WorldWideScience

Sample records for significantly higher power

  1. Soft Power and Higher Education: An Examination of China's Confucius Institutes

    Science.gov (United States)

    Yang, Rui

    2010-01-01

    China's global presence has become a significant subject. However, little attention has been directed to the role of higher education in projecting China's soft power, and little academic work has been done directly on it, despite the fact that there has been some work on related topics. Borrowing the theories of soft power and higher education…

  2. Corruption Significantly Increases the Capital Cost of Power Plants in Developing Contexts

    Directory of Open Access Journals (Sweden)

    Kumar Biswajit Debnath

    2018-03-01

    Full Text Available Emerging economies with rapidly growing population and energy demand, own some of the most expensive power plants in the world. We hypothesized that corruption has a relationship with the capital cost of power plants in developing countries such as Bangladesh. For this study, we analyzed the capital cost of 61 operational and planned power plants in Bangladesh. Initial comparison study revealed that the mean capital cost of a power plant in Bangladesh is twice than that of the global average. Then, the statistical analysis revealed a significant correlation between corruption and the cost of power plants, indicating that higher corruption leads to greater capital cost. The high up-front cost can be a significant burden on the economy, at present and in the future, as most are financed through international loans with extended repayment terms. There is, therefore, an urgent need for the review of the procurement and due diligence process of establishing power plants, and for the implementation of a more transparent system to mitigate adverse effects of corruption on megaprojects.

  3. Drug addiction, love, and the higher power.

    Science.gov (United States)

    Sussman, Steve; Reynaud, Michel; Aubin, Henri-Jean; Leventhal, Adam M

    2011-09-01

    This discussion piece suggests that reliance on a Higher Power in drug abuse recovery programs is entertained among some addicts for its psychobiological effects. Prayer, meditation, early romantic love, and drug abuse may have in common activation of mesolimbic dopaminergic pathways of the brain and the generation of intense emotional states. In this sense, reliance on a Higher Power may operate as a substitute addiction, which replaces the psychobiological functions formerly served by drug use. Implications of this perspective are discussed.

  4. Extension of Tom Booth's Modified Power Method for Higher Eigen Modes

    International Nuclear Information System (INIS)

    Zhang, Peng; Lee, Hyunsuk; Lee, Deokjung

    2015-01-01

    A possible technique to get the even higher modes is suggested, but it is difficult to be applied practically. In this paper, a general solution strategy is proposed, which can extend Tom Booth's modified power method to get the higher Eigenmodes and there is no limitation about the number of Eigenmodes that can be obtained with this method. In this paper, a general solution strategy is proposed, which can extend Tom Booth's modified power method to get the higher Eigenmodes and there is no limitation about the number of Eigenmodes that can be obtained with this method. It is more practical than the original solution strategy that Tom Booth proposed. The implementation of the method in Monte Carlo code shows significant advantages comparing to the original power method

  5. TRIGA research reactors with higher power density

    International Nuclear Information System (INIS)

    Whittemore, W.L.

    1994-01-01

    The recent trend in new or upgraded research reactors is to higher power densities (hence higher neutron flux levels) but not necessarily to higher power levels. The TRIGA LEU fuel with burnable poison is available in small diameter fuel rods capable of high power per rod (≅48 kW/rod) with acceptable peak fuel temperatures. The performance of a 10-MW research reactor with a compact core of hexagonal TRIGA fuel clusters has been calculated in detail. With its light water coolant, beryllium and D 2 O reflector regions, this reactor can provide in-core experiments with thermal fluxes in excess of 3 x 10 14 n/cm 2 ·s and fast fluxes (>0.1 MeV) of 2 x 10 14 n/cm 2 ·s. The core centerline thermal neutron flux in the D 2 O reflector is about 2 x 10 14 n/cm 2 ·s and the average core power density is about 230 kW/liter. Using other TRIGA fuel developed for 25-MW test reactors but arranged in hexagonal arrays, power densities in excess of 300 kW/liter are readily available. A core with TRIGA fuel operating at 15-MW and generating such a power density is capable of producing thermal neutron fluxes in a D 2 O reflector of 3 x 10 14 n/cm 2 ·s. A beryllium-filled central region of the core can further enhance the core leakage and hence the neutron flux in the reflector. (author)

  6. A general solution strategy of modified power method for higher mode solutions

    International Nuclear Information System (INIS)

    Zhang, Peng; Lee, Hyunsuk; Lee, Deokjung

    2016-01-01

    A general solution strategy of the modified power iteration method for calculating higher eigenmodes has been developed and applied in continuous energy Monte Carlo simulation. The new approach adopts four features: 1) the eigen decomposition of transfer matrix, 2) weight cancellation for higher modes, 3) population control with higher mode weights, and 4) stabilization technique of statistical fluctuations using multi-cycle accumulations. The numerical tests of neutron transport eigenvalue problems successfully demonstrate that the new strategy can significantly accelerate the fission source convergence with stable convergence behavior while obtaining multiple higher eigenmodes at the same time. The advantages of the new strategy can be summarized as 1) the replacement of the cumbersome solution step of high order polynomial equations required by Booth's original method with the simple matrix eigen decomposition, 2) faster fission source convergence in inactive cycles, 3) more stable behaviors in both inactive and active cycles, and 4) smaller variances in active cycles. Advantages 3 and 4 can be attributed to the lower sensitivity of the new strategy to statistical fluctuations due to the multi-cycle accumulations. The application of the modified power method to continuous energy Monte Carlo simulation and the higher eigenmodes up to 4th order are reported for the first time in this paper. -- Graphical abstract: -- Highlights: •Modified power method is applied to continuous energy Monte Carlo simulation. •Transfer matrix is introduced to generalize the modified power method. •All mode based population control is applied to get the higher eigenmodes. •Statistic fluctuation can be greatly reduced using accumulated tally results. •Fission source convergence is accelerated with higher mode solutions.

  7. Swiss solar power statistics 2007 - Significant expansion

    International Nuclear Information System (INIS)

    Hostettler, T.

    2008-01-01

    This article presents and discusses the 2007 statistics for solar power in Switzerland. A significant number of new installations is noted as is the high production figures from newer installations. The basics behind the compilation of the Swiss solar power statistics are briefly reviewed and an overview for the period 1989 to 2007 is presented which includes figures on the number of photovoltaic plant in service and installed peak power. Typical production figures in kilowatt-hours (kWh) per installed kilowatt-peak power (kWp) are presented and discussed for installations of various sizes. Increased production after inverter replacement in older installations is noted. Finally, the general political situation in Switzerland as far as solar power is concerned are briefly discussed as are international developments.

