHO Enabled Study

    NASA Technical Reports Server (NTRS)

    Szabo, A.; Koval, A.; Merka, J.; Narock, T.

    2010-01-01

    The newly reprocessed high time resolution (11/22 vectors/sec) Wind mission interplanetary magnetic field data and the solar wind key parameter search capability of the Virtual Heliospheric Observatory (VHO) affords an opportunity to study magnetic field power spectral density variations as a function of solar wind conditions. In the reprocessed Wind Magnetic Field Investigation (MFI) data, the spin tone and its harmonics are greatly reduced that allows the meaningful fitting of power spectra to the approx.2 Hz limit above which digitization noise becomes apparent. The power spectral density is computed and the spectral index is fitted for the MHD and ion inertial regime separately along with the break point between the two for various solar wind conditions . The time periods of fixed solar wind conditions are obtained from VHO searches that greatly simplify the process. The functional dependence of the ion inertial spectral index and break point on solar wind plasma and magnetic field conditions will be discussed

  17. Is clinical measurement of anatomic axis of the femur adequate?

    PubMed

    Wu, Chi-Chuan

    2017-03-23

    Background and purpose - The accuracy of using clinical measurement from the anterior superior iliac spine (ASIS) to the center of the knee to determine an anatomic axis of the femur has rarely been studied. A radiographic technique with a full-length standing scanogram (FLSS) was used to assess the adequacy of the clinical measurement. Patients and methods - 100 consecutive young adult patients (mean age 34 (20-40) years) with chronic unilateral lower extremity injuries were studied. The pelvis and intact contralateral lower extremity images in the FLSS were selected for study. The angles between the tibial axis and the femoral shaft anatomic axis (S-AA), the piriformis anatomic axis (P-AA), the clinical anatomic axis (C-AA), and the mechanical axis (MA) were compared between sexes. Results - Only the S-AA and C-AA angles were statistically significantly different in the 100 patients (3.6° vs. 2.8°; p = 0.03). There was a strong correlation between S-AA, P-AA, and C-AA angles (r > 0.9). The average intersecting angle between MA and S-AA in the femur in the 100 patients was 5.5°, and it was 4.8° between MA and C-AA. Interpretation - Clinical measurement of an anatomic axis from the ASIS to the center of the knee may be an adequate and acceptable method to determine lower extremity alignment. The optimal inlet for antegrade femoral intramedullary nailing may be the lateral edge of the piriformis fossa.

  18. Solar-Powered Europa Orbiter Design Study (2007)

    NASA Technical Reports Server (NTRS)

    Elliott, John; Langmaier, Jerry; Pappalardo, Robert; Strange, Nathan; Spilker, Tom; Lock, Rob; Reh, Kim

    2008-01-01

    The feasibility of implementing a solar-powered mission around Europa has been evaluated periodically over the last decade. Most recently, an assessment was performed as part of the 2006 Europa Explorer (EE) Study, which evaluated the practicality of implementing that mission design with large solar arrays instead of radioisotope power systems (RPS). This previous study went into some depth in considering the issues related to the use of solar arrays in the Europa orbit illumination and radiation environment. The study concluded that an all-solar option was impractical to meet the science objectives as defined in that study by the science team. This conclusion resulted from the prohibitive mass, packaging and articulation issues associated with the very large (approx.300 sq m) solar arrays required to accommodate frequent eclipse periods associated with the particular Europa orbit used.

  19. Regulatory requirements for providing adequate veterinary care to research animals.

    PubMed

    Pinson, David M

    2013-09-01

    Provision of adequate veterinary care is a required component of animal care and use programs in the United States. Program participants other than veterinarians, including non-medically trained research personnel and technicians, also provide veterinary care to animals, and administrators are responsible for assuring compliance with federal mandates regarding adequate veterinary care. All program participants therefore should understand the regulatory requirements for providing such care. The author provides a training primer on the US regulatory requirements for the provision of veterinary care to research animals. Understanding the legal basis and conditions of a program of veterinary care will help program participants to meet the requirements advanced in the laws and policies.

  20. [How many subjects do I need to power my study?].

    PubMed

    Muñoz Navarro, Sergio R

    2014-07-08

    The article presents a tool that helps answer the question “How many subjects do I need to power my study? We show how to determine sample size in observational epidemiological studies and provide examples of application using the statistical package Epidat, which is a shareware program developed under the auspices of the Pan American Health Organization, the Galician Board of Health and the University CES of Colombia. Examples of calculation of sample size for prevalence studies (cross-sectional), case-control studies and cohort studies are given.

  1. Advanced Integrated Power and Attitude Control System (IPACS) study

    NASA Technical Reports Server (NTRS)

    Oglevie, R. E.; Eisenhaure, D. B.

    1985-01-01

    Integrated Power and Attitude Control System (IPACS) studies performed over a decade ago established the feasibility of simultaneously satisfying the demands of energy storage and attitude control through the use of rotating flywheels. It was demonstrated that, for a wide spectrum of applications, such a system possessed many advantages over contemporary energy storage and attitude control approaches. More recent technology advances in composite material rotors, magnetic suspension systems, and power control electronics have triggered new optimism regarding the applicability and merits of this concept. This study is undertaken to define an advanced IPACS and to evaluate its merits for a space station application. System and component designs are developed to establish the performance of this concept and system trade studies conducted to examine the viability of this approach relative to conventional candidate systems. It is clearly demonstrated that an advanced IPACS concept is not only feasible, but also offers substantial savings in mass and life-cycle cost for the space station mission.

  2. Individual and contextual determinants of adequate maternal health care services in Kenya.

    PubMed

    Achia, Thomas N O; Mageto, Lillian E

    2015-01-01

    This study aimed to examine individual and community level factors associated with adequate use of maternal antenatal health services in Kenya. Individual and community level factors associated with adequate use of maternal health care (MHC) services were obtained from the 2008-09 Kenya Demographic and Health Survey data set. Multilevel partial-proportional odds logit models were fitted using STATA 13.0 to quantify the relations of the selected covariates to adequate MHC use, defined as a three-category ordinal variable. The sample consisted of 3,621 women who had at least one live birth in the five-year period preceding this survey. Only 18 percent of the women had adequate use of MHC services. Greater educational attainment by the woman or her partner, higher socioeconomic status, access to medical insurance coverage, and greater media exposure were the individual-level factors associated with adequate use of MHC services. Greater community ethnic diversity, higher community-level socioeconomic status, and greater community-level health facility deliveries were the contextual-level factors associated with adequate use of MHC. To improve the use of MHC services in Kenya, the government needs to design and implement programs that target underlying individual and community level factors, providing focused and sustained health education to promote the use of antenatal, delivery, and postnatal care.

  3. On Adequate Comparisons of Antenna Phase Center Variations

    NASA Astrophysics Data System (ADS)

    Schoen, S.; Kersten, T.

    2013-12-01

    One important part for ensuring the high quality of the International GNSS Service's (IGS) products is the collection and publication of receiver - and satellite antenna phase center variations (PCV). The PCV are crucial for global and regional networks, since they introduce a global scale factor of up to 16ppb or changes in the height component with an amount of up to 10cm, respectively. Furthermore, antenna phase center variations are also important for precise orbit determination, navigation and positioning of mobile platforms, like e.g. the GOCE and GRACE gravity missions, or for the accurate Precise Point Positioning (PPP) processing. Using the EUREF Permanent Network (EPN), Baire et al. (2012) showed that individual PCV values have a significant impact on the geodetic positioning. The statements are further supported by studies of Steigenberger et al. (2013) where the impact of PCV for local-ties are analysed. Currently, there are five calibration institutions including the Institut für Erdmessung (IfE) contributing to the IGS PCV file. Different approaches like field calibrations and anechoic chamber measurements are in use. Additionally, the computation and parameterization of the PCV are completely different within the methods. Therefore, every new approach has to pass a benchmark test in order to ensure that variations of PCV values of an identical antenna obtained from different methods are as consistent as possible. Since the number of approaches to obtain these PCV values rises with the number of calibration institutions, there is the necessity for an adequate comparison concept, taking into account not only the numerical values but also stochastic information and computational issues of the determined PCVs. This is of special importance, since the majority of calibrated receiver antennas published by the IGS origin from absolute field calibrations based on the Hannover Concept, Wübbena et al. (2000). In this contribution, a concept for the adequate

  4. Are Vancomycin Trough Concentrations Adequate for Optimal Dosing?

    PubMed Central

    Youn, Gilmer; Jones, Brenda; Jelliffe, Roger W.; Drusano, George L.; Rodvold, Keith A.; Lodise, Thomas P.

    2014-01-01

    The current vancomycin therapeutic guidelines recommend the use of only trough concentrations to manage the dosing of adults with Staphylococcus aureus infections. Both vancomycin efficacy and toxicity are likely to be related to the area under the plasma concentration-time curve (AUC). We assembled richly sampled vancomycin pharmacokinetic data from three studies comprising 47 adults with various levels of renal function. With Pmetrics, the nonparametric population modeling package for R, we compared AUCs estimated from models derived from trough-only and peak-trough depleted versions of the full data set and characterized the relationship between the vancomycin trough concentration and AUC. The trough-only and peak-trough depleted data sets underestimated the true AUCs compared to the full model by a mean (95% confidence interval) of 23% (11 to 33%; P = 0.0001) and 14% (7 to 19%; P < 0.0001), respectively. In contrast, using the full model as a Bayesian prior with trough-only data allowed 97% (93 to 102%; P = 0.23) accurate AUC estimation. On the basis of 5,000 profiles simulated from the full model, among adults with normal renal function and a therapeutic AUC of ≥400 mg · h/liter for an organism for which the vancomycin MIC is 1 mg/liter, approximately 60% are expected to have a trough concentration below the suggested minimum target of 15 mg/liter for serious infections, which could result in needlessly increased doses and a risk of toxicity. Our data indicate that adjustment of vancomycin doses on the basis of trough concentrations without a Bayesian tool results in poor achievement of maximally safe and effective drug exposures in plasma and that many adults can have an adequate vancomycin AUC with a trough concentration of <15 mg/liter. PMID:24165176

  5. 13 CFR 107.200 - Adequate capital for Licensees.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... operate actively in accordance with your Articles and within the context of your business plan, as... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Adequate capital for Licensees. 107.200 Section 107.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL...

  6. 13 CFR 107.200 - Adequate capital for Licensees.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... operate actively in accordance with your Articles and within the context of your business plan, as... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false Adequate capital for Licensees. 107.200 Section 107.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL...

  7. Is the Stock of VET Skills Adequate? Assessment Methodologies.

    ERIC Educational Resources Information Center

    Blandy, Richard; Freeland, Brett

    In Australia and elsewhere, four approaches have been used to determine whether stocks of vocational education and training (VET) skills are adequate to meet industry needs. The four methods are as follows: (1) the manpower requirements approach; (2) the international, national, and industry comparisons approach; (3) the labor market analysis…

  8. Do Beginning Teachers Receive Adequate Support from Their Headteachers?

    ERIC Educational Resources Information Center

    Menon, Maria Eliophotou

    2012-01-01

    The article examines the problems faced by beginning teachers in Cyprus and the extent to which headteachers are considered to provide adequate guidance and support to them. Data were collected through interviews with 25 school teachers in Cyprus, who had recently entered teaching (within 1-5 years) in public primary schools. According to the…

  9. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  10. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  11. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  12. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  13. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  14. Understanding Your Adequate Yearly Progress (AYP), 2011-2012

    ERIC Educational Resources Information Center

    Missouri Department of Elementary and Secondary Education, 2011

    2011-01-01

    The "No Child Left Behind Act (NCLB) of 2001" requires all schools, districts/local education agencies (LEAs) and states to show that students are making Adequate Yearly Progress (AYP). NCLB requires states to establish targets in the following ways: (1) Annual Proficiency Target; (2) Attendance/Graduation Rates; and (3) Participation…

  15. 34 CFR 200.13 - Adequate yearly progress in general.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false Adequate yearly progress in general. 200.13 Section 200.13 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING THE ACADEMIC ACHIEVEMENT OF THE...

  16. 34 CFR 200.13 - Adequate yearly progress in general.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 1 2013-07-01 2013-07-01 false Adequate yearly progress in general. 200.13 Section 200.13 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING THE ACADEMIC ACHIEVEMENT OF THE...

  17. Region 9: Arizona Adequate Letter (11/1/2001)

    EPA Pesticide Factsheets

    This is a letter from Jack P. Broadbent, Director, Air Division to Nancy Wrona and James Bourney informing them of the adequacy of Revised MAG 1999 Serious Area Carbon Monoxide Plan and that the MAG CO Plan is adequate for Maricopa County.

  18. Contingency Power Study for Short Haul Civil Tiltrotor

    NASA Technical Reports Server (NTRS)

    D'Angelo, Marin M.

    2004-01-01

    NASA has concluded from previous studies that the twin engine tiltrotor is the most economical and technologically viable rotorcraft for near-term civil applications. Twin engine civil rotorcraft must be able to hover safely on one engine in an emergency. This emergency power requirement generally results in engines 20 to 50 percent larger than needed for normal engine operation, negatively impacting aircraft economics. This study identifies several contingency power enhancement concepts, and quantifies their potential to reduce aircraft operating costs. Many unique concepts were examined, and the selected concepts are simple, reliable, and have a high potential for near term realization. These engine concepts allow extremely high turbine temperatures during emergency operation by providing cooling to the power turbine and augmenting cooling of both turbines and structural hardware. Direct operating cost are reduced 3 to percent, which could yield a 30 to 80 percent increase in operating profits. The study consists of the definition of an aircraft economics model and a baseline engine, and an engine concept screening study, and a preliminary definition of the selected concepts. The selected concepts are evaluated against the baseline engine, and the critical technologies and development needs are identified, along with applications for this technology.

  19. Design study of a high power rotary transformer

    NASA Technical Reports Server (NTRS)

    Weinberger, S. M.

    1982-01-01

    A design study was made on a rotary transformer for transferring electrical power across a rotating spacecraft interface. The analysis was performed for a 100 KW, 20 KHz unit having a ""pancake'' geometry. The rotary transformer had a radial (vertical) gap and consisted of 4-25 KW modules. It was assumed that the power conditioning comprised of a Schwarz resonant circuit with a 20 KHz switching frequency. The rotary transformer, mechanical and structural design, heat rejection system and drive mechanism which provide a complete power transfer device were examined. The rotary transformer losses, efficiency, weight and size were compared with an axial (axial symmetric) gap transformer having the same performance requirements and input characteristics which was designed as part of a previous program. The ""pancake'' geometry results in a heavier rotary transformer primarily because of inefficient use of the core material. It is shown that the radial gap rotary transformer is a feasible approach for the transfer of electrical power across a rotating interface and can be implemented using presently available technology.

  20. Functional models of power electronic components for system studies

    NASA Technical Reports Server (NTRS)

    Tam, Kwa-Sur; Yang, Lifeng; Dravid, Narayan

    1991-01-01

    A novel approach to model power electronic circuits has been developed to facilitate simulation studies of system-level issues. The underlying concept for this approach is to develop an equivalent circuit, the functional model, that performs the same functions as the actual circuit but whose operation can be simulated by using larger time step size and the reduction in model complexity, the computation time required by a functional model is significantly shorter than that required by alternative approaches. The authors present this novel modeling approach and discuss the functional models of two major power electronic components, the DC/DC converter unit and the load converter, that are being considered by NASA for use in the Space Station Freedom electric power system. The validity of these models is established by comparing the simulation results with available experimental data and other simulation results obtained by using a more established modeling approach. The usefulness of this approach is demonstrated by incorporating these models into a power system model and simulating the system responses and interactions between components under various conditions.

  1. A 12 GHz RF Power Source for the CLIC Study

    SciTech Connect

    Schirm, Karl; Curt, Stephane; Dobert, Steffen; McMonagle, Gerard; Rossat, Ghislain; Syratchev, Igor; Timeo, Luca; Haase, Andrew Jensen, Aaron; Jongewaard, Erik; Nantista, Christopher; Sprehn, Daryl; Vlieks, Arnold; Hamdi, Abdallah; Peauger, Franck; Kuzikov, Sergey; Vikharev, Alexandr; /Nizhnii Novgorod, IAP

    2012-07-03

    The CLIC RF frequency has been changed in 2008 from the initial 30 GHz to the European X-band 11.9942 GHz permitting beam independent power production using klystrons for CLIC accelerating structure testing. A design and fabrication contract for five klystrons at that frequency has been signed by different parties with SLAC. France (IRFU, CEA Saclay) is contributing a solid state modulator purchased in industry and specific 12 GHz RF network components to the CLIC study. RF pulses over 120 MW peak at 230 ns length will be obtained by using a novel SLED-I type pulse compression scheme designed and fabricated by IAP, Nizhny Novgorod, Russia. The X-band power test stand is being installed in the CLIC Test Facility CTF3 for independent structure and component testing in a bunker, but allowing, in a later stage, for powering RF components in the CTF3 beam lines. The design of the facility, results from commissioning of the RF power source and the expected performance of the Test Facility are reported.

  2. Multi-kw dc power distribution system study program

    NASA Technical Reports Server (NTRS)

    Berkery, E. A.; Krausz, A.

    1974-01-01

    The first phase of the Multi-kw dc Power Distribution Technology Program is reported and involves the test and evaluation of a technology breadboard in a specifically designed test facility according to design concepts developed in a previous study on space vehicle electrical power processing, distribution, and control. The static and dynamic performance, fault isolation, reliability, electromagnetic interference characterisitics, and operability factors of high distribution systems were studied in order to gain a technology base for the use of high voltage dc systems in future aerospace vehicles. Detailed technical descriptions are presented and include data for the following: (1) dynamic interactions due to operation of solid state and electromechanical switchgear; (2) multiplexed and computer controlled supervision and checkout methods; (3) pulse width modulator design; and (4) cable design factors.

  3. Nuclear Power Options Viability Study. Volume 4. Bibliography

    SciTech Connect

    Trauger, D B; White, J D; Sims, J W

    1986-09-01

    Documents in the Nuclear Power Options Viability Study (NPOVS) bibliography are classified under one of four headings or categories as follows: nuclear options; light water reactors; liquid metal reactors; and high temperature reactors. The collection and selection of these documents, beginning early in 1984 and continuing through March of 1986, was carried out in support of the study's objective: to explore the viabilities of several nuclear electric power generation options for commercial deployment in the United States between 2000 and 2010. There are approximately 550 articles, papers, reports, and books in the bibliography that have been selected from some 2000 surveyed. The citations have been made computer accessible to facilitate rapid on-line retrieval by keyword, author, corporate author, title, journal name, or document number.

  4. Solar power satellite system definition study. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Configuration concepts, option sizes, and systems definitions study design evolutions are reviewed. The main features of the present reference design silicon solar cell solar power satellite are described, as well as the provisions for space construction and support systems. The principal study accomplishments and conclusions are summarized according to the following tasks: (1) baseline critique; (2) construction and maintenance; (3) industrial complex needs, cost estimates, and production capacity; (4) launch complex requirements at KSC or at an offshore facility; (5) integration of the SPS/ground power network; (6) technology advancement and development; (7) costs and schedules; and (8) exploratory technology: laser annealing of solar cells degraded by proton irradiation, and a fiber-optic phase distribution link at 980 MHz.

  5. Cost study of solar cell space power systems

    NASA Technical Reports Server (NTRS)

    Bernatowicz, D. T.

    1972-01-01

    Historical costs for solar cell space power systems were evaluated. The study covered thirteen missions that represented a broad cross section of flight projects over the past decade. Fully burdened costs in terms of 1971 dollars are presented for the system and the solar array. The costs correlate reasonably well with array area and do not increase in proportion to array area. The trends for array costs support the contention that solar cell and module standardization reduce costs.

  6. The kW power module evolution study: Executive summary

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Using the Marshall Space Flight Center 25 kW Power Module (PM) reference design as a point of departure, the study defined evolutionary growth paths to 100 kW and above. A recommended development approach and initial configurations were described. Specific hardware changes from the reference design are recommended for the initial PM configuration to ensure evolutionary growth, improved replicability, and reduced cost. Certain functional changes are also recommended to enhance system capabilities.

  7. Study of a Wind Farm Power System: Preprint

    SciTech Connect

    Muljadi, E.; Wan, Y.; Butterfield, C. P.; Parsons, B.

    2002-01-01

    A wind power system differs from a conventional power system. In a conventional power plant, the operator can control the plant's output. The output of a wind farm cannot be controlled because the output fluctuates with the wind. In this paper, we investigate the power-system interaction resulting from power variations at wind farms using steady-state analysis.

  8. Cost study of solar cell space power systems.

    NASA Technical Reports Server (NTRS)

    Bernatowicz, D. T.

    1972-01-01

    A study of historical costs for solar cell space power systems was made by a NASA ad hoc study group. The study covered thirteen missions that represented a broad cross-section of flight projects over the past decade. Fully burdened costs in terms of 1971 dollars are presented for the system and the solar array. The costs correlate reasonably well with array area and do not increase in proportion to array area. The trends for array costs support the contention that solar cell and module standardization would reduce costs.

  9. Studies of Electronic Stopping Powers Using Time of Flight Spectrometry

    SciTech Connect

    Zhang, Yanwen; Weber, William J.

    2004-06-01

    Determination of electronic stopping powers using Time of Flight (ToF) spectrometry have been demonstrated by measuring energy loss of He, O, and Al particles based on a ToF Elastic Recoil Detection Analysis (ERDA) set-up. In transmission geometry, the energy loss of the particles in self-supported stopping foils of C, Si and SiC is measured over a continuous range of energies using the ToF spectrometer. This study emphasizes the difference of the stopping power determination with and without dependence on the Si detector calibration over a wide energy range. By calibrating the Si detector for each channel over the measured energy region, the improved approach eliminates much of the error associated with pulsed height defects and measurement uncertainties of less than 4% are achieved. Stopping powers from this study are compared with limited experimental data from the literature and SRIM (The Stopping and Range of Ions in Matter) 2000 and 2003 predictions. In general, the predicted values are in reasonable agreement with the experimental data, and an improved accuracy of SRIM 2003 over SRIM 2000 can be observed in some cases. Furthermore, Braggs rule is valid in SiC for O and Al over the energy region studied.

  10. Chattanooga Electric Power Board Case Study Distribution Automation

    SciTech Connect

    Glass, Jim; Melin, Alexander M.; Starke, Michael R.

    2016-10-01

    In 2009, the U.S. Department of Energy under the American Recovery and Reinvestment Act (ARRA) awarded a grant to the Chattanooga, Tennessee, Electric Power Board (EPB) as part of the Smart Grid Investment Grant Program. The grant had the objective “to accelerate the transformation of the nation’s electric grid by deploying smart grid technologies.” This funding award enabled EPB to expedite the original smart grid implementation schedule from an estimated 10-12 years to 2.5 years. With this funding, EPB invested heavily in distribution automation technologies including installing over 1,200 automated circuit switches and sensors on 171 circuits. For utilities considering a commitment to distribution automation, there are underlying questions such as the following: “What is the value?” and “What are the costs?” This case study attempts to answer these questions. The primary benefit of distribution automation is increased reliability or reduced power outage duration and frequency. Power outages directly impact customer economics by interfering with business functions. In the past, this economic driver has been difficult to effectively evaluate. However, as this case study demonstrates, tools and analysis techniques are now available. In this case study, the impact on customer costs associated with power outages before and after the implementation of distribution automation are compared. Two example evaluations are performed to demonstrate the benefits: 1) a savings baseline for customers under normal operations1 and 2) customer savings for a single severe weather event. Cost calculations for customer power outages are performed using the US Department of Energy (DOE) Interruption Cost Estimate (ICE) calculator2. This tool uses standard metrics associated with outages and the customers to calculate cost impact. The analysis shows that EPB customers have seen significant reliability improvements from the implementation of distribution automation. Under

  11. Power line harmonic radiation: A systematic study using DEMETER spacecraft

    NASA Astrophysics Data System (ADS)

    Němec, F.; Santolík, O.; Parrot, M.; Berthelier, J. J.

    We present results of a systematic survey of Power line harmonic radiation (PLHR) observed by the DEMETER spacecraft. DEMETER is a French micro-satellite launched in June, 2004 with an altitude of orbit of about 700 km. It is designed specifically to study electromagnetic effects connected with seismic and man-made activity. All available high-resolution burst-mode electromagnetic data measured since the beginning of the mission till July 2006 (altogether about 1650 h of data) have been analyzed using an automatic identification procedure. This procedure was specially developed to search for emissions of PLHR type. It is running in DEMETER control center in Orléans, France. 49 PLHR events with frequency spacing of 50/100 or 60/120 Hz have been found, allowing us to perform a statistical study of properties of PLHR. It is shown that for all the events, the observed frequency spacing corresponds well to the power system frequency at anticipated source locations. Moreover, the frequency of the observed lines often (80%) corresponds to the exact harmonics of the power system base frequency. Finally, the most intense events are observed at lower frequencies and no weak events are observed under geomagnetically disturbed conditions.

  12. A thermal study of power cables cooling in tunnels

    NASA Astrophysics Data System (ADS)

    Boukrouche, F.; Moreau, C.; Harmand, S.; Beaubert, F.; Pellé, J.; Moreau, O.

    2016-09-01

    Power transmission through power cables installed in ventilated tunnels has been increasingly used worldwide and offers a complex thermal environment. Established correlations currently in use have been deduced from a non-fully developed turbulent flow. This paper details the experimental investigation of the heat transfer from a single cable in a fully developed turbulent air flow, with emphasis on the effect of the cable spacing from the tunnel wall. Nusselt numbers have been compared for different spacing and velocities. The overall heat transfer is found to be meaningfully lower than in previous studies and no threshold spacing value for the average heat transfer to decrease is clearly found. Thermal radiation is found to greatly impact the cable cooling profile.

  13. Study on Cracking Process of Power Boiler Element

    NASA Astrophysics Data System (ADS)

    Mutwil, K.; Cieśla, M.

    2012-05-01

    This paper presents the study of the reasons for cracking of spray steam attemperator. The element being analysed is a temperature controller of steam for turbine; its proper functioning has considerable impact on operation of power generating set of boiler and turbine. Damage to the steam attemperator may affect the durability of neighbouring components, replacement or repair of which results in a long-term outage of power generation unit. The reason for attemperator cracking has been determined on the basis of strength calculations and micro-and macro-analysis of fracture surfaces. The conducted tests were the basis for modification of attemperator design, which will ensure reliable functioning of the analysed element.

  14. Army General Fund Adjustments Not Adequately Documented or Supported

    DTIC Science & Technology

    2016-07-26

    statements were unreliable and lacked an adequate audit trail. Furthermore, DoD and Army managers could not rely on the data in their accounting...risk that AGF financial statements will be materially misstated and the Army will not achieve audit readiness by the congressionally mandated...and $6.5 trillion in yearend adjustments made to Army General Fund data during FY 2015 financial statement compilation. We conducted this audit in

  15. Reply to the 'Comment on "trans-1,2-Disiloxybenzocyclobutene, an adequate partner for the auto-oxidation: EPR/spin trapping and theoretical studies"' by H.-G. Korth, P. Mulder and T. Paul, Phys. Chem. Chem. Phys., 2017, 19, C6CP04187F.

    PubMed

    Carissan, Yannick; Nava, Paola; Tuccio, Béatrice; Commeiras, Laurent; Parrain, Jean-Luc

    2017-01-25

    The proposal and the comments made by Korth et al. on a biradical intermediate along the isomerization path of the reaction of trans-1,2-tert-butyldimethyldisilyloxybenzocyclobutene 1 with dioxygen are unsuitable in our case. The mechanism scenario that we proposed is in agreement with our experimental observations. Moreover, new calculations were able to give an answer to the crucial question, "is the biradical an intermediate or a transition state?" together with the localization of the two radicals. This full article is a response to the "Comment on "trans-1,2-Disiloxybenzocyclobutene, an adequate partner for the auto-oxidation: EPR/spin trapping and theoretical studies" by J. Drujon et al., Phys. Chem. Chem. Phys. 2014, 16, 7513".

  16. Power analysis of principal components regression in genetic association studies.

    PubMed

    Shen, Yan-feng; Zhu, Jun

    2009-10-01

    Association analysis provides an opportunity to find genetic variants underlying complex traits. A principal components regression (PCR)-based approach was shown to outperform some competing approaches. However, a limitation of this method is that the principal components (PCs) selected from single nucleotide polymorphisms (SNPs) may be unrelated to the phenotype. In this article, we investigate the theoretical properties of such a method in more detail. We first derive the exact power function of the test based on PCR, and hence clarify the relationship between the test power and the degrees of freedom (DF). Next, we extend the PCR test to a general weighted PCs test, which provides a unified framework for understanding the properties of some related statistics. We then compare the performance of these tests. We also introduce several data-driven adaptive alternatives to overcome difficulties in the PCR approach. Finally, we illustrate our results using simulations based on real genotype data. Simulation study shows the risk of using the unsupervised rule to determine the number of PCs, and demonstrates that there is no single uniformly powerful method for detecting genetic variants.

  17. Inertial confinement fusion reaction chamber and power conversion system study

    SciTech Connect

    Maya, I.; Schultz, K.R.; Battaglia, J.M.; Buksa, J.J.; Creedson, R.L.; Erlandson, O.D.; Levine, H.E.; Roelant, D.F.; Sanchez, H.W.; Schrader, S.A.

    1984-09-01

    GA Technologies has developed a conceptual ICF reactor system based on the Cascade rotating-bed reaction chamber concept. Unique features of the system design include the use of low activation SiC in a reaction chamber constructed of box-shaped tiles held together in compression by prestressing tendons to the vacuum chamber. Circulating Li/sub 2/O granules serve as the tritium breeding and energy transport material, cascading down the sides of the reaction chamber to the power conversion system. The total tritium inventory of the system is 6 kg; tritium recovery is accomplished directly from the granules via the vacuum system. A system for centrifugal throw transport of the hot Li/sub 2/O granules from the reaction chamber to the power conversion system has been developed. A number of issues were evaluated during the course of this study. These include the response of first-layer granules to the intense microexplosion surface heat flux, cost effective fabrication of Li/sub 2/O granules, tritium inventory and recovery issues, the thermodynamics of solids-flow options, vacuum versus helium-medium heat transfer, and the tradeoffs of capital cost versus efficiency for alternate heat exchange and power conversion system option. The resultant design options appear to be economically competitive, safe, and environmentally attractive.

  18. Effect of tranquilizers on animal resistance to the adequate stimuli of the vestibular apparatus

    NASA Technical Reports Server (NTRS)

    Maksimovich, Y. B.; Khinchikashvili, N. V.

    1980-01-01

    The effect of tranquilizers on vestibulospinal reflexes and motor activity was studied in 900 centrifuged albino mice. Actometric studies have shown that the tranquilizers have a group capacity for increasing animal resistance to the action of adequate stimuli to the vestibular apparatus.

  19. (Findings of the Costa Rica power sector efficiency study)

    SciTech Connect

    Waddle, D.B.

    1990-10-08

    To present findings of the Costa Rica Power Sector Efficiency Study to the Instituto Costarricense de Electridad, and to the Ministry of Energy, Natural Resources and Mining. To discuss the progress and plans for the Central American Rural Electrification Project with US Agency for International Development (USAID)/Regional Office Central American Program (ROCAP). I traveled to San Jose, Costa Rica to present the findings of the Costa Rica Power Sector Efficiency Study to our counterparts in the utility and the Ministry of Energy. Discussions were held with line level managers at Instituto Costarricensede Electricidad (ICE) and Ministry of Energy Mines and Natural Resources (MIRENEM), as well as a plan of action set for the final stage of the project. Discussions were held for a one day period with both the bilateral Agency for International Development (AID) and the regional AID mission regarding the need for a similar study in Guatemala and matters directly pertaining to the Central American Rural Electrification Study (CARES) project.

  20. Integrated Power/Attitude Control System (IPACS) study. Volume 1: Feasibility studies. [application of flywheels for power storage and generation

    NASA Technical Reports Server (NTRS)

    Notti, J. E.; Cormack, A., III; Schmill, W. C.

    1974-01-01

    An Integrated Power/Attitude Control System (IPACS) concept consisting of an array of spinning flywheels, with or without gimbals, capable of performing the dual function of power storage and generation, as well as attitude control has been investigated. This system provides attitude control through momentum storage, and replaces the storage batteries onboard the spacecraft. The results of the investigation are presented in two volumes. The trade-off studies performed to establish the feasibility, cost effectiveness, required level of development, and boundaries of application of IPACS to a wide variety of spacecraft are discussed. The conceptual designs for a free-flying research application module (RAM), and for a tracking and data relay satellite (TDRS) are presented. Results from dynamic analyses and simulations of the IPACS conceptual designs are included.