  8. Money, Power, Equity and Higher Education

    Directory of Open Access Journals (Sweden)

    Seyed Ali Enjoo

    2018-03-01

    Full Text Available In current issue of the Journal of Medical Education, Afshar in the Editorial “The Role of Private Sector in Higher Education; From Quantity and Quality to Access and Social Justice” proposed the importance of justice and quality. (1 It seems that there are some differences between two typesof private sector in higher education. One type of private financial support in higher education comes purely from private sector without any contribution of public sector. The second type of private finance in the higher education especially the type which has grown recently in Iranianhigher education is a type of combination between public higher education and private sector the so called international branch of the university till recent years, and nowadays called selfgoverning campus of the university. (2 In this type of private contribution to public higher education those who have no or little money must pass very hard national examination to be accepted in the university, and those who can pay the tuition fee could enter to the best schools of that university without the exam (in the firstyear of the project or by loose standards or lower cut off scores. Actually, this is an instance of the double standards.One of the elements of being equitable and avoiding discrimination is to prevent undue achievement by the owners of the power such as owners of political, religious, economic, or military power, and to avoid any distinction according to race, colour, sex, language, and etc. (3 In this type ofprivate money absorption in the higher education, while the others have no extra way to enter to the university that would lead to achievement of scientific power, the owners of the economic powers’ daughters and sons could have a special chance to achieve scientific power by the powerof their parents, and there is a different criterion to enter the university based on non-scientific differences.In such situation growing student movements against

  9. Radio frequency plasma nitriding of aluminium at higher power levels

    International Nuclear Information System (INIS)

    Gredelj, Sabina; Kumar, Sunil; Gerson, Andrea R.; Cavallaro, Giuseppe P.

    2006-01-01

    Nitriding of aluminium 2011 using a radio frequency plasma at higher power levels (500 and 700 W) and lower substrate temperature (500 deg. C) resulted in higher AlN/Al 2 O 3 ratios than obtained at 100 W and 575 deg. C. AlN/Al 2 O 3 ratios derived from X-ray photoelectron spectroscopic analysis (and corroborated by heavy ion elastic recoil time of flight spectrometry) for treatments preformed at 100 (575 deg. C), 500 (500 deg. C) and 700 W (500 deg. C) were 1.0, 1.5 and 3.3, respectively. Scanning electron microscopy revealed that plasma nitrided surfaces obtained at higher power levels exhibited much finer nodular morphology than obtained at 100 W

  10. Economic Operation of Power Systems with Significant Wind Power Penetration

    DEFF Research Database (Denmark)

    Farashbashi-Astaneh, Seyed-Mostafa

    This dissertation addresses economic operation of power systems with high penetration of wind power. Several studies are presented to address the economic operation of power systems with high penetration of variable wind power. The main concern in such power systems is high variability...... and unpredictability. Unlike conventional power plants, the output power of a wind farm is not controllable. This brings additional complexity to operation and planning of wind dominant power systems. The key solution in face of wind power uncertainty is to enhance power system flexibility. The enhanced flexibility......, cooperative wind-storage operation is studied. Lithium-Ion battery units are chosen as storage units. A novel formulation is proposed to investigate optimal operation of a storage unit considering power system balancing conditions and wind power imbalances. An optimization framework is presented to increase...

  11. Competitive Intelligence: Significance in Higher Education

    Science.gov (United States)

    Barrett, Susan E.

    2010-01-01

    Historically noncompetitive, the higher education sector is now having to adjust dramatically to new and increasing demands on numerous levels. To remain successfully operational within the higher educational market universities today must consider all relevant forces which can impact present and future planning. Those institutions that were…

  12. Sex, Grades and Power in Higher Education in Ghana and Tanzania

    Science.gov (United States)

    Morley, Louise

    2011-01-01

    Quantitative increases tell a partial story about the quality of women's participation in higher education. Women students' reporting of sexual harassment has been noteworthy in a recent study that I directed on widening participation in higher education in Ghana and Tanzania. The hierarchical and gendered power relations within universities have…

  13. HVDC Transmission an Outlook and Significance for Pakistani Power Sector

    Science.gov (United States)

    Ahmad, Muhammad; Wang, Zhixin; Wang, Jinjian; Baloach, Mazhar H.; Longxin, Bao; Hua, Qing

    2018-04-01

    Recently a paradigm shift in the power sector is observed, i.e., countries across the globe have deviated their attention to distributed generation rather than conventional centralized bulk generation. Owing to the above narrative, distributed energy resources e.g., wind and PV have gained the adequate attention of governments and researchers courtesy to their eco-friendly nature. On the contrary, the increased infiltration of distributed generation to the power system has introduced many technical and economical glitches such as long-distance transmission, transmission lines efficiency, control capability and cost etc. To mitigate these complications, the utility of high voltage direct current (HVDC) transmission has emerged as a possible solution. In this context, this paper includes a brief discussion on the fundamentals HVDC and its significance in Pakistani power sector. Furthermore, the potential of distributed energy resources for Pakistan is also the subject matter of this paper, so that significance of HVDC transmission can effectively be deliberated.

  14. The Higher Power of Patron: Profile of Newbery Winner

    Science.gov (United States)

    Oleck, Joan

    2007-01-01

    One lousy starred review. That was all, initially, that Susan Patron had to show for the 10 years she spent writing "The Higher Power of Lucky," her funny, tender story of a little girl struggling to gain control over her life. One star, from "Kirkus Reviews," for the heart and soul Patron poured into her second novel. Positive notices had…

  15. Serum concentration of alpha-1 antitrypsin is significantly higher in colorectal cancer patients than in healthy controls

    International Nuclear Information System (INIS)

    Pérez-Holanda, Sergio; Blanco, Ignacio; Menéndez, Manuel; Rodrigo, Luis

    2014-01-01

    The association between alpha-1 antitrypsin (AAT) deficiency and colorectal cancer (CRC) is currently controversial. The present study compares AAT serum concentrations and gene frequencies between a group of CRC patients and a control group of healthy unrelated people (HUP). 267 CRC subjects (63% males, 72 ± 10 years old) were enlisted from a Hospital Clinic setting in Asturias, Spain. The HUP group comprised 327 subjects (67% males, mean age 70 ± 7.5 years old) from the same geographical region. Outcome measures were AAT serum concentrations measured by nephelometry, and AAT phenotyping characterization by isoelectric focusing. Significantly higher serum concentrations were found among CRC (208 ± 60) than in HUP individuals (144 ± 20.5) (p = 0.0001). No differences were found in the phenotypic distribution of the Pi*S and Pi*Z allelic frequencies (p = 0.639), although the frequency of Pi*Z was higher in CRC (21%) than in HUP subjects (15%). The only statistically significant finding in this study was the markedly higher AAT serum concentrations found in CRC subjects compared with HUP controls, irrespective of whether their Pi* phenotype was normal (Pi*MM) or deficient (Pi*MS, Pi*MZ and Pi*SZ). Although there was a trend towards the more deficient Pi* phenotype the more advanced the tumor, the results were inconclusive due to the small sample size. Consequently, more powerful studies are needed to reach firmer conclusions on this matter

  16. Chronic pain and praying to a higher power: useful or useless?

    Science.gov (United States)

    Andersson, Gerhard

    2008-06-01

    In the present study a Swedish sample of 118 persons with chronic pain completed online tests on two occasions in association with treatment trials. A three item subscale measuring praying as a coping strategy was derived from the Coping Strategies Questionnaire (CSQ), but adapted to refer to "a higher power" instead of "God". Measures of pain and anxiety/depression were also included. Results revealed significant associations between praying and pain interference and impairment. Praying was also associated with anxiety and depression scores. Results also showed that prayer predicted depression scores at follow-up, and that follow-up prayer was predicted by pain interference at first measurement occasion. Overall, if prayer had any relation with the other variables it was in the negative direction of more distress being associated with more praying both concurrently and prospectively.

  17. Peer Mentoring in Higher Education: Issues of Power and Control

    Science.gov (United States)

    Christie, Hazel

    2014-01-01

    In response to widespread support for mentoring schemes in higher education this article calls for a more critical investigation of the dynamics of power and control, which are intrinsic to the mentoring process, and questions presumptions that mentoring brings only positive benefits to its participants. It provides this more critical appraisal by…

  18. A shift from significance test to hypothesis test through power analysis in medical research.

    Science.gov (United States)

    Singh, G

    2006-01-01

    Medical research literature until recently, exhibited substantial dominance of the Fisher's significance test approach of statistical inference concentrating more on probability of type I error over Neyman-Pearson's hypothesis test considering both probability of type I and II error. Fisher's approach dichotomises results into significant or not significant results with a P value. The Neyman-Pearson's approach talks of acceptance or rejection of null hypothesis. Based on the same theory these two approaches deal with same objective and conclude in their own way. The advancement in computing techniques and availability of statistical software have resulted in increasing application of power calculations in medical research and thereby reporting the result of significance tests in the light of power of the test also. Significance test approach, when it incorporates power analysis contains the essence of hypothesis test approach. It may be safely argued that rising application of power analysis in medical research may have initiated a shift from Fisher's significance test to Neyman-Pearson's hypothesis test procedure.

  19. Investigation of Turkish Higher Education as a Means of Influence in Relation to ‘Soft Power'

    Directory of Open Access Journals (Sweden)

    Hilal BÜYÜKGÖZE

    2016-05-01

    Full Text Available With the realization of soft power's potential in time which was emerged by the canalization of international diplomacy conjuncture directing to new quests after the industrial revolution and cold war, states have been led to apply various ways and methods regarding their foreign policies. Turkey also utilizes soft power, defined generally as the ability to shape the preferences of others through appeal rather than coerce, both through financial co-operations, constructive applications in international policy and through national institutions, foundations and Non-Governmental Organizations for its appearance and perception in international system. Higher education, which has an international characteristic, may also be assessed as a soft power element through international students and academics. Accordingly, in the current study, power and soft power terms were investigated, and the role of soft power in Turkey's foreign policy and Turkish higher education was examined. The findings of the study showed that the strategies toward internationalism in higher education are not sufficient, academics and university students have a certain level of awareness on the issue though. The results were interpreted within the scope of the literature, and managerial and functional characteristics of Turkish higher education as well.

  20. A shift from significance test to hypothesis test through power analysis in medical research

    Directory of Open Access Journals (Sweden)

    Singh Girish

    2006-01-01

    Full Text Available Medical research literature until recently, exhibited substantial dominance of the Fisher′s significance test approach of statistical inference concentrating more on probability of type I error over Neyman-Pearson′s hypothesis test considering both probability of type I and II error. Fisher′s approach dichotomises results into significant or not significant results with a P value. The Neyman-Pearson′s approach talks of acceptance or rejection of null hypothesis. Based on the same theory these two approaches deal with same objective and conclude in their own way. The advancement in computing techniques and availability of statistical software have resulted in increasing application of power calculations in medical research and thereby reporting the result of significance tests in the light of power of the test also. Significance test approach, when it incorporates power analysis contains the essence of hypothesis test approach. It may be safely argued that rising application of power analysis in medical research may have initiated a shift from Fisher′s significance test to Neyman-Pearson′s hypothesis test procedure.

  1. The role and significance of nuclear power in China in response to climate change

    International Nuclear Information System (INIS)

    Hou Huiqun; Wu Jin; Bai Yunsheng

    2010-01-01

    This paper analyzes international climate negotiations and the domestic situation. In accordance with the development goal of 2020, the emission reduction of nuclear power is measured as compared with thermal power from the sector of power generation and nuclear power chain respectively. It emphasized that nuclear power can play a significant role in the emission reduction with corresponding policy recommendations. (authors)

  2. Attachment to God/Higher Power and Bulimic Symptoms among College Women

    Science.gov (United States)

    Buser, Juleen K.; Gibson, Sandy

    2016-01-01

    The authors examined the relationship between avoidant and anxious attachment to God/Higher Power and bulimia symptoms among 599 female college student participants. After controlling for body mass index, the authors found a positive association between both attachment variables and bulimia. When entered together in a regression, anxious…

  3. A fast method for the unit scheduling problem with significant renewable power generation

    International Nuclear Information System (INIS)

    Osório, G.J.; Lujano-Rojas, J.M.; Matias, J.C.O.; Catalão, J.P.S.

    2015-01-01

    Highlights: • A model to the scheduling of power systems with significant renewable power generation is provided. • A new methodology that takes information from the analysis of each scenario separately is proposed. • Based on a probabilistic analysis, unit scheduling and corresponding economic dispatch are estimated. • A comparison with others methodologies is in favour of the proposed approach. - Abstract: Optimal operation of power systems with high integration of renewable power sources has become difficult as a consequence of the random nature of some sources like wind energy and photovoltaic energy. Nowadays, this problem is solved using Monte Carlo Simulation (MCS) approach, which allows considering important statistical characteristics of wind and solar power production such as the correlation between consecutive observations, the diurnal profile of the forecasted power production, and the forecasting error. However, MCS method requires the analysis of a representative amount of trials, which is an intensive calculation task that increases considerably with the number of scenarios considered. In this paper, a model to the scheduling of power systems with significant renewable power generation based on scenario generation/reduction method, which establishes a proportional relationship between the number of scenarios and the computational time required to analyse them, is proposed. The methodology takes information from the analysis of each scenario separately to determine the probabilistic behaviour of each generator at each hour in the scheduling problem. Then, considering a determined significance level, the units to be committed are selected and the load dispatch is determined. The proposed technique was illustrated through a case study and the comparison with stochastic programming approach was carried out, concluding that the proposed methodology can provide an acceptable solution in a reduced computational time

  4. Analysing the significance of silence in qualitative interviewing: questioning and shifting power relations

    DEFF Research Database (Denmark)

    Bengtsson, Tea Torbenfeldt; Fynbo, Lars

    2017-01-01

    In this article we analyse the significance of silence in qualitative interviews with 36 individuals interviewed about high-risk, illegal activities. We describe how silence expresses a dynamic power relationship between interviewer and interviewee. In the analysis, we focus on two different types...... significant data. We conclude that silence constitutes possibilities for interviewees and interviewers to handle the complex power at play in qualitative interviewing either by maintaining or by losing control of the situation....

  5. Significant change of predictions related to the future of nuclear power

    International Nuclear Information System (INIS)

    Dumitrache, Ion

    2002-01-01

    During the last two decades of the 20th century, nuclear power contribution increased slowly in the world. This trend was mainly determined by the commissioning of new nuclear power plants, NPP, in the non-developed countries, except for Japan and South Korea. Almost all the forecasts offered the image of the stagnant nuclear power business. Sweden, Germany, Holland and Belgium Governments made clear the intention to stop the production of electricity based on fission. Recently, despite the negative effects on nuclear power of the terrorism events of September 11, 2001, the predictions related to the nuclear power future become much more optimistic. USA, Japan, South Korea and Canada made clear that new NPPs will offer their significant electricity contribution several decades, even after years 2020-2030. Moreover, several old NPP from USA obtained the license for an additional 20 years period of operation. The analysis indicated that most of the existing NPP in USA may increase the level of the maximum global power defined by the initial design. In the European Union the situation is much more complicated. About 35% of the electricity is based now on fission. Several countries, like Sweden and Germany, maintain the position of phasing out the NPPs, as soon as the licensed life-time is over. Finland decided to build a new power plant. France is very favorable to nuclear power, but does not need more energy. In the UK several very old NPP will be shut down, and companies like BNFL and British Energy intend to build new NPP, based on Westinghouse or AECL-Canada advanced reactors. Switzerland and Spain are favorable to the future use of nuclear power. In the eastern part of Europe, almost all the countries intend to base their electricity production on coal, fission, hydro and gas, nuclear contribution being significant. The most impressive increases of nuclear power output are related to Asia; in China, from 2.2 Gwe in 1999, to 18.7 Gwe in 2020, reference case, or 10

  6. Power-law scaling of extreme dynamics near higher-order exceptional points

    Science.gov (United States)

    Zhong, Q.; Christodoulides, D. N.; Khajavikhan, M.; Makris, K. G.; El-Ganainy, R.