  1. Solar power satellite system definition study, volume 4, phase 2

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Results of an overall evaluation of the solar power satellite concept are reported. Specific topics covered include: solid state sandwich configuration; parametric development of reliability design; power distribution system for solid state solar power satellites; multibeam transmission; GEO base system configuration; suppression of the heavy lift launch vehicle trajectory; conceptual design of an offshore space center facility; solar power satellite development and operations scenario; and microwave power transmission technology, advancement, development, and facility requirements.

  2. The Iranian Revolution: A Case Study in Coercive Power Consolidation

    DTIC Science & Technology

    1994-03-01

    insurgents," Times, January 4, 1982, p. 4. ඏ"Bahais executed in Iran," Times, January 9, 1982, p. 5. ඖ Ibid. 172 Baha ’ i sources, the Iranian government...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA L-n I tA DTIC tFLEC.TETHESIS S 10 1994 S~E THE IRANIAN REVOLUTION: A CASE STUDY IN COERCIVE POWER...reverse if necessary and adenuJy by block number) MEW GROUP SUBGROUP Iran, Iranian Revolution, Islam. Middle East. Middle Eastern Politics, Middle I

  3. Neutronic design studies for an unattended, low power reactor

    SciTech Connect

    Palmer, R.G.; Durkee, J.W. Jr.

    1986-01-01

    The Los Alamos National Laboratory is involved in the design and demonstrations of a small, long-lived nuclear heat and electric power source for potential applications at remote sites where alternate fossil energy systems would not be cost effective. This paper describes the neutronic design analysis that was performed to arrive at two conceptual designs, one using thermoelectric conversion, the other using an organic Rankine cycle. To meet the design objectives and constraints a number of scoping and optimization studies were carried out. The results of calculations of control worths, temperature coefficients of reactivity and fuel depletion effects are reported.

  4. Study of novel concepts of power transmission gears

    NASA Technical Reports Server (NTRS)

    Rivin, Eugene I.

    1991-01-01

    Two concepts in power transmission gear design are proposed which provide a potential for large noise reduction and for improving weight to payload ratio due to use of advanced fiber reinforced and ceramic materials. These concepts are briefly discussed. Since both concepts use ultrathin layered rubber-metal laminates for accommodating limited travel displacements, properties of the laminates, such as their compressive strength, compressive and shear moduli were studied. Extensive testing and computational analysis were performed on the first concept gears (laminate coated conformal gears). Design and testing of the second conceptual design (composite gear with separation of sliding and rolling motions) are specifically described.

  5. Importance of adequate exercise in the detection of coronary heart disease by radionuclide ventriculography

    SciTech Connect

    Brady, T.J.; Thrall, J.H.; Lo, K.; Pitt, B.

    1980-12-01

    Rest and exercise radionuclide ventriculograms were obtained on 77 symptomatic patients without prior documented coronary artery disease (CAD). Coronary artery disease was present by angiograms in 48. Radionuclide ventriculography (RNV) was abnormal in 41 patients (overall sensitivity 85%). In 29 patients with normal coronary arteries, RNV was normal in 24 (specificity 83%). To determine if the exercise level affects sensitivity, the studies were graded for adequacy of exercise. It was considered adequate if patients developed (a) chest pain, or (b) ST segment depression of at least 1 mm, or (c) if they achieved a pressure rate product greater than 250. Among the 48 patients with coronary artery disease, 35 achieved adequate exercise. Thirty-three had an abnormal RNV (sensitivity 94%). In 13 patients who failed to achieve adequate exercise, RNV was abnormal in eight (sensitivity of only 62%). Some patients with coronary artery disease may have a normal ventricular response at inadequate levels of stress.

  6. [Prevention of ocular complications of herpes zoster ophthalmicus by adequate treatment with acyclovir].

    PubMed

    Borruat, F X; Buechi, E R; Piguet, B; Fitting, P; Zografos, L; Herbort, C P

    1991-05-01

    We compared the frequency of severe ocular complications secondary to Herpes Zoster Ophthalmicus (HZO) in 232 patients. They were divided into three groups: 1) patients without treatment (n = 164); 2) patients treated adequately (n = 48) with acyclovir (ACV; 5 x 800 mg/d orally and ophthalmic ointment 5 x /d for a minimum of 7 days, given within three days after skin eruption); and, 3) patients treated inadequately (n = 20) with ACV (only topical treatment, insufficient doses, interrupted treatment, delayed treatment). Patients with no treatment or with inadequate treatments showed the same frequency of severe ocular complications (21% (34/164) and 25% (5/20), respectively). In contrast, when adequate treatment of ACV was given complications occurred in only 4% (2/48) of cases. This study emphasizes the need for prompt (within three days after skin eruption) and adequate (5 x 800 mg/d for at least 7 days) treatment of ACV to prevent the severe complications of HZO.

  7. Genetic modification of preimplantation embryos: toward adequate human research policies.

    PubMed

    Dresser, Rebecca

    2004-01-01

    Citing advances in transgenic animal research and setbacks in human trials of somatic cell genetic interventions, some scientists and others want to begin planning for research involving the genetic modification of human embryos. Because this form of genetic modification could affect later-born children and their offspring, the protection of human subjects should be a priority in decisions about whether to proceed with such research. Yet because of gaps in existing federal policies, embryo modification proposals might not receive adequate scientific and ethical scrutiny. This article describes current policy shortcomings and recommends policy actions designed to ensure that the investigational genetic modification of embryos meets accepted standards for research on human subjects.

  8. Elements for adequate informed consent in the surgical context.

    PubMed

    Abaunza, Hernando; Romero, Klaus

    2014-07-01

    Given a history of atrocities and violations of ethical principles, several documents and regulations have been issued by a wide variety of organizations. They aim at ensuring that health care and clinical research adhere to defined ethical principles. A fundamental component was devised to ensure that the individual has been provided the necessary information to make an informed decision regarding health care or participation in clinical research. This article summarizes the history and regulations for informed consent and discusses suggested components for adequate consent forms for daily clinical practice in surgery as well as clinical research.

  9. Satellite Power Systems (SPS) concept definition study. Volume 5: Special emphasis studies. [rectenna and solar power satellite design studies

    NASA Technical Reports Server (NTRS)

    Hanley, G. M.

    1980-01-01

    Satellite configurations based on the Satellite Power System baseline requirements were analyzed and a preferred concept selected. A satellite construction base was defined, precursor operations incident to establishment of orbital support facilities identified, and the satellite construction sequence and procedures developed. Rectenna construction requirement were also addressed. Mass flow to orbit requirements were revised and traffic models established based on construction of 60 instead of 120 satellites. Analyses were conducted to determine satellite control, resources, manufacturing, and propellant requirements. The impact of the laser beam used for space-to-Earth power transmission upon the intervening atmosphere was examined as well as the inverse effect. The significant space environments and their effects on spacecraft components were investigated to define the design and operational limits imposed by the environments on an orbit transfer vehicle. The results show that LEO altitude 300 nmi and transfer orbit duration 6 months are preferrable.

  10. Learning Platform for Study of Power Electronic Application in Power Systems

    ERIC Educational Resources Information Center

    Bauer, P.; Rompelman, O.

    2005-01-01

    Present engineering has to deal with increasingly complex systems. In particular, this is the case in electrical engineering. Though this is obvious in microelectronics, also in the field of power systems engineers have to design, operate and maintain highly complex systems such as power grids, energy converters and electrical drives. This is…

  11. Towards Defining Adequate Lithium Trials for Individuals with Mental Retardation and Mental Illness.

    ERIC Educational Resources Information Center

    Pary, Robert J.

    1991-01-01

    Use of lithium with mentally retarded individuals with psychiatric conditions and/or behavior disturbances is discussed. The paper describes components of an adequate clinical trial and reviews case studies and double-blind cases. The paper concludes that aggression is the best indicator for lithium use, and reviews treatment parameters and…

  12. Perceptions of Teachers in Their First Year of School Restructuring: Failure to Make Adequate Yearly Progress

    ERIC Educational Resources Information Center

    Moser, Sharon

    2010-01-01

    The 2007-2008 school year marked the first year Florida's Title I schools that did not made Adequate Yearly Progress (AYP) for five consecutive years entered into restructuring as mandated by the "No Child Left Behind Act" of 2001. My study examines the perceptions of teacher entering into their first year of school restructuring due to…

  13. Solar power satellite system definition study, volume 7

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Guidelines and assumptions used in the design of a system of geosynchronous satellites for transmitting solar power to earth were discussed as well as the design evolutions of the principle types of solar power satellites and space support systems.

  14. Practical Uses of Statistical Power in Business Research Studies.

    ERIC Educational Resources Information Center

    Markowski, Edward P.; Markowski, Carol A.

    1999-01-01

    Proposes the use of statistical power subsequent to the results of hypothesis testing in business research. Describes how posttest use of power might be integrated into business statistics courses. (SK)

  15. Study Integrated DC Power System Complex AMR-36B,

    DTIC Science & Technology

    GUIDED MISSILES, GROUND SUPPORT EQUIPMENT), (*POWER SUPPLIES, INTEGRATED SYSTEMS), LAUNCHING SITES, POWER EQUIPMENT, ELECTRIC CABLES, TELEMETER...SYSTEMS, ELECTRIC CONNECTORS, DISCONNECT FITTINGS, ALKALINE BATTERIES, ELECTROLYTES, ELECTROLYTIC CELLS, STORAGE BATTERIES, WATER ACTIVATED BATTERIES, FUSES( ELECTRICAL ), STATISTICAL ANALYSIS.

  16. Quantifying dose to the reconstructed breast: Can we adequately treat?

    SciTech Connect

    Chung, Eugene; Marsh, Robin B.; Griffith, Kent A.; Moran, Jean M.; Pierce, Lori J.

    2013-04-01

    To evaluate how immediate reconstruction (IR) impacts postmastectomy radiotherapy (PMRT) dose distributions to the reconstructed breast (RB), internal mammary nodes (IMN), heart, and lungs using quantifiable dosimetric end points. 3D conformal plans were developed for 20 IR patients, 10 autologous reconstruction (AR), and 10 expander-implant (EI) reconstruction. For each reconstruction type, 5 right- and 5 left-sided reconstructions were selected. Two plans were created for each patient, 1 with RB coverage alone and 1 with RB + IMN coverage. Left-sided EI plans without IMN coverage had higher heart Dmean than left-sided AR plans (2.97 and 0.84 Gy, p = 0.03). Otherwise, results did not vary by reconstruction type and all remaining metrics were evaluated using a combined AR and EI dataset. RB coverage was adequate regardless of laterality or IMN coverage (Dmean 50.61 Gy, D95 45.76 Gy). When included, IMN Dmean and D95 were 49.57 and 40.96 Gy, respectively. Mean heart doses increased with left-sided treatment plans and IMN inclusion. Right-sided treatment plans and IMN inclusion increased mean lung V{sub 20}. Using standard field arrangements and 3D planning, we observed excellent coverage of the RB and IMN, regardless of laterality or reconstruction type. Our results demonstrate that adequate doses can be delivered to the RB with or without IMN coverage.

  17. Think Global, Act Local--A Power Generation Case Study

    ERIC Educational Resources Information Center

    Dugdale, Pam

    2012-01-01

    This paper describes an exercise completed by sixth form college students to compare the power output from a local coal fired power station with the potential power output from renewable sources including wind farms, solar farms, and the proposed Mersey Tidal Barrage scheme. (Contains 1 figure, 1 table, and 3 photos.)

  18. Study on heat pipe sink for cooling high power LED

    NASA Astrophysics Data System (ADS)

    Wang, Zhibin; Zhang, Yuebin; Wang, Zhongdong; Xie, Shasha; Hao, Yang

    2012-10-01

    Considering the characteristic of energy-saving about high power LED device, a method to decrease the junction temperature greatly under the natural convection condition is studied in this article. Using the heat pipe technology, a cooling system is designed in which the target heat source is the LED module (0.025m×0.025m×0.005m), with 30W input power. The mechanism and routes of heat transfer are analyzed in detail, the thermal network model is established to calculate the thermal resistance of each part in the cooling system, the total thermal resistance was calculated to be 0.8964°C /W and the junction temperature was 47.39°C . Meanwhile, the finite element method was used to simulate this cooling system, and got that the junction temperature was 47.54°C , and the error of the two means is only 0.15°C , it indicates that applying heat-pipe technology can solve the problem of high junction temperature in LED devices under the natural convection conditions, which can guide the actual project in the thermal design.

  19. Review of avian mortality studies at concentrating solar power plants

    NASA Astrophysics Data System (ADS)

    Ho, Clifford K.

    2016-05-01

    This paper reviews past and current avian mortality studies at concentrating solar power (CSP) plants and facilities including Solar One in California, the Solar Energy Development Center in Israel, Ivanpah Solar Electric Generating System in California, Crescent Dunes in Nevada, and Gemasolar in Spain. Findings indicate that the leading causes of bird deaths at CSP plants are from collisions (primarily with reflective surfaces; i.e., heliostats) and singeing caused by concentrated solar flux. Safe irradiance levels for birds have been reported to range between 4 and 50 kW/m2. Above these levels, singeing and irreversible damage to the feathers can occur. Despite observations of large numbers of "streamers" in concentrated flux regions and reports that suggest these streamers indicate complete vaporization of birds, analyses in this paper show that complete vaporization of birds is highly improbable, and the observed streamers are likely due to insects flying into the concentrated flux. The levelized avian mortality rate during the first year of operation at Ivanpah was estimated to be 0.7 - 3.5 fatalities per GWh, which is less than the levelized avian mortality reported for fossil fuel plants but greater than that for nuclear and wind power plants. Mitigation measures include acoustic, visual, tactile, and chemosensory deterrents to keep birds away from the plant, and heliostat aiming strategies that reduce the solar flux during standby.

  20. Study on Atomization Characteristics for Power Generation Application

    NASA Astrophysics Data System (ADS)

    Anwar, Z. M.; Tan, E. S.; Adnan, R.; Azree Idris, Mohd

    2013-06-01

    The world is dependent on two common basic needs which is electricity and water supply. Thus, power generation is the pulse of a country's econmony. However, most of today's power is generated from fossil fuel which is non sustainable. This research aims to study the feasibility of biodiesel to substitute diesel fuel for gas turbine application. The objective is to investigate the atomization characteristics using various blend of biodiesel derived from transesterification of palm oil. There are five types of fuels tested which are pure Diesel, B20, B50, B80 and B100 which were experimentally tested in a spray atomizer to evaluate the relationship of the of the fuel blend ratio with atomization characteristics such as spray cone angle, spray tip penetration and Sauter Mean Diameter. Besides that, fuel chemical properties testing were conducted to ensure the fuel chemical properties for tested fuel meet the standard requirements for gas turbine fuel oil. Result shows that the higher blend of biodiesel will give larger SMD, longer spray tip penetration, and a smaller spray cone angle. The SMD was calculated based on a general equation. Meanwhile, spray angle and spray tip was obtained from photos captured and anlayzed using software.

  1. 2007 Wholesale Power Rate Case Initial Proposal : Risk Analysis Study.

    SciTech Connect

    United States. Bonneville Power Administration.

    2005-11-01

    The Federal Columbia River Power System (FCRPS), operated on behalf of the ratepayers of the PNW by BPA and other Federal agencies, faces many uncertainties during the FY 2007-2009 rate period. Among these uncertainties, the largest revolve around hydro conditions, market prices and river operations for fish recovery. In order to provide a high probability of making its U.S. Treasury payments, BPA performs a Risk Analysis as part of its rate-making process. In this Risk Analysis, BPA identifies key risks, models their relationships, and then analyzes their impacts on net revenues (total revenues less expenses). BPA subsequently evaluates in the ToolKit Model the Treasury Payment Probability (TPP) resulting from the rates, risks, and risk mitigation measures described here and in the Wholesale Power Rate Development Study (WPRDS). If the TPP falls short of BPA's standard, additional risk mitigation revenues, such as PNRR and CRAC revenues are incorporated in the modeling in ToolKit until the TPP standard is met. Increased wholesale market price volatility and six years of drought have significantly changed the profile of risk and uncertainty facing BPA and its stakeholders. These present new challenges for BPA in its effort to keep its power rates as low as possible while fully meeting its obligations to the U.S. Treasury. As a result, the risk BPA faces in not receiving the level of secondary revenues that have been credited to power rates before receiving those funds is greater. In addition to market price volatility, BPA also faces uncertainty around the financial impacts of operations for fish programs in FY 2006 and in the FY 2007-2009 rate period. A new Biological Opinion or possible court-ordered change to river operations in FY 2006 through FY 2009 may reduce BPA's net revenues included Initial Proposal. Finally, the FY 2007-2009 risk analysis includes new operational risks as well as a more comprehensive analysis of non-operating risks. Both the operational

  2. Precise ablation of dental hard tissues with ultra-short pulsed lasers. Preliminary exploratory investigation on adequate laser parameters.

    PubMed

    Bello-Silva, Marina Stella; Wehner, Martin; Eduardo, Carlos de Paula; Lampert, Friedrich; Poprawe, Reinhart; Hermans, Martin; Esteves-Oliveira, Marcella

    2013-01-01

    This study aimed to evaluate the possibility of introducing ultra-short pulsed lasers (USPL) in restorative dentistry by maintaining the well-known benefits of lasers for caries removal, but also overcoming disadvantages, such as thermal damage of irradiated substrate. USPL ablation of dental hard tissues was investigated in two phases. Phase 1--different wavelengths (355, 532, 1,045, and 1,064 nm), pulse durations (picoseconds and femtoseconds) and irradiation parameters (scanning speed, output power, and pulse repetition rate) were assessed for enamel and dentin. Ablation rate was determined, and the temperature increase measured in real time. Phase 2--the most favorable laser parameters were evaluated to correlate temperature increase to ablation rate and ablation efficiency. The influence of cooling methods (air, air-water spray) on ablation process was further analyzed. All parameters tested provided precise and selective tissue ablation. For all lasers, faster scanning speeds resulted in better interaction and reduced temperature increase. The most adequate results were observed for the 1064-nm ps-laser and the 1045-nm fs-laser. Forced cooling caused moderate changes in temperature increase, but reduced ablation, being considered unnecessary during irradiation with USPL. For dentin, the correlation between temperature increase and ablation efficiency was satisfactory for both pulse durations, while for enamel, the best correlation was observed for fs-laser, independently of the power used. USPL may be suitable for cavity preparation in dentin and enamel, since effective ablation and low temperature increase were observed. If adequate laser parameters are selected, this technique seems to be promising for promoting the laser-assisted, minimally invasive approach.

  3. STARFIRE: a commercial tokamak fusion power plant study

    SciTech Connect

    Not Available

    1980-09-01

    STARFIRE is a 1200 MWe central station fusion electric power plant that utilizes a deuterium-tritium fueled tokamak reactor as a heat source. Emphasis has been placed on developing design features which will provide for simpler assembly and maintenance, and improved safety and environmental characteristics. The major features of STARFIRE include a steady-state operating mode based on continuous rf lower-hybrid current drive and auxiliary heating, solid tritium breeder material, pressurized water cooling, limiter/vacuum system for impurity control and exhaust, high tritium burnup and low vulnerable tritium inventories, superconducting EF coils outside the superconducting TF coils, fully remote maintenance, and a low-activation shield. A comprehensive conceptual design has been developed including reactor features, support facilities and a complete balance of plant. A construction schedule and cost estimate are presented, as well as study conclusions and recommendations.

  4. Aerial thermography studies of power plant heated lakes

    SciTech Connect

    Villa-Aleman, E.

    2000-01-26

    Remote sensing temperature measurements of water bodies is complicated by the temperature differences between the true surface or skin water and the bulk water below. Weather conditions control the reduction of the skin temperature relative to the bulk water temperature. Typical skin temperature depressions range from a few tenths of a degree Celsius to more than one degree. In this research project, the Savannah River Technology Center (SRTC) used aerial thermography and surface-based meteorological and water temperature measurements to study a power plant cooling lake in South Carolina. Skin and bulk water temperatures were measured simultaneously for imagery calibration and to produce a database for modeling of skin temperature depressions as a function of weather and bulk water temperatures. This paper will present imagery that illustrates how the skin temperature depression was affected by different conditions in several locations on the lake and will present skin temperature modeling results.

  5. CENTER FOR PULSED POWER DRIVEN HIGH ENERGY DENSITY PLASMA STUDIES

    SciTech Connect

    Professor Bruce R. Kusse; Professor David A. Hammer

    2007-04-18

    This annual report summarizes the activities of the Cornell Center for Pulsed-Power-Driven High-Energy-Density Plasma Studies, for the 12-month period October 1, 2005-September 30, 2006. This period corresponds to the first year of the two-year extension (awarded in October, 2005) to the original 3-year NNSA/DOE Cooperative Agreement with Cornell, DE-FC03-02NA00057. As such, the period covered in this report also corresponds to the fourth year of the (now) 5-year term of the Cooperative Agreement. The participants, in addition to Cornell University, include Imperial College, London (IC), the University of Nevada, Reno (UNR), the University of Rochester (UR), the Weizmann Institute of Science (WSI), and the P.N. Lebedev Physical Institute (LPI), Moscow. A listing of all faculty, technical staff and students, both graduate and undergraduate, who participated in Center research activities during the year in question is given in Appendix A.

  6. The ARIES Advanced and Conservative Tokamak Power Plant Study

    DOE PAGES

    Kessel, C. E; Tillak, M. S; Najmabadi, F.; ...

    2015-12-22

    Tokamak power plants are studied with advanced and conservative design philosophies to identify the impacts on the resulting designs and to provide guidance to critical research needs. Incorporating updated physics understanding and using more sophisticated engineering and physics analysis, the tokamak configurations have developed a more credible basis compared with older studies. The advanced configuration assumes a self-cooled lead lithium blanket concept with SiC composite structural material with 58% thermal conversion efficiency. This plasma has a major radius of 6.25 m, a toroidal field of 6.0 T, a q₉₅ of 4.5, aᵦtotal N of 5.75, an H98 of 1.65, anmore » n/nGr of 1.0, and a peak divertor heat flux of 13.7 MW/m² . The conservative configuration assumes a dual-coolant lead lithium blanket concept with reduced activation ferritic martensitic steel structural material and helium coolant, achieving a thermal conversion efficiency of 45%. The plasma has a major radius of 9.75 m, a toroidal field of 8.75 T, a q₉₅ of 8.0, aᵦtotalN of 2.5, an H₉₈ of 1.25, an n/nGr of 1.3, and a peak divertor heat flux of 10 MW/m² . The divertor heat flux treatment with a narrow power scrape off width has driven the plasmas to larger major radius. Edge and divertor plasma simulations are targeting a basis for high radiated power fraction in the divertor, which is necessary for solutions to keep the peak heat flux in the range 10 to 15 MW/m² . Combinations of the advanced and conservative approaches show intermediate sizes. A new systems code using a database approach has been used and shows that the operating point is really an operating zone with some range of plasma and engineering parameters and very similar costs of electricity. Other papers in this issue provide more detailed discussion of the work summarized here.« less

  7. The ARIES Advanced and Conservative Tokamak Power Plant Study

    SciTech Connect

    Kessel, C. E; Tillak, M. S; Najmabadi, F.; Poli, F. M.; Ghantous, K.; Gorelenkov, N.; Wang, X. R.; Navaei, D.; Toudeshki, H. H.; Koehly, C.; EL-Guebaly, L.; Blanchard, J. P.; Martin, C. J.; Mynsburge, L.; Humrickhouse, P.; Rensink, M. E.; Rognlien, T. D.; Yoda, M.; Abdel-Khalik, S. I.; Hageman, M. D.; Mills, B. H.; Rader, J. D.; Sadowski, D. L.; Snyder, P. B.; St. John, H.; Turnbull, A. D.; Waganer, L. M.; Malang, S.; Rowcliffe, A. F.

    2015-12-22

    Tokamak power plants are studied with advanced and conservative design philosophies to identify the impacts on the resulting designs and to provide guidance to critical research needs. Incorporating updated physics understanding and using more sophisticated engineering and physics analysis, the tokamak configurations have developed a more credible basis compared with older studies. The advanced configuration assumes a self-cooled lead lithium blanket concept with SiC composite structural material with 58% thermal conversion efficiency. This plasma has a major radius of 6.25 m, a toroidal field of 6.0 T, a q₉₅ of 4.5, aᵦtotal N of 5.75, an H98 of 1.65, an n/nGr of 1.0, and a peak divertor heat flux of 13.7 MW/m² . The conservative configuration assumes a dual-coolant lead lithium blanket concept with reduced activation ferritic martensitic steel structural material and helium coolant, achieving a thermal conversion efficiency of 45%. The plasma has a major radius of 9.75 m, a toroidal field of 8.75 T, a q₉₅ of 8.0, aᵦtotalN of 2.5, an H₉₈ of 1.25, an n/nGr of 1.3, and a peak divertor heat flux of 10 MW/m² . The divertor heat flux treatment with a narrow power scrape off width has driven the plasmas to larger major radius. Edge and divertor plasma simulations are targeting a basis for high radiated power fraction in the divertor, which is necessary for solutions to keep the peak heat flux in the range 10 to 15 MW/m² . Combinations of the advanced and conservative approaches show intermediate sizes. A new systems code using a database approach has been used and shows that the operating point is really an operating zone with some range of plasma and engineering parameters and very similar costs of electricity. Other papers in this issue provide more detailed discussion of the work summarized here.

  8. The ARIES Advanced And Conservative Tokamak (ACT) Power Plant Study

    SciTech Connect

    Kessel, C. E.; Poli, F. M.; Ghantous, K.; Gorelenkov, N.; Tillack, M. S.; Najmabadi, F.; Wang, X. R.; Navaei, D.; Toudeshki, H. H.; Koehly, C.; El-Guebaly, L.; Blanchard, J. P.; Martin, C. J.; Mynsburge, L.; Humrickhouse, P.; Rensink, M. E.; Rognlien, T. D.; Yoda, M.; Abdel-Khalik, S. I.; Hageman, M. D.; Mills, B. H.; Radar, J. D.; Sadowski, D. L.; Snyder, P. B.; St. John, H.; Turnbull, A. D.; Waganer, L. M.; Malang, S.; Rowcliffe, A. F.

    2014-03-05

    Tokamak power plants are studied with advanced and conservative design philosophies in order to identify the impacts on the resulting designs and to provide guidance to critical research needs. Incorporating updated physics understanding, and using more sophisticated engineering and physics analysis, the tokamak configurations have developed a more credible basis compared to older studies. The advanced configuration assumes a self-cooled lead lithium (SCLL) blanket concept with SiC composite structural material with 58% thermal conversion efficiency. This plasma has a major radius of 6.25 m, a toroidal field of 6.0 T, a q95 of 4.5, a {beta}N{sup total} of 5.75, H{sub 98} of 1.65, n/nGr of 1.0, and peak divertor heat flux of 13.7 MW/m{sup 2}. The conservative configuration assumes a dual coolant lead lithium (DCLL) blanket concept with ferritic steel structural material and helium coolant, achieving a thermal conversion efficiency of 45%. The plasma major radius is 9.75 m, a toroidal field of 8.75 T, a q95 of 8.0, a {beta}N{sup total} of 2.5, H{sub 98} of 1.25, n/n{sub Gr} of 1.3, and peak divertor heat flux of 10 MW/m{sup 2}. The divertor heat flux treatment with a narrow power scrape-off width has driven the plasmas to larger major radius. Edge and divertor plasma simulations are targeting a basis for high radiated power fraction in the divertor, which is necessary for solutions to keep the peak heat flux in the range of 10-15 MW/m{sup 2}. Combinations of the advanced and conservative approaches show intermediate sizes. A new systems code using a database approach has been used and shows that the operating point is really an operating zone with some range of plasma and engineering parameters and very similar costs of electricity. Papers in this issue provide more detailed discussion of the work summarized here.

  9. Barriers to adequate prenatal care utilization in American Samoa

    PubMed Central

    Hawley, Nicola L; Brown, Carolyn; Nu’usolia, Ofeira; Ah-Ching, John; Muasau-Howard, Bethel; McGarvey, Stephen T

    2013-01-01

    Objective To describe the utilization of prenatal care in American Samoan women and to identify socio-demographic predictors of inadequate prenatal care utilization. Methods Using data from prenatal clinic records, women (n=692) were categorized according to the Adequacy of Prenatal Care Utilization Index as having received adequate plus, adequate, intermediate or inadequate prenatal care during their pregnancy. Categorical socio-demographic predictors of the timing of initiation of prenatal care (week of gestation) and the adequacy of received services were identified using one way Analysis of Variance (ANOVA) and independent samples t-tests. Results Between 2001 and 2008 85.4% of women received inadequate prenatal care. Parity (P=0.02), maternal unemployment (P=0.03), and both parents being unemployed (P=0.03) were negatively associated with the timing of prenatal care initation. Giving birth in 2007–2008, after a prenatal care incentive scheme had been introduced in the major hospital, was associated with earlier initiation of prenatal care (20.75 versus 25.12 weeks; P<0.01) and improved adequacy of received services (95.04% versus 83.8%; P=0.02). Conclusion The poor prenatal care utilization in American Samoa is a major concern. Improving healthcare accessibility will be key in encouraging women to attend prenatal care. The significant improvements in the adequacy of prenatal care seen in 2007–2008 suggest that the prenatal care incentive program implemented in 2006 may be a very positive step toward addressing issues of prenatal care utilization in this population. PMID:24045912

  10. A study of cathode erosion in high power arcjets

    NASA Astrophysics Data System (ADS)

    Harris, William Jackson, III

    Cathode erosion continues to be one of the predominant technology concerns for high power arcjets. This study will show that cathode erosion in these devices is significantly affected by several mitigating factors, including propellant composition, propellant flowrate, current level, cathode material, and power supply current ripple. In a series of 50-hour and 100-hour long duration experiments, using a water-cooled 30 kilowatt laboratory arcjet, variations in the steady-state cathode erosion rate were characterized for each of these factors using nitrogen propellant at a fixed arc current of 250 Amperes. A complementary series of measurements was made using hydrogen propellant at an arc current of 100 Amperes. The cold cathode erosion rate was also differentiated from the steady-state cathode erosion rate in a series of multi-start cathode erosion experiments. Results of these measurements are presented, along with an analysis of the significant effects of current ripple on arcjet cathode erosion. As part of this study, over a dozen refractory cathode materials were evaluated to measure their resistance to arcjet cathode erosion. Among the materials tested were W-ThO2(1%, 2%, 4%), poly and mono-crystalline W, W-LaB6, W-La2O3, W-BaO2, W-BaCaAl2O4, W-Y2O3, and ZrB2. Based on these measurements, several critical material properties were identified, such work function, density, porosity, melting point, and evaporation rate. While the majority of the materials failed to outperform traditional W-ThO2, these experimental results are used to develop a parametric model of the arcjet cathode physics. The results of this model, and the results of a finite-element thermal analysis of the arcjet cathode, are presented to better explain the relative performance of the materials tested.

  11. Feasibility Study of a Satellite Solar Power Station

    NASA Technical Reports Server (NTRS)

    Glaser, P. E.; Maynard, O. E.; Mackovciak, J. J. R.; Ralph, E. I.

    1974-01-01

    A feasibility study of a satellite solar power station (SSPS) was conducted to: (1) explore how an SSPS could be flown and controlled in orbit; (2) determine the techniques needed to avoid radio frequency interference (RFI); and (3) determine the key environmental, technological, and economic issues involved. Structural and dynamic analyses of the SSPS structure were performed, and deflections and internal member loads were determined. Desirable material characteristics were assessed and technology developments identified. Flight control performance of the SSPS baseline design was evaluated and parametric sizing studies were performed. The study of RFI avoidance techniques covered (1) optimization of the microwave transmission system; (2) device design and expected RFI; and (3) SSPS RFI effects. The identification of key issues involved (1) microwave generation, transmissions, and rectification and solar energy conversion; (2) environmental-ecological impact and biological effects; and (3) economic issues, i.e., costs and benefits associated with the SSPS. The feasibility of the SSPS based on the parameters of the study was established.

  12. Preliminary study of AC power feeders for AGS booster

    SciTech Connect

    Meth, M.

    1992-07-17

    It has been proposed that the AGS Heavy Ion/Proton Booster be excited directly from the electric power distribution system without intervening an energy storage buffer such as an MG set or a magnetic energy buffer. The average power requirement of the AGS Booster is less than many single-loads presently housed on the lab site. However, the power swing will be the largest single pulsating load on the lab site. The large power swings will impact on the power grid producing utility-line disturbances such as voltage fluctuations and harmonic generation. Thus, it is necessary to carefully evaluate the quality of the electric power system resulting from the interconnection, such that the utility system is not degraded either on the lab site or at LILCO's substation.