    2018-02-01

    We investigate the extreme dynamics of non-Hermitian systems near higher-order exceptional points in photonic networks constructed using the bosonic algebra method. We show that strong power oscillations for certain initial conditions can occur as a result of the peculiar eigenspace geometry and its dimensionality collapse near these singularities. By using complementary numerical and analytical approaches, we show that, in the parity-time (PT ) phase near exceptional points, the logarithm of the maximum optical power amplification scales linearly with the order of the exceptional point. We focus in our discussion on photonic systems, but we note that our results apply to other physical systems as well.

  7. The power of non-determinism in higher-order implicit complexity

    DEFF Research Database (Denmark)

    Kop, Cynthia Louisa Martina; Simonsen, Jakob Grue

    2017-01-01

    We investigate the power of non-determinism in purely functional programming languages with higher-order types. Specifically, we consider cons-free programs of varying data orders, equipped with explicit non-deterministic choice. Cons-freeness roughly means that data constructors cannot occur...... in function bodies and all manipulation of storage space thus has to happen indirectly using the call stack. While cons-free programs have previously been used by several authors to characterise complexity classes, the work on non-deterministic programs has almost exclusively considered programs of data order...... 0. Previous work has shown that adding explicit non-determinism to consfree programs taking data of order 0 does not increase expressivity; we prove that this—dramatically—is not the case for higher data orders: adding non-determinism to programs with data order at least 1 allows...

  8. Experimental Demonstration of Higher Precision Weak-Value-Based Metrology Using Power Recycling

    Science.gov (United States)

    Wang, Yi-Tao; Tang, Jian-Shun; Hu, Gang; Wang, Jian; Yu, Shang; Zhou, Zong-Quan; Cheng, Ze-Di; Xu, Jin-Shi; Fang, Sen-Zhi; Wu, Qing-Lin; Li, Chuan-Feng; Guo, Guang-Can

    2016-12-01

    The weak-value-based metrology is very promising and has attracted a lot of attention in recent years because of its remarkable ability in signal amplification. However, it is suggested that the upper limit of the precision of this metrology cannot exceed that of classical metrology because of the low sample size caused by the probe loss during postselection. Nevertheless, a recent proposal shows that this probe loss can be reduced by the power-recycling technique, and thus enhance the precision of weak-value-based metrology. Here we experimentally realize the power-recycled interferometric weak-value-based beam-deflection measurement and obtain the amplitude of the detected signal and white noise by discrete Fourier transform. Our results show that the detected signal can be strengthened by power recycling, and the power-recycled weak-value-based signal-to-noise ratio can surpass the upper limit of the classical scheme, corresponding to the shot-noise limit. This work sheds light on higher precision metrology and explores the real advantage of the weak-value-based metrology over classical metrology.

  9. Electric power and its significance as the energy for innovation and progress

    International Nuclear Information System (INIS)

    Klinger, H.; Boehmer, T.

    1999-01-01

    The significance of electric power as the essential form of energy to support innovation and progress well into the future is explained with respect to four major domains of application: 1. Innovative activities in microelectronics and semiconductor technology, for applications such as automation and computer technology, instrumentation and control technology, facility and systems management and control. 2. Energy efficiency programmes and schemes for increasing the penetration of energiy from renewable sources in the market. Example: Heat pump technology. 3. Electric power as an energy boosting innovation in industrial production processes. Examples are given from the transportation sector. (orig./CB) [de

  10. Higher-order-mode (HOM) power in elliptical superconducting cavities for intense pulsed proton accelerators

    CERN Document Server

    Sang Ho Kim; Dong O Jeon; Sundeli, R

    2002-01-01

    In linacs for intense pulsed proton accelerators, the beam has a multiple time-structure, and each beam time-structure generates resonance. When a higher-order mode (HOM) is near these resonance frequencies, the induced voltage could be large and accordingly the resulting HOM power, too. In order to understand the effects of a complex beam time-structure on the mode excitations and the resulting HOM powers in elliptical superconducting cavities, analytic expressions are developed, with which the beam-induced voltage and corresponding power are explored, taking into account the properties of HOM frequency behavior in elliptical superconducting cavities. The results and understandings from this analysis are presented with the beam parameters of the Spallation Neutron Source (SNS) superconducting linac.

  11. 75 FR 11575 - James A. Fitzpatrick Nuclear Power Plant Environmental Assessment and Finding of No Significant...

    Science.gov (United States)

    2010-03-11

    ... Power Plant Environmental Assessment and Finding of No Significant Impact The U.S. Nuclear Regulatory...), for the operation of the James A. FitzPatrick Nuclear Power Plant (JAFNPP) located in Oswego County... the Final Environmental Statement for the James A. FitzPatrick Nuclear Power Plant, Docket No. 50-333...

  12. A Note on Comparing the Power of Test Statistics at Low Significance Levels.

    Science.gov (United States)

    Morris, Nathan; Elston, Robert

    2011-01-01

    It is an obvious fact that the power of a test statistic is dependent upon the significance (alpha) level at which the test is performed. It is perhaps a less obvious fact that the relative performance of two statistics in terms of power is also a function of the alpha level. Through numerous personal discussions, we have noted that even some competent statisticians have the mistaken intuition that relative power comparisons at traditional levels such as α = 0.05 will be roughly similar to relative power comparisons at very low levels, such as the level α = 5 × 10 -8 , which is commonly used in genome-wide association studies. In this brief note, we demonstrate that this notion is in fact quite wrong, especially with respect to comparing tests with differing degrees of freedom. In fact, at very low alpha levels the cost of additional degrees of freedom is often comparatively low. Thus we recommend that statisticians exercise caution when interpreting the results of power comparison studies which use alpha levels that will not be used in practice.

  13. A Dialogue between Partnership and Feminism: Deconstructing Power and Exclusion in Higher Education

    Science.gov (United States)

    Mercer-Mapstone, Lucy; Mercer, Gina

    2018-01-01

    Students as partners (SaP) has seen an increase in focus as an area of active student engagement in higher education. Many complexities and challenges have been shared in this evolving field regarding inclusivity and power. We discuss, in this dialogue, insights that can be uncovered by exploring SaP through a feminist lens--illuminating the fact…

  14. Research and higher education background of the Paks Nuclear Power Plant, Hungary. Past and present

    International Nuclear Information System (INIS)

    Csom, Gy.

    2002-01-01

    The connection of the Paks Nuclear Power Plant, Hungary, with research and development as well as with higher education is discussed. The main research areas include reactor physics, thermohydraulics, radiochemistry and radiochemical analysis, electronics and nuclear instruments, computers, materials science. The evolution of relations with higher education in Hungary and the PNPP is presented, before and after the installation of the various units. (R.P.)