  13. Preliminary study of AC power feeders for AGS booster

    SciTech Connect

    Meth, M.

    1992-07-17

    It has been proposed that the AGS Heavy Ion/Proton Booster be excited directly from the electric power distribution system without intervening an energy storage buffer such as an MG set or a magnetic energy buffer. The average power requirement of the AGS Booster is less than many single-loads presently housed on the lab site. However, the power swing will be the largest single pulsating load on the lab site. The large power swings will impact on the power grid producing utility-line disturbances such as voltage fluctuations and harmonic generation. Thus, it is necessary to carefully evaluate the quality of the electric power system resulting from the interconnection, such that the utility system is not degraded either on the lab site or at LILCO`s substation.

  14. Solar power satellite system definition study, phase 2.

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A program plan for the Solar Power Satellite Program is presented. The plan includes research, development, and evaluation phase, engineering and development and cost verification phase, prototype construction, and commercialization. Cost estimates and task requirements are given for the following technology areas: (1) solar arrays; (2) thermal engines and thermal systems; (3) power transmission (to earth); (4) large space structures; (5) materials technology; (6) system control; (7) space construction; (8) space transportation; (9) power distribution, and space environment effects.

  15. EMU battery/SMM power tool characterization study

    NASA Technical Reports Server (NTRS)

    Palandati, C.

    1982-01-01

    The power tool which will be used to replace the attitude control system in the SMM spacecraft was modified to operate from a self contained battery. The extravehicular mobility unit (EMU) battery was tested for the power tool application. The results are that the EMU battery is capable of operating the power tool within the pulse current range of 2.0 to 15.0 amperes and battery temperature range of -10 to 40 degrees Celsius.

  16. Role of inhalation studies with animals in defining human health risks for vehicle and power plant emissions.

    PubMed Central

    McClellan, R O

    1983-01-01

    Automotive vehicles and power plants using fossil fuels emit a complex array of gases and particulate material. The physical and chemical characteristics of these emissions vary markedly between sources and comprise only a portion of the contributors to air pollution exposure of people. Further, it is well recognized that a single form of self-inflicted air pollution, cigarette smoking, is the dominant cause of air pollution-induced disease. These factors minimize our potential for developing an adequate understanding of the health effects of vehicle and power plant emissions by studying only people. The alternative is to use the human data to the extent feasible and complement it with information gained in studies with macromolecules, organelles, cells, tissues and whole animals. Within this context, this paper reviews the use of inhalation studies with animals for defining human health risks of airborne materials, especially particulate materials. The major areas covered are: the fate of inhaled materials, the pathogenesis of disease induced by inhaled materials and long-term animal studies to identify late-occurring effects. Emphasis is placed on the utility of studies in whole animals as integrative models in which the multiple processes such as xenobiotic metabolism, cell injury, repair, transformation and promotion under the influence of many host factors interact in a manner that may not be directly observed in isolated cells or tissues. PMID:6186479

  17. Study on load forecasting to data centers of high power density based on power usage effectiveness

    NASA Astrophysics Data System (ADS)

    Zhou, C. C.; Zhang, F.; Yuan, Z.; Zhou, L. M.; Wang, F. M.; Li, W.; Yang, J. H.

    2016-08-01

    There is usually considerable energy consumption in data centers. Load forecasting to data centers is in favor of formulating regional load density indexes and of great benefit to getting regional spatial load forecasting more accurately. The building structure and the other influential factors, i.e. equipment, geographic and climatic conditions, are considered for the data centers, and a method to forecast the load of the data centers based on power usage effectiveness is proposed. The cooling capacity of a data center and the index of the power usage effectiveness are used to forecast the power load of the data center in the method. The cooling capacity is obtained by calculating the heat load of the data center. The index is estimated using the group decision-making method of mixed language information. An example is given to prove the applicability and accuracy of this method.

  18. Experimental studies of the stopping powers of various types of matter for protons and helium ions

    SciTech Connect

    Potetyunko, G.N.

    1986-03-01

    The experimental studies of the stopping powers of various types of matter for protons and helium ions are reviewed. The experimental methods of determining the stopping power are analyzed and the ranges where they are applicable are discussed. A comparison is made with the experimental data cited in the most commonly used tables of stopping powers. Empirical formulas for the stopping power and the rule of additivity of the stopping powers of multicomponent matter are discussed.

  19. Nuclear space power safety and facility guidelines study

    SciTech Connect

    Mehlman, W.F.

    1995-09-11

    This report addresses safety guidelines for space nuclear reactor power missions and was prepared by The Johns Hopkins University Applied Physics Laboratory (JHU/APL) under a Department of Energy grant, DE-FG01-94NE32180 dated 27 September 1994. This grant was based on a proposal submitted by the JHU/APL in response to an {open_quotes}Invitation for Proposals Designed to Support Federal Agencies and Commercial Interests in Meeting Special Power and Propulsion Needs for Future Space Missions{close_quotes}. The United States has not launched a nuclear reactor since SNAP 10A in April 1965 although many Radioisotope Thermoelectric Generators (RTGs) have been launched. An RTG powered system is planned for launch as part of the Cassini mission to Saturn in 1997. Recently the Ballistic Missile Defense Office (BMDO) sponsored the Nuclear Electric Propulsion Space Test Program (NEPSTP) which was to demonstrate and evaluate the Russian-built TOPAZ II nuclear reactor as a power source in space. As of late 1993 the flight portion of this program was canceled but work to investigate the attributes of the reactor were continued but at a reduced level. While the future of space nuclear power systems is uncertain there are potential space missions which would require space nuclear power systems. The differences between space nuclear power systems and RTG devices are sufficient that safety and facility requirements warrant a review in the context of the unique features of a space nuclear reactor power system.

  20. DEVELOPMENT OF HIGH-POWER BROADBAND TUBES AND RELATED STUDIES

    DTIC Science & Technology

    Performance characteristics of a centipede high-power TWT are presented. The design of components for the 10 Mw cloverleaf TWT is described and a...be made relatively easily and cheaply. Performance characteristics of a centipede high-power TWT are presented. The design of components for the 10

  1. Performance study of a hydrogen powered metal hydride actuator

    NASA Astrophysics Data System (ADS)

    Mainul Hossain Bhuiya, Md; Kim, Kwang J.

    2016-04-01

    A thermally driven hydrogen powered actuator integrating metal hydride hydrogen storage reactor, which is compact, noiseless, and able to generate smooth actuation, is presented in this article. To test the plausibility of a thermally driven actuator, a conventional piston type actuator was integrated with LaNi5 based hydrogen storage system. Copper encapsulation followed by compaction of particles into pellets, were adopted to improve overall thermal conductivity of the reactor. The operation of the actuator was thoroughly investigated for an array of operating temperature ranges. Temperature swing of the hydride reactor triggering smooth and noiseless actuation over several operating temperature ranges were monitored for quantification of actuator efficiency. Overall, the actuator generated smooth and consistent strokes during repeated cycles of operation. The efficiency of the actuator was found to be as high as 13.36% for operating a temperature range of 20 °C-50 °C. Stress-strain characteristics, actuation hysteresis etc were studied experimentally. Comparison of stress-strain characteristics of the proposed actuator with traditional actuators, artificial muscles and so on was made. The study suggests that design modification and use of high pressure hydride may enhance the performance and broaden the application horizon of the proposed actuator in future.

  2. Adequate Yearly Progress (AYP) at Your Library Media Center

    ERIC Educational Resources Information Center

    Anderson, Cynthia

    2007-01-01

    Together administration and the library media center form a team that can make a difference in student learning and, in turn, in student achievement. The library media center can contribute to improve student learning, and there is an amazingly small cost that administration must pay for this powerful support. This article addresses…

  3. Tissue type characterization using photoacoustic power spectrum, a feasibility study

    NASA Astrophysics Data System (ADS)

    Tavakoli, Behnoosh; Goldstein, Seth D.; Kang, Jin U.; Choti, Michaal; Boctor, Emad M.

    2015-03-01

    The development of technologies capable of non-invasive characterization of tissue has the potential to significantly improve diagnostic and therapeutic medical interventions. In this study we investigated the feasibility of a noninvasive photoacoustic (PA) approach for characterizing biological tissues. The measurement was performed in the transmission mode with a wideband hydrophone while a tunable Q-switched Nd:YAG pulsed laser was used for illumination. The power spectrum of photoacoustic signal induced by a pulsed laser light from tissue was analyzed and features were extracted to study their correlation with tissue biomechanical properties. For a controlled study, tissue mimicking gelatin phantoms with different densities and equivalent optical absorptions were used as targets. The correlation between gelatin concentration of such phantoms and their mechanical properties were validated independently with a dynamic mechanical analyzer capable of calculating complex loss and storage moduli between two compression plates. It was shown that PA spectrums were shifted towards higher frequencies by increasing gelatin concentration. In order to quantify this effect, signal energy in two intervals of low and high frequency ranges were calculated. Gelatin concentration was correlated with PA energy in high frequency range with R2=0.94. Subsequently, PA signals generated from freshly resected human thyroid specimens were measured and analyzed in a similar fashion. We found that in aggregate, malignant thyroid tissue contains approximately 1.6 times lower energy in the high frequency range in comparison to normal thyroid tissue (p<0.01). This ratio increased with increasing illumination wavelength from 700 nm to 900nm. In summary, this study demonstrated the feasibility of using photoacoustic technique for characterizing tissue on the basis of viscoelastic properties of the tissue.

  4. Biologically based epidemiological studies of electric power and cancer

    SciTech Connect

    Stevens, R.G.

    1993-12-01

    Use of electricity is a hallmark of the industrialization process, but there has been no suspicion that electricity could increase the risk of cancer. Recently, however, a number of epidemiologic studies have suggested that electromagnetic fields (EMF) may do just that. Although few cancer experiments have been done yet, there are a number of biological effects of EMF reported in the literature that might provide bases for designing cancer experiments and epidemiologic studies. These include effects of EMF on: (a) DNA transcription and translation, (b) calcium balance in cells, and (c) pineal production of melatonin. Alterations in DNA transcription and translation could have pleiotropic effects. Disruption of calcium homeostasis has many implications including oncogene activation, promotional activity via protein kinases and ornithine decarboxylase (ODC), and increasing oxidative stress. Reduction of melatonin suggests a possible increased risk of cancers of hormone-dependent tissues such as breast and prostate. The idea that a cancer-causing agent must either be an initiator or a promoter should be discarded; indeed, the phenomenologic meaning of these two terms has become confused with imputed mechanistic necessity in recent years. Agents that affect division of normal cells or of fully transformed cells can play an important role in clinical cancer development quite apart from initiation or promotion. Epidemiologic studies of EMF and cancer should attempt to take account of other products of electric power (e.g., light at night) or factors associated with occupational EMF exposure (e.g., toxic chemicals) that may increase cancer risk and therefore act as cofactors or confounders. Epidemiology and laboratory studies should act synergistically in determining if there is a problem and identifying mitigation strategies if needed. 84 refs., 3 figs., 1 tab.

  5. Systemic Crisis of Civilization: In Search for Adequate Solution

    NASA Astrophysics Data System (ADS)

    Khozin, Grigori

    In December 1972 a jumbo jet crashed in the Florida Everglades with the loss of 101 lives. The pilot, distracted by a minor malfunction, failed to note until too late the warning signal that - correctly - indicated an impending disaster. His sudden, astonished cry of Hey, what happening here? were his last words 1. Three decades after this tragic episode, as the Humankind approaches the threshold of the third Millennium, the problem of adequate reaction to warning signals of different nature and of distinguishing minor malfunctions in everyday life of society, in economy and technology as well as in evolution of biosphere from grave threats to the world community and the phenomenon of life on our planet remains crucial to human survival and the future of Civilization. Rational use of knowledge and technology available to the world community remains in this context the corner stone of discussions on the destiny of the intelligent life both on the planet Earth and in the Universe (the fact of intelligent life in the Universe is to be detected by the Humankind)…

  6. ENSURING ADEQUATE SAFETY WHEN USING HYDROGEN AS A FUEL

    SciTech Connect

    Coutts, D

    2007-01-22

    Demonstration projects using hydrogen as a fuel are becoming very common. Often these projects rely on project-specific risk evaluations to support project safety decisions. This is necessary because regulations, codes, and standards (hereafter referred to as standards) are just being developed. This paper will review some of the approaches being used in these evolving standards, and techniques which demonstration projects can implement to bridge the gap between current requirements and stakeholder desires. Many of the evolving standards for hydrogen-fuel use performance-based language, which establishes minimum performance and safety objectives, as compared with prescriptive-based language that prescribes specific design solutions. This is being done for several reasons including: (1) concern that establishing specific design solutions too early will stifle invention, (2) sparse performance data necessary to support selection of design approaches, and (3) a risk-adverse public which is unwilling to accept losses that were incurred in developing previous prescriptive design standards. The evolving standards often contain words such as: ''The manufacturer shall implement the measures and provide the information necessary to minimize the risk of endangering a person's safety or health''. This typically implies that the manufacturer or project manager must produce and document an acceptable level of risk. If accomplished using comprehensive and systematic process the demonstration project risk assessment can ease the transition to widespread commercialization. An approach to adequately evaluate and document the safety risk will be presented.

  7. Dose Limits for Man do not Adequately Protect the Ecosystem

    SciTech Connect

    Higley, Kathryn A.; Alexakhin, Rudolf M.; McDonald, Joseph C.

    2004-08-01

    It has been known for quite some time that different organisms display differing degrees of sensitivity to the effects of ionizing radiations. Some microorganisms such as the bacterium Micrococcus radiodurans, along with many species of invertebrates, are extremely radio-resistant. Humans might be categorized as being relatively sensitive to radiation, and are a bit more resistant than some pine trees. Therefore, it could be argued that maintaining the dose limits necessary to protect humans will also result in the protection of most other species of flora and fauna. This concept is usually referred to as the anthropocentric approach. In other words, if man is protected then the environment is also adequately protected. The ecocentric approach might be stated as; the health of humans is effectively protected only when the environment is not unduly exposed to radiation. The ICRP is working on new recommendations dealing with the protection of the environment, and this debate should help to highlight a number of relevant issues concerning that topic.

  8. The neutronics studies of fusion fission hybrid power reactor

    SciTech Connect

    Zheng Youqi; Wu Hongchun; Zu Tiejun; Yang Chao; Cao Liangzhi

    2012-06-19

    In this paper, a series of neutronics analysis of hybrid power reactor is proposed. The ideas of loading different fuels in a modular-type fission blanket is analyzed, fitting different level of fusion developments, i.e., the current experimental power output, the level can be obtained in the coming future and the high-power fusion reactor like ITER. The energy multiplication of fission blankets and tritium breeding ratio are evaluated as the criterion of design. The analysis is implemented based on the D-type simplified model, aiming to find a feasible 1000MWe hybrid power reactor for 5 years' lifetime. Three patterns are analyzed: 1) for the low fusion power, the reprocessed fuel is chosen. The fuel with high plutonium content is loaded to achieve large energy multiplication. 2) For the middle fusion power, the spent fuel from PWRs can be used to realize about 30 times energy multiplication. 3) For the high fusion power, the natural uranium can be directly used and about 10 times energy multiplication can be achieved.

  9. Anaerobic Digestion and Combined Heat and Power Study

    SciTech Connect

    Frank J. Hartz Rob Taylor Grant Davies

    2011-12-30

    One of the underlying objectives of this study is to recover the untapped energy in wastewater biomass. Some national statistics worth considering include: (1) 5% of the electrical energy demand in the US is used to treat municipal wastewater; (2) This carbon rich wastewater is an untapped energy resource; (3) Only 10% of wastewater treatment plants (>5mgd) recover energy; (4) Wastewater treatment plants have the potential to produce > 575 MW of energy nationwide; and (5) Wastewater treatment plants have the potential to capture an additional 175 MW of energy from waste Fats, Oils and Grease. The WSSC conducted this study to determine the feasibility of utilizing anaerobic digestion and combined heat and power (AD/CHP) and/or biosolids gasification and drying facilities to produce and utilize renewable digester biogas. Digester gas is considered a renewable energy source and can be used in place of fossil fuels to reduce greenhouse gas emissions. The project focus includes: (1) Converting wastewater Biomass to Electricity; (2) Using innovative technologies to Maximize Energy Recovery; and (3) Enhancing the Environment by reducing nutrient load to waterways (Chesapeake Bay), Sanitary Sewer Overflows (by reducing FOG in sewers) and Greenhouse Gas Emissions. The study consisted of these four tasks: (1) Technology screening and alternative shortlisting, answering the question 'what are the most viable and cost effective technical approaches by which to recover and reuse energy from biosolids while reducing disposal volume?'; (2) Energy recovery and disposal reduction potential verification, answering the question 'how much energy can be recovered from biosolids?'; (3) Economic environmental and community benefit analysis, answering the question 'what are the potential economic, environmental and community benefits/impacts of each approach?'; and (4) Recommend the best plan and develop a concept design.

  10. Megawatt Space Power Conditioning, Distribution, and Control Study

    DTIC Science & Technology

    1988-03-01

    2.4.1 Reactor Transmision Interface 16 2.4.2 Transmission Converter Interface 16 2.4.3 Klystrode Accelerator Interface 16 2.5 Summary and Development...iii CONTENTS (Continued) Page 3.2 Power Sources 43 3.2.1 Prime Power 43 3.2.2 Rotating Machines 47 3.2.2.1 Alternators 47 3.2.3 Static Power...they can be categorized as follows: 2.2.1 Alternating Current (ac) Devices. These are all turbine- generator machines , which can be driven by any

  11. System Study: Emergency Power System 1998–2013

    SciTech Connect

    Schroeder, John Alton

    2015-02-01

    This report presents an unreliability evaluation of the emergency power system (EPS) at 104 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2013 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10-year period, while yearly estimates for system unreliability are provided for the entire active period. No statistically significant trends were identified in the EPS results.

  12. System Study: Emergency Power System 1998-2014

    SciTech Connect

    Schroeder, John Alton

    2015-12-01

    This report presents an unreliability evaluation of the emergency power system (EPS) at 104 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. An extremely statistically significant increasing trend was observed for EPS system unreliability for an 8-hour mission. A statistically significant increasing trend was observed for EPS system start-only unreliability.

  13. NASA Fuel Tank Wireless Power and Signal Study

    NASA Technical Reports Server (NTRS)

    Merrill, Garrick

    2015-01-01

    Hydro Technologies has developed a custom electronics and mechanical framework for interfacing with off-the-shelf sensors to achieve through barrier sensing solutions. The core project technology relies on Hydro Technologies Wireless Power and Signal Interface (Wi psi) System for transmitting data and power wirelessly using magnetic fields. To accomplish this, Wi psi uses a multi-frequency local magnetic field to produce magnetic fields capable of carrying data and power through almost any material such as metals, seawater, concrete, and air. It will also work through layers of multiple materials.

  14. Solar-Powered Desalination: A Modelling and Experimental Study

    NASA Astrophysics Data System (ADS)

    Leblanc, Jimmy; Andrews, John

    2007-10-01

    Water shortage is becoming one of the major problems worldwide. As such, desalination technologies have been implemented to meet growing demands for fresh water. Among the desalination technologies, thermal desalination, including multi stage flash (MSF) and multi effect evaporation (MEE), is the current leading desalination process. Reverse osmosis (RO) is also being increasingly used. Despite technological improvements, thermal desalination and reverse osmosis continue to be intensive fossil-fuel consumers and contribute to increased levels of greenhouse gases. As energy costs rise, thermal desalination by solar energy and/or low cost waste heat is likely to become increasingly attractive. As part of a project investigating the productive use of saline land and the development of sustainable desalination systems, the feasibility of producing potable water from seawater or brackish water using desalination systems powered by renewable energy in the form of low-temperature solar-thermal sources has been studied. A salinity-gradient solar pond and an evacuated tube solar collector system have been used as heat sources. Solar ponds combine solar energy collection with long-term storage and can provide reliable thermal energy at temperature ranges from 50 to 90 °C. A visual basic computer model of the different multi-stage flash desalination processes coupled with a salinity-gradient solar pond was developed to determine which process is preferable in regards to performance and greenhouse impact. The governing mathematical equations are derived from mass balances, heat energy balances, and heat transfer characteristics. Using the results from the modelling, a small-scale solar-powered desalination system, capable of producing up to 500 litres of fresh water per day, was designed and manufactured. This single-stage flash system consists of two main units: the heat supply and storage system and the flash desalination unit. Two different condenser heat exchanger

  15. Feasibility Study of Hydrogen Production at Existing Nuclear Power Plants

    SciTech Connect

    Stephen Schey

    2009-07-01

    Cooperative Agreement DE-FC07-06ID14788 was executed between the U.S. Department of Energy, Electric Transportation Applications, and Idaho National Laboratory to investigate the economics of producing hydrogen by electrolysis using electricity generated by nuclear power. The work under this agreement is divided into the following four tasks: Task 1 – Produce Data and Analyses Task 2 – Economic Analysis of Large-Scale Alkaline Electrolysis Task 3 – Commercial-Scale Hydrogen Production Task 4 – Disseminate Data and Analyses. Reports exist on the prospect that utility companies may benefit from having the option to produce electricity or produce hydrogen, depending on market conditions for both. This study advances that discussion in the affirmative by providing data and suggesting further areas of study. While some reports have identified issues related to licensing hydrogen plants with nuclear plants, this study provides more specifics and could be a resource guide for further study and clarifications. At the same time, this report identifies other area of risks and uncertainties associated with hydrogen production on this scale. Suggestions for further study in some of these topics, including water availability, are included in the report. The goals and objectives of the original project description have been met. Lack of industry design for proton exchange membrane electrolysis hydrogen production facilities of this magnitude was a roadblock for a significant period. However, recent design breakthroughs have made costing this facility much more accurate. In fact, the new design information on proton exchange membrane electrolyzers scaled to the 1 kg of hydrogen per second electrolyzer reduced the model costs from $500 to $100 million. Task 1 was delayed when the original electrolyzer failed at the end of its economic life. However, additional valuable information was obtained when the new electrolyzer was installed. Products developed during this study

  16. The concept of adequate causation and Max Weber's comparative sociology of religion.

    PubMed

    Buss, A

    1999-06-01

    Max Weber's The Protestant Ethic and the Spirit of Capitalism, studied in isolation, shows mainly an elective affinity or an adequacy on the level of meaning between the Protestant ethic and the 'spirit' of capitalism. Here it is suggested that Weber's subsequent essays on 'The Economic Ethics of World Religions' are the result of his opinion that adequacy on the level of meaning needs and can be verified by causal adequacy. After some introductory remarks, particularly on elective affinity, the paper tries to develop the concept of adequate causation and the related concept of objective possibility on the basis of the work of v. Kries on whom Weber heavily relied. In the second part, this concept is used to show how the study of the economic ethics of India, China, Rome and orthodox Russia can support the thesis that the 'spirit' of capitalism, although it may not have been caused by the Protestant ethic, was perhaps adequately caused by it.

  17. Basic Studies on Chaotic Characteristics of Electric Power Market Price

    NASA Astrophysics Data System (ADS)

    Takeuchi, Yuya; Miyauchi, Hajime; Kita, Toshihiro

    Recently, deregulation and reform of electric power utilities have been progressing in many parts of the world. In Japan, partial deregulation has been started from generation sector since 1995 and partial deregulation of retail sector is executed through twice law revisions. Through the deregulation, because electric power is traded in the market and its price is always fluctuated, it is important for the electric power business to analyze and predict the price. Although the price data of the electric power market is time series data, it is not always proper to analyze by the linear model such as ARMA because the price sometimes changes suddenly. Therefore, in this paper, we apply the methods of chaotic time series analysis, one of non-linear analysis methods, and investigate the chaotic characteristics of the system price of JEPX.

  18. A comparative study of electric power distribution systems for spacecraft

    NASA Technical Reports Server (NTRS)

    Stuart, Thomas A.; King, Roger J.

    1990-01-01

    The electric power distribution systems for spacecraft are compared concentrating on two interrelated issues: the choice between dc and high frequency ac, and the converter/inverter topology to be used at the power source. The relative merits of dc and ac distribution are discussed. Specific converter and inverter topologies are identified and analyzed in detail for the purpose of detailed comparison. Finally, specific topologies are recommended for use in dc and ac systems.

  19. Engine Power Turbine and Propulsion Pod Arrangement Study

    NASA Technical Reports Server (NTRS)

    Robuck, Mark; Zhang, Yiyi

    2014-01-01

    A study has been conducted for NASA Glenn Research Center under contract NNC10BA05B, Task NNC11TA80T to identify beneficial arrangements of the turboshaft engine, transmissions and related systems within the propulsion pod nacelle of NASA's Large Civil Tilt-Rotor 2nd iteration (LCTR2) vehicle. Propulsion pod layouts were used to investigate potential advantages, disadvantages, as well as constraints of various arrangements assuming front or aft shafted engines. Results from previous NASA LCTR2 propulsion system studies and tasks performed by Boeing under NASA contracts are used as the basis for this study. This configuration consists of two Fixed Geometry Variable Speed Power Turbine Engines and related drive and rotor systems (per nacelle) arranged in tilting nacelles near the wing tip. Entry-into-service (EIS) 2035 technology is assumed for both the engine and drive systems. The variable speed rotor system changes from 100 percent speed for hover to 54 percent speed for cruise by the means of a two speed gearbox concept developed under previous NASA contracts. Propulsion and drive system configurations that resulted in minimum vehicle gross weight were identified in previous work and used here. Results reported in this study illustrate that a forward shafted engine has a slight weight benefit over an aft shafted engine for the LCTR2 vehicle. Although the aft shafted engines provide a more controlled and centered CG (between hover and cruise), the length of the long rotor shaft and complicated engine exhaust arrangement outweighed the potential benefits. A Multi-Disciplinary Analysis and Optimization (MDAO) approach for transmission sizing was also explored for this study. This tool offers quick analysis of gear loads, bearing lives, efficiencies, etc., through use of commercially available RomaxDESIGNER software. The goal was to create quick methods to explore various concept models. The output results from RomaxDESIGNER have been successfully linked to Boeing

  20. A Feasibility Study of Solar Thermal Power Generation as the Pumping Power Source for Pumped Storage in Indonesia

    NASA Astrophysics Data System (ADS)

    Funatsu, Tetsuya; Natsume, Hiroaki

    A pumped storage hydroelectric generation (PSHG) has been studied as alternative peak power source of the oil-fired power generation in Indonesia. However, because there is no surplus base load electricity even in the night, the economic advantage can not be found. The possibility of solar thermal power generation (STPG) is investigated to restrain the increase of fuel consumption by the existing peak power source. The optimum system simulation and the analysis of economy and environmental impact by a multiobjective optimization method provide the following results. The optimum aperture area and thermal storage capacity of STPG are found by the simulation based on the climate and the solar condition in West Java. PSHG with STPG as the power source of storage pump shows lower generation cost and CO2 emission than PSHG with existing oil fired peak power sources. Even if the fuel switch from oil to gas is supposed in future, PSHG with STPG will achieve the lower generation cost and CO2 emission than PSHG with the oil/gas fired combined cycle by sharing the peak electricity supply with the oil/gas fired combined cycle in an appropriate ratio. Furthermore, if the crude oil price hike in future is considered, PSHG with STPG may be the optimal solution for the peak electricity supply of Java-Bari grid.

  1. Rotating Detonation Combustion: A Computational Study for Stationary Power Generation

    NASA Astrophysics Data System (ADS)

    Escobar, Sergio

    The increased availability of gaseous fossil fuels in The US has led to the substantial growth of stationary Gas Turbine (GT) usage for electrical power generation. In fact, from 2013 to 2104, out of the 11 Tera Watts-hour per day produced from fossil fuels, approximately 27% was generated through the combustion of natural gas in stationary GT. The thermodynamic efficiency for simple-cycle GT has increased from 20% to 40% during the last six decades, mainly due to research and development in the fields of combustion science, material science and machine design. However, additional improvements have become more costly and more difficult to obtain as technology is further refined. An alternative to improve GT thermal efficiency is the implementation of a combustion regime leading to pressure-gain; rather than pressure loss across the combustor. One concept being considered for such purpose is Rotating Detonation Combustion (RDC). RDC refers to a combustion regime in which a detonation wave propagates continuously in the azimuthal direction of a cylindrical annular chamber. In RDC, the fuel and oxidizer, injected from separated streams, are mixed near the injection plane and are then consumed by the detonation front traveling inside the annular gap of the combustion chamber. The detonation products then expand in the azimuthal and axial direction away from the detonation front and exit through the combustion chamber outlet. In the present study Computational Fluid Dynamics (CFD) is used to predict the performance of Rotating Detonation Combustion (RDC) at operating conditions relevant to GT applications. As part of this study, a modeling strategy for RDC simulations was developed. The validation of the model was performed using benchmark cases with different levels of complexity. First, 2D simulations of non-reactive shock tube and detonation tubes were performed. The numerical predictions that were obtained using different modeling parameters were compared with

  2. Research on stochastic power-flow study methods. Final report

    SciTech Connect

    Heydt, G. T.

    1981-01-01

    A general algorithm to determine the effects of uncertainty in bus load and generation on the output of conventional power flow analysis is presented. The use of statistical moments is presented and developed as a means for representing the stochastic process. Statistical moments are used to describe the uncertainties, and facilitate the calculations of single and multivarlate probability density functions of input and output variables. The transformation of the uncertainty through the power flow equations is made by the expansion of the node equations in a multivariate Taylor series about an expected operating point. The series is truncated after the second order terms. Since the power flow equations are nonlinear, the expected values of output quantities is in general not the solution to the conventional load flow problem using expected values of input quantities. The second order transformation offers a correction vector and allows the consideration of larger uncertainties which have caused significant error in the current linear transformation algorithms. Voltage controlled busses are included with consideration of upper and lower limits. The finite reactive power available at generation sites, and fixed ranges of transformer tap movement may have a significant effect on voltage and line power flow statistics. A method is given which considers limitation constraints in the evaluation of all output quantities. The bus voltages, line power flows, transformer taps, and generator reactive power requirements are described by their statistical moments. Their values are expressed in terms of the probability that they are above or below specified limits, and their expected values given that they do fall outside the limits. Thus the algorithm supplies information about severity of overload as well as probability of occurrence. An example is given for an eleven bus system, evaluating each quantity separately. The results are compared with Monte Carlo simulation.

  3. Overview study of Space Power Technologies for the advanced energetics program. [spacecraft

    NASA Technical Reports Server (NTRS)

    Taussig, R.; Gross, S.; Millner, A.; Neugebauer, M.; Phillips, W.; Powell, J.; Schmidt, E.; Wolf, M.; Woodcock, G.

    1981-01-01

    Space power technologies are reviewed to determine the state-of-the-art and to identify advanced or novel concepts which promise large increases in performance. The potential for incresed performance is judged relative to benchmarks based on technologies which have been flight tested. Space power technology concepts selected for their potentially high performance are prioritized in a list of R & D topical recommendations for the NASA program on Advanced Energetics. The technology categories studied are solar collection, nuclear power sources, energy conversion, energy storage, power transmission, and power processing. The emphasis is on electric power generation in space for satellite on board electric power, for electric propulsion, or for beamed power to spacecraft. Generic mission categories such as low Earth orbit missions and geosynchronous orbit missions are used to distinguish general requirements placed on the performance of power conversion technology. Each space power technology is judged on its own merits without reference to specific missions or power systems. Recommendations include 31 space power concepts which span the entire collection of technology categories studied and represent the critical technologies needed for higher power, lighter weight, more efficient power conversion in space.

  4. HYLIFE-II power conversion system design and cost study

    SciTech Connect

    Hoffman, M.A. . Dept. of Mechanical, Aeronautical and Materials Engineering)

    1990-09-01

    The power conversion system for the HYLIFE-2 fusion power plant has been defined to include the IHX's (intermediate heat exchangers) and everything that support the exchange of energy from the reactor. It is referred to simply as the BOP (balance of plant) in the rest of this report. The above is a convenient division between the reactor equipment and the rest of the fusion power plant since the BOP design and cost then depend only on the specification of the thermal power to the IHX's and the temperature of the primary Flibe coolant into and out of the IHX's, and is almost independent of the details of the reactor design. The main efforts during the first year have been on the definition and thermal-hydraulics of the IHX's, the steam generators and the steam power plant, leading to the definition of a reference BOP with the molten salt, Flibe, as the primary coolant. A summary of the key results in each of these areas is given in this report.

  5. Compilation of Trade Studies for the Constellation Program Extravehicular Activity Spacesuit Power System

    NASA Technical Reports Server (NTRS)

    Fincannon, James

    2009-01-01

    This compilation of trade studies performed from 2005 to 2006 addressed a number of power system design issues for the Constellation Program Extravehicular Activity Spacesuit. Spacesuits were required for spacewalks and in-space activities as well as lunar and Mars surface operations. The trades documented here considered whether solar power was feasible for spacesuits, whether spacesuit power generation should be a distributed or a centralized function, whether self-powered in-space spacesuits were better than umbilically powered ones, and whether the suit power system should be recharged in place or replaced.

  6. Figure of merit studies of beam power concepts for advanced space exploration

    NASA Technical Reports Server (NTRS)

    Miller, Gabriel; Kadiramangalam, Murali N.

    1990-01-01

    Surface to surface, millimeter wavelength beam power systems for power transmission on the lunar base were investigated. Qualitative/quantitative analyses and technology assessment of 35, 110 and 140 GHz beam power systems were conducted. System characteristics including mass, stowage volume, cost and efficiency as a function of range and power level were calculated. A simple figure of merit analysis indicates that the 35 GHz system would be the preferred choice for lunar base applications, followed closely by the 110 GHz system. System parameters of a 35 GHz beam power system appropriate for power transmission on a recent lunar base concept studied by NASA-Johnson and the necessary deployment sequence are suggested.

  7. Roadway-powered-electric-vehicle impact study: preliminary supporting analyses

    SciTech Connect

    Latorre, V.R.; Spogen, L.R. Jr.

    1981-12-15

    The Roadway-Powered Electric Vehicle (RPEV) impact analysis program is described, and the results to date are presented. Expressions for the number of RPEVs and miles of powered roadways required to accomplish the desired replacement VMT in a USA have been derived, as well as a procedure to determine hourly energy demand resulting from using RPEVs and powered roadways. Conversions factors from VMT to electric energy have also been determined. The input and output data requirements for RECAPS have been determined, as well as the formats for the data for both the EPRI-supported effort, and the simpler, non-EPRI-supported program. The differences between the two programs are also discussed, and data are presented on the average VMT in each major utility service area within the US.

  8. A numerical study of scaling issues for trench power MOSFETs

    NASA Astrophysics Data System (ADS)

    Roig, J.; Cortés, I.; Jiménez, D.; Flores, D.; Iñiguez, B.; Hidalgo, S.; Rebollo, J.

    2005-06-01

    The effect of the scaling down on the electrical performance of trench power MOSFET structures is investigated in this work by means of numerical simulation tools. Layout dimensions of trench power MOSFETs have been continuously reduced in order to decrease the specific on-resistance, maintaining equal vertical dimensions. Nowadays, the last scaling efforts provide trench width and distance between two consecutive trenches in the submicron range. The resultant short distance between gates is expected to induce significant modifications in the device electrical performances, since the fully depletion condition will be feasible in the body region. Hence, the influence of the fully depleted body on the on-state resistance, threshold voltage, breakdown voltage, parasitic bipolar transistor and internal capacitances are features of particular interest. Furthermore, device reliability aspects, such as hot-carrier and self-heating effects, are evaluated by numerical simulation in trench power MOSFETs for the first time.

  9. A Study on Optimal Operation of Power Generation by Waste

    NASA Astrophysics Data System (ADS)

    Sugahara, Hideo; Aoyagi, Yoshihiro; Kato, Masakazu

    This paper proposes the optimal operation of power generation by waste. Refuse is taken as a new energy resource of biomass. Although some fossil fuel origin refuse like plastic may be mixed in, CO2 emission is not counted up except for above fossil fuel origin refuse for the Kyoto Protocol. Incineration is indispensable for refuse disposal and power generation by waste is environment-friendly and power system-friendly using synchronous generators. Optimal planning is a key point to make much of this merit. The optimal plan includes refuse incinerator operation plan with refuse collection and maintenance scheduling of refuse incinerator plant. In this paper, it has been made clear that the former plan increases generation energy through numerical simulations. Concerning the latter plan, a method to determine the maintenance schedule using genetic algorithm has been established. In addition, taking environmental load of CO2 emission into account, this is expected larger merits from environment and energy resource points of view.

  10. Free-space microwave power transmission study, phase 3

    NASA Technical Reports Server (NTRS)

    Brown, W. C.

    1975-01-01

    The results of an investigation of the technology of free-space power transmission by microwave beam are presented. A description of the steps that were taken to increase the overall dc to dc efficiency of microwave power transmission from 15 percent to over 50 percent is given. Included in this overall efficiency were the efficiencies of the dc to microwave conversion, the microwave transmission itself, and the microwave to dc conversion. Improvements in launching the microwave beam with high efficiency by means of a dual mode horn resulted in 95 percent of the output of the microwave generator reaching the receiving area. Emphasis was placed upon successive improvements in reception and rectification of the microwave power, resulting in the design of a rectenna device for this purpose whose efficiency was 75 percent. The procedures and the hardware developed were the basis for tests certified by the Jet Propulsion Laboratory in which an overall dc to dc efficiency of 54 percent was achieved.

  11. Study of reactor Brayton power systems for nuclear electric spacecraft

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The feasibility of using Brayton power systems for nuclear electric spacecraft was investigated. The primary performance parameters of systems mass and radiator area were determined for systems from 100 to 1000 kW sub e. Mathematical models of all system components were used to determine masses and volumes. Two completely independent systems provide propulsion power so that no single-point failure can jeopardize a mission. The waste heat radiators utilize armored heat pipes to limit meteorite puncture. The armor thickness was statistically determined to achieve the required probability of survival. A 400 kW sub e reference system received primary attention as required by the contract. The components of this system were defined and a conceptual layout was developed with encouraging results. An arrangement with redundant Brayton power systems having a 1500 K (2240 F) turbine inlet temperature was shown to be compatible with the dimensions of the space shuttle orbiter payload bay.

  12. Crew emergency return vehicle - Electrical power system design study

    NASA Technical Reports Server (NTRS)

    Darcy, E. C.; Barrera, T. P.

    1989-01-01

    A crew emergency return vehicle (CERV) is proposed to perform the lifeboat function for the manned Space Station Freedom. This escape module will be permanently docked to Freedom and, on demand, will be capable of safely returning the crew to earth. The unique requirements that the CERV imposes on its power source are presented, power source options are examined, and a baseline system is selected. It consists of an active Li-BCX DD-cell modular battery system and was chosen for the maturity of its man-rated design and its low development costs.

  13. System Study: Emergency Power System 1998–2012

    SciTech Connect

    T. E. Wierman

    2013-10-01

    This report presents an unreliability evaluation of the emergency power system (EPS) at 104 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2012 for selected components were obtained from the Equipment Performance and Information Exchange (EPIX). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. A statistically significant increasing trend was identified for unreliability (8 hour model) as a function of fiscal year. No statistically significant decreasing trend was identified in the EPS results.

  14. Study of Power Options for Jupiter and Outer Planet Missions

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Fincannon, James

    2015-01-01

    Power for missions to Jupiter and beyond presents a challenging goal for photovoltaic power systems, but NASA missions including Juno and the upcoming Europa Clipper mission have shown that it is possible to operate solar arrays at Jupiter. This work analyzes photovoltaic technologies for use in Jupiter and outer planet missions, including both conventional arrays, as well as analyzing the advantages of advanced solar cells, concentrator arrays, and thin film technologies. Index Terms - space exploration, spacecraft solar arrays, solar electric propulsion, photovoltaic cells, concentrator, Fresnel lens, Jupiter missions, outer planets.

  15. Power System Control Study. Phase I. Integrated Control Techniques. Phase II. Detail Design and System Modeling.

    DTIC Science & Technology

    1981-03-01

    reliable and fault tolerant system. The advanced control technologies integrated include:electric engine start, automatic load manage- ment...Generation System Study .............................. 104 5.2 Reliability Assessment of Power System .................... 119 5.3 EMUX Processor...132 30 Best Main Power System Configuration Based on Reliability Assessment ..................................... 133 31 Main and Emergency Power

  16. Covariate Adjustment Strategy Increases Power in the Randomized Controlled Trial With Discrete-Time Survival Endpoints

    ERIC Educational Resources Information Center

    Safarkhani, Maryam; Moerbeek, Mirjam

    2013-01-01

    In a randomized controlled trial, a decision needs to be made about the total number of subjects for adequate statistical power. One way to increase the power of a trial is by including a predictive covariate in the model. In this article, the effects of various covariate adjustment strategies on increasing the power is studied for discrete-time…

  17. Neustadt's "Presidential Power" and University Governance: A Case Study Analysis.

    ERIC Educational Resources Information Center

    Lander, Byron G.

    The relevance of Richard E. Neustadt's presidential choice making theory to a university presidency is analyzed. This theory, which was introduced in Neustadt's 1960 publication "Presidential Power," is examined in regard to situations that occurred at Kent State University (KSU): the KSU Black United Student (BUS) confrontation with the…

  18. Achievable flatness in a large microwave power antenna study

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Achievable flatness for the microwave power transmission system antenna array was determined. Two configurations were analyzed in detail and evaluated as to their net potential misalignment. Manufacturing, joint slack, assembly, alignment and environmental aspects were considered. Approaches to each aspect were analyzed to minimize their contributions to distortions.

  19. Power Efficient Hydraulic Systems. Volume 1. Study Phase

    DTIC Science & Technology

    1988-07-01

    AIRCRAFT SUBSYSTEMS TABLE 14. Baseline aircraft systems o HYDRAULIC SYSTEM o ELECTRICAL SYSTEM o 8000 PSI, 3 INDEPENDENT SYSTEMS o HVDC POWER o APU...valve (pump) HM hinge moment hp horsepower hr hour HVDC high voltage direct current Hz Hertz (cycles per second) IAP integrated actuator package I.D

  20. Use of mixed radix FFT in electric power systems studies

    SciTech Connect

    Lu, I.D.; Lee, P. )

    1994-07-01

    Radix-2 based Fast Fourier Transform (FFT) routines have been the main stream FFT that are commonly applied to the measurement and analysis of electric power system data. Because of the rigid sampling rates offered by most of the instrument manufacturers and the mathematical limitation imposed by the algorithm of radix-2 FFT, artificial post sampling data windows have been introduced to improve the utility of the radix-2 FFT. The 60 Hz and the 50 Hz based electrical power system frequencies are incompatible with the radix-2 FFT routine to the special requirements of electric power system. Recent advances in the personal computer hardware has opened a new approach to perform the FFT via mixed radix routines. It offers greatly improved flexibility in the selection of a practical data size. And this leads to the elimination of the need of the post sampling software windows. It also allows one to relax or eliminate the requirement of anti-aliasing measures for power system harmonic measurements.

  1. STARFIRE: a commercial tokamak fusion power plant study

    SciTech Connect

    Not Available

    1980-09-01

    This volume contains chapters on each of the following topics: (1) radioactivity, (2) heat transport and energy conversion, (3) tritium systems, (4) electrical storage and power supplies, (5) support structure, (6) cryogenics, (7) instrumentation and control, (8) maintenance and operation, (9) balance of plant design, (10) safety and environmental analysis, (11) economic analysis, and (12) plant construction.

  2. Space Station Freedom electric power system availability study

    NASA Technical Reports Server (NTRS)

    Turnquist, Scott R.

    1990-01-01

    The results are detailed of follow-on availability analyses performed on the Space Station Freedom electric power system (EPS). The scope includes analyses of several EPS design variations, these are: the 4-photovoltaic (PV) module baseline EPS design, a 6-PV module EPS design, and a 3-solar dynamic module EPS design which included a 10 kW PV module. The analyses performed included: determining the discrete power levels that the EPS will operate at upon various component failures and the availability of each of these operating states; ranking EPS components by the relative contribution each component type gives to the power availability of the EPS; determining the availability impacts of including structural and long-life EPS components in the availability models used in the analyses; determining optimum sparing strategies, for storing space EPS components on-orbit, to maintain high average-power-capability with low lift-mass requirements; and analyses to determine the sensitivity of EPS-availability to uncertainties in the component reliability and maintainability data used.

  3. Semi-fuel cell studies for powering underwater devices: integrated design for maximized net power output

    NASA Astrophysics Data System (ADS)

    Cardenas-Valencia, Andres M.; Short, R. Timothy; Adornato, Lori; Langebrake, Larry

    2010-04-01

    Use of sensor systems in water bodies has applications that range from environmental and oceanographic research to port and homeland security. Power sources are often the limiting component for further reduction of sensor system size and weight. We present recent investigations of metal-anode water-activated galvanic cells, specifically water-activated Alcells using inorganic alkali peroxides and solid organic oxidizers (heterocyclic halamines), in a semi-fuel cell configuration (i.e., with cathode species generated in situ and flow-through cells). The oxidizers utilized are inexpensive solid materials that are generally (1) safer to handle than liquid solutions or gases, (2) have inherently higher current and energy capacity (as they are not dissolved), and, (3) if appropriately packaged, will not degrade over time. The specific energy (S.E.) of Al-alkali peroxide was found to be 230 Wh/kg (460 Wh/kg, considering only active materials) in a seven-gram cell. Interestingly, when the cell size was increased (making more area of the catalytic cathode electrode available), the results from a single addition of water in an Al-organic oxidizer cell (weighing ~18 grams) showed an S.E. of about 200 Wh/kg. This scalability characteristic suggests that values in excess of 400 Wh/kg could be obtained in a semi-fuel-cell-like system. In this paper, we also present design considerations that take into account the energy requirements of the pumping devices and show that the proposed oxidizers, and the possible control of the chemical equilibrium of these cathodes in solution, may help reduce this power requirement and hence enhance the overall energetic balance.

  4. Muscle- and pneumatic-powered counterpulsating LVADs: a pilot study.

    PubMed

    Wilde, J C; van Loon, J; Bishop, N D; Shelton, A D; Marten, C; Kolff, W J; Stephenson, L; Baciewicz, F; Nakajima, H; Thomas, G

    1994-03-01

    There is a worldwide interest in supporting the failing heart with a skeletal muscle by either wrapping it around the natural heart (dynamic cardiomyoplasty) or by constructing a skeletal muscle ventricle (SMV) used for counterpulsation. Conventional cardiomyoplasty in many clinics carries an operative mortality rate of 15-20% partly because it requires 6 weeks to train the muscle to contract continually. A flexible, pear-shaped blood pump with an inflatable air chamber was designed and made around which a muscle can be wrapped. The advantage of our design is that it can also be driven by pneumatic power, immediately supporting the circulation of a seriously ill patient while that patient is still on the operating table. After a period of time to allow for revascularization and the subsequent training of the muscle, the external pneumatic power can be gradually discontinued. Then the assisted patient becomes tether-free. If, at any time, the muscle power fails, the pneumatic-powered mechanism can be reactivated. In the preferred approach, the blood pump is connected to the aorta for diastolic counterpulsation. A muscle can either be wrapped around the blood pump directly, or around one of two separate muscle pouches connected to the blood pump. To facilitate surgery, a large pouch is inserted under the musculus latissimus dorsi, which is connected to a blood pump. When stimulated, the muscle will contract over the pouch compressing it and providing power to the blood pump. If it is found that the pressure generated in the pouch cannot meet the aortic blood pressure, it can be augmented by using a pressure amplifier.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Muscle Power Predicts Adolescent Bone Strength: Iowa Bone Development Study

    PubMed Central

    Janz, Kathleen F.; Letuchy, Elena M.; Burns, Trudy L.; Francis, Shelby L.; Levy, Steven M.

    2015-01-01

    Purpose To assess association between lower body muscle power and bone strength, as well as the mediating effect of muscle cross-sectional area (MCSA) on that association. Methods Participants (N=141 males; 162 females) were approximately 17 years. Muscle power was predicted using vertical jump and the Sayers equation. Using peripheral quantitative computed tomography (pQCT), bone strength indices were obtained at two locations of the tibia, corresponding to primary stressors acting upon each site: bone strength index for compression (BSI) at the distal 4% site; density-weighted polar section modulus strength-strain index [SSIp] and cortical bone area (CoA) at the 66% mid-shaft site for torsion. Muscle cross-sectional area (MCSA) was measured at the 66% site. Pearson bivariate and partial correlation coefficients were estimated to quantify the strength of the associations among variables. Direct and indirect mediation model effects were estimated and 95% bootstrap confidence intervals were constructed to test the causal hypothesis. Height and maturity were examined as covariates. Results Pearson correlation coefficients among muscle power, MCSA, and bone strength were statistically significant (p<0.01) and ranged from r=0.54 to 0.78. After adjustment for covariates, associations were reduced (r=0.37 to 0.69) (p<0.01). Mediation models for males for BSI, SSIp, and CoA accounted for 38%, 66%, and 54% of the variance in bone strength, respectively. Models for females for BSI, SSIp, and CoA accounted for 46%, 77%, and 66% of the variance, respectively. Conclusions We found strong and consistent associations, as well as direct and indirect pathways, among muscle power, MCSA, and tibia strength. These results support the use of muscle power as a component of health-related fitness in bone health interventions for older adolescents. PMID:25751769

  6. City of Klamath Falls, Oregon Geothermal Power Plant Feasibility Study

    SciTech Connect

    Brian Brown, PE; Stephen Anderson, PE, Bety Riley

    2011-07-31

    The purpose of the Klamath Falls project is to demonstrate the effectiveness of a combined thermal distribution system and power generation facility. The city of Klamath Falls operates a geothermal district heating system which would appear to be an attractive opportunity to install a power generation system. Since the two wells have operated reliably and consistently over many years, no new sources or resource exploration would be necessary. It appears that it will cost more to construct, operate, maintain and amortize a proposed geothermal facility than the long?term value of the power it would produce. The success of a future project will be determined by whether utility power production costs will remain low and whether costs of construction, operations, or financing may be reduced. There are areas that it would be possible to reduce construction cost. More detailed design could enable the city to obtain more precise quotes for components and construction, resulting in reduction in contingency projections. The current level of the contingency for uncertainty of costs is between $200,000 and $300,000. Another key issue with this project appears to be operation cost. While it is expected that only minimal routine monitoring and operating expenses will occur, the cost of water supply and waste water disposal represents nearly one quarter of the value of the power. If the cost of water alone could be reduced, the project could become viable. In addition, the projected cost of insurance may be lower than estimated under a city?wide policy. No provisions have been made for utilization of federal tax incentives. If a transaction with a third-party owner/taxpayer were to be negotiated, perhaps the net cost of ownership could be reduced. It is recommended that these options be investigated to determine if the costs and benefits could be brought together. The project has good potential, but like many alternative energy projects today, they only work economically if the

  7. A test for adequate wastewater treatment based on glutathione S transferase isoenzyme profile.

    PubMed

    Grammou, A; Samaras, P; Papadimitriou, C; Papadopoulos, A I

    2013-04-01

    Discharge to the environment of treated or non-treated municipal wastewater imposes several threats to coastal and estuarine ecosystems which are difficult to assess. In our study we evaluate the use of the isoenzyme profile of glutathione S transferase (GST) in combination with the kinetic characteristics of the whole enzyme and of heme peroxidase, as a test of adequate treatment of municipal wastewater. For this reason, Artemia nauplii were incubated in artificial seawater prepared by wastewater samples, such as secondary municipal effluents produced by a conventional activated sludge unit and advanced treated effluents produced by the employment of coagulation, activated carbon adsorption and chlorination as single processes or as combined ones. Characteristic changes of the isoenzyme pattern and the enzymes' kinetic properties were caused by chlorinated secondary municipal effluent or by secondary non-chlorinated effluent. Advanced treatment by combination of coagulation and/or carbon adsorption resulted to less prominent changes, suggesting more adequate treatment. Our results suggest that GST isoenzyme profile in combination with the kinetic properties of the total enzyme family is a sensitive test for the evaluation of the adequateness of the treatment of reclaimed wastewater and the reduction of potentially harmful compounds. Potentially, it may offer a 'fingerprint' characteristic of a particular effluent and probably of the treatment level it has been subjected.

  8. T55 power turbine rotor multiplane-multispeed balancing study

    NASA Technical Reports Server (NTRS)

    Martin, M. R.

    1982-01-01

    A rotordynamic analysis of the T55-L-11C engine was used to evaluate the balancing needs of the power turbine and to optimize the balancing procedure. As a result, recommendations were made for implementation of a multiplane-multispeed balancing plan. Precision collars for the attachment of trial weights to a slender rotor were designed enabling demonstration balancing on production hardware. The quality of the balance was then evaluated by installing a high speed balanced power turbine in an engine and running in a test cell at the Corpus Christi Army depot. The engine used had been tested prior to the turbine changeout and showed acceptable overall vibration levels for the engine were significantly reduced, demonstrating the ability of multiplane-multispeed balancing to control engine vibration.

  9. Contingency Power Study for Short Haul Civil Tiltrotor

    NASA Technical Reports Server (NTRS)

    Eisenberg, Joseph D. (Technical Monitor); Wait, John

    2003-01-01

    AlliedSignal Engines (AE) defined a number of concepts that significantly increased the horsepower of a turboshaft engine to accommodate the loss of an engine and enable the safe landing of a twin-engined, 40-passenger, short haul civil tiltrotor. From these concepts, "Water/Methanol Injection," a "Better Power Turbine Than Required," and a "Secondary Combustor For Interturbine Reheat" were chosen, based on system safety and economics, for more detailed examination. Engine performance, mission, and cost analysis of these systems indicated contingency power levels of 26 to 70 percent greater than normal rated takeoff could be attained for short durations, thus enabling direct operating cost savings between 2 and 6 percent.

  10. Case study on the US superconducting power transmission program

    SciTech Connect

    Hammel, E.F.

    1996-02-01

    After the 1911 discovery of superconductivity (the abrupt loss of electrical resistance in certain materials at very low temperatures), attempts were made to make practical use of this phenomenon. Initially these attempts failed, but in the early 1960s (after 50 years of research) they succeeded. By then, the projected growth in the production and consumption of electrical energy required much higher capacity power transmission capabilities than were available or likely to become available from incremental improvements in existing transmission technology. Since superconductors were capable in principle of transmitting huge amounts of power, research programs to develop and demonstrate superconducting transmission lines were initiated in the US and abroad. The history of the US program, including the participants, their objectives, funding and progress made, is outlined. Since the R&D program was terminated before the technology was completely demonstrated, the reasons for and consequences of this action are discussed in a final section.

  11. Observing power blackouts from space - A disaster related study

    NASA Astrophysics Data System (ADS)

    Aubrecht, C.; Elvidge, C. D.; Ziskin, D.; Baugh, K. E.; Tuttle, B.; Erwin, E.; Kerle, N.

    2009-04-01

    In case of emergency disaster managers worldwide require immediate information on affected areas and estimations of the number of affected people. Natural disasters such as earthquakes, hurricanes, tornados, wind and ice storms often involve failures in the electrical power generation system and grid. Near real time identification of power blackouts gives a first impression of the area affected by the event (Elvidge et al. 2007), which can subsequently be linked to population estimations. Power blackouts disrupt societal activities and compound the difficulties associated with search and rescue, clean up, and the provision of food and other supplies following a disastrous event. Locations and spatial extents of power blackouts are key considerations in planning and execution of the primary disaster missions of emergency management organizations. To date only one satellite data source has been used successfully for the detection of power blackouts. Operated by NOAA's National Geophysical Data Center (NGDC) the U.S. Air Force Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) offers a unique capability to observe lights present at the Earth's surface at night. Including a pair of visible and thermal spectral bands and originally designed to detect moonlit clouds, this sensor enables mapping of lights from cities and towns, gas flares and offshore platforms, fires, and heavily lit fishing boats. The low light imaging of the OLS is accomplished using a photomultiplier tube (PMT) which intensifies the visible band signal at night. With 14 orbits collected per day and a 3.000 km swath width, each OLS is capable of collecting a complete set of images of the Earth every 24 hours. NGDC runs the long-term archive for OLS data with the digital version extending back to 1992. OLS data is received by NGDC in near real time (1-2 hours from acquisition) and subscription based services for the near real time data are provided for users all over the

  12. Mahreb power-plant-project assessment of TOR for feasibility study. Export trade information

    SciTech Connect

    Schmidt, A.D.; Ahimaz, F.J.

    1992-01-01

    The study endorses the proposed terms of reference for the feasibility study of the Mahreb Power Generation Project in Yemen. It is a reasonable and practical approach to meet the immediate need for additional power in the country. The outline for the feasibility study also seeks a long term solution for an economic and technically sound power generating system to meet future power needs. U.S. firms have been competitive in international tenders for supplying the type of services and equipment needed for the Mahreb Power Project. Because it is a gas turbine power generation project and the opportunities it offers US equipment manufacturers and contractors, the study recommends that the U.S. Trade and Development Program (TDP) fund the feasibility study.

  13. Parametric study of potential early commercial MHD power plants

    NASA Technical Reports Server (NTRS)

    Hals, F. A.

    1979-01-01

    Three different reference power plant configurations were considered with parametric variations of the various design parameters for each plant. Two of the reference plant designs were based on the use of high temperature regenerative air preheaters separately fired by a low Btu gas produced from a coal gasifier which was integrated with the power plant. The third reference plant design was based on the use of oxygen enriched combustion air preheated to a more moderate temperature in a tubular type metallic recuperative heat exchanger which is part of the bottoming plant heat recovery system. Comparative information was developed on plant performance and economics. The highest net plant efficiency of about 45 percent was attained by the reference plant design with the use of a high temperature air preheater separately fired with the advanced entrained bed gasifier. The use of oxygen enrichment of the combustion air yielded the lowest cost of generating electricity at a slightly lower plant efficiency. Both of these two reference plant designs are identified as potentially attractive for early MHD power plant applications.

  14. An observational study of powered wheelchair provision in Italy.

    PubMed

    Salatino, Claudia; Andrich, Renzo; Converti, R M; Saruggia, M

    2016-01-01

    Powered wheelchairs are complex and expensive assistive devices that must be selected and configured on the basis of individual user needs, lifestyle, motivation, driving ability, and environment. Providing agencies often require evidence that their financial investment will lead to a successful outcome. The authors surveyed a sample of 79 users who had obtained powered wheelchairs from a Regional Health Service in Italy in the period 2008-2013. Follow-up interviews were conducted at the users' homes in order to collect information about wheelchair use, and its effectiveness, usefulness, and economic impact. The instruments used in the interviews included an introductory questionnaire, QUEST (Quebec User Evaluation of Satisfaction with Assistive Technology), PIADS (Psychosocial Impact of Assistive Devices Scale), FABS/M (Facilitators and Barriers Survey/Mobility), and SCAI (Siva Cost Analysis Instrument). The results indicated positive outcomes, especially in relation to user satisfaction and psychosocial impact. A number of barriers were identified in various settings that sometimes restrict user mobility, and suggest corrective actions. The provision of a powered wheelchair generated considerable savings in social costs for most users: an average of about $38,000 per person over a projected 5-year period was estimated by comparing the cost of the intervention with that of non-intervention.

  15. Overview of L-H power threshold studies in NSTX

    NASA Astrophysics Data System (ADS)

    Maingi, R.; Kaye, S. M.; Bell, R. E.; Biewer, T. M.; Chang, C. S.; Gates, D. A.; Gerhardt, S. P.; Hosea, J.; LeBlanc, B. P.; Meyer, H.; Mueller, D.; Park, G.-Y.; Raman, R.; Sabbagh, S. A.; Stevenson, T. A.; Wilson, J. R.

    2010-06-01

    A summary of results from recent L-H power threshold (PLH) experiments in the National Spherical Torus Experiment is presented. First PLH (normalized linearly by plasma density) was found to be a minimum in double-null configuration, tending to increase as the plasma was shifted more strongly towards lower- or upper-single null configuration with either neutral beam or rf heating. The measured PLH/ne was comparable with neutral beam or rf heating, suggesting that rotation was not playing a dominant role in setting the value of PLH. The role of triangularity (δbot) in setting PLH/ne is less clear: while 50% less auxiliary heating power was required to access H-mode at low δbot than at high δbot, the high δbot discharges had lower ohmic heating and higher dW/dt, leading to comparable loss of power over a range of δbot. In addition, the dependences of PLH on the density, species (helium versus deuterium), plasma current, applied non-axisymmetric error fields and lithium wall conditioning are summarized.

  16. Nebulized antibiotics. An adequate option for treating ventilator-associated respiratory infection?

    PubMed

    Rodríguez, A; Barcenilla, F

    2015-03-01

    Ventilator-associated tracheobronchitis (VAT) is a frequent complication in critical patients. The 90% of those who develop it receive broad-spectrum antibiotic (ATB) treatment, without any strong evidence of its favorable impact. The use of nebulized ATB could be a valid treatment option, to reduce the use of systemic ATB and the pressure of selection on the local flora. Several studies suggest that an adequate nebulization technique can ensure high levels of ATB even in areas of lung consolidation, and to obtain clinical and microbiological cure. New studies are needed to properly assess the impact of treatment with nebulized ATB on the emergence of resistance.

  17. An advanced concept secondary power systems study for an advanced transport technology aircraft

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The application of advanced technology to the design of an integrated secondary power system for future near-sonic long-range transports was investigated. The study showed that the highest payoff is achieved by utilizing secondary power equipment that contributes to minimum cruise drag. This is best accomplished by the use of the dedicated auxiliary power unit concept (inflight APU) as the prime power source for an airplane with a body-mounted engine or by the use of the internal engine generator concept (electrical power extraction from the propulsion engine) for an airplane with a wing-pod-mounted engine.

  18. An experimental study of potential residential and commercial applications of small-scale hybrid power systems

    NASA Astrophysics Data System (ADS)

    Acosta, Michael Anthony

    The research presented in this thesis provides an understanding of small-scale hybrid power systems. Experiments were conducted to identify potential applications of renewable energy in residential and commercial applications in the Rio Grande Valley of Texas. Solar and wind energy converted into electric energy was stored in batteries and inverted to power common household and commercial appliances. Several small to medium size hybrid power systems were setup and utilized to conduct numerous tests to study renewable energy prospects and feasibility for various applications. The experimental results obtained indicate that carefully constructed solar power systems can provide people living in isolated communities with sufficient energy to consistently meet their basic power needs.

  19. Combining Multiple Hypothesis Testing with Machine Learning Increases the Statistical Power of Genome-wide Association Studies

    PubMed Central

    Mieth, Bettina; Kloft, Marius; Rodríguez, Juan Antonio; Sonnenburg, Sören; Vobruba, Robin; Morcillo-Suárez, Carlos; Farré, Xavier; Marigorta, Urko M.; Fehr, Ernst; Dickhaus, Thorsten; Blanchard, Gilles; Schunk, Daniel; Navarro, Arcadi; Müller, Klaus-Robert

    2016-01-01

    The standard approach to the analysis of genome-wide association studies (GWAS) is based on testing each position in the genome individually for statistical significance of its association with the phenotype under investigation. To improve the analysis of GWAS, we propose a combination of machine learning and statistical testing that takes correlation structures within the set of SNPs under investigation in a mathematically well-controlled manner into account. The novel two-step algorithm, COMBI, first trains a support vector machine to determine a subset of candidate SNPs and then performs hypothesis tests for these SNPs together with an adequate threshold correction. Applying COMBI to data from a WTCCC study (2007) and measuring performance as replication by independent GWAS published within the 2008–2015 period, we show that our method outperforms ordinary raw p-value thresholding as well as other state-of-the-art methods. COMBI presents higher power and precision than the examined alternatives while yielding fewer false (i.e. non-replicated) and more true (i.e. replicated) discoveries when its results are validated on later GWAS studies. More than 80% of the discoveries made by COMBI upon WTCCC data have been validated by independent studies. Implementations of the COMBI method are available as a part of the GWASpi toolbox 2.0. PMID:27892471

  20. Combining Multiple Hypothesis Testing with Machine Learning Increases the Statistical Power of Genome-wide Association Studies

    NASA Astrophysics Data System (ADS)

    Mieth, Bettina; Kloft, Marius; Rodríguez, Juan Antonio; Sonnenburg, Sören; Vobruba, Robin; Morcillo-Suárez, Carlos; Farré, Xavier; Marigorta, Urko M.; Fehr, Ernst; Dickhaus, Thorsten; Blanchard, Gilles; Schunk, Daniel; Navarro, Arcadi; Müller, Klaus-Robert

    2016-11-01

    The standard approach to the analysis of genome-wide association studies (GWAS) is based on testing each position in the genome individually for statistical significance of its association with the phenotype under investigation. To improve the analysis of GWAS, we propose a combination of machine learning and statistical testing that takes correlation structures within the set of SNPs under investigation in a mathematically well-controlled manner into account. The novel two-step algorithm, COMBI, first trains a support vector machine to determine a subset of candidate SNPs and then performs hypothesis tests for these SNPs together with an adequate threshold correction. Applying COMBI to data from a WTCCC study (2007) and measuring performance as replication by independent GWAS published within the 2008–2015 period, we show that our method outperforms ordinary raw p-value thresholding as well as other state-of-the-art methods. COMBI presents higher power and precision than the examined alternatives while yielding fewer false (i.e. non-replicated) and more true (i.e. replicated) discoveries when its results are validated on later GWAS studies. More than 80% of the discoveries made by COMBI upon WTCCC data have been validated by independent studies. Implementations of the COMBI method are available as a part of the GWASpi toolbox 2.0.