  15. Eigenstates of the higher power of the annihilation operator of two-parameter deformed harmonic oscillator

    International Nuclear Information System (INIS)

    Wang Jisuo; Sun Changyong; He Jinyu

    1996-01-01

    The eigenstates of the higher power of the annihilation operator a qs k (k≥3) of the two-parameter deformed harmonic oscillator are constructed. Their completeness is demonstrated in terms of the qs-integration

  16. The significance of structural power in Strategic Environmental Assessment

    International Nuclear Information System (INIS)

    Hansen, Anne Merrild; Kørnøv, Lone; Cashmore, Matthew; Richardson, Tim

    2013-01-01

    This article presents a study of how power dynamics enables and constrains the influence of actors upon decision-making and Strategic Environmental Assessment (SEA). Based on structuration theory, a model for studying power dynamics in strategic decision-making processes is developed. The model is used to map and analyse key decision arenas in the decision process of aluminium production in Greenland. The analysis shows that communication lines are an important resource through which actors exercise power and influence decision-making on the location of the aluminium production. The SEA process involved not only reproduction of formal communication and decision competence but also production of alternative informal communication structures in which the SEA had capability to influence. It is concluded, that actors influence strategic decision making, and attention needs to be on not only the formal interactions between SEA process and strategic decision-making process but also on informal interaction and communication between actors as the informal structures, which can be crucial to the outcome of the decision-making process. This article is meant as a supplement to the understanding of power dynamics influence in IA processes and as a contribution to the IA research field with a method to analyse power dynamics in strategic decision-making processes. The article also brings reflections of strengths and weaknesses of using the structuration theory as an approach to power analysis. - Highlights: ► Informal interaction influenced process despite the presence of formalised rules. ► Interdependence of actors influenced SEA effectiveness. ► SEA practitioners successfully exercised power to influence decision-making. ► Power dynamics are properties of actors' interactions in decision-making. ► Power structures can be enabling and not solely limiting.

  17. A critical discussion of null hypothesis significance testing and statistical power analysis within psychological research

    DEFF Research Database (Denmark)

    Jones, Allan; Sommerlund, Bo

    2007-01-01

    The uses of null hypothesis significance testing (NHST) and statistical power analysis within psychological research are critically discussed. The article looks at the problems of relying solely on NHST when dealing with small and large sample sizes. The use of power-analysis in estimating...... the potential error introduced by small and large samples is advocated. Power analysis is not recommended as a replacement to NHST but as an additional source of information about the phenomena under investigation. Moreover, the importance of conceptual analysis in relation to statistical analysis of hypothesis...

  18. Power Distance in Online Learning: Experience of Chinese Learners in U.S. Higher Education

    Science.gov (United States)

    Zhang, Yi (Leaf)

    2013-01-01

    The purpose of this research study was to explore the influence of Confucian-heritage culture on Chinese learners' online learning and engagement in online discussion in U.S. higher education. More specifically, this research studied Chinese learners' perceptions of power distance and its impact on their interactions with instructors and peers in…

  19. Power, effects, confidence, and significance: an investigation of statistical practices in nursing research.

    Science.gov (United States)

    Gaskin, Cadeyrn J; Happell, Brenda

    2014-05-01

    improvement. Most importantly, researchers should abandon the misleading practice of interpreting the results from inferential tests based solely on whether they are statistically significant (or not) and, instead, focus on reporting and interpreting effect sizes, confidence intervals, and significance levels. Nursing researchers also need to conduct and report a priori power analyses, and to address the issue of Type I experiment-wise error inflation in their studies. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  20. Development of a higher power cooling system for lithium targets.

    Science.gov (United States)

    Phoenix, B; Green, S; Scott, M C; Bennett, J R J; Edgecock, T R

    2015-12-01

    The accelerator based Boron Neutron Capture Therapy beam at the University of Birmingham is based around a solid thick lithium target cooled by heavy water. Significant upgrades to Birmingham's Dynamitron accelerator are planned prior to commencing a clinical trial. These upgrades will result in an increase in maximum achievable beam current to at least 3 mA. Various upgrades to the target cooling system to cope with this increased power have been investigated. Tests of a phase change coolant known as "binary ice" have been carried out using an induction heater to provide a comparable power input to the Dynamitron beam. The experimental data shows no improvement over chilled water in the submerged jet system, with both systems exhibiting the same heat input to target temperature relation for a given flow rate. The relationship between the cooling circuit pumping rate and the target temperature in the submerged jet system has also been tested. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. The significance of structural power in Strategic Environmental Assessment

    DEFF Research Database (Denmark)

    Hansen, Anne Merrild; Kørnøv, Lone; Cashmore, Matthew Asa

    2013-01-01

    , that actors influence both outcome and frames for strategic decision making and attention needs to be on not only the formal interactions between SEA process and strategic decision-making process but also on informal interaction and communication between actors. The informal structures shows crucial...... to the outcome of the decision-making process. The article is meant as a supplement to the understanding of power dynamics influence in IA processes emphasising the capacity of agents to mobilise and create change. Despite epistemological challenges of using ST theory as an approach to power analysis, this meta......This article presents a study of how power dynamics enables and constrains the influence of actors upon decision-making and Strategic Environmental Assessment (SEA). Based on Anthony Giddens structuration theory (ST), a model for studying power dynamics in strategic decision-making processes...

  2. Analysis of Expediency to Apply LCL Model with Source of Higher Harmonics of Current While Investigating Resonance Condition of Power Supply Network

    OpenAIRE

    M. Pavlovsky; A. Shimansky; Z. Fialkovsky

    2004-01-01

    The paper considers a power system model of a plant with one capacitor bank and with one current source of higher harmonics for higher power factor. The laboratory research results of this system and practical application of the proposed model are given in the paper.

  3. Analysis of events significant with regard to safety of Bohunice V-1 nuclear power plant

    International Nuclear Information System (INIS)

    Suchomel, J.; Maron, V.; Kmosena, J.

    1986-01-01

    An analysis was made of operating safety of the V-1 nuclear power plant in Jaslovske Bohunice for the years 1980 - 1983. Of the total number of 676 reported failures only three were events with special safety significance, namely a complete loss of power supply for own consumption from the power grid, a failure of pins on the collectors of steam generators, and a failure of the heads of heat technology inspection channels. The failures were categorized according to the systems used in the USSR and in the USA and compared with data on failures in nuclear power plants in the two countries. The conclusions show that the operation of the V-1 nuclear power plant achieves results which are fully comparable with those recorded in 9 WWER-440 power plants operating in various countries. The average coefficient of availability is 0.72 and ranks the power plant in the fourth place among the said 9 plants. A comparison of the individual power plant units showed that of the total number of 22, the first unit of the V-1 plant ranks fifth with a coefficient of 0.78 and the second unit with a coefficient of 0.69 ranks 15th. (Z.M.)