  1. Space-Based Solar Power Conversion and Delivery Systems Study. Volume 1: Executive Summary

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The research concerning space-based solar power conversion and delivery systems is summarized. The potential concepts for a photovoltaic satellite solar power system was studied with emphasis on ground output power levels of 5,000 MW and 10,000 MW. A power relay satellite, and certain aspects of the economics of these systems were also studied. A second study phase examined in greater depth the technical and economic aspects of satellite solar power systems. Throughout this study, the focus was on the economics of satellite solar power. The results indicate technical feasibility of the concept, and provide a preliminary economic justification for the first phase of a substantial development program. A development program containing test satellites is recommended. Also, development of alternative solar cell materials (other than silicon) is recommended.

  2. Kenya geothermal private power project: A prefeasibility study

    SciTech Connect

    Not Available

    1992-10-01

    Twenty-eight geothermal areas in Kenya were evaluated and prioritized for development. The prioritization was based on the potential size, resource temperature, level of exploration risk, location, and exploration/development costs for each geothermal area. Suswa, Eburru and Arus are found to offer the best short-term prospects for successful private power development. It was found that cost per kill developed are significantly lower for the larger (50MW) than for smaller-sized (10 or 20 NW) projects. In addition to plant size, the cost per kill developed is seen to be a function of resource temperature, generation mode (binary or flash cycle) and transmission distance.

  3. Satellite Power System (SPS) magnetron tube assessment study

    NASA Technical Reports Server (NTRS)

    Brown, W. C.

    1981-01-01

    The data base was extended with respect to the magnetron directional amplifier and its operating parameters that are pertinent to its application in the solar power satellite. On the basis of the resulting extended data base the design of a magnetron was outlined that would meet the requirements of the SPS application and a technology program was designed that would result in its development. The proposed magnetron design for the SPS is a close scale of the microwave oven magnetron, and resembles it closely physically and electrically.

  4. Co-Simulation of Detailed Whole Building with the Power System to Study Smart Grid Applications

    SciTech Connect

    Makhmalbaf, Atefe; Fuller, Jason C.; Srivastava, Viraj; Ciraci, Selim; Daily, Jeffrey A.

    2014-12-24

    Modernization of the power system in a way that ensures a sustainable energy system is arguably one of the most pressing concerns of our time. Buildings are important components in the power system. First, they are the main consumers of electricity and secondly, they do not have constant energy demand. Conventionally, electricity has been difficult to store and should be consumed as it is generated. Therefore, maintaining the demand and supply is critical in the power system. However, to reduce the complexity of power models, buildings (i.e., end-use loads) are traditionally modeled and represented as aggregated “dumb” nodes in the power system. This means we lack effective detailed whole building energy models that can support requirements and emerging technologies of the smart power grid. To gain greater insight into the relationship between building energy demand and power system performance, it is important to constitute a co-simulation framework to support detailed building energy modeling and simulation within the power system to study capabilities promised by the modern power grid. This paper discusses ongoing work at Pacific Northwest National Laboratory and presents underlying tools and framework needed to enable co-simulation of building, building energy systems and their control in the power system to study applications such as demand response, grid-based HVAC control, and deployment of buildings for ancillary services. The optimal goal is to develop an integrated modeling and simulation platform that is flexible, reusable, and scalable. Results of this work will contribute to future building and power system studies, especially those related to the integrated ‘smart grid’. Results are also expected to advance power resiliency and local (micro) scale grid studies where several building and renewable energy systems transact energy directly. This paper also reviews some applications that can be supported and studied using the framework introduced

  5. Satellite Power Study (SPS) concept definition study (Exhibit D). Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Hanley, G. M.

    1981-01-01

    Efforts concentrated on updating of the Rockwell reference concept, definition of new system options, studies of special emphasis topics, further definition of the transportation system, and further program definition. The Rockwell reference satellite concept has a gallium arsenide (GaAs) solar cell array having flat concentrators with an effective concentration ratio of 1.83at end of life. Alternatives to this concept includes solid state power amplifiers or magnetrons for dc/RF conversion and multibandgap solar cells for solar to dc energy conversion. Two solid state concepts were studied. It was determined that the magnetron approach was the lowest mass and cost system.

  6. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  7. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  8. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  9. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  10. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  11. Effect of cadence selection on peak power and time of power production in elite BMX riders: A laboratory based study.

    PubMed

    Rylands, Lee P; Roberts, Simon J; Hurst, Howard T; Bentley, Ian

    2016-08-01

    The aims of this study were to analyse the optimal cadence for peak power production and time to peak power in bicycle motocross (BMX) riders. Six male elite BMX riders volunteered for the study. Each rider completed 3 maximal sprints at a cadence of 80, 100, 120 and 140 revs · min(-1) on a laboratory Schoberer Rad Messtechnik (SRM) cycle ergometer in isokinetic mode. The riders' mean values for peak power and time of power production in all 3 tests were recorded. The BMX riders produced peak power (1105 ± 139 W) at 100 revs · min(-1) with lower peak power produced at 80 revs · min(-1) (1060 ± 69 W, (F(2,15) = 3.162; P = .266; η(2) = 0.960), 120 revs · min(-1) (1077 ± 141 W, (F(2,15) = 4.348; P = .203; η(2) = 0.970) and 140 revs · min(-1) (1046 ± 175 W, (F(2,15) = 12.350; P = 0.077; η(2) = 0.989). The shortest time to power production was attained at 120 revs · min(-1) in 2.5 ± 1.07 s. Whilst a cadence of 80 revs · min(-1) (3.5 ± 0.8 s, (F(2,15) = 2.667; P = .284; η(2) = 0.800) 100 revs · min(-1) (3.00 ± 1.13 s, (F(2,15) = 24.832; P = .039; η(2) = 0.974) and 140 revs · min(-1) (3.50 ± 0.88 s, (F(2,15) = 44.167; P = .006; η(2) = 0.967)) all recorded a longer time to peak power production. The results indicate that the optimal cadence for producing peak power output and reducing the time to peak power output are attained at comparatively low cadences for sprint cycling events. These findings could potentially inform strength and conditioning training to maximise dynamic force production and enable coaches to select optimal gear ratios.

  12. Radar Men on the Moon: A Brief Survey of Fission Surface Power Studies

    SciTech Connect

    Bennett, Gary L.

    2008-01-21

    This paper reviews some of the salient fission surface power studies, including those dating back to the early SNAP (Systems for Nuclear Auxiliary Power) program. Particular attention will be focused on the more recent Space Exploration Initiative (including the related Synthesis Group report) and Vision for Space Exploration. Commonalties in these studies will be noted; for example, many studies have shown that powers in the range of 100 kWe are required for human-tended bases on the Moon and Mars. Just as advanced human civilizations depend upon electrical power so will advanced, human-occupied lunar and Mars bases with powers rising into the megawatt level for bases with manufacturing and resource utilization capabilities. The role of radioisotope power sources will also be noted.

  13. Maintenance of an Adequate Dental Hygiene Education System.

    ERIC Educational Resources Information Center

    Ley, Eugene; And Others

    1984-01-01

    Administrative decisions about the future of dental hygiene programs are often based on inadequate information about employment trends and about the importance of the dental hygienist in dental practices. Studies indicate that demand for dental hygiene services will remain high in the 1980s. (Author/MLW)

  14. Arabidopsis: an adequate model for dicot root systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the search for answers to pressing root developmental genetic issues, plant science has turned to a small genome dicot plant (Arabidopsis) to be used as a model to study and use to develop hypotheses for testing other species. Through out the published research only three classes of root are des...

  15. Power of Models in Longitudinal Study: Findings from a Full-Crossed Simulation Design

    ERIC Educational Resources Information Center

    Fang, Hua; Brooks, Gordon P.; Rizzo, Maria L.; Espy, Kimberly Andrews; Barcikowski, Robert S.

    2009-01-01

    Because the power properties of traditional repeated measures and hierarchical multivariate linear models have not been clearly determined in the balanced design for longitudinal studies in the literature, the authors present a power comparison study of traditional repeated measures and hierarchical multivariate linear models under 3…

  16. Solar power satellite: System definition study. Part 1, volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A study of the solar power satellite system, which represents a means of tapping baseload electric utility power from the sun on a large scale, was summarized. Study objectives, approach, and planning are presented along with an energy conversion evaluation. Basic requirements were considered in regard to space transportation, construction, and maintainability.

  17. Smoking Cessation/Prevention in the Air Force: How Adequate

    DTIC Science & Technology

    2007-11-02

    FNP , Com. Member Approval DaW APPROVED: F.G. Abdellah, EdD, ScD, RN, FAAN Date Dean CURRICULUM VITAE Name: Cheryl Anita Udensi Permanent Address...sample of charts and client interview was employed to compare providers’ documented practice protocols with established guidelines set by the Department of...validity in smoking cessation practices was utilized. A pilot study was done to determine intercoder reliability. Descriptive statistics were utilized to

  18. Do British travel agents provide adequate health advice for travellers?

    PubMed Central

    Lawlor, D A; Burke, J; Bouskill, E; Conn, G; Edwards, P; Gillespie, D

    2000-01-01

    Travel-related illness is a burden for primary care, with more than two million travellers consulting a general practitioner each year. The annual cost of travel-related illness in the United Kingdom is 11 million Pounds. Travel agents are in a unique position to influence this burden as the most common and most serious problems are preventable with simple advice and/or immunisation. This study, using covert researchers, suggests this potential is not being fully utilised. PMID:10954940

  19. The Air Force Physical Fitness Program is it Adequate?

    DTIC Science & Technology

    1999-04-01

    20 Table 3 Cardiovascular Fitness Classifications ( American Heart Association ). ...............20 Table 4 Norms... American Heart Association ). These two factors are high blood pressure and poor blood cholesterol levels.5 A study done at Stanford University showed that...and Rhyming, defined them and table 3 shows the American Heart Association �s classifications. Table 1 Air Force Fitness Standards.6 Minimum VO2 score

  20. Are the current Australian sun exposure guidelines effective in maintaining adequate levels of 25-hydroxyvitamin D?

    PubMed

    Kimlin, Michael; Sun, Jiandong; Sinclair, Craig; Heward, Sue; Hill, Jane; Dunstone, Kimberley; Brodie, Alison

    2016-01-01

    An adequate vitamin D status, as measured by serum 25-hydroxyvitamin D (25(OH)D) concentration, is important in humans for maintenance of healthy bones and muscle function. Serum 25(OH)D concentration was assessed in participants from Melbourne, Australia (37.81S, 144.96E), who were provided with the current Australian guidelines on sun exposure for 25(OH)D adequacy (25(OH)D ≥50 nmol/L). Participants were interviewed in February (summer, n=104) and August (winter, n=99) of 2013. Serum 25(OH)D concentration was examined as a function of measures of sun exposure and sun protection habits with control of key characteristics such as dietary intake of vitamin D, body mass index (BMI) and skin colour, that may modify this relationship. The mean 25(OH)D concentration in participants who complied with the current sun exposure guidelines was 67.3 nmol/L in summer and 41.9 nmol/L in winter. At the end of the study, 69.3% of participants who complied with the summer sun exposure guidelines were 25(OH)D adequate, while only 27.6% of participants who complied with the winter sun exposure guidelines were 25(OH)D adequate at the end of the study. The results suggest that the current Australian guidelines for sun exposure for 25(OH)D adequacy are effective for most in summer and ineffective for most in winter. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

  1. Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt

    PubMed Central

    Jones, Emma; McLean, Rachael; Davies, Briar; Hawkins, Rochelle; Meiklejohn, Eva; Ma, Zheng Feei; Skeaff, Sheila

    2016-01-01

    Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8–10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC), a fingerpick blood sample for Thyroglobulin (Tg) concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ). The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415) was 116 μg/L (females 106 μg/L, males 131 μg/L) indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100–199 μg/L). The median Tg concentration was 8.7 μg/L, which was <10 μg/L confirming adequate iodine status. There was a significant difference in UIC by sex (p = 0.001) and ethnicity (p = 0.006). The mean iodine intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate. PMID:27196925

  2. The Nigerian health care system: Need for integrating adequate medical intelligence and surveillance systems

    PubMed Central

    Welcome, Menizibeya Osain

    2011-01-01

    Objectives: As an important element of national security, public health not only functions to provide adequate and timely medical care but also track, monitor, and control disease outbreak. The Nigerian health care had suffered several infectious disease outbreaks year after year. Hence, there is need to tackle the problem. This study aims to review the state of the Nigerian health care system and to provide possible recommendations to the worsening state of health care in the country. To give up-to-date recommendations for the Nigerian health care system, this study also aims at reviewing the dynamics of health care in the United States, Britain, and Europe with regards to methods of medical intelligence/surveillance. Materials and Methods: Databases were searched for relevant literatures using the following keywords: Nigerian health care, Nigerian health care system, and Nigerian primary health care system. Additional keywords used in the search were as follows: United States (OR Europe) health care dynamics, Medical Intelligence, Medical Intelligence systems, Public health surveillance systems, Nigerian medical intelligence, Nigerian surveillance systems, and Nigerian health information system. Literatures were searched in scientific databases Pubmed and African Journals OnLine. Internet searches were based on Google and Search Nigeria. Results: Medical intelligence and surveillance represent a very useful component in the health care system and control diseases outbreak, bioattack, etc. There is increasing role of automated-based medical intelligence and surveillance systems, in addition to the traditional manual pattern of document retrieval in advanced medical setting such as those in western and European countries. Conclusion: The Nigerian health care system is poorly developed. No adequate and functional surveillance systems are developed. To achieve success in health care in this modern era, a system well grounded in routine surveillance and medical

  3. Investigating wind power`s effective capacity: A case study in the Caribbean Island of La Martinique

    SciTech Connect

    Perez, R.; Germa, J.M.; Bailey, B.

    1996-12-31

    In this paper, we report on the experimental determination of the effective capacity of wind and photovoltaic (PV) power generation with respect to the utility load requirements of the Island of La Martinique. La Martinique is a French Overseas Department in the Caribbean Sea. The case study spans two years, 1990 and 1991. We consider wind generation at three locations in different wind regimes, and PV generation for fixed and tracking flat plate systems. The results presented include: (1) An overview of typical solar and wind power output at each considered site, presented in contrast to the Island`s electric load requirements; and (2) Effective capacities quantified for each resource as a function of penetration in the utility generation mix. 7 refs., 6 figs.

  4. Odds of Getting Adequate Physical Activity by Dog Walking

    PubMed Central

    Soares, Jesus; Epping, Jacqueline N.; Owens, Chantelle J.; Brown, David R.; Lankford, Tina J.; Simoes, Eduardo J.; Caspersen, Carl J.

    2015-01-01

    Background We aimed to determine the likelihood that adult dog owners who walk their dogs will achieve a healthy level of moderate-intensity (MI) physical activity (PA), defined as at least 150 mins/wk. Methods We conducted a systematic search of 6 databases with data from 1990–2012 on dog owners’ PA, to identify those who achieved MIPA. To compare dog-walkers’ performance with non–dog walkers, we used a random effects model to estimate the unadjusted odds ratio (OR) and corresponding 95% confidence interval (CI). Results We retrieved 9 studies that met our inclusion criterion and allowed OR calculations. These yielded data on 6980 dog owners aged 18 to 81 years (41% men). Among them, 4463 (63.9%) walked their dogs. Based on total weekly PA, 2710 (60.7%) dog walkers, and 950 (37.7%) non–dog walkers achieved at least MIPA. The estimated OR was 2.74 (95% CI 2.09–3.60). Conclusion Across 9 published studies, almost 2 in 3 dog owners reported walking their dogs, and the walkers are more than 2.5 times more likely to achieve at least MIPA. These findings suggest that dog walking may be a viable strategy for dog owners to help achieve levels of PA that may enhance their health. PMID:24733365

  5. The need for adequate ethical guidelines for qualitative health research.

    PubMed

    Guerriero, Iara Coelho Zito; Dallari, Sueli Gandolfi

    2008-01-01

    This paper discusses adequacy as to the application of Brazilian guidelines, Resolution 196/96(1) and complementaries to qualitative health researches, considering that these are based on non-positivistic paradigms. Frequently, decisions about the research are made together with the studied community. There is a concern with justice and social change. And, since subjectivity can be considered their privileged instrument, such researchers seek a balance between objectivity and subjectivity, discussing how to overcome the researcher's view. We have studied the application and the concept of research found in international and in the Brazilian guidelines. We have noticed that they adopt a positivist conception of research, which establishes 1) the hypothesis test, 2) that all procedures are previously defined by the researcher; 3) neutrality of the researcher and of the knowledge produced. We will present some characteristics of qualitative research; the ethical implications in the way as qualitative research is conceived in non-positivist paradigms and a brief history of these guidelines. Our conclusion: it is inadequate to analyze qualitative researches using these documents, and we suggest the design of specific guidelines for them.

  6. Marital power process of Korean men married to foreign women: a qualitative study.

    PubMed

    Kim, Miyoung; Park, Gyeong Sook; Windsor, Carol

    2013-03-01

    This study explored how Korean men married to migrant women construct meaning around married life. Data were collected through in-depth interviews with 10 men who had had been married to migrant women for ≥ 2 years. Data collection and analysis were performed concurrently using a grounded theory approach. The core category generated was the process of sustaining a family unit. The men came to understand the importance of a distribution of power within the family in sustaining the family unit. Constituting this process were four stages: recognizing an imbalance of power, relinquishing power, empowering, and fine-tuning the balance of power. This study provides important insight into the dynamics of marital power from men's point of view by demonstrating a link between the way people adjust to married life and the process by which married couples adjust through the distribution and redistribution of power.

  7. [Selection of power force for the electrocardiostimulating apparatus and the study of the characteristics of the battery "Krona VTs"].

    PubMed

    Dubrovskiĭ, I A; Ostashkin, S P

    1976-01-01

    An independent power supply of electrocardiostimulators improves the electric safety of the patient and of the attending staff, does not produce any additional interferences with the functioning of instrumentation and makes it possible to design mobile portable devices. The storage battery used as a power source should have a sufficiently great capacity, provide for some back-up time ensuring normal operation of the apparatus, have small dimensions and mass. These requirements are met with most adequately by the air-zinc battery "Krona Vts". To estimate the continuous operation time for the apparatus experimental characteristics of the battery's pulse discharge are given.

  8. New Visions in Asian American Studies. Diversity, Community, Power.

    ERIC Educational Resources Information Center

    Ng, Franklin, Ed.; And Others

    This collection of essays from the eighth national conference of the Association for Asian American Studies is organized into four sections: history and women's studies; social science; literature; and Hawaiian studies. The following papers are included: (1) "History and Women Studies" (Yung); (2) "From Old to New Plantations: Labor's Growing…

  9. Solar power satellite rectenna design study: Directional receiving elements and parallel-series combining analysis

    NASA Technical Reports Server (NTRS)

    Gutmann, R. J.; Borrego, J. M.

    1978-01-01

    Rectenna conversion efficiencies (RF to dc) approximating 85 percent were demonstrated on a small scale, clearly indicating the feasibility and potential of efficiency of microwave power to dc. The overall cost estimates of the solar power satellite indicate that the baseline rectenna subsystem will be between 25 to 40 percent of the system cost. The directional receiving elements and element extensions were studied, along with power combining evaluation and evaluation extensions.

  10. Evaluation of space adequateness of shrimp farms in Southern Brazil.

    PubMed

    Freitas, Rodrigo R; Hartmann, Carlos; Tagliani, Paulo R A; Poersch, Luís H

    2011-09-01

    In Rio Grande do Sul State, there are four marine shrimp (Litopenaeus vannamei) farms in the municipal districts of São José do Norte and Rio Grande, and other four with previous license for operation. Thus, the present study aimed to identify and characterize areas for marine shrimp farming located in the Southern portion of the Patos Lagoon estuary (32º00'S 52º00'W) by employing the analysis of satellite remote sensing (Landsat TM and ETM+/Google Earth), airborne remote sensing (35mm system ADAR 1000), terrestrial remote sensing (RICOH 500SE), and field expeditions, integrating data in a Geographical Information System (IDRISI Andes). As a result, the enterprises were built on coastal fields or in obliterated dune areas, which are favorable for cultivation. The proximity of possible consuming markets and local labor, relatively good access roads and local technical support also favor the projects. However, there must be caution in terms of changes in the original projects, which could cause environmental impacts and noncompliance of environmental norms, such as the occupation of salt marsh areas. Based on the obtained information, instruments can be created to help inherent legal decision-making to manage the activity for futures enterprises.

  11. Does the World Health Organization criterion adequately define glaucoma blindness?

    PubMed Central

    Mokhles, P; Schouten, JSAG; Beckers, HJM; Webers, CAB

    2017-01-01

    Purpose Blindness in glaucoma is difficult to assess with merely the use of the current World Health Organization (WHO) definition (a visual field restricted to 10° in a radius around central fixation), as this criterion does not cover other types of visual field loss that are encountered in clinical practice and also depict blindness. In this study, a 5-point ordinal scale was developed for the assessment of common visual field defect patterns, with the purpose of comparing blindness as outcome to the findings with the WHO criterion when applied to the same visual fields. The scores with the two methods were compared between two ophthalmologists. In addition, the variability between these assessors in assessing the different visual field types was determined. Methods Two glaucoma specialists randomly assessed a sample of 423 visual fields from 77 glaucoma patients, stripped of all indices and masked for all patient variables. They applied the WHO criterion and a 5-point ordinal scale to all visual fields for the probability of blindness. Results The WHO criterion was mostly found applicable and in good agreement for both assessors to visual fields depicting central island of vision or a temporal crescent. The percentage of blindness scores was higher when using the ordinal scale, 21.7% and 19.6% for assessors A and B, respectively, versus 14.4% and 11.3% for the WHO criterion. However, Kappa was lower, 0.71 versus 0.78 for WHO. Conclusions The WHO criterion is strictly applied and shows good agreement between assessors; however, blindness does not always fit this criterion. More visual fields are labeled as blind when a less stringent criterion is used, but this leads to more interobserver variability. A new criterion that describes the extent, location, and depth of visual field defects together with their consequence for the patient’s quality of life is needed for the classification of glaucoma blindness. PMID:28280297

  12. Power System Study for Renewable Energy Interconnection in Malaysia

    NASA Astrophysics Data System (ADS)

    Askar, O. F.; Ramachandaramurthy, V. K.

    2013-06-01

    The renewable energy (RE) sector has grown exponentially in Malaysia with the introduction of the Feed-In-Tariff (FIT) by the Ministry of Energy, Green Technology and Water. Photovoltaic, biogas, biomass and mini hydro are among the renewable energy sources which offer a lucrative tariff to incite developers in taking the green technology route. In order to receive the FIT, a developer is required by the utility company to perform a power system analysis which will determine the technical feasibility of an RE interconnection to the utility company's existing grid system. There are a number of aspects which the analysis looks at, the most important being the load flow and fault levels in the network after the introduction of an RE source. The analysis is done by modelling the utility company's existing network and simulating the network with the interconnection of an RE source. The results are then compared to the values before an interconnection is made as well as ensuring the voltage rise or the increase in fault levels do not violate any pre-existing regulations set by the utility company. This paper will delve into the mechanics of performing a load flow analysis and examining the results obtained.

  13. Narita Target Heart Rate Equation Underestimates the Predicted Adequate Exercise Level in Sedentary Young Boys

    PubMed Central

    Siahkouhian, Marefat; Khodadadi, Davar

    2013-01-01

    Purpose Optimal training intensity and the adequate exercise level for physical fitness is one of the most important interests of coaches and sports physiologists. The aim of this study was to investigate the validity of the Narita et al target heart rate equation for the adequate exercise training level in sedentary young boys. Methods Forty two sedentary young boys (19.07±1.16 years) undertook a blood lactate transition threshold maximal treadmill test to volitional exhaustion with continuous respiratory gas measurements according to the Craig method. The anaerobic threshold (AT) of the participants then was calculated using the Narita target heart rate equation. Results Hopkin's spreadsheet to obtain confidence limit and the chance of the true difference between gas measurements and Narita target heart rate equation revealed that the Narita equation most likely underestimates the measured anaerobic threshold in sedentary young boys (168.76±15 vs. 130.08±14.36) (Difference ±90% confidence limit: 38.1±18). Intraclass correlation coefficient (ICC) showed a poor agreement between the criterion method and Narita equation (ICC= 0.03). Conclusion According to the results, the Narita equation underestimates the measured AT. It seems that the Narita equation is a good predictor of aerobic not AT which can be investigated in the future studies. PMID:24427475

  14. Studies of acoustic-electric feed-throughs for power transmission through structures

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart; Doty, Benjamin; Badescu, Mircea; Bao, Xiaoqi; Bar-Cohen, Yoseph; Aldrich, Jack; Chang, Zensheu

    2006-01-01

    There are numerous engineering design problems where the use of wires to transfer power and communicate data thru the walls of a structure is prohibitive or significantly difficult that it may require a complex design. Using physical feedthroughs in such systems may make them susceptible to leakage of chemicals or gasses, loss of pressure or vacuum, as well as difficulties in providing adequate thermal or electrical insulation. Moreover, feeding wires thru a wall of a structure reduces the strength of the structure and makes the structure prone to cracking due to fatigue that can result from cyclic loading and stress concentrations. One area that has already been identified to require a wireless alternative to electrical feedthroughs is the container of the Mars Sample Return Mission, which will need wireless sensors to sense a pressure leak and to avoid potential contamination. The idea of using elastic or acoustic waves to transfer power was suggested recently by [Y. Hu, et al., July 2003]. This system allows for the avoidance of cabling or wiring. The technology is applicable to the transfer of power for actuation, sensing and other tasks inside any sealed container or vacuum/pressure vessel. An alternative approach to the modeling presented previously [Sherrit et a., 2005] used network analysis to solve the same problem in a clear and expandable manner. Experimental tests on three different designs of these devices were performed. The three designs used different methods of coupling the piezoelectric element to the wall. In the first test the piezoelectric material was bolted using a backing structure. In the second test the piezoelectric was clamped after the application of grease and finally the piezoelectric element was attached using a conductive epoxy. The mechanical clamp with grease produced the highest measured efficiency of 53% however this design was the least practical from a fabrication viewpoint. The power transfer efficiency of conductive epoxy

  15. Design study for a gound microwave power transmission system for use with a high-altitude powered platform

    NASA Technical Reports Server (NTRS)

    Brown, W. C.

    1983-01-01

    The conceptual design of a ground-based microwave power transmission system is described. This system is intended to supply electrical power via an air link to a high-altitude (21 km) powered platform. The platform must be equipped with the required instrumentation (RECTENNA) to convert the RF energy to dc power.

  16. Study of secondary emission properties of materials used for high power RF components in space

    NASA Astrophysics Data System (ADS)

    Galan, L.; Moranti, C.; Rueda, F.; Sanz, J. M.

    1988-03-01

    Secondary electron emission (SEE) properties of materials used for high power waveguide components in space, particularly on surfaces for space hardware were studied, including Alodine surfaces before and after power conditioning. Surface treatments to aid multipactor suppression for these materials, including methods for surface protection and handling, were examined. If only true SEE is considered, Alodine coatings have better characteristics than TiN, TiC, Cr2O3, and C. The rugosity of Alodine may explain its good properties. No clear correlation between SEE characteristic values and multipactor threshold power is found; smaller SEE is not determinant for obtaining higher multipactor threshold power.

  17. Power and public participation in a hazardous waste dispute: a community case study.

    PubMed

    Culley, Marci R; Hughey, Joseph

    2008-03-01

    Qualitative case study findings are presented. We examined whether public participation in a hazardous waste dispute manifested in ways consistent with theories of social power; particularly whether participatory processes or participants' experiences of them were consistent with the three-dimensional view of power (Gaventa, Power and powerlessness: quiescence and rebellion in an appalacian valley, 1980; Lukes, Power: A radical view, 1974; Parenti, Power and the powerless, 1978). Findings from four data sources collected over 3 years revealed that participatory processes manifested in ways consistent with theories of power, and participants' experiences reflected this. Results illustrated how participation was limited and how citizen influence could be manipulated via control of resources, barriers to participation, agenda setting, and shaping conceptions about what participation was possible. Implications for community research and policy related to participation in hazardous waste disputes are discussed.

  18. Wind tunnel study of the power output spectrum in a micro wind farm

    NASA Astrophysics Data System (ADS)

    Bossuyt, Juliaan; Howland, Michael F.; Meneveau, Charles; Meyers, Johan

    2016-09-01

    Instrumented small-scale porous disk models are used to study the spectrum of a surrogate for the power output in a micro wind farm with 100 models of wind turbines. The power spectra of individual porous disk models in the first row of the wind farm show the expected -5/3 power law at higher frequencies. Downstream models measure an increased variance due to wake effects. Conversely, the power spectrum of the sum of the power over the entire wind farm shows a peak at the turbine-to-turbine travel frequency between the model turbines, and a near -5/3 power law region at a much wider range of lower frequencies, confirming previous LES results. Comparison with the spectrum that would result when assuming that the signals are uncorrelated, highlights the strong effects of correlations and anti-correlations in the fluctuations at various frequencies.

  19. Power and trust in organizational relations: an empirical study in Turkish public hospitals.

    PubMed

    Bozaykut, Tuba; Gurbuz, F Gulruh

    2015-01-01

    Given the salience of the interplay between trust and power relations in organizational settings, this paper examines the perceptions of social power and its effects on trust in supervisors within the context of public hospitals. Following the theoretical background from which the study model is developed, the recent situation of hospitals within Turkish healthcare system is discussed to further elucidate the working conditions of physicians. Sample data were collected employing a structured questionnaire that was distributed to physicians working at seven different public hospitals. The statistical analyses indicate that perceptions of supervisors' social power affect subordinates' trust in supervisors. Although coercive power is found to have the greatest impact on trust in supervisors, the influence of the power base is weak. In addition, the results show that perceptions of social power differ between genders. However, the results do not support any of the hypotheses regarding the relations between trust in supervisors and the examined demographic variables.

  20. Power to Detect Differences between Alternative Treatments in Comparative Psychotherapy Outcome Research.

    ERIC Educational Resources Information Center

    Kazdin, Alan E.; Bass, Debra

    1989-01-01

    Drew 85 outcome studies from 9 journals from 1984 through 1986. Examined data in each article to provide estimates of effect sizes and to evaluate statistical power at posttreatment and follow-up. Findings indicated that power of studies to detect differences between treatment and no treatment was generally quite adequate given relatively large…

  1. A Study of Power and Individualism in Virtual Teams: Trends, Challenges, and Solutions

    ERIC Educational Resources Information Center

    Jablonski, Deirdre

    2013-01-01

    This study investigated the relationship between cultural values and effectiveness of virtual team processes. In order to render an acceptable degree of comparison, four specific team outcomes of virtual team effectiveness were aligned on Hofstede's cultural dimensions of power distance and individualism. The lack of awareness of how power and…

  2. Maturation of EEG Power Spectra in Early Adolescence: A Longitudinal Study

    ERIC Educational Resources Information Center

    Cragg, Lucy; Kovacevic, Natasa; McIntosh, Anthony Randal; Poulsen, Catherine; Martinu, Kristina; Leonard, Gabriel; Paus, Tomas

    2011-01-01

    This study investigated the fine-grained development of the EEG power spectra in early adolescence, and the extent to which it is reflected in changes in peak frequency. It also sought to determine whether sex differences in the EEG power spectra reflect differential patterns of maturation. A group of 56 adolescents were tested at age 10 years and…

  3. Mentoring Support and Power: A Three Year Predictive Field Study on Protege Networking and Career Success

    ERIC Educational Resources Information Center

    Blickle, Gerhard; Witzki, Alexander H.; Schneider, Paula B.

    2009-01-01

    Career success of early employees was analyzed from a power perspective and a developmental network perspective. In a predictive field study with 112 employees mentoring support and mentors' power were assessed in the first wave, employees' networking was assessed after two years, and career success (i.e. income and hierarchical position) and…

  4. Solar power satellite system definition study. Volume 7, phase 1: SPS and rectenna systems analyses

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A systems definition study of the solar power satellite systems is presented. The design and power distribution of the rectenna system is discussed. The communication subsystem and thermal control characteristics are described and a failure analysis performed on the systems is reported.

  5. Solar power satellite system definition study. Volume 1, phase 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A systems definition study of the solar satellite system (SPS) is presented. The technical feasibility of solar power satellites based on forecasts of technical capability in the various applicable technologies is assessed. The performance, cost, operational characteristics, reliability, and the suitability of SPS's as power generators for typical commercial electricity grids are discussed. The uncertainties inherent in the system characteristics forecasts are assessed.

  6. Research Plan for Study of Biological and Ecological Effects of the Solar Power Satellite Transmission System

    NASA Technical Reports Server (NTRS)

    Newsom, B. D.

    1978-01-01

    A programmatic research plan for a three year study is presented to generate knowledge on effects of the continuous wave 2.45 GHz microwave power transmission that the Solar Power Satellite might have on biological and ecological elements, within and around the rectenna receiving site.

  7. Solar power satellite system definition study. Volume 2, phase 1: Systems analyses tradeoffs.

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A systems definition study of the solar power satellite system is presented. The satellite solar energy conversion and microwave power transmission systems are discussed. Space construction and support systems are examined including a series construction and equipment characteristics analysis. Space transportation for the satellite and the ground receiving station are assessed.

  8. Powerful Social Studies Teaching with Poetry and Primary Sources

    ERIC Educational Resources Information Center

    Sell, Corey Ranshaw; Griffin, Krista

    2017-01-01

    Given the current marginalization of the social studies within elementary classrooms it is vital that elementary educators seek integrative techniques that promote the social studies. This article explores one such example of integration taught by the authors within an elementary classroom. The three-day lesson taught to fifth-grade students aimed…

  9. White Lies: A Critical Race Study of Power and Privilege

    ERIC Educational Resources Information Center

    Brainard, Patricia Jones

    2009-01-01

    This was a phenomenological study of racial privilege as experienced by White people who have struggled to become more racially aware and socially active in dismantling racism and White privilege. The primary conceptual framework for this study was Critical Race Theory with Transformative Learning theory and Racial Identity Development as…

  10. AEGIS: A MULTIWAVELENGTH STUDY OF SPITZER POWER-LAW GALAXIES

    SciTech Connect

    Park, S. Q.; Barmby, P.; Willner, S. P.; Ashby, M. L. N.; Fazio, G. G.; Georgakakis, A.; Ivison, R. J.; Konidaris, N. P.; Rosario, D. J.; Nandra, K.

    2010-07-10

    This paper analyzes a sample of 489 Spitzer/Infrared Array Camera (IRAC) sources in the Extended Groth Strip (EGS), whose spectral energy distributions fit a red power law (PL) from 3.6 to 8.0 {mu}m. The median redshift for sources with known redshifts is (z) = 1.6. Though all or nearly all of the sample galaxies are likely to be active galactic nuclei (AGNs), only 33% were detected in the EGS X-ray survey (AEGIS-X) using 200 ks Chandra observations. The detected sources are X-ray luminous with L {sub X}>10{sup 43} erg s{sup -1} and moderately to heavily obscured with N {sub H}>10{sup 22} cm{sup -2}. Stacking the X-ray-undetected sample members yields a statistically significant X-ray signal, suggesting that they are on average more distant or more obscured than sources with X-ray detections. The ratio of X-ray to mid-infrared fluxes suggests that a substantial fraction of the sources undetected in X-rays are obscured at the Compton-thick level, in contrast to the X-ray-detected sources, all of which appear to be Compton thin. For the X-ray-detected PL sources with redshifts, an X-ray luminosity L {sub X} {approx} 10{sup 44} erg s{sup -1} marks a transition between low-luminosity, blue sources dominated by the host galaxy to high-luminosity, red PL sources dominated by nuclear activity. X-ray-to-optical ratios, infrared variability, and 24 {mu}m properties of the sample are consistent with the identification of infrared PL sources as active nuclei, but a rough estimate is that only 22% of AGNs are selected by the PL criteria. Comparison of the PL selection technique and various IRAC color criteria for identifying AGNs confirms that high-redshift samples selected via simple IRAC colors may be heavily contaminated by starlight-dominated objects.

  11. A Simulation Study to Assess the Effect of the Number of Response Categories on the Power of Ordinal Logistic Regression for Differential Item Functioning Analysis in Rating Scales

    PubMed Central

    Allahyari, Elahe; Jafari, Peyman; Bagheri, Zahra

    2016-01-01

    Objective. The present study uses simulated data to find what the optimal number of response categories is to achieve adequate power in ordinal logistic regression (OLR) model for differential item functioning (DIF) analysis in psychometric research. Methods. A hypothetical ten-item quality of life scale with three, four, and five response categories was simulated. The power and type I error rates of OLR model for detecting uniform DIF were investigated under different combinations of ability distribution (θ), sample size, sample size ratio, and the magnitude of uniform DIF across reference and focal groups. Results. When θ was distributed identically in the reference and focal groups, increasing the number of response categories from 3 to 5 resulted in an increase of approximately 8% in power of OLR model for detecting uniform DIF. The power of OLR was less than 0.36 when ability distribution in the reference and focal groups was highly skewed to the left and right, respectively. Conclusions. The clearest conclusion from this research is that the minimum number of response categories for DIF analysis using OLR is five. However, the impact of the number of response categories in detecting DIF was lower than might be expected. PMID:27403207

  12. Satellite Power System (SPS) concept definition study (exhibit C)

    NASA Technical Reports Server (NTRS)

    Haley, G. M.

    1979-01-01

    The major outputs of the study are the constructability studies which resulted in the definition of the concepts for satellite, rectenna, and satellite construction base construction. Transportation analyses resulted in definition of heavy-lift launch vehicle, electric orbit transfer vehicle, personnel orbit transfer vehicle, and intra-orbit transfer vehicle as well as overall operations related to transportation systems. The experiment/verification program definition resulted in the definition of elements for the Ground-Based Experimental Research and Key Technology plans. These studies also resulted in conceptual approaches for early space technology verification. The cost analysis defined the overall program and cost data for all program elements and phases.

  13. Matching occupation and self: does matching theory adequately model children's thinking?

    PubMed

    Watson, Mark; McMahon, Mary

    2004-10-01

    The present exploratory-descriptive cross-national study focused on the career development of 11- to 14-yr.-old children, in particular whether they can match their personal characteristics with their occupational aspirations. Further, the study explored whether their matching may be explained in terms of a fit between person and environment using Holland's theory as an example. Participants included 511 South African and 372 Australian children. Findings relate to two items of the Revised Career Awareness Survey that require children to relate personal-social knowledge to their favorite occupation. Data were analyzed in three stages using descriptive statistics, i.e., mean scores, frequencies, and percentage agreement. The study indicated that children perceived their personal characteristics to be related to their occupational aspirations. However, how this matching takes place is not adequately accounted for in terms of a career theory such as that of Holland.

  14. Mirror, Mirrors on the Wall, Who Is the Most Powerful of All? A Self-Study Analysis of Power Relationships in Science Methods Courses

    ERIC Educational Resources Information Center

    Moscovici, Hedy

    2007-01-01

    This study explored the dynamics of power relationships in secondary science methods courses taught at an urban university in Southern California for credential candidates. Data collection extended over 10 academic semesters. Employing frameworks of power, self-study, and critical pedagogy, the study analyzes the multifaceted and intricate roads…

  15. Duration of Pulmonary Tuberculosis Infectiousness under Adequate Therapy, as Assessed Using Induced Sputum Samples

    PubMed Central

    Ko, Yousang; Shin, Jeong Hwan; Lee, Hyun-Kyung; Lee, Young Seok; Lee, Suh-Young; Park, So Young; Mo, Eun-Kyung; Kim, Changhwan

    2017-01-01

    Background A sputum culture is the most reliable indicator of the infectiousness of pulmonary tuberculosis (PTB); however, a spontaneous sputum specimen may not be suitable. The aim of this study was to evaluate the infectious period in patients with non–drug-resistant (DR) PTB receiving adequate standard chemotherapy, using induced sputum (IS) specimens. Methods We evaluated the duration of infectiousness of PTB using a retrospective cohort design. Results Among the 35 patients with PTB, 22 were smear-positive. The rates of IS culture positivity from baseline to the sixth week of anti-tuberculosis medication in the smear-positive PTB group were 100%, 100%, 91%, 73%, 36%, and 18%, respectively. For smear-positive PTB cases, the median time of conversion to culture negativity was 35.0 days (range, 28.0–42.0 days). In the smear-negative PTB group (n=13), the weekly rates of positive IS culture were 100%, 77%, 39%, 8%, 0%, and 0%, respectively, and the median time to conversion to culture-negative was 21.0 days (range, 17.5–28.0 days). Conclusion The infectiousness of PTB, under adequate therapy, may persist longer than previously reported, even in patients with non-DR PTB. PMID:28119744

  16. Advanced Fusion Power Plant Studies. Annual Report for 1999

    SciTech Connect

    Chan, V.S.; Chu, M.S.; Greenfield, C.M.; Kinsey, J.E.; et al.

    2000-01-01

    Significant progress in physics understanding of the reversed shear advanced tokamak regime has been made since the last ARIES-RS study was completed in 1996. The 1999 study aimed at updating the physics design of ARIES-RS, which has been renamed ARIES-AT, using the improved understanding achieved in the last few years. The new study focused on: Improvement of beta-limit stability calculations to include important non-ideal effects such as resistive wall modes and neo-classical tearing modes; Use of physics based transport model for internal transport barrier (ITB) formation and sustainment; Comparison of current drive and rotational flow drive using fast wave, electron cyclotron wave and neutral particle beam; Improvement in heat and particle control; Integrated modeling of the optimized scenario with self-consistent current and transport profiles to study the robustness of the bootstrap alignment, ITB sustainment, and stable path to high beta and high bootstrap fraction operation.

  17. New FASST Study on Students and Solar Power Satellites.

    ERIC Educational Resources Information Center

    David, Leonard

    1979-01-01

    Discusses the recommendations of the Forum for the Advancement of Students in Science and Technology (FASST) study which stressed identifying methods to increase student participation in the discussion of the potential benefits and problems of beaming energy from space. (MA)

  18. Integrated power sector efficiency analysis: A case study of Costa Rica

    SciTech Connect

    Waddle, D.B.; MacDonald, J.M.

    1990-03-01

    In an effort to analyze and document the potential for power sector efficiency improvements from generation to end-use, the Agency for International Development and the Government of Costa Rica are jointly conducting an integrated power sector efficiency analysis. Potential for energy and cost savings in power plants, transmission and distribution, and demand-side management programs are being evaluated. The product of this study will be an integrated investment plan for the Instituto Costarricense de Electricidad, incorporating both supply and demand side investment options. This paper presents the methodology employed in the study, as well as preliminary estimates of the results of the study. 14 refs., 2 figs., 5 tabs.

  19. Fundamental studies in cryogenic cooling of power electronics

    NASA Astrophysics Data System (ADS)

    Chow, L. C.; Sehmbey, M. S.; Hahm, O. J.; Chui, C. J.

    1994-09-01

    This study details the results from experiments conducted to study the heat transfer characteristics during liquid nitrogen spray cooling and pool boiling from a heater array. Four different nozzles at various pressures were used to study the variation in spray cooling heat transfer at liquid nitrogen temperature. Effect of nozzle and flow rate on the critical heat flux and the heat transfer coefficient are presented. This study also provides empirical correlations for the spray cooling characteristics. The critical heat flux and the heat transfer coefficient have been correlated using nondimensional numbers. The study also shows the importance of surface roughness for spray cooling with liquid nitrogen. The rougher surfaces were shown to have significantly higher heat transfer rates and similar critical heat fluxes occurring at lower temperatures. The results from experiments conducted to study the pool boiling heat transfer from a vertical array with flush mounted heat sources are also presented. The lower heaters were found to enhance the heat transfer from the upper heaters due to bubble pumped convection.

  20. Simulation of Some of the Power Electronics Case Studies in Matlab Simpowsystem Toolbox

    NASA Astrophysics Data System (ADS)

    Alasooly, Hedaya; Redha, Mohammed

    2010-06-01

    Matlab SimPowerSystems is a modern design tool that allows scientists and engineers to rapidly and easily build models that simulate power systems. Not only can you draw the circuit topology rapidly, but your analysis of the circuit can include its interactions with mechanical, thermal, control, and other disciplines. The paper covers some case studies that provide detailed, realistic examples of how to use SimPowerSystems in power system analysis. The following types of studies is coverted on the paper: 1. Thyristor-Based Static Var Compensator: Study the steady-state and dynamic performance of a static var compensator (SVC) on a transmission system. 2. Transient Stability of a Power System with SVC and PSS: Study of the application of static var compensator (SVC) and power system stabilizers (PSS) to improve transient stability and power oscillation damping of the system. 3. GTO-Based STATCOM: Study the steady-state and dynamic performance of a static synchronous compensator (STATCOM) on a transmission system. 4. Control of load flow using UPFC: Study the steady-state and dynamic performance of a unified power flow controller (UPFC). 5. Chopper-Fed DC Motor Drive: Study of a DC motor drive with armature voltage controlled by a GTO thyristor chopper. 6. VSC-Based HVDC Link: Modeling of a forced-commutated Voltage-Sourced Converter high-voltage direct current (VSC-HVDC) transmission link. 7. Three-Phase Network with Electrical Machines: Simulation of a three-phase power system containing electrical machines and other three-phase models. 8. Variable-Frequency Induction Motor Drive: Study of a PWM inverter-driven variable-frequency AC induction motor in variable-voltage, variable-speed operation.

  1. Conceptual Trade Study of General Purpose Heat Source Powered Stirling Converter Configurations

    NASA Technical Reports Server (NTRS)

    Turpin, J. B.

    2007-01-01

    This Technical Manual describes a parametric study of general purpose heat source (GPHS) powered Stirling converter configurations. This study was performed in support of MSFC s efforts to establish the capability to perform non-nuclear system level testing and integration of radioisotope power systems. Six different GPHS stack configurations at a total of three different power levels (80, 250, and 500 W(sub e) were analyzed. The thermal profiles of the integrated GPHS modules (for each configuration) were calculated to determine maximum temperatures for comparison to allowable material limits. Temperature profiles for off-nominal power conditions were also assessed in order to better understand how power demands from the Stirling engine impact the performance of a given configuration.

  2. Study of HF behaviour of railway power substation in reduced scale

    NASA Astrophysics Data System (ADS)

    Ouaddi, H.; Baranowski, S.; Nottet, G.; Demoulin, B.; Koné, L.

    2011-03-01

    The study presented in this paper is a first step of an EMC (Electromagnetic Compatibility) analysis of the behaviour of a railway power substation at high frequency. Before on site intensive experimentation, the approach is performed with a reduced scale model. The mock-up of the substation is powered by a 220 V three-phase voltage supplied by a 15 kV A power transformer, a rectifier and loads. The study consists in designing an equivalent electrical circuit of power transformer in high frequency, available over a large panel of loads. The model of power transformer was deduced from measurements in frequency domain within the range 40 Hz to 30 MHz.

  3. Satellite Power Systems (SPS) concept definition study (exhibit C)

    NASA Technical Reports Server (NTRS)

    Hanley, G. M.

    1978-01-01

    A coplanar satellite conceptual approach was defined. This effort included several trade studies related to satellite design and also construction approaches for this satellite. A transportation system, consistent with this concept, was also studied, including an electric orbit transfer vehicle and a parallel-burn heavy lift launch vehicle. Work on a solid state microwave concept continued and several alternative approaches were evaluated. Computer determination of an optimized transistor and circuit design was also continued. Experiment/verification planning resulted in the development of a total solar array and microwave technology development plan, as well as definition of near-term research to evaluate key technology issues.

  4. Study of thermal control systems for orbiting power systems. Materials experiment carrier thermal control system study

    NASA Technical Reports Server (NTRS)

    Fleming, M. L.

    1980-01-01

    Four possible arrangements of the materials experiment carrier (MEC) and power system (PS) thermal control loops were defined which would provide one kW of heat rejection for each kW of power to the MEC payload. These arrangements were compared to the baseline reference concept which provides only 16 kW heat rejection to show the cost of obtaining symmetry in terms of dollars, weight, complexity, growth potential, ease of integration, technology and total launch weight. The results of these comparisons was that the concept which splits the PS thermal control loop into two systems, one to reject PS waste heat and one payload waste heat, appeared favorable. The fluid selection study resulted in recommendation of FC72 as the MEC heat transport fluid based on the thermal and physical characteristics. The coatings reviewed indicated anodized and alodine treated aluminum surfaces or silver teflon are the best choices for the MEC vehicle where durability is an important factor. For high temperature radiators silver teflon or zinc orthotitanate are recommended choices.

  5. Brayton Power Conversion System Study to Advance Technology Readiness for Nuclear Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Allen, Bog; Delventhal, Rex; Frye, Patrick

    2004-01-01

    Recently, there has been significant interest within the aerospace community to develop space based nuclear power conversion technologies especially for exploring the outer planets of our solar system where the solar energy density is very low. To investigate these technologies NASA awarded several contracts under Project Prometheus, the Nuclear Systems Program. The studies described in this paper were performed under one of those contracts, which was to investigate the use of a nuclear power conversion system based on the closed Brayton cycle (CBC).The investigation performed included BPCS (Brayton Power Conversion System) trade studies to minimize system weight and radiator area and advance the state of the art of BPCS technology. The primary requirements for studies were a power level of 100 kWe (to the PPU), a low overall power system mass and a lifetime of 15 years (10 years full power). For the radiation environment, the system was to be capable of operation in the generic space environment and withstand the extreme environments surrounding Jupiter. The studies defined a BPCS design traceable to NEP (Nuclear Electric Propulsion) requirements and suitable for future missions with a sound technology plan for technology readiness level (TRL) advancement identified. The studies assumed a turbine inlet temperature approx. 100 C above the current the state of the art capabilities with materials issues and related development tasks identified. Analyses and evaluations of six different HRS (heat rejection system) designs and three primary power management and distribution (PMAD) configurations will be discussed in the paper.

  6. Brayton Power Conversion System Study to Advance Technology Readiness for Nuclear Electric Propulsion - Phase I

    SciTech Connect

    Frye, Patrick E.; Allen, Robert; Delventhal, Rex

    2005-02-06

    To investigate and mature space based nuclear power conversion technologies NASA awarded several contracts under Prometheus, the Nuclear Systems Program. The studies described in this paper were performed under one of those contracts, which was to investigate the use of a nuclear power conversion system based on the closed Brayton cycle (CBC). The conceptual design effort performed included BPCS (Brayton power conversion system) trade studies to minimize system weight and radiator area and advance the state of the art of BPCS technology. The primary requirements for studies were a power level of 100 kWe (to the PPU), a low overall power system mass (with a target of less than 3000 kg), and a lifetime of 15 years (10 years full power). For the radiation environment, the system was to operate in the generic space environment and withstand the extreme environments within the Jovian system. The studies defined a BPCS design traceable to NBP (Nuclear Electric Propulsion) requirements and suitable for future potential missions with a sound technology plan for TRL (Technical Readiness Level) advancement identified. The studies assumed a turbine inlet temperature {approx} 100C above the current the state of the art capabilities with materials issues identified and an approach for resolution developed. Analyses and evaluations of six HRS (heat rejection subsystem) concepts and PMAD (Power Management and Distribution) architecture trades will be discussed in the paper.

  7. Laboratory of plasma studies. Papers on high power particle beams

    SciTech Connect

    Not Available

    1990-01-01

    This book contains paper on Exploding metal film active anode sources experiments on the Lion extractor Ion Diode; Long conductor time plasma opening switch experiments; and Focusing studies of an applied B{sub r} extraction diode on the Lion accelerator.

  8. The Powers and Pitfalls of Algorithmic Knowledge: A Case Study

    ERIC Educational Resources Information Center

    Ebby, Caroline Brayer

    2005-01-01

    This study examines one child's use of computational procedures over a period of 3 years in an urban elementary school where teachers were using a standards-based curriculum. From a sociocultural perspective, the use of standard algorithms to solve mathematical problems is viewed as a cultural tool that both enables and constrains particular…

  9. Partner Power: A Study of Two Distance Education Consortia

    ERIC Educational Resources Information Center

    Pidduck, Anne Banks; Carey, Tom

    2006-01-01

    This research reports findings from a study which explored the process and criteria of partner selection--how and why partners are chosen--for two distance education consortia. The researchers reviewed recent literature on partnerships and partner selection. Two Canada-wide distance education consortia were identified as large-scale case studies…

  10. A super powerful method for genome wide association study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genome-Wide Association Studies shed light on the identification of genes underlying human diseases and agriculturally important traits. This potential has been shadowed by false positive findings. The Mixed Linear Model (MLM) method is flexible enough to simultaneously incorporate population struct...

  11. Storypath: Powerful Social Studies Instruction in the Primary Grades.

    ERIC Educational Resources Information Center

    Fulwiler, Betsy Rupp; McGuire, Margit E.

    1997-01-01

    Recommends using the Storypath method for introducing social studies concepts into the primary grades. Storypath introduces children to an imaginary environment (a neighborhood) and, working in teams, students provide details and people. Eventually they face a problem (litter), then bring the story and the problem to some kind of resolution. (MJP)

  12. People and Power. A Study of Crisis in Secondary Schools.

    ERIC Educational Resources Information Center

    Wittes, Simon

    The study reported here is based on the belief that the social discontent that is frequently in evidence stems in part from individuals being trapped in dehumanizing organizational mazes which apply bureaucratic rules in an attempt to control human behavior in light of organizational needs. This investigation, therefore, set out to discover the…

  13. Exploring Powered Wheelchair Users and Their Caregivers’ Perspectives on Potential Intelligent Power Wheelchair Use: A Qualitative Study

    PubMed Central

    Kairy, Dahlia; Rushton, Paula W.; Archambault, Philippe; Pituch, Evelina; Torkia, Caryne; El Fathi, Anas; Stone, Paula; Routhier, François; Forget, Robert; Demers, Louise; Pineau, Joelle; Gourdeau, Richard

    2014-01-01

    Power wheelchairs (PWCs) can have a positive impact on user well-being, self-esteem, pain, activity and participation. Newly developed intelligent power wheelchairs (IPWs), allowing autonomous or collaboratively-controlled navigation, could enhance mobility of individuals not able to use, or having difficulty using, standard PWCs. The objective of this study was to explore the perspectives of PWC users (PWUs) and their caregivers regarding if and how IPWs could impact on current challenges faced by PWUs, as well as inform current development of IPWs. A qualitative exploratory study using individual interviews was conducted with PWUs (n = 12) and caregivers (n = 4). A semi-structured interview guide and video were used to facilitate informed discussion regarding IPWs. Thematic analysis revealed three main themes: (1) “challenging situations that may be overcome by an IPW” described how the IPW features of obstacle avoidance, path following, and target following could alleviate PWUs’ identified mobility difficulties; (2) “cautious optimism concerning IPW use revealed participants” addresses concerns regarding using an IPW as well as technological suggestions; (3) “defining the potential IPW user” revealed characteristics of PWUs that would benefit from IPW use. Findings indicate how IPW use may help overcome PWC difficulties and confirm the importance of user input in the ongoing development of IPWs. PMID:24566051

  14. Understanding Unresponsiveness to Tier 2 Reading Intervention: Exploring the Classification and Profiles of Adequate and Inadequate Responders in First Grade

    ERIC Educational Resources Information Center

    Toste, Jessica R.; Compton, Donald L.; Fuchs, Douglas; Fuchs, Lynn S.; Gilbert, Jennifer K.; Cho, Eunsoo; Barquero, Laura A.; Bouton, Bobette D.

    2014-01-01

    The purpose of the current study was to examine academic and cognitive profiles of first graders who responded adequately and inadequately to intensive small-group reading intervention (Tier 2), as well as assess how these profiles differ based on the criteria used for classification of unresponsiveness. Nonresponders were identified using two…

  15. The Human Right to Adequate Housing: A Tool for Promoting and Protecting Individual and Community Health

    PubMed Central

    Thiele, Bret

    2002-01-01

    The human right to adequate housing is enshrined in international law. The right to adequate housing can be traced to the Universal Declaration of Human Rights, which was unanimously adopted by the world community in 1948. Since that time, the right to adequate housing has been reaffirmed on numerous occasions and further defined and elaborated. A key component of this right is habitability of housing, which should comply with health and safety standards. Therefore, the right to adequate housing provides an additional tool for advocates and others interested in promoting healthful housing and living conditions and thereby protecting individual and community health. PMID:11988432

  16. The Effects of Type I Error Rate and Power of the ANCOVA "F" Test and Selected Alternatives under Nonnormality and Variance Heterogeneity.

    ERIC Educational Resources Information Center

    Rheinheimer, David C.; Penfield, Douglas A.

    2001-01-01

    Studied, through Monte Carlo simulation, the conditions for which analysis of covariance (ANCOVA) does not maintain adequate Type I error rates and power and evaluated some alternative tests. Discusses differences in ANCOVA robustness for balanced and unbalanced designs. (SLD)

  17. Solar power satellite system definition study. Volume 1, phase 2: Executive summary

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A review of solar energy conversion and utilization is presented. The solar power satellite system is then described. Overall system definition and integration is discussed. Principal reference system study accomplishments and conclusions are presented.

  18. Development of a single-phase harmonic power flow program to study the 20 kHz AC power system for large spacecraft

    NASA Technical Reports Server (NTRS)

    Kraft, L. Alan; Kankam, M. David

    1991-01-01

    The development of software is described to aid in design and analysis of AC power systems for large spacecraft. The algorithm is an important version of harmonic power flow program, HARMFLO, used for the study of AC power quality. The new program is applicable to three-phase systems typified by terrestrial power systems, and single-phase systems characteristic of space power systems. The modified HARMFLO accommodates system operating frequencies ranging from terrestrial 60 Hz to and beyond aerospace 20 kHz, and can handle both source and load-end harmonic distortions. Comparison of simulation and test results of a representative spacecraft power system shows a satisfactory correlation. Recommendations are made for the direction of future improvements to the software, to enhance its usefulness to power system designer and analysts.

  19. WMU Power Generation Study Task 2.0 Corn Cob Co-Combustion Study: Final Report

    SciTech Connect

    Folkedahl, Bruce

    2009-12-01

    Much attention has been focused on renewable energy use in large-scale utilities and very small scale distributed energy systems. However, there is little information available regarding renewable energy options for midscale municipal utilities. The Willmar Municipal Utilities Corn Cob-Coal Co-Combustion Project was initiated to investigate opportunities available for small to midscale municipal utilities to "go green". The overall goal of the Project was to understand the current t'enewable energy research and energy efficiency projects that are or have been implemented at both larger and smaller scale and determine the applicability to midscale municipal utilities. More specific objectives for Task 2.0 of this project were to determine the technical feasibility of co-combusting com cobs with coal in the existing WMU boiler, and to identify any regulatory issues that might need to be addressed if WMU were to obtain a significant portion of its heat from such co-combustion. This report addresses the issues as laid out in the study proposal. The study investigated the feasibility of and demonstrated the technical effectiveness of co-combusting corn cobs with coal in the Willmar Municipal Utilities stoker boiler steam generation power plant. The results of the WMU Co-Combustion Project will serve as a model for other midscale utilities who wish to use corn cobs to generate renewable electrical energy. As a result of the Co-Combustion Project, the WMU plans to upgrade their stoker boiler to accept whole corn cobs as well as other types of biomass, while still allowing the fuel delivery system to use 100% coal as needed. Benefits of co-combustion will include: energy security, reduced Hg and CO2 air emissions, improved ash chemistry, potential future carbon credit sales, an immediate positive effect on the local economy, and positive attention focused on the WMU and the City of Willmar. The first step in the study was to complete a feasibility analysis. The

  20. The hygroscopic power of amorphous cellulose: a modeling study.

    PubMed

    Mazeau, Karim

    2015-03-06

    The relationship between cellulose and water was studied by building dense amorphous cellulose models and subjecting them to increasing moisture contents. When starting from completely dry cellulose, the first diffused water molecules were essentially individualized and hydrogen bonded exclusively to the O6 and O2 hydroxyl groups of cellulose. Upon continued hydration increase, the hydroxyl at O3 and then the acetal oxygens of cellulose also started to attract the upcoming water molecules, which were no longer isolated. They progressively became aggregated, first into clusters and then at high hydration content, into continuous capillary channels. A benefit of this study was to allow predicting a number of physical parameters of amorphous cellulose and their variation under hydration. With some parameters, the calculated values matched rather well the experimental literature determinations. This was the case for the hydration dependence of Tg, the stereoselectivity of the cellulose oxygen atoms for water molecules, together with the diffusion coefficients of water into cellulose. An estimate of the hygro-expansion of amorphous cellulose was provided.

  1. Fundamental Materials Studies for Advanced High Power Microwave and Terahertz Vacuum Electronic Radiation Sources

    DTIC Science & Technology

    2014-12-10

    Models for Microstrip Computer-Aided Design,” in Microwave Symposium Digest , 1980 IEEE MTT-S International, 1980, p. 407. [2] B.B. Yang, S.L...AFRL-OSR-VA-TR-2014-0359 Fundamental Materials Studies for Advanced High Power Microwave and Terahertz John Booske UNIVERSITY OF WISCONSIN SYSTEM...12-2014 Final Technical Performance Report October 1, 2011 - September 30, 2014 Fundamental Materials Studies for Advanced High Power Microwave and

  2. A digital computer simulation and study of a direct-energy-transfer power-conditioning system

    NASA Technical Reports Server (NTRS)

    Burns, W. W., III; Owen, H. A., Jr.; Wilson, T. G.; Rodriguez, G. E.; Paulkovich, J.

    1974-01-01

    A digital computer simulation technique, which can be used to study such composite power-conditioning systems, was applied to a spacecraft direct-energy-transfer power-processing system. The results obtained duplicate actual system performance with considerable accuracy. The validity of the approach and its usefulness in studying various aspects of system performance such as steady-state characteristics and transient responses to severely varying operating conditions are demonstrated experimentally.

  3. Capacitor Characterization Study for a High Power High Frequency Converter Application (PREPRINT)

    DTIC Science & Technology

    2010-04-01

    Bixel, W.C. Lanter, B.Ray, “Evaluation of Fluorene Polyester Film Capacitors ”, CARTS USA-2010, 15-18 Mar 2010 New Orleans LA. 16 H. Kosai, S...AFRL-RZ-WP-TP-2010-2099 CAPACITOR CHARACTERIZATION STUDY FOR A HIGH POWER, HIGH FREQUENCY CONVERTER APPLICATION (PREPRINT) William Lanter...Paper Preprint 04 August 2009 – 01 April 2010 4. TITLE AND SUBTITLE CAPACITOR CHARACTERIZATION STUDY FOR A HIGH POWER, HIGH FREQUENCY CONVERTER

  4. Study terrestrial applications of solar cell powered systems

    NASA Technical Reports Server (NTRS)

    Ravin, J. W.

    1973-01-01

    Terrestrial applications of solar cells and design systems are considered for those applications that show the most promise for becoming practical and accepted by users within the next five years. The study includes the definition, categorization, evaluation and screening of the most attractive potential terrestrial applications for solar cells. Potential markets are initially grouped and categorized in a general sense and are weighted in priority by their business volume, present and future. From a categorized list including marine, transportation, security, communication, meteorological and others, 66 potential solar cell applications have been cataloged. A methodology was formulated to include the criteria for evaluation and screening. The evaluation process covers all parts and components of the complete system required for each application and gives consideration to all factors, such as engineering, economic, production, marketing and other factors that may have an influence on the acceptance of the system.

  5. Engineering calculations on microcomputers for power system studies

    SciTech Connect

    Shelby, L.; Albright, H.E.

    1982-07-01

    Microcomputers have in recent years become economical for any small business and/or individuals. With their ease of operation, high speed, flexibility, and low cost these units provide the engineer with an extremely valuable tool that enables him to perform the most complex engineering calculation and enhances his ability to make optimization studies of all types with ease. Typical computer systems highlighting the state of the art with recommended features for maximum utilization by engineers are described. Also discussed are programs for calculations such as short circuit, load flow, motor acceleration, voltage drop, sag and tension for overhead distribution, and others. Program development for the small computer is limited only by the resourcefulness and imagination of the user. It is expected that in time these units will become as common in the industry as the slide rule or the programmable calculator.