  4. Capturing power at higher voltages from arrays of microbial fuel cells without voltage reversal

    KAUST Repository

    Kim, Younggy

    2011-01-01

    Voltages produced by microbial fuel cells (MFCs) cannot be sustainably increased by linking them in series due to voltage reversal, which substantially reduces stack voltages. It was shown here that MFC voltages can be increased with continuous power production using an electronic circuit containing two sets of multiple capacitors that were alternately charged and discharged (every one second). Capacitors were charged in parallel by the MFCs, but linked in series while discharging to the circuit load (resistor). The parallel charging of the capacitors avoided voltage reversal, while discharging the capacitors in series produced up to 2.5 V with four capacitors. There were negligible energy losses in the circuit compared to 20-40% losses typically obtained with MFCs using DC-DC converters to increase voltage. Coulombic efficiencies were 67% when power was generated via four capacitors, compared to only 38% when individual MFCs were operated with a fixed resistance of 250 Ω. The maximum power produced using the capacitors was not adversely affected by variable performance of the MFCs, showing that power generation can be maintained even if individual MFCs perform differently. Longer capacitor charging and discharging cycles of up to 4 min maintained the average power but increased peak power by up to 2.6 times. These results show that capacitors can be used to easily obtain higher voltages from MFCs, allowing for more useful capture of energy from arrays of MFCs. © 2011 The Royal Society of Chemistry.

  5. Analysis of Expediency to Apply LCL Model with Source of Higher Harmonics of Current While Investigating Resonance Condition of Power Supply Network

    Directory of Open Access Journals (Sweden)

    M. Pavlovsky

    2004-01-01

    Full Text Available The paper considers a power system model of a plant with one capacitor bank and with one current source of higher harmonics for higher power factor. The laboratory research results of this system and practical application of the proposed model are given in the paper.

  6. Method of extracting significant trouble information of nuclear power plants using probabilistic analysis technique

    International Nuclear Information System (INIS)

    Shimada, Yoshio; Miyazaki, Takamasa

    2005-01-01

    In order to analyze and evaluate large amounts of trouble information of overseas nuclear power plants, it is necessary to select information that is significant in terms of both safety and reliability. In this research, a method of efficiently and simply classifying degrees of importance of components in terms of safety and reliability while paying attention to root-cause components appearing in the information was developed. Regarding safety, the reactor core damage frequency (CDF), which is used in the probabilistic analysis of a reactor, was used. Regarding reliability, the automatic plant trip probability (APTP), which is used in the probabilistic analysis of automatic reactor trips, was used. These two aspects were reflected in the development of criteria for classifying degrees of importance of components. By applying these criteria, a simple method of extracting significant trouble information of overseas nuclear power plants was developed. (author)

  7. Planning for Higher Oil Prices : Power Sector Impact in Latin America and the Caribbean

    OpenAIRE

    Yépez-García, Rigoberto Ariel; San Vicente Portes, Luis; García, Luis Enrique

    2013-01-01

    A scenario with higher oil prices has important implications for diverting from oil-based technologies to renewables, as well as gas, coal, and nuclear alternatives. By 2030, energy demand in Latin America and the Caribbean (LAC) is expected to double from 2008 levels. A key issue is deciding on the most appropriate mix of fuels for power generation, given the various prices of energy sour...

  8. CONSIDERATIONS FOR FAILURE PREVENTION IN AEROSPACE ELECTRICAL POWER SYSTEMS UTILIZING HIGHER VOLTAGES

    Science.gov (United States)

    2017-07-01

    exist to develop tests that mimic the aerospace environment. Testing and qualification requirements for hermetic components need to consider leakage ...containing significant amounts of water . Different parts of the flight cycle may also be critical for specific components. Open-box power electronics...60270 [A-3]. Specialized test systems have been developed to detect and characterize PD in electrical equipment at atmospheric pressures. Although

  9. Power generation statistics

    International Nuclear Information System (INIS)

    Kangas, H.

    2001-01-01

    The frost in February increased the power demand in Finland significantly. The total power consumption in Finland during January-February 2001 was about 4% higher than a year before. In January 2001 the average temperature in Finland was only about - 4 deg C, which is nearly 2 degrees higher than in 2000 and about 6 degrees higher than long term average. Power demand in January was slightly less than 7.9 TWh, being about 0.5% less than in 2000. The power consumption in Finland during the past 12 months exceeded 79.3 TWh, which is less than 2% higher than during the previous 12 months. In February 2001 the average temperature was - 10 deg C, which was about 5 degrees lower than in February 2000. Because of this the power consumption in February 2001 increased by 5%. Power consumption in February was 7.5 TWh. The maximum hourly output of power plants in Finland was 13310 MW. Power consumption of Finnish households in February 2001 was about 10% higher than in February 2000, and in industry the increase was nearly zero. The utilization rate in forest industry in February 2001 decreased from the value of February 2000 by 5%, being only about 89%. The power consumption of the past 12 months (Feb. 2000 - Feb. 2001) was 79.6 TWh. Generation of hydroelectric power in Finland during January - February 2001 was 10% higher than a year before. The generation of hydroelectric power in Jan. - Feb. 2001 was nearly 2.7 TWh, corresponding to 17% of the power demand in Finland. The output of hydroelectric power in Finland during the past 12 months was 14.7 TWh. The increase from the previous 12 months was 17% corresponding to over 18% of the power demand in Finland. Wind power generation in Jan. - Feb. 2001 was exceeded slightly 10 GWh, while in 2000 the corresponding output was 20 GWh. The degree of utilization of Finnish nuclear power plants in Jan. - Feb. 2001 was high. The output of these plants was 3.8 TWh, being about 1% less than in Jan. - Feb. 2000. The main cause for the

  10. Safety at basic nuclear facilities other than nuclear power plants. Lessons learned from significant events reported in 2011 and 2012

    International Nuclear Information System (INIS)

    2014-01-01

    The third report on the safety of basic nuclear installations in France other than power reactors presents an IRSN's analysis of significant events reported to the Nuclear Safety Authority in the years 2011 and 2012. It covers plants, laboratories, research reactors and facilities for the treatment, storage or disposal of waste. This report aims to contribute to a better understanding by stakeholders and more widely by the public of the safety and radiation protection issues associated with the operation of nuclear facilities, the progress made in terms of safety as well as the identified deficiencies. The main trend shows, once again, the significant role of organizational and human factors in the significant events that occurred in 2011 and 2012, of which the vast majority are without noteworthy consequences. Aging mechanisms are another major cause of equipment failure and require special attention. The report also provides IRSN's analysis of specific events that are particularly instructive for facility safety and a synthesis of assessments performed by IRSN on topics that are important for safety and radiation protection. IRSN also includes an overview of its analysis of measures proposed by licensees for increasing the safety of their facilities after the March 2011 accident at the Fukushima Daiichi nuclear power plant in Japan, which consist of providing a 'hardened safety core' to confront extreme situations (earthquake, flooding, etc.) that are unlikely but plausible and can bring about levels of hazards higher than those taken into account in the design of the facilities

  11. A new hybrid nonlinear congruential number generator based on higher functional power of logistic maps

    International Nuclear Information System (INIS)

    Cecen, Songul; Demirer, R. Murat; Bayrak, Coskun

    2009-01-01

    We propose a nonlinear congruential pseudorandom number generator consisting of summation of higher order composition of random logistic maps under certain congruential mappings. We change both bifurcation parameters of logistic maps in the interval of U=[3.5599,4) and coefficients of the polynomials in each higher order composition of terms up to degree d. This helped us to obtain a perfect random decorrelated generator which is infinite and aperiodic. It is observed from the simulation results that our new PRNG has good uniformity and power spectrum properties with very flat white noise characteristics. The results are interesting, new and may have applications in cryptography and in Monte Carlo simulations.