  6. Solar power satellite offshore rectenna study. Final report

    SciTech Connect

    Not Available

    1980-05-01

    Rice University, Brown and Root Development Inc., and Arthur D. Little Inc. have jointly conducted a feasibility study of an offshore rectenna serving the Boston/New York area. We found that an offshore rectenna is feasible and cost competitive with land rectennas but that the type of rectenna which is suitable for offshore use is quite different from that specified in the present reference system. We began by engineering the reference system rectenna to the offshore location. When we estimated costs for the resulting system we found that the cost was prohibitively high. We then searched for modifications to the design which would allow significant cost reduction. The result is a non-ground plane design which minimizes the weight and greatly reduces the number of costly support towers. This preferred design is an antenna array consisting of individually encapsulated dipoles with reflectors or yagis supported on feed wires. We find that such a 5 GW rectenna could be built at a 50 m water depth site to withstand hurricane, winter storm and icing conditions for a one time cost of $5.7 billion. Subsequent units would be about 1/3 less expensive. It is important to note that the east coast site chosen for this study represents an extreme case of severe environmental conditions. More benign and more shallow water sites would result in substantially lower costs. Secondary uses such as mariculture appear practical with only minor impact on the rectenna design. The potential advantages of an offshore rectenna such as no land requirements, removal of microwave radiation from populated areas and minimal impact on the local geopolitics argue strongly that further investigation of the offshore rectenna should be vigorously pursued.

  7. Downscaling Solar Power Output to 4-Seconds for Use in Integration Studies: Preprint

    SciTech Connect

    Hummon, M.; Weekley, A.; Searight, K.; Clark, K.

    2013-10-01

    High penetration renewable integration studies require solar power data with high spatial and temporal accuracy to quantify the impact of high frequency solar power ramps on the operation of the system. Our previous work concentrated on downscaling solar power from one hour to one minute by simulation. This method used clearness classifications to categorize temporal and spatial variability, and iterative methods to simulate intra-hour clearness variability. We determined that solar power ramp correlations between sites decrease with distance and the duration of the ramp, starting at around 0.6 for 30-minute ramps between sites that are less than 20 km apart. The sub-hour irradiance algorithm we developed has a noise floor that causes the correlations to approach ~0.005. Below one minute, the majority of the correlations of solar power ramps between sites less than 20 km apart are zero, and thus a new method to simulate intra-minute variability is needed. These intra-minute solar power ramps can be simulated using several methods, three of which we evaluate: a cubic spline fit to the one-minute solar power data; projection of the power spectral density toward the higher frequency domain; and average high frequency power spectral density from measured data. Each of these methods either under- or over-estimates the variability of intra-minute solar power ramps. We show that an optimized weighted linear sum of methods, dependent on the classification of temporal variability of the segment of one-minute solar power data, yields time series and ramp distributions similar to measured high-resolution solar irradiance data.

  8. Downscaling Solar Power Output to 4-Seconds for Use in Integration Studies (Presentation)

    SciTech Connect

    Hummon, M.; Weekley, A.; Searight, K.; Clark, K.

    2013-10-01

    High penetration renewable integration studies require solar power data with high spatial and temporal accuracy to quantify the impact of high frequency solar power ramps on the operation of the system. Our previous work concentrated on downscaling solar power from one hour to one minute by simulation. This method used clearness classifications to categorize temporal and spatial variability, and iterative methods to simulate intra-hour clearness variability. We determined that solar power ramp correlations between sites decrease with distance and the duration of the ramp, starting at around 0.6 for 30-minute ramps between sites that are less than 20 km apart. The sub-hour irradiance algorithm we developed has a noise floor that causes the correlations to approach ~0.005. Below one minute, the majority of the correlations of solar power ramps between sites less than 20 km apart are zero, and thus a new method to simulate intra-minute variability is needed. These intra-minute solar power ramps can be simulated using several methods, three of which we evaluate: a cubic spline fit to the one-minute solar power data; projection of the power spectral density toward the higher frequency domain; and average high frequency power spectral density from measured data. Each of these methods either under- or over-estimates the variability of intra-minute solar power ramps. We show that an optimized weighted linear sum of methods, dependent on the classification of temporal variability of the segment of one-minute solar power data, yields time series and ramp distributions similar to measured high-resolution solar irradiance data.

  9. Rotary ultrasonic machining of CFRP composites: a study on power consumption.

    PubMed

    Cong, W L; Pei, Z J; Deines, T W; Srivastava, Anil; Riley, L; Treadwell, C

    2012-12-01

    Carbon fiber reinforced plastic (CFRP) composites are very difficult to machine. A large number of holes need to be drilled in CFRP for many applications. Therefore, it is important to develop cost-effective drilling processes. CFRP has been drilled by rotary ultrasonic machining (RUM) successfully. The literature has reports about the effects of input variables on output variables (including cutting force, torque, surface roughness, tool wear, and workpiece delamination) in RUM of CFRP. However, there are no reports on power consumption in RUM of CFRP. This paper reports the first study on power consumption in RUM of CFRP. It reports an experimental investigation on effects of input variables (ultrasonic power, tool rotation speed, feedrate, and type of CFRP) on power consumption of each component (including ultrasonic power supply, spindle motor, coolant pump, and air compressor) and the entire RUM system.

  10. A feasibility study on the predictive emission monitoring system applied to the Hsinta power plant of Taiwan Power Company.

    PubMed

    Chien, T W; Chu, H; Hsu, W C; Tseng, T K; Hsu, C H; Chen, K Y

    2003-08-01

    The continuous emission monitoring system (CEMS) can monitor flue gas emissions continuously and instantaneously. However, it has the disadvantages of enormous cost, easily producing errors in sampling periods of bad weather, lagging response in variable ambient environments, and missing data in daily zero and span tests and maintenance. The concept of a predictive emission monitoring system (PEMS) is to use the operating parameters of combustion equipment through thermodynamic or statistical methods to construct a mathematic model that can predict emissions by a computer program. The goal of this study is to set up a PEMS in a gas-fired combined cycle power generation unit at the Hsinta station of Taiwan Power Co. The emissions to be monitored include nitrogen oxides (NOx) and oxygen (O2) in flue gas. The major variables of the predictive model were determined based on the combustion theory. The data of these variables then were analyzed to establish a regression model. From the regression results, the influences of these variables are discussed and the predicted values are compared with the CEMS data for accuracy. In addition, according to the cost information, the capital and operation and maintenance costs for a PEMS can be much lower than those for a CEMS.

  11. Gender, power, and intimate partner violence: a study on couples from rural Malawi.

    PubMed

    Conroy, Amy A

    2014-03-01

    Gender-based power imbalances are perhaps the most compelling underlying explanation for intimate partner violence (IPV) among women in sub-Saharan Africa. However, an overemphasis on female victimization results in an incomplete understanding of men's experiences as victims and the broader dyadic context in which violence occurs. This study examines the role of three domains of relationship power (power resources, processes, and outcomes) on sexual and physical IPV victimization in a unique sample of 466 young couples from Malawi. Two power resources were studied, namely, income and education level. Power processes were captured with a measure of couple communication and collaboration called unity. Power outcomes included a measure of relationship dominance (male dominated or female-dominated/egalitarian). Multilevel logistic regression using the Actor Partner Interpersonal Model framework was used to test whether respondent and partner data were predictive of IPV. The findings show that unity and male dominance were salient power factors that influenced young people's risk for sexual IPV. Unity had a stronger protective effect on sexual IPV for women than for men. Involvement in a male-dominated relationship increased the risk of sexual IPV for women, but decreased the risk for men. The findings also showed that education level and unity were protective against physical IPV for both men and women. Contrary to what was expected, partner data did not play a role in the respondent's experience of IPV. The consistency of these findings with the literature, theory, and study limitations are discussed.

  12. Drugs, sex, money and power: an HPV vaccine case study.

    PubMed

    Haas, Marion; Ashton, Toni; Blum, Kerstin; Christiansen, Terkel; Conis, Elena; Crivelli, Luca; Lim, Meng Kin; Lisac, Melanie; Macadam, Margaret; Schlette, Sophia

    2009-10-01

    In this paper we compare the experiences of seven industrialized countries in considering approval and introduction of the world's first cervical cancer-preventing vaccine. Based on case studies, articles from public agencies, professional journals and newspapers we analyse the public debate about the vaccine, examine positions of stakeholder groups and their influence on the course and outcome of this policy process. The analysis shows that the countries considered here approved the vaccine and established related immunization programs exceptionally quickly even though there still exist many uncertainties as to the vaccine's long-term effectiveness, cost-effectiveness and safety. Some countries even bypassed established decision-making processes. The voice of special interest groups has been prominent in all countries, drawing on societal values and fears of the public. Even though positions differed among countries, all seven decided to publicly fund the vaccine, illustrating a widespread convergence of interests. It is important that decision-makers adhere to transparent and robust guidelines in making funding decisions in the future to avoid capture by vested interests and potentially negative effects on access and equity.

  13. Studies of thermionic materials for space power applications

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The effect of microstructures of tungsten cladding on the transport rates of carbide fuel components was studied at 2073 K. hyperstoichiometric 90UC-10ZrC containing 4 wt% tungsten was clad with six types of tungsten material of 40 mil thickness. Screening tests of 1000 hours were carried out, and then selected samples were subjected to long-term tests up to 10,000 hours. The results indicate that the microstructures strongly affect the transport rates of carbide fuel components. The conditions for preparing (110) oriented cylindrical chloride tungsten emitters of high vacuum work functions were also investigated. Specimen sets were deposited on fluoride tungsten substrates for evaluating the effects of various deposition parameters on the degree and uniformity of the (110) preferred orientation and the vacuum work function. Long-term tests showed that the high vacuum work function of a cylindrical emitter was stable and the chloride tungsten to fluoride tungsten bond remained in excellent shape after 4850 hours at 2073 K.

  14. Longitudinal study of EEG frequency maturation and power changes in children on the Russian North.

    PubMed

    Soroko, S I; Shemyakina, N V; Nagornova, Zh V; Bekshaev, S S

    2014-11-01

    The aim of the study was to reveal longitudinal changes in electroencephalogram spectral power and frequency (percentage frequency composition of EEG and alpha peak frequency) patterns in normal children from northern Russia. Fifteen children (9 girls and 6 boys) participated in the study. The resting state (eyes closed) EEGs were recorded yearly (2005-2013) from age 8 to age 16-17 for each child. EEG frequency patterns were estimated as the percentages of waves with a 1 Hz step revealed by measuring the interval durations between points crossing zero (isoline) by a curve. EEG spectral power changes were analyzed for delta (1.5-4 Hz), theta (4-7.5 Hz), alpha-1 (7.5-9.5 Hz), alpha-2 (9.5-12.5 Hz), beta-1 (12.5-18 Hz) and beta-2 (18-30 Hz) bands. According to the frequency composition of the EEG signals fast synchronous, polymorphous synchronous, polymorphous desynchronous and slow synchronous types of children EEG were revealed. These EEG types were relatively stable during adolescence. In these EEG types, the frequency patterns and spectral power dynamics with age had several common and specific features. Slow wave percentage and spectral power in the delta band remarkably decreased with age in all groups. Starting from the theta band the EEG types were characterized by different EEG spectral power changes with age. In fast synchronous EEG type, the theta and alpha-1 EEG power decreased, and the alpha-2 power increased in the occipital and parietal areas. The polymorphous synchronous type was characterized by increased both the alpha-1 and alpha-2 power with regional peculiarities. In the polymorphous desynchronous type spectral power in all bands decreased with age, and in the slow synchronous type, the alpha-1 power massively increased with age. Obtained results suggest predictive strength of the spatial-frequency patterns in EEG for its following maturation through the years.

  15. Innovative Power Wheelchair Control Interface: A Proof-of-Concept Study.

    PubMed

    Winkler, Sandra L; Romero, Sergio; Prather, Emily; Ramroop, Marisa; Slaibe, Emmy; Christensen, Matthew

    2016-01-01

    Some people without independent mobility are candidates for powered mobility but are unable to use a traditional power wheelchair joystick. This proof-of-concept study tested and further developed an innovative method of driving power wheelchairs for people whose impairments prevent them from operating commercial wheelchair controls. Our concept, Self-referenced Personal Orthotic Omni-purpose Control Interface (SPOOCI), is distinguished by referencing the control sensor not to the wheelchair frame but instead to the adjacent proximal lower-extremity segment via a custom-formed orthosis. Using a descriptive case-series design, we compared the pre-post functional power wheelchair driving skill data of 4 participants, measured by the Power Mobility Program, using descriptive analyses. The intervention consisted of standard-care power wheelchair training during 12 outpatient occupational or physical therapy sessions. All 4 participants who completed the 12-wk intervention improved their functional power wheelchair driving skills using SPOOCI, but only 3 were deemed safe to continue with power wheelchair driving.

  16. Innovative Power Wheelchair Control Interface: A Proof-of-Concept Study

    PubMed Central

    Romero, Sergio; Prather, Emily; Ramroop, Marisa; Slaibe, Emmy; Christensen, Matthew

    2016-01-01

    Some people without independent mobility are candidates for powered mobility but are unable to use a traditional power wheelchair joystick. This proof-of-concept study tested and further developed an innovative method of driving power wheelchairs for people whose impairments prevent them from operating commercial wheelchair controls. Our concept, Self-referenced Personal Orthotic Omni-purpose Control Interface (SPOOCI), is distinguished by referencing the control sensor not to the wheelchair frame but instead to the adjacent proximal lower-extremity segment via a custom-formed orthosis. Using a descriptive case-series design, we compared the pre–post functional power wheelchair driving skill data of 4 participants, measured by the Power Mobility Program, using descriptive analyses. The intervention consisted of standard-care power wheelchair training during 12 outpatient occupational or physical therapy sessions. All 4 participants who completed the 12-wk intervention improved their functional power wheelchair driving skills using SPOOCI, but only 3 were deemed safe to continue with power wheelchair driving. PMID:26943118

  17. Multivariate test power approximations for balanced linear mixed models in studies with missing data.

    PubMed

    Ringham, Brandy M; Kreidler, Sarah M; Muller, Keith E; Glueck, Deborah H

    2016-07-30

    Multilevel and longitudinal studies are frequently subject to missing data. For example, biomarker studies for oral cancer may involve multiple assays for each participant. Assays may fail, resulting in missing data values that can be assumed to be missing completely at random. Catellier and Muller proposed a data analytic technique to account for data missing at random in multilevel and longitudinal studies. They suggested modifying the degrees of freedom for both the Hotelling-Lawley trace F statistic and its null case reference distribution. We propose parallel adjustments to approximate power for this multivariate test in studies with missing data. The power approximations use a modified non-central F statistic, which is a function of (i) the expected number of complete cases, (ii) the expected number of non-missing pairs of responses, or (iii) the trimmed sample size, which is the planned sample size reduced by the anticipated proportion of missing data. The accuracy of the method is assessed by comparing the theoretical results to the Monte Carlo simulated power for the Catellier and Muller multivariate test. Over all experimental conditions, the closest approximation to the empirical power of the Catellier and Muller multivariate test is obtained by adjusting power calculations with the expected number of complete cases. The utility of the method is demonstrated with a multivariate power analysis for a hypothetical oral cancer biomarkers study. We describe how to implement the method using standard, commercially available software products and give example code. Copyright © 2015 John Wiley & Sons, Ltd.

  18. Global Uranium And Thorium Resources: Are They Adequate To Satisfy Demand Over The Next Half Century?

    NASA Astrophysics Data System (ADS)

    Lambert, I. B.

    2012-04-01

    This presentation will consider the adequacy of global uranium and thorium resources to meet realistic nuclear power demand scenarios over the next half century. It is presented on behalf of, and based on evaluations by, the Uranium Group - a joint initiative of the OECD Nuclear Energy Agency and the International Atomic Energy Agency, of which the author is a Vice Chair. The Uranium Group produces a biennial report on Uranium Resources, Production and Demand based on information from some 40 countries involved in the nuclear fuel cycle, which also briefly reviews thorium resources. Uranium: In 2008, world production of uranium amounted to almost 44,000 tonnes (tU). This supplied approximately three-quarters of world reactor requirements (approx. 59,000 tU), the remainder being met by previously mined uranium (so-called secondary sources). Information on availability of secondary sources - which include uranium from excess inventories, dismantling nuclear warheads, tails and spent fuel reprocessing - is incomplete, but such sources are expected to decrease in market importance after 2013. In 2008, the total world Reasonably Assured plus Inferred Resources of uranium (recoverable at less than 130/kgU) amounted to 5.4 million tonnes. In addition, it is clear that there are vast amounts of uranium recoverable at higher costs in known deposits, plus many as yet undiscovered deposits. The Uranium Group has concluded that the uranium resource base is more than adequate to meet projected high-case requirements for nuclear power for at least half a century. This conclusion does not assume increasing replacement of uranium by fuels from reprocessing current reactor wastes, or by thorium, nor greater reactor efficiencies, which are likely to ameliorate future uranium demand. However, progressively increasing quantities of uranium will need to be mined, against a backdrop of the relatively small number of producing facilities around the world, geopolitical uncertainties and

  19. [Quality of Mesorectal Excision ("Plane of Surgery") - Which Quality Targets are Adequate?].

    PubMed

    Hermanek, P; Merkel, S; Ptok, H; Hohenberger, W

    2015-12-01

    Today, the examination of rectal cancer specimens includes the obligate macroscopic assessment of the quality of mesorectal excision by the pathologist reporting the plane of surgery. The frequency of operations in the muscularis propria plane of surgery (earlier described as incomplete mesorectal excision) is essential. The quality of mesorectal excision is important for the prognosis, especially as local recurrences are observed more frequently after operations in the muscularis propria plane of surgery. For the definition of quality targets, data of 13 studies published between 2006 and 2012, each with more than 100 patients and adequate specialisation and experience of the surgeons (5413 patients), data of the prospective multicentric observation study "Quality Assurance - Rectal Cancer" (at the Institute for Quality Assurance in Operative Medicine at the Otto-von-Guericke University at Magdeburg) from 2005 to 2010 (8044 patients) and data of the Department of Surgery, University Hospital Erlangen, from 1998 to 2011 (991 patients) were analysed. The total incidence of operations in the muscularis propria plane of surgery was 5.0 % (721/14 448). Even with adequate specialisation and experience of the surgeon, the frequency of operations in the muscularis propria plane of surgery is higher in abdominoperineal excisions than in sphincter-preserving surgery (8.4 vs. 2.8 %, p < 0.001). Thus, the quality target for the frequency of operations in the muscularis propria plane should be defined as < 5 % for sphincter-preserving procedures and as < 10 % for abdominoperineal excisions.

  20. When one is not enough: prevalence and characteristics of homes not adequately protected by smoke alarms

    PubMed Central

    Peek-Asa, C; Allareddy, V; Yang, J; Taylor, C; Lundell, J; Zwerling, C

    2005-01-01

    Objective: The National Fire Protection Association (NFPA) has specific recommendations about the number, location, and type of smoke alarms that are needed to provide maximum protection for a household. No previous studies have examined whether or not homes are completely protected according to these guidelines. The authors describe the prevalence and home characteristics associated with compliance to recommendations for smoke alarm installation by the NFPA. Design, setting, and subjects: Data are from the baseline on-site survey of a randomized trial to measure smoke alarm effectiveness. The trial was housed in a longitudinal cohort study in a rural Iowa county. Of 1005 homes invited, 691 (68.8%) participated. Main outcome measures: Information about smoke alarm type, placement, and function, as well as home and occupant characteristics, was collected through an on-site household survey. Results: Although 86.0% of homes had at least one smoke alarm, only 22.3% of homes (approximately one in five) were adequately protected according to NFPA guidelines. Fourteen percent of homes had no functioning smoke alarms. More than half of the homes with smoke alarms did not have enough of them or had installed them incorrectly, and 42.4% of homes with alarms had at least one alarm that did not operate. Homes with at least one high school graduate were nearly four times more likely to be fully protected. Homes that had multiple levels, a basement, or were cluttered or poorly cleaned were significantly less likely to be fully protected. Conclusion: These findings indicate that consumers may not be knowledgeable about the number of alarms they need or how to properly install them. Occupants are also not adequately maintaining the alarms that are installed. PMID:16326772

  1. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND PLANT... and Adequate Veterinary Care § 2.40 Attending veterinarian and adequate veterinary care (dealers and... veterinary care to its animals in compliance with this section. (1) Each dealer and exhibitor shall employ...

  2. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... adequate veterinary care. (a) Each research facility shall have an attending veterinarian who shall provide adequate veterinary care to its animals in compliance with this section: (1) Each research facility...

  3. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  4. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  5. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  6. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  7. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  8. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 3 2013-10-01 2013-10-01 false Adequate financial records, statistical data, and....568 Adequate financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination...

  9. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 3 2014-10-01 2014-10-01 false Adequate financial records, statistical data, and....568 Adequate financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination...

  10. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 3 2012-10-01 2012-10-01 false Adequate financial records, statistical data, and....568 Adequate financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination...

  11. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Assurances of adequate capacity and services. 438... Improvement Access Standards § 438.207 Assurances of adequate capacity and services. (a) Basic rule. The State... provides supporting documentation that demonstrates that it has the capacity to serve the...

  12. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Assurances of adequate capacity and services. 438... Improvement Access Standards § 438.207 Assurances of adequate capacity and services. (a) Basic rule. The State... provides supporting documentation that demonstrates that it has the capacity to serve the...

  13. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Assurances of adequate capacity and services. 438... Improvement Access Standards § 438.207 Assurances of adequate capacity and services. (a) Basic rule. The State... provides supporting documentation that demonstrates that it has the capacity to serve the...

  14. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Assurances of adequate capacity and services. 438... Improvement Access Standards § 438.207 Assurances of adequate capacity and services. (a) Basic rule. The State... provides supporting documentation that demonstrates that it has the capacity to serve the...

  15. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Research Facilities § 2.33 Attending veterinarian and adequate veterinary care. (a) Each research facility shall have an attending veterinarian who shall provide adequate veterinary care to its animals in compliance with this section: (1) Each research facility...

  16. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Research Facilities § 2.33 Attending veterinarian and adequate veterinary care. (a) Each research facility shall have an attending veterinarian who shall provide adequate veterinary care to its animals in compliance with this section: (1) Each research facility...

  17. Feasibility Study of a Nuclear-Stirling Power Plant for the Jupiter Icy Moons Orbiter

    NASA Astrophysics Data System (ADS)

    Schmitz, Paul C.; Schreiber, Jeffrey G.; Penswick, L. Barry

    2005-02-01

    NASA is undertaking the design of a new spacecraft to explore the planet Jupiter and its three moons Calisto, Ganymede and Europa. This proposed mission, known as Jupiter Icy Moons Orbiter (JIMO) would use a nuclear reactor and an associated electrical generation system (Reactor Power Plant - RPP) to provide power to the spacecraft. The JIMO spacecraft is envisioned to use this power for science and communications as well as Electric Propulsion (EP). Among other potential power-generating concepts, previous studies have considered Thermoelectric and Brayton power conversion systems, coupled to a liquid metal reactor for the JIMO mission. This paper will explore trades in system mass and radiator area for a nuclear reactor power conversion system, however this study will focus on Stirling power conversion. Stirling convertors have a long heritage operating in both power generation and the cooler industry, and are currently in use in a wide variety of applications. The Stirling convertor modeled in this study is based upon the Component Test Power Convertor design that was designed and operated successfully under the Civil Space Technology Initiative for use with the SP-100 nuclear reactor in the 1980's and early 1990's. The baseline RPP considered in this study consists of four dual-opposed Stirling convertors connected to the reactor by a liquid lithium loop. The study design is such that two of the four convertors would operate at any time to generate the 100 kWe while the others are held in reserve. For this study the Stirling convertors hot-side temperature is 1050 K, would operate at a temperature ratio of 2.4 for a minimum mass system and would have a system efficiency of 29%. The Stirling convertor would generate high voltage (400 volt), 100 Hz single phase AC that is supplied to the Power Management and Distribution system. The waste heat is removed from the Stirling convertors by a flowing liquid sodium-potassium eutectic and then rejected by a shared

  18. Preliminary study, analysis and design for a power switch for digital engine actuators

    NASA Technical Reports Server (NTRS)

    Beattie, E. C.; Zickwolf, H. C., Jr.

    1979-01-01

    Innovative control configurations using high temperature switches to operate actuator driving solenoids were studied. The impact on engine control system life cycle costs and reliability of electronic control and (ECU) heat dissipation due to power conditioning and interface drivers were addressed. Various power supply and actuation schemes were investigated, including optical signal transmission and electronics on the actuator, engine driven alternator, and inside the ECU. The use of a switching shunt power conditioner results in the most significant decrease in heat dissipation within the ECU. No overall control system reliability improvement is projected by the use of remote high temperature switches for solenoid drivers.

  19. 2240-MW(th) high-temperature reactor core power density study

    SciTech Connect

    Vondy, D.R.

    1984-09-01

    This study was done to estimate the effects of reducing the design power density of a 2240-MW(t) high-temperature gas-cooled reactor. Core history and thermal hydraulics calculations were performed for average power densities of 5.8 and 7.2 W/cm/sup 3/ and the use of highly enriched fuel was considered. The fuel temperature conditions for the higher power density were found to be only moderately elevated at normal operating conditions. Economic considerations associated with changes in core performance, core size, and coolant pumping requirements were assessed.

  20. Power, technology and social studies of health care: an infrastructural inversion.

    PubMed

    Jensen, Casper Bruun

    2008-12-01

    Power, dominance, and hierarchy are prevalent analytical terms in social studies of health care. Power is often seen as residing in medical structures, institutions, discourses, or ideologies. While studies of medical power often draw on Michel Foucault, this understanding is quite different from his proposal to study in detail the "strategies, the networks, the mechanisms, all those techniques by which a decision is accepted" [Foucault, M. (1988). In Politics, philosophy, culture: Interviews and other writings 1977-84 (pp. 96-109). New York: Routledge]. This suggestion turns power into a topic worth investigating in its own right rather than a basic analytical resource. It also suggests that technologies form an integral part of the networks and mechanisms, which produce and redistribute power in medical practice. The paper first engages critically with a number of recent discussions of technology and power in health care analysis. It then formulates an alternative conception of this relationship by drawing on Foucault and historian of science and technology Geoffrey C. Bowker's notions of infrastructural inversion and information mythology. Illustration is provided through a case study of a wireless nursing call system in a Canadian hospital.

  1. Satellite Power Systems (SPS) laser studies. Volume 1: Laser environmental impact study

    NASA Technical Reports Server (NTRS)

    Beverly, R. E., III

    1980-01-01

    The environmental impact of space to Earth power transmission using space borne laser subsystems is emphasized. A laser system is defined, estimates of relevant efficiencies for laser power generation and atmospheric transmission are developed, and a comparison is made to a microwave system. Ancillary issues, such as laser beam spreading, safety and security, mass and volume estimates and technology growth are considered.

  2. Feasibility study on optimization of a typical solar chimney power plant

    NASA Astrophysics Data System (ADS)

    Najmi, Mohsen; Nazari, Ali; Mansouri, Hossein; Zahedi, Ghazzanfar

    2012-03-01

    The solar chimney which has been built in Kerman (Kerman city-Iran) is a small scale electrical power plant. The chimney of this unit has 60 m height and 3 m diameter. The collector of this unit is 40 m × 40 m square. To reach nominal power of this unit of power plant, parameters which are effective in optimization are studied. In this regard, we deliberate and propose suggestions to maximize usage of solar energy and kinetic energy. The calculation of maximum power is one of the objectives of this study, so the paper present economic analysis for Kerman solar chimney. A home code has been written for this modeling, in MATLAB.

  3. McHuchuma/Katewaka coal fired power plant feasibility study. Final report. Export trade information

    SciTech Connect

    1996-11-22

    This study, conducted by Black and Veatch International, was funded by the U.S. Trade and Development Agency. The report assesses the feasibility for the development of a new coal fueled power plant in Tanzania at the Mchuchuma/Katewaka coal concession area. Volume 3, the Main Report, is divided into the following sections: (1.0) Introduction; (2.0) Power System Development Studies; (3.0) Conceptual Design Summary of the Mchuchuma Coal Fired Power Plant; (4.0) Fuel Supply Evaluation; (5.0) Transmission System Evaluation; (6.0) Power Plant Site and Infrastructure Evaluation; (7.0) Environmental Impact Assessment; (8.0) Institutional Aspects; (9.0) Financial Evaluation and Benefit Analysis; (10.0) Sources of Finance; Appendix (A) Preliminary Design of Mchuchuma Coal Plant.

  4. A Comparative Study of Power Supply Architectures In Wireless Electric Vehicle Charging Systems

    NASA Astrophysics Data System (ADS)

    Esteban, Bryan

    Wireless inductive power transfer is a transformational and disruptive technology that enables the reliable and efficient transfer of electrical power over large air gaps for a host of unique applications. One such application that is now gaining much momentum worldwide is the wireless charging of electric vehicles (EVs). This thesis examines two of the primary power supply topologies being predominantly used for EV charging, namely the SLC and the LCL resonant full bridge inverter topologies. The study of both of these topologies is presented in the context of designing a 3 kW, primary side controlled, wireless EV charger with nominal operating parameters of 30 kHz centre frequency and range of coupling in the neighborhood of .18-.26. A comparison of both topologies is made in terms of their complexity, cost, efficiency, and power quality. The aim of the study is to determine which topology is better for wireless EV charging.

  5. Numerical study on a 0.4 THz second harmonic gyrotron with high power

    SciTech Connect

    Chaojun, Lei; Sheng, Yu; Hongfu, Li; Yinghui, Liu; Xinjian, Niu; Qixiang, Zhao

    2013-07-15

    Terahertz and sub-terahertz science and technology are promising topics today. However, it is difficult to obtain high power source of terahertz wave. In this paper, the mode competition and beam-wave interaction in a gradually tapered cavity are studied to achieve high efficiency of a 0.4THz second harmonic gyrotron in practice. In order to attain high power and stable radiation, the TE{sub 32,5} mode is selected as the operating mode of the desired gyrotron to realize single mode oscillation. The issues of studying on the high-order mode gyrotrons are solved effectively by transforming the generalized telegraphist's equations. The efficiency and output power of the gyrotron under different conditions have been calculated by the code, which is based on the transformed equations. Consequently, the results show that single mode second harmonic radiation with power of over 150 kW at frequency of 0.4 THz could be achieved.

  6. Cost Study for Manufacturing of Solid Oxide Fuel Cell Power Systems

    SciTech Connect

    Weimar, Mark R.; Chick, Lawrence A.; Gotthold, David W.; Whyatt, Greg A.

    2013-09-30

    Solid oxide fuel cell (SOFC) power systems can be designed to produce electricity from fossil fuels at extremely high net efficiencies, approaching 70%. However, in order to penetrate commercial markets to an extent that significantly impacts world fuel consumption, their cost will need to be competitive with alternative generating systems, such as gas turbines. This report discusses a cost model developed at PNNL to estimate the manufacturing cost of SOFC power systems sized for ground-based distributed generation. The power system design was developed at PNNL in a study on the feasibility of using SOFC power systems on more electric aircraft to replace the main engine-mounted electrical generators [Whyatt and Chick, 2012]. We chose to study that design because the projected efficiency was high (70%) and the generating capacity was suitable for ground-based distributed generation (270 kW).

  7. 45 CFR 1159.15 - Who has the responsibility for maintaining adequate technical, physical, and security safeguards...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... adequate technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of... adequate technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of... of maintaining adequate technical, physical, and security safeguards to prevent...

  8. 45 CFR 1159.15 - Who has the responsibility for maintaining adequate technical, physical, and security safeguards...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... adequate technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of... adequate technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of... of maintaining adequate technical, physical, and security safeguards to prevent...

  9. Power analysis for case–control association studies of samples with known family histories

    PubMed Central

    Li, Biao; Han, Younghun; Amos, Christopher I.

    2014-01-01

    Genome-wide case–control studies have been widely used to identify genetic variants that predispose to human diseases. Such studies are powerful in detecting common genetic variants with moderate effects, but quickly lose power as allele frequency and genotype relative risk decrease. Because patients with one or more affected relatives are more likely to inherit disease-predisposing alleles of a genetic disease than patients without family histories of the disease, sampling patients with affected relatives almost always increases the frequency of disease predisposing alleles in cases and improves the power of case–control association studies. This paper evaluates the power of case–control studies that select cases and/or controls according to their family histories of disease. Our results showed that this study design can dramatically increase the power of a case–control association study for a wide range of disease types. Because each additional affected relative of a patient reduces the required sample size roughly by a pair of case and control, inclusion of cases with affected relatives can dramatically decrease the required sample size and thus the cost of such studies. PMID:20383776

  10. Study of effects of space power satellites on life support functions of the earth's magnetosphere

    NASA Technical Reports Server (NTRS)

    Douglas, M.; Laquey, R.; Deforest, S. E.; Lindsey, C.; Warshaw, H.