  12. Body lift, drag and power are relatively higher in large-eared than in small-eared bat species.

    Science.gov (United States)

    Håkansson, Jonas; Jakobsen, Lasse; Hedenström, Anders; Johansson, L Christoffer

    2017-10-01

    Bats navigate the dark using echolocation. Echolocation is enhanced by external ears, but external ears increase the projected frontal area and reduce the streamlining of the animal. External ears are thus expected to compromise flight efficiency, but research suggests that very large ears may mitigate the cost by producing aerodynamic lift. Here we compare quantitative aerodynamic measures of flight efficiency of two bat species, one large-eared ( Plecotus auritus ) and one small-eared ( Glossophaga soricina ), flying freely in a wind tunnel. We find that the body drag of both species is higher than previously assumed and that the large-eared species has a higher body drag coefficient, but also produces relatively more ear/body lift than the small-eared species, in line with prior studies on model bats. The measured aerodynamic power of P. auritus was higher than predicted from the aerodynamic model, while the small-eared species aligned with predictions. The relatively higher power of the large-eared species results in lower optimal flight speeds and our findings support the notion of a trade-off between the acoustic benefits of large external ears and aerodynamic performance. The result of this trade-off would be the eco-morphological correlation in bat flight, with large-eared bats generally adopting slow-flight feeding strategies. © 2017 The Author(s).

  13. Fock representation of the renormalized higher powers of White noise and the centreless Virasoro (or Witt)-Zamolodchikov-w∞*-Lie algebra

    International Nuclear Information System (INIS)

    Accardi, Luigi; Boukas, Andreas

    2008-01-01

    The identification of the *-Lie algebra of the renormalized higher powers of White noise (RHPWN) and the analytic continuation of the second quantized centreless Virasoro (or Witt)-Zamolodchikov-w ∞ *-Lie algebra of conformal field theory and high-energy physics, was recently established on results obtained. In the present paper, we show how the RHPWN Fock kernels must be truncated in order to be positive semi-definite and we obtain a Fock representation of the two algebras. We show that the truncated renormalized higher powers of White noise (TRHPWN) Fock spaces of order ≥2 host the continuous binomial and beta processes

  14. The prevalence of coeliac disease is significantly higher in children compared with adults.

    Science.gov (United States)

    Mariné, M; Farre, C; Alsina, M; Vilar, P; Cortijo, M; Salas, A; Fernández-Bañares, F; Rosinach, M; Santaolalla, R; Loras, C; Marquès, T; Cusí, V; Hernández, M I; Carrasco, A; Ribes, J; Viver, J M; Esteve, M

    2011-02-01

    Some limited studies of coeliac disease have shown higher frequency of coeliac disease in infancy and adolescence than in adulthood. This finding has remained unnoticed and not adequately demonstrated. To assess whether there are age and gender differences in coeliac disease prevalence. A total of 4230 subjects were included consecutively (1 to ≥80 years old) reproducing the reference population by age and gender. Sample size was calculated assuming a population-based coeliac disease prevalence of 1:250. After an interim analysis, the paediatric sample was expanded (2010 children) due to high prevalence in this group. Anti-transglutaminase and antiendomysial antibodies were determined and duodenal biopsy was performed if positive. Log-linear models were fitted to coeliac disease prevalence by age allowing calculation of percentage change of prevalence. Differences between groups were compared using Chi-squared test. Twenty-one subjects had coeliac disease (male/female 1:2.5). Coeliac disease prevalence in the total population was 1:204. Coeliac disease prevalence was higher in children (1:71) than in adults (1:357) (P = 0.00005). A significant decrease of prevalence in older generations was observed [change of prevalence by age of -5% (95% CI: -7.58 to -2.42%)]. In the paediatric expanded group (1-14 years), a decrease of coeliac disease prevalence was also observed [prevalence change: -17% (95% CI: -25.02 to -6.10)]. The prevalence of coeliac disease in childhood was five times higher than in adults. Whether this difference is due to environmental factors influencing infancy, or latency of coeliac disease in adulthood, remains to be demonstrated in prospective longitudinal studies. © 2010 Blackwell Publishing Ltd.

  15. High Power Electronics - Key Technology for Wind Turbines

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Ma, Ke

    2014-01-01

    reliability challenges for the future wind turbines are explained. It is concluded that the wind turbine behavior/performance can be significantly improved by introducing power electronics, and there will be higher requirements for the power electronics performances in wind power application....

  16. Application of power spectrum, cepstrum, higher order spectrum and neural network analyses for induction motor fault diagnosis

    Science.gov (United States)

    Liang, B.; Iwnicki, S. D.; Zhao, Y.

    2013-08-01

    The power spectrum is defined as the square of the magnitude of the Fourier transform (FT) of a signal. The advantage of FT analysis is that it allows the decomposition of a signal into individual periodic frequency components and establishes the relative intensity of each component. It is the most commonly used signal processing technique today. If the same principle is applied for the detection of periodicity components in a Fourier spectrum, the process is called the cepstrum analysis. Cepstrum analysis is a very useful tool for detection families of harmonics with uniform spacing or the families of sidebands commonly found in gearbox, bearing and engine vibration fault spectra. Higher order spectra (HOS) (also known as polyspectra) consist of higher order moment of spectra which are able to detect non-linear interactions between frequency components. For HOS, the most commonly used is the bispectrum. The bispectrum is the third-order frequency domain measure, which contains information that standard power spectral analysis techniques cannot provide. It is well known that neural networks can represent complex non-linear relationships, and therefore they are extremely useful for fault identification and classification. This paper presents an application of power spectrum, cepstrum, bispectrum and neural network for fault pattern extraction of induction motors. The potential for using the power spectrum, cepstrum, bispectrum and neural network as a means for differentiating between healthy and faulty induction motor operation is examined. A series of experiments is done and the advantages and disadvantages between them are discussed. It has been found that a combination of power spectrum, cepstrum and bispectrum plus neural network analyses could be a very useful tool for condition monitoring and fault diagnosis of induction motors.

  17. External Stakeholders of Higher Education Institutions in Poland: Their Identification and Significance

    Science.gov (United States)

    Piotrowska-Piatek, Agnieszka

    2017-01-01

    In the context of the ongoing changes in the management systems of higher education, the issue of higher education institutions' (HEIs) relationships with external stakeholders are of key importance. This article discusses this problem from the perspective of Polish higher education system. The aim of it is to answer the following questions: (1)…

  18. High content of MYHC II in vastus lateralis is accompanied by higher VO2/power output ratio during moderate intensity cycling performed both at low and at high pedalling rates.