    1977-01-01

    The effects of the Satellite Solar Power System (SSPS) on the life support functions of the earth's magnetosphere were investigated. Topics considered include: (1) thruster effluent effects on the magnetosphere; (2) biological consequences of SSPS reflected light; (3) impact on earth bound astronomy; (4) catastrophic failure and debris; (5) satellite induced processes; and (6) microwave power transmission. Several impacts are identified and recommendations for further studies are provided.

  11. Analytical study of solitons in the fiber waveguide with power law nonlinearity

    NASA Astrophysics Data System (ADS)

    Mirzazadeh, Mohammad; Ekici, Mehmet; Zhou, Qin; Sonmezoglu, Abdullah

    2017-01-01

    This work deals with the existence of exact soliton solutions in fiber waveguide with power law nonlinearity. The propagation equation that is the resonant dispersive nonlinear Schrödinger's equation with power law nonlinearity is studied by three analytical methods. The integration tools are the extended trial equation method, exp(-Φ(ξ)) -expansion method and extended G‧ / G - expansion method. The presented results show that analytical optical solitons can exist in this setting.

  12. Maturational Patterns of Sigma Frequency Power Across Childhood and Adolescence: A Longitudinal Study

    PubMed Central

    Campbell, Ian G.; Feinberg, Irwin

    2016-01-01

    Study Objectives: To further evaluate adolescent brain maturation by determining the longitudinal trajectories of nonrapid eye movement (NREM) sigma (11–15 Hz) power across childhood-adolescence. Methods: The maturational trend for sigma (11–15 Hz) power was evaluated in an accelerated longitudinal study of three overlapping age cohorts (n = 92) covering ages 6 to 18 y. Semiannually, sleep electroencephalography (EEG) was recorded from participants sleeping at home in their normal sleep environment while keeping their current school night schedules. Results: Sigma frequencies became faster with age. The frequency of the 11–15 Hz spectral peak increased linearly. Sigma frequency power (SFP) declined with age, but its trajectory was complex (cubic). Power in a group of low sigma subfrequencies declined with age. Power in a group of high sigma frequencies increased with age. Power in subfrequencies within 11–15 Hz also showed different trends across the night, with lower frequencies increasing across NREM periods and higher frequencies decreasing across NREM periods. The upper and lower boundaries for the sigma frequencies that changed across NREMPs shifted upward with age. Conclusions: We hypothesize that these maturational brain changes result from synaptic elimination which decreases sleep depth and streamlines circuits. SFP displays a maturational trajectory different from both delta and theta power. Theories on the function of sigma must be reconciled with its maturational trajectory. These findings further demonstrate the value of sleep EEG for studying noninvasively the complex developmental brain changes of adolescence. Citation: Campbell IG, Feinberg I. Maturational patterns of sigma frequency power across childhood and adolescence: a longitudinal study. SLEEP 2016;39(1):193–201. PMID:26285004

  13. Final report for the field-reversed configuration power plant critical-issue scoping study

    SciTech Connect

    Santarius, John F.; Mogahed, Elsayed A.; Emmert, Gilbert A.; Khater, Hesham Y.; Nguyen, Canh N.; Ryzhkov, Sergei V.; Stubna, Michael D.; Steinhauer, Loren C.; Miley, George H.

    2001-03-01

    This report describes research in which a team from the Universities of Wisconsin, Washington, and Illinois performed a scoping study of critical issues for field-reversed configuration (FRC) power plants. The key tasks for this research were (1) systems analysis of deuterium-tritium (D-T) FRC fusion power plants, and (2) conceptual design of the blanket and shield module for an FRC fusion core.

  14. Studies of Plasma Instability Processes Excited by Ground Based High Power HF ("Heating") Facilities

    DTIC Science & Technology

    2001-04-01

    by ground based high power HF (’ heating ’) facilities 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Dr. Alexander...Prescribed by ANSI Std. Z39-18 Grant SPC 00-4010 Final Report STUDIES OF PLASMA INSTABILITY PROCESSES EXCITED BY GROUND BASED HIGH POWER HF (" HEATING ...growing field of ionospheric HF heating . The main new results can be summarized as following: 1. Two sets of observations of suprathermal electrons

  15. A Summary of NASA Architecture Studies Utilizing Fission Surface Power Technology

    NASA Technical Reports Server (NTRS)

    Mason, Lee S.; Poston, David I.

    2011-01-01

    Beginning with the Exploration Systems Architecture Study in 2005, NASA has conducted various mission architecture studies to evaluate implementation options for the U.S. Space Policy. Several of the studies examined the use of Fission Surface Power (FSP) systems for human missions to the lunar and Martian surface. This paper summarizes the FSP concepts developed under four different NASA-sponsored architecture studies: Lunar Architecture Team, Mars Architecture Team, Lunar Surface Systems/Constellation Architecture Team, and International Architecture Working Group-Power Function Team.

  16. A Nomogram to Predict Adequate Lymph Node Recovery before Resection of Colorectal Cancer

    PubMed Central

    Zhang, Zhen-yu; Li, Cong; Gao, Wei; Yin, Xiao-wei; Luo, Qi-feng; Liu, Nan; Basnet, Shiva; Dai, Zhen-ling; Ge, Hai-yan

    2016-01-01

    Increased lymph node count (LNC) has been associated with prolonged survival in colorectal cancer (CRC), but the underlying mechanisms are still poorly understood. The study aims to identify new predictors and develop a preoperative nomogram for predicting the probability of adequate LNC (≥ 12). 501 eligible patients were retrospectively selected to identify clinical-pathological factors associated with LNC ≥ 12 through univariate and multivariate logistic regression analyses. The nomogram was built according to multivariate analyses of preoperative factors. Model performance was assessed with concordance index (c-index) and area under the receiver operating characteristic curve (AUC), followed by internal validation and calibration using 1000-resample bootstrapping. Clinical validity of the nomogram and LNC impact on stage migration were also evaluated. Multivariate analyses showed patient age, CA19-9, circulating lymphocytes, neutrophils, platelets, tumor diameter, histology and deposit significantly correlated with LNC (P < 0.05). The effects were marginal for CEA, anemia and CRC location (0.05 < P < 0.1). The multivariate analyses of preoperative factors suggested decreased age, CEA, CA19-9, neutrophils, proximal location, and increased platelets and diameter were significantly associated with increased probability of LNC ≥ 12 (P < 0.05). The nomogram achieved c-indexes of 0.75 and 0.73 before and after correction for overfitting. The AUC was 0.75 (95% CI, 0.70–0.79) and the clinically valid threshold probabilities were between 10% and 60% for the nomogram to predict LNC < 12. Additionally, increased probability of adequate LNC before surgery was associated with increased LNC and negative lymph nodes rather than increased positive lymph nodes, lymph node ratio, pN stages or AJCC stages. Collectively, the results indicate the LNC is multifactorial and irrelevant to stage migration. The significant correlations with preoperative circulating markers may

  17. Use of Linear Programming to Develop Cost-Minimized Nutritionally Adequate Health Promoting Food Baskets

    PubMed Central

    Tetens, Inge; Dejgård Jensen, Jørgen; Smed, Sinne; Gabrijelčič Blenkuš, Mojca; Rayner, Mike; Darmon, Nicole; Robertson, Aileen

    2016-01-01

    Background Food-Based Dietary Guidelines (FBDGs) are developed to promote healthier eating patterns, but increasing food prices may make healthy eating less affordable. The aim of this study was to design a range of cost-minimized nutritionally adequate health-promoting food baskets (FBs) that help prevent both micronutrient inadequacy and diet-related non-communicable diseases at lowest cost. Methods Average prices for 312 foods were collected within the Greater Copenhagen area. The cost and nutrient content of five different cost-minimized FBs for a family of four were calculated per day using linear programming. The FBs were defined using five different constraints: cultural acceptability (CA), or dietary guidelines (DG), or nutrient recommendations (N), or cultural acceptability and nutrient recommendations (CAN), or dietary guidelines and nutrient recommendations (DGN). The variety and number of foods in each of the resulting five baskets was increased through limiting the relative share of individual foods. Results The one-day version of N contained only 12 foods at the minimum cost of DKK 27 (€ 3.6). The CA, DG, and DGN were about twice of this and the CAN cost ~DKK 81 (€ 10.8). The baskets with the greater variety of foods contained from 70 (CAN) to 134 (DGN) foods and cost between DKK 60 (€ 8.1, N) and DKK 125 (€ 16.8, DGN). Ensuring that the food baskets cover both dietary guidelines and nutrient recommendations doubled the cost while cultural acceptability (CAN) tripled it. Conclusion Use of linear programming facilitates the generation of low-cost food baskets that are nutritionally adequate, health promoting, and culturally acceptable. PMID:27760131

  18. A Study on Modeling of Transmission Line in Digital Type Real-Time Power System Simulator

    NASA Astrophysics Data System (ADS)

    Yasuda, Yuji; Yokoyama, Akihiko; Tada, Yasuyuki

    In modern power systems, it is important to analyze various kindes of dynamic phenomena which appear in the system. When the effectiveness of new power electronics based apparatus, protective relay systems and etc. is tested, a real-time power system simulator is becoming a very effective tool. In general, however, it is very expensive and it is very difficult for beginners to understand how to use it. Therefore, studies on low-cost and easy-use real-time power system simulators have so far been done. We have developed models of power system components for the real-time power system simulator using DSP (Digital Signal Processor) combined with commercial CAD (Computer Aided Design) soft "MATLAB/SIMULINK". The use of commercial softwares can drastically decrease the development cost of the simulator. In this paper, a simplified reduction model of unbalanced three-phase transmission network with mutual impedance is proposed for analysis of various kinds of stability phenomena by use of the digital simulator. The proposed network model is constructed automatically and efficiently even for connection of both current source type models and voltage source type models of power apparatus such as generators, FACTS devices and loads.

  19. Gigawatt, Closed Cycle, Vapor Core-Mhd Space Power System Conceptual Design Study

    NASA Astrophysics Data System (ADS)

    Wetch, Joseph R.; Rhee, Hyop S.; Koester, J. Kent; Goodman, Julius; Maya, Issac

    1988-04-01

    A conceptual design study for a closed cycle gigawatt electric space power system has been conducted. The closed cycle static operation reduces power system interaction effects upon the space craft. This system utilizes a very high temperature (5500 K) plasma core reactor and a magnetohydrodynamic (MHD) power conversion subsystem to provide a power density of about 8 kWe/kg (0.13 kg/kWe) for several kilo-seconds. Uranium vapor is the fuel. Candidate working fluids are metal vapors such as lithium or calcium. The system is based on a Rankine cycle to minimize the electromagnetic pumping power requirement. The fission fragment induced nonequilibrium ionization in the plasma in the MHD power duct provides the plasma electric conductivity for gigawatt power generation. Waste heat is rejected utilizing lithium heat pipes at temperatures just below 2000 K, thus minimizing the radiator area requirement. Key technology issues are identified, including the containment of the 5500 K 'sun-liken plasma at 4 to 0 MPa In a reflector moderated, gas/vapor filled cavity core reactor. A promising scheme to protect the refractory metal reactor inner wall is presented, together with a heating load analysis in the wall. This scheme utilizes an ablating film of liquid lithium/calcium that evaporates into the cavity core to become the working fluid of the cycle.

  20. Study on a hypothetical replacement of nuclear electricity by wind power in Sweden

    NASA Astrophysics Data System (ADS)

    Wagner, F.; Rachlew, E.

    2016-05-01

    The Swedish electricity supply system benefits strongly from the natural conditions which allow a high share of hydroelectricity. A complete supply is, however, not possible. Up to now, nuclear power is the other workhorse to serve the country with electricity. Thus, electricity production of Sweden is basically CO2 -free and Sweden has reached an environmental status which others in Europe plan to reach in 2050. Furthermore, there is an efficient exchange within the Nordic countries, Nordpol, which can ease possible capacity problems during dry cold years. In this study we investigate to what extent and with what consequences the base load supply of nuclear power can be replaced by intermittent wind power. Such a scenario leads unavoidably to high wind power installations. It is shown that hydroelectricity cannot completely smooth out the fluctuations of wind power and an additional back-up system using fossil fuel is necessary. From the operational dynamics, this system has to be based on gas. The back-up system cannot be replaced by a storage using surplus electricity from wind power. The surplus is too little. To overcome this, further strong extension of wind power is necessary which leads, however, to a reduction of the use of hydroelectricity if the annual consumption is kept constant. In this case one fossil-free energy form is replaced by another, however, more complex one. A mix of wind power at 22.3GW plus a gas based back-up system with 8.6GW producing together 64.8TWh would replace the present infrastructure with 9GW nuclear power producing 63.8TWh electricity. The specific CO2 -emission increases to the double in this case. Pumped storage for the exclusive supply of Sweden does not seem to be a meaningful investment.-1

  1. Economic Development Impacts of Wind Power--Case Studies Fact Sheet

    SciTech Connect

    NWCC Economic Development Work Group

    2003-12-17

    OAK-B135 Interest in wind power development is growing as a means of expanding local economies. Such development holds promise as a provider of short-term employment during facility construction and long-term employment from ongoing facility operation and maintenance (O&M). It may also add to the supply of electric power in the area and support some expansion of the local economy through ripple effects resulting from initial increases in jobs and income. These ripple effects stem from subsequent expenditures for goods and services made possible by first-round income from the development, and are expressed in terms of a multiplier. If the local economy offers a wide range of goods and services the resulting multiplier can be substantial--as much as three or four. If not, then much of the initial income will leave the local economy to buy goods and services from elsewhere. Loss of initial income to other locales is referred to as a leakage. While there is a growing body of information about the local impacts of wind power, the economic impacts from existing wind power developments have not been thoroughly and consistently analyzed. Northwest Economic Associates, under contract to the National Wind Coordinating Committee (NWCC), conducted a study and produced a report entitled ''Assessing the Economic Development Impacts of Wind Power.'' The primary objective of the study was to provide examples of appropriate analyses and documentation of economic impacts from wind power development, using case studies of three existing projects in the United States. The findings from the case studies are summarized here; more detail is available in the report, available at NWCC's website http://www.nationalwind.org/. It should be noted that specific results presented apply only to the respective locales studied and are not meant to be representative of wind power in general. However, qualitative findings, discussed below, are likely to be replicated in most areas where wind

  2. Empirical power and sample size calculations for cluster-randomized and cluster-randomized crossover studies.

    PubMed

    Reich, Nicholas G; Myers, Jessica A; Obeng, Daniel; Milstone, Aaron M; Perl, Trish M

    2012-01-01

    In recent years, the number of studies using a cluster-randomized design has grown dramatically. In addition, the cluster-randomized crossover design has been touted as a methodological advance that can increase efficiency of cluster-randomized studies in certain situations. While the cluster-randomized crossover trial has become a popular tool, standards of design, analysis, reporting and implementation have not been established for this emergent design. We address one particular aspect of cluster-randomized and cluster-randomized crossover trial design: estimating statistical power. We present a general framework for estimating power via simulation in cluster-randomized studies with or without one or more crossover periods. We have implemented this framework in the clusterPower software package for R, freely available online from the Comprehensive R Archive Network. Our simulation framework is easy to implement and users may customize the methods used for data analysis. We give four examples of using the software in practice. The clusterPower package could play an important role in the design of future cluster-randomized and cluster-randomized crossover studies. This work is the first to establish a universal method for calculating power for both cluster-randomized and cluster-randomized clinical trials. More research is needed to develop standardized and recommended methodology for cluster-randomized crossover studies.

  3. Satellite Power Systems (SPS) concept definition study, exhibit C. Volume 2, part 1: System engineering

    NASA Technical Reports Server (NTRS)

    Hanley, G. M.

    1979-01-01

    Volume 2, Part 1, of a seven volume report is presented. Part 1 encompasses Satellite Power Systems (SPS) systems engineering aspects and is divided into three sections. The first section presents descriptions of the various candidate concepts considered and conclusions and recommendations for a preferred concept. The second section presents a summary of results of the various trade studies and analysis conducted during the course of the study. The third section describes the Photovoltaic Satellite Based Satellite Power System (SPS) Point Design as it was defined through studies performed during the period January 1977 through March 1979.

  4. Benchmark Study and Characterization of European Rad-Hard Power MOSFEts for Space Applications

    NASA Astrophysics Data System (ADS)

    Becherer, J.; Dittrich, R.; Muschitiello, M.; Constantino, A.

    2014-08-01

    Power Field Effect Transistors are an integral part of the electronic equipment of every space vehicle. In order to survive the harsh conditions of space, the transistors have to fulfill rigorous conditions. A number one in the list of space qualification criteria is the guarantee of radiation hardness. Today several radiation hard Power MOSFETs are available from a variety of companies all over the world. A benchmark study of the available Power MOSFETs for space applications has been compiled in this paper. The newly developed European Superjunction Technologies Power MOSFETs from Infineon show the best performance. Therefore, a total ionizing dose characterization of the 250 V and 150 V European MOSFETs have been performed.

  5. Field-Reversed Configuration Power Plant Critical-Issue Scoping Study

    SciTech Connect

    Santarius, J. F.; Mogahed, E. A.; Emmert, G. A.; Khater, H. Y.; Nguyen, C. N.; Ryzhkov, S. V.; Stubna, M. D.

    2000-03-31

    A team from the Universities of Wisconsin, Washington, and Illinois performed an engineering scoping study of critical issues for field-reversed configuration (FRC) power plants. The key tasks for this research were (1) systems analysis for deuterium-tritium (D-T) FRC fusion power plants, and (2) conceptual design of the blanket and shield module for an FRC fusion core. For the engineering conceptual design of the fusion core, the project team focused on intermediate-term technology. For example, one decision was to use steele structure. The FRC systems analysis led to a fusion power plant with attractive features including modest size, cylindrical symmetry, good thermal efficiency (52%), relatively easy maintenance, and a high ratio of electric power to fusion core mass, indicating that it would have favorable economics.

  6. Energy Optimization Modeling of Geothermal Power Plant (Case Study: Darajat Geothermal Field Unit III)

    NASA Astrophysics Data System (ADS)

    Sinaga, R. H. M.; Darmanto, P. S.

    2016-09-01

    Darajat unit III geothermal power plant is developed by PT. Chevron Geothermal Indonesia (CGI). The plant capacity is 121 MW and load 110%. The greatest utilization power is consumed by Hot Well Pump (HWP) and Cooling Tower Fan (CTF). Reducing the utility power can be attempted by utilizing the wet bulb temperature fluctuation. In this study, a modelling process is developed by using Engineering Equation Solver (EES) software version 9.430.The possibility of energy saving is indicated by Specific Steam Consumption (SSC) net in relation to wet bulb temperature fluctuation from 9°C up to 20.5°C. Result shows that the existing daily operation reaches its optimum condition. The installation of Variable Frequency Drive (VFD) could be applied to optimize both utility power of HWP and CTF. The highest gain is obtained by VFD HWP installation as much as 0.80% when wet bulb temperature 18.5 °C.

  7. An Exploratory Study of Thermoelectrostatic Power Generation for Space Flight Applications

    NASA Technical Reports Server (NTRS)

    Beam, Benjamin H.

    1960-01-01

    A study has been made of a process in which a solar heating cycle is combined with an electrostatic cycle for generating electrical power for space vehicle applications. The power unit, referred to as a thermoelectrostatic generator, is a thin film, solid dielectric capacitor alternately heated by solar radiation and cooled by radiant emission. The theory of operation to extract electrical power is presented. Results of an experiment to illustrate the principle are described. Estimates of the performance of this type of device in space in the vicinity of earth are included. Values of specific power of several kilowatts per kilogram of generator weight are calculated for such a device employing polyethylene terephthalate dielectric.

  8. Trade-off study on the power capacity of a prototype SFR in Korea

    SciTech Connect

    Baek, M. H.; Kim, S. J.; Yoo, J.; Bae, I. H.

    2012-07-01

    The major roles of a prototype SFR are to provide irradiation test capability for the fuel and structure materials, and to obtain operational experiences of systems. Due to a compromise between the irradiation capability and construction costs, the power level should be properly determined. In this paper, a trade-off study on the power level of the prototype SFR was performed from a neutronics viewpoint. To select candidate cores, the parametric study of pin diameters was estimated using 20 wt.% uranium fuel. The candidate cores of different power levels, 125 MWt, 250 MWt, 400 MWt, and 500 MWt, were compared with the 1500 MWt reference core. The resulting core performance and economic efficiency indices became insensitive to the power at about 400-500 MWt and sharply deteriorated at about 125-250 MWt with decreasing core sizes. Fuel management scheme, TRU core performance comparing with uranium core, and sodium void reactivity were also evaluated with increasing power levels. It is found that increasing the number of batches showed higher burnup performance and economic efficiency. However, increasing the cycle length showed the trends in lower economic efficiency. Irradiation performance of TRU and enriched TRU cores was improved about 20 % and 50 %, respectively. The maximum sodium void reactivity of 5.2$ was confirmed less than the design limit of 7.5$. As a result, the power capacity of the prototype SFR should not be less than 250 MWt and would be appropriate at {approx} 500 MWt considering the performance and economic efficiency. (authors)

  9. Correlation of population parameters leading to power differences in association studies with population stratification.

    PubMed

    He, Y; Jiang, R; Fu, W; Bergen, A W; Swan, G E; Jin, L

    2008-11-01

    The power of statistical tests to measure effect sizes in the presence of population stratification is an important issue for the design and analysis of population-based association studies. Comparisons of statistical tests have shown that the power of different statistical approaches varies in different genetic scenarios. However, the impact of stratified population parameters on statistical power is not yet understood in a general statistical framework, particularly the impact of correlated population parameters. To investigate such impact in detail, we implemented a genetic model for population-based association studies with stratified samples and evaluated the impact on power with different genetic scenarios. The investigation shows that correlation between disease prevalence and risk allele frequency among subpopulations impacts statistical power. In a model with five subpopulations and moderate population divergence (Fst= 0.01), the correlation accounts for more than 85% of power difference. Our results also show that the estimation of genetic effect for candidate loci is biased by population divergence. Beneficial alleles could be wrongly characterized as risk alleles when prevalence differences and divergences of risk loci are large among subpopulations.

  10. A Feasibility Study of CO2-Based Rankine Cycle Powered by Solar Energy

    NASA Astrophysics Data System (ADS)

    Zhang, Xin-Rong; Yamaguchi, Hiroshi; Fujima, Katsumi; Enomoto, Masatoshi; Sawada, Noboru

    An experiment study was carried out in order to investigate feasibility of CO2-based Rankine cycle powered by solar energy. The proposed cycle is to achieve a cogeneration of heat and power, which consists of evacuated solar tube collectors, power generating turbine, heat recovery system, and feed pump. The Rankine cycle of the system utilizes solar collectors to convert CO2 into high-temperature supercritical state, used to drive a turbine and produce electrical power. The cycle also recovers thermal energy, which can be used for absorption refrigerator, air conditioning, hot water supply so on for a building. A set of experimental set-up was constructed to investigate the performance of the CO2-based Rankine cycle. The results show the cycle can achieve production of heat and power with reasonable thermodynamics efficiency and has a great potential of the application of the CO2-based Rankine cycle powered by solar energy. In addition, some research interests related to the present study will also be discussed in this paper.

  11. Power to detect clinically relevant carry-over in a series of cross-over studies.

    PubMed

    Putt, Mary E

    2006-08-15

    The potential for carry-over effects is an important consideration in the design of any cross-over study, and can cause an investigator to abandon the design altogether. In cross-over studies, carry-over is the lingering effect of a treatment into the subsequent period. Carry-over effects are differences in the extent of the carry-over between the treatments under consideration. It is well known that the test for carry-over effects in individual studies has low power. Empirical evidence of carry-over effects, or the absence of carry-over effects, could be useful for investigators considering the design. Here we develop methods for expressing the power to detect carry-over as a function of the power to detect a clinically relevant treatment effect. Our results suggest that for two-treatment, two-period cross-over studies the power to detect clinically relevant carry-over effects is often less than 15 per cent, and the number of studies needed to differentiate this effect from the type I error rate of 10 per cent is prohibitive. For the three-treatment three-period cross-over design, the power to detect carry-over effects was larger than for the two-period study, but still approached the type I error rate in a number of cases. Unequivocal conclusions about the absence of carry-over effects based on collections of hypothesis tests appear unlikely. Similar findings are presented for bioequivalence studies. For bioequivalence studies, small carry-over effects (e.g. 12.5 per cent of the treatment effect) can seriously inflate the type I error rate, particularly when the power to detect equivalence is high.

  12. Inferential Processing among Adequate and Struggling Adolescent Comprehenders and Relations to Reading Comprehension

    PubMed Central

    Barth, Amy E.; Barnes, Marcia; Francis, David J.; Vaughn, Sharon; York, Mary

    2015-01-01

    Separate mixed model analyses of variance (ANOVA) were conducted to examine the effect of textual distance on the accuracy and speed of text consistency judgments among adequate and struggling comprehenders across grades 6–12 (n = 1203). Multiple regressions examined whether accuracy in text consistency judgments uniquely accounted for variance in comprehension. Results suggest that there is considerable growth across the middle and high school years, particularly for adequate comprehenders in those text integration processes that maintain local coherence. Accuracy in text consistency judgments accounted for significant unique variance for passage-level, but not sentence-level comprehension, particularly for adequate comprehenders. PMID:26166946

  13. Using Multitheory Model of Health Behavior Change to Predict Adequate Sleep Behavior.

    PubMed

    Knowlden, Adam P; Sharma, Manoj; Nahar, Vinayak K

    The purpose of this article was to use the multitheory model of health behavior change in predicting adequate sleep behavior in college students. A valid and reliable survey was administered in a cross-sectional design (n = 151). For initiation of adequate sleep behavior, the construct of behavioral confidence (P < .001) was found to be significant and accounted for 24.4% of the variance. For sustenance of adequate sleep behavior, changes in social environment (P < .02), emotional transformation (P < .001), and practice for change (P < .001) were significant and accounted for 34.2% of the variance.

  14. Applicability of STEM-RTG and High-Power SRG Power Systems to the Discovery and Scout Mission Capabilities Expansion (DSMCE) Study of ASRG-Based Missions

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.; Cataldo, Robert L.

    2015-01-01

    This study looks at the applicability of utilizing the Segmented Thermoelectric Modular Radioisotope Thermoelectric Generator (STEM-RTG) or a high-power radioisotope generator to replace the Advanced Stirling Radioisotope Generator (ASRG), which had been identified as the baseline power system for a number of planetary exploration mission studies. Nine different Discovery-Class missions were examined to determine the applicability of either the STEM-RTG or the high-power SRG power systems in replacing the ASRG. The nine missions covered exploration across the solar system and included orbiting spacecraft, landers and rovers. Based on the evaluation a ranking of the applicability of each alternate power system to the proposed missions was made.

  15. Factors associated with adequate weekly reporting for disease surveillance data among health facilities in Nairobi County, Kenya, 2013

    PubMed Central

    Mwatondo, Athman Juma; Ng'ang'a, Zipporah; Maina, Caroline; Makayotto, Lyndah; Mwangi, Moses; Njeru, Ian; Arvelo, Wences

    2016-01-01

    Introduction Kenya adopted the Integrated Disease Surveillance and Response (IDSR) strategy in 1998 to strengthen disease surveillance and epidemic response. However, the goal of weekly surveillance reporting among health facilities has not been achieved. We conducted a cross-sectional study to determine the prevalence of adequate reporting and factors associated with IDSR reporting among health facilities in one Kenyan County. Methods Health facilities (public and private) were enrolled using stratified random sampling from 348 facilities prioritized for routine surveillance reporting. Adequately-reporting facilities were defined as those which submitted >10 weekly reports during a twelve-week period and a poor reporting facilities were those which submitted <10 weekly reports. Multivariate logistic regression with backward selection was used to identify risk factors associated with adequate reporting. Results From September 2 through November 30, 2013, we enrolled 175 health facilities; 130(74%) were private and 45(26%) were public. Of the 175 health facilities, 77 (44%) facilities classified as adequate reporting and 98 (56%) were reporting poorly. Multivariate analysis identified three factors to be independently associated with weekly adequate reporting: having weekly reporting forms at visit (AOR19, 95% CI: 6-65], having posters showing IDSR functions (AOR8, 95% CI: 2-12) and having a designated surveillance focal person (AOR7, 95% CI: 2-20). Conclusion The majority of health facilities in Nairobi County were reporting poorly to IDSR and we recommend that the Ministry of Health provide all health facilities in Nairobi County with weekly reporting tools and offer specific trainings on IDSR which will help designate a focal surveillance person. PMID:27303581

  16. Satellite Power Systems /SPS/ - Overview of system studies and critical technology

    NASA Technical Reports Server (NTRS)

    Manson, S. V.

    1980-01-01

    Systems studies and critical technology issues for the development and evaluation of Satellite Power Systems (SPS) for the photovoltaic generation of electrical energy and its transmission to earth are reviewed. Initial concept studies completed in 1976 and system definition studies initiated in the same year have indicated the technical feasibility of SPS and identified challenging issues to be addressed as part of the SPS Concept Development and Evaluation Program. Systems considered in the study include photovoltaic and solar thermal power conversion configurations employing klystron or solid state microwave generators or lasers for power transmission, and power transmission options, system constructability and in-orbit and ground operations. Technology investigations are being performed in the areas of microwave power transmission, structure/controls interactions and the behavior of key materials in the space/SPS environment. Favorable results have been obtained in the areas of microwave phase distribution and phase control, dc-RF conversion, antenna radiating element, and no insurmountable problems have been discovered in any of the investigations to date.

  17. Powerful and Cost-Efficient Designs for Longitudinal Intervention Studies with Two Treatment Groups

    ERIC Educational Resources Information Center

    Moerbeek, Mirjam

    2008-01-01

    Three issues need to be decided in the design stage of a longitudinal intervention study: the number of persons, the number of repeated measurements per person, and the duration of the study. The degree to which polynomial effects vary across persons and the drop-out pattern also influence the statistical power to detect intervention effects. This…

  18. From Black Power to Black Studies: How a Radical Social Movement became an Academic Discipline

    ERIC Educational Resources Information Center

    Rojas, Fabio

    2007-01-01

    The black power movement helped redefine African Americans' identity and establish a new racial consciousness in the 1960s. As an influential political force, this movement in turn spawned the academic discipline known as Black Studies. Today there are more than a hundred Black Studies degree programs in the United States, many of them located in…

  19. Miniaturized Power Processing Unit Study: A Cubesat Electric Propulsion Technology Enabler Project

    NASA Technical Reports Server (NTRS)

    Ghassemieh, Shakib M.

    2014-01-01

    This study evaluates High Voltage Power Processing Unit (PPU) technology and driving requirements necessary to enable the Microfluidic Electric Propulsion technology research and development by NASA and university partners. This study provides an overview of the state of the art PPU technology with recommendations for technology demonstration projects and missions for NASA to pursue.

  20. Prospective power calculations for the Four Lab study of a multigenerational reproductive/developmental toxicity rodent bioassay using a complex mixture of disinfection by-products in the low-response region.

    PubMed

    Dingus, Cheryl A; Teuschler, Linda K; Rice, Glenn E; Simmons, Jane Ellen; Narotsky, Michael G

    2011-10-01

    In complex mixture toxicology, there is growing emphasis on testing environmentally representative doses that improve the relevance of results for health risk assessment, but are typically much lower than those used in traditional toxicology studies. Traditional experimental designs with typical sample sizes may have insufficient statistical power to detect effects caused by environmentally relevant doses. Proper study design, with adequate statistical power, is critical to ensuring that experimental results are useful for environmental health risk assessment. Studies with environmentally realistic complex mixtures have practical constraints on sample concentration factor and sample volume as well as the number of animals that can be accommodated. This article describes methodology for calculation of statistical power for non-independent observations for a multigenerational rodent reproductive/developmental bioassay. The use of the methodology is illustrated using the U.S. EPA's Four Lab study in which rodents were exposed to chlorinated water concentrates containing complex mixtures of drinking water disinfection by-products. Possible experimental designs included two single-block designs and a two-block design. Considering the possible study designs and constraints, a design of two blocks of 100 females with a 40:60 ratio of control:treated animals and a significance level of 0.05 yielded maximum prospective power (~90%) to detect pup weight decreases, while providing the most power to detect increased prenatal loss.