    Science.gov (United States)

    Majerczak, J; Szkutnik, Z; Karasinski, J; Duda, K; Kolodziejski, L; Zoladz, J A

    2006-06-01

    The aim of this study was to examine the relationship between the content of various types of myosin heavy chain isoforms (MyHC) in the vastus lateralis muscle and pulmonary oxygen uptake during moderate power output incremental exercise, performed at low and at high pedalling rates. Twenty one male subjects (mean +/- SD) aged 24.1 +/- 2.8 years; body mass 72.9 +/- 7.2 kg; height 179.1 +/- 4.8 cm; BMI 22.69 +/- 1.89 kg.m(-2); VO2max 50.6 +/- 5.3 ml.kg.min(-1), participated in this study. On separate days, they performed two incremental exercise tests at 60 rev.min(-1) and at 120 rev.min(-1), until exhaustion. Gas exchange variables were measured continuously breath by breath. Blood samples were taken for measurements of plasma lactate concentration prior to the exercise test and at the end of each step of the incremental exercise. Muscle biopsies were taken from the vastus lateralis muscle, using Bergström needle, and they were analysed for the content of MyHC I and MyHC II using SDS--PAGE and two groups (n=7, each) were selected: group H with the highest content of MyHC II (60.7 % +/- 10.5 %) and group L with the lowest content of MyHC II (27.6 % +/- 6.1 %). We have found that during incremental exercise at the power output between 30-120 W, performed at 60 rev.min(-1), oxygen uptake in the group H was significantly greater than in the group L (ANCOVA, p=0.003, upward shift of the intercept in VO2/power output relationship). During cycling at the same power output but at 120 rev.min(-1), the oxygen uptake was also higher in the group H, when compared to the group L (i.e. upward shift of the intercept in VO2/power output relationship, ANCOVA, p=0.002). Moreover, the increase in pedalling rate from 60 to 120 rev.min(-1) was accompanied by a significantly higher increase of oxygen cost of cycling and by a significantly higher plasma lactate concentration in subjects from group H. We concluded that the muscle mechanical efficiency, expressed by the VO2/PO ratio

  19. Measurements of higher-order mode damping in the PEP-II low-power test cavity

    International Nuclear Information System (INIS)

    Rimmer, R.A.; Goldberg, D.A.

    1993-05-01

    The paper describes the results of measurements of the Higher-Order Mode (HOM) spectrum of the low-power test model of the PEP-II RF cavity and the reduction in the Q's of the modes achieved by the addition of dedicated damping waveguides. All the longitudinal (monopole) and deflecting (dipole) modes below the beam pipe cut-off are identified by comparing their measured frequencies and field distributions with calculations using the URMEL code. Field configurations were determined using a perturbation method with an automated bead positioning system. The loaded Q's agree well with the calculated values reported previously, and the strongest HOMs are damped by more than three orders of magnitude. This is sufficient to reduce the coupled-bunch growth rates to within the capability of a reasonable feedback system. A high power test cavity will now be built to validate the thermal design at the 150 kW nominal operating level, as described elsewhere at this conference

  20. Global Discourses and Power/Knowledge: Theoretical Reflections on Futures of Higher Education during the Rise of Asia

    Science.gov (United States)

    Geerlings, L. R. C.; Lundberg, A.

    2018-01-01

    This paper re-reads a selection of critical interdisciplinary theories in an attempt to open a space in higher education for cross-cultural dialogue during the rise of Asia. Theories of globalization, deterritorialization, power/knowledge and postcolonialism indicate that students and academics have the ability to re-imagine and influence…

  1. The Relative Importance of Low Significance Level and High Power in Multiple Tests of Significance.

    Science.gov (United States)

    Westermann, Rainer; Hager, Willi

    1983-01-01

    Two psychological experiments--Anderson and Shanteau (1970), Berkowitz and LePage (1967)--are reanalyzed to present the problem of the relative importance of low Type 1 error probability and high power when answering a research question by testing several statistical hypotheses. (Author/PN)

  2. CEZ utility's coal-fired power plants: towards a higher environmental friendliness

    International Nuclear Information System (INIS)

    Kindl, V.; Spilkova, T.; Vanousek, I.; Stehlik, J.

    1996-01-01

    Environmental efforts of the major Czech utility, CEZ a.s., are aimed at reducing air pollution arising from electricity and heat generating facilities. There are 3 main kinds of activity in this respect: phasing out of coal fired power plants; technological provisions to reduce emissions of particulate matter, sulfur dioxide, and nitrogen oxides from those coal fired units that are to remain in operation after 1998; and completion of the Temelin nuclear power plant. In 1995, emissions of particulate matter, sulfur dioxide, nitrogen oxides, and carbon monoxide from CEZ's coal fired power plants were 19%, 79%, 59%, and 60%, respectively, with respect to the situation in 1992. The break-down of electricity generation by CEZ facilities (in GWh) was as follows in 1995: hydroelectric power plants 1673, nuclear power plants 12230, coal fired power plants without desulfurization equipment 30181, and coal fired power plants with desulfurization equipment 2277. Provisions implemented to improve the environmental friendliness of the individual CEZ's coal fired power plants are described in detail. (P.A.). 5 tabs., 1 fig

  3. Gamma power and cognition in patients with schizophrenia and their first-degree relatives.

    Science.gov (United States)

    Díez, Álvaro; Suazo, Vanessa; Casado, Pilar; Martín-Loeches, Manuel; Molina, Vicente

    2014-01-01

    Gamma oscillations are essential for functional neural assembly formation underlying higher cerebral functions. Previous studies concerning gamma band power in schizophrenia have yielded diverse results. In this study, we assessed gamma band power in minimally treated patients with schizophrenia, their first-degree relatives and healthy controls during an oddball paradigm performance, as well as the relation between gamma power and cognitive performance. We found a higher gamma power in the patient group than in the healthy controls at the P3, P4, Fz, Pz and T5 sites. Compared with their relatives, gamma power in the patients was only marginally higher over P3 and P4. We found a nearly significant inverse association between gamma power at F4 and Tower of London performance in the patients, as well as a significant inverse association between gamma power at T5 and verbal memory and working memory scores in the relatives. These results support higher total gamma power in association with schizophrenia and its inverse association with cognitive performance in patients and their first-degree relatives.

  4. Increase of EEG spectral theta power indicates higher risk of the development of severe cognitive decline in Parkinson’s disease after 3 years

    Directory of Open Access Journals (Sweden)

    Vitalii V Cozac

    2016-11-01

    Full Text Available Objective: We investigated quantitative electroencephalography (qEEG and clinical parameters as potential risk factors of severe cognitive decline in Parkinson’s disease.Methods: We prospectively investigated 37 patients with Parkinson’s disease at baseline and follow-up (after 3 years. Patients had no severe cognitive impairment at baseline. We used a summary score of cognitive tests as the outcome at follow-up. At baseline we assessed motor, cognitive, and psychiatric factors; qEEG variables (global relative median power spectra were obtained by a fully automated processing of high-resolution EEG (256-channels. We used linear regression models with calculation of the explained variance to evaluate the relation of baseline parameters with cognitive deterioration.Results: The following baseline parameters significantly predicted severe cognitive decline: global relative median power theta (4-8 Hz, cognitive task performance in executive functions and working memory.Conclusions: Combination of neurocognitive tests and qEEG improves identification of patients with higher risk of cognitive decline in PD.

  5. Thermoelectric power generator for variable thermal power source

    Science.gov (United States)

    Bell, Lon E; Crane, Douglas Todd

    2015-04-14

    Traditional power generation systems using thermoelectric power generators are designed to operate most efficiently for a single operating condition. The present invention provides a power generation system in which the characteristics of the thermoelectrics, the flow of the thermal power, and the operational characteristics of the power generator are monitored and controlled such that higher operation efficiencies and/or higher output powers can be maintained with variably thermal power input. Such a system is particularly beneficial in variable thermal power source systems, such as recovering power from the waste heat generated in the exhaust of combustion engines.

  6. Nuclear and thermal power plant power ramping capability

    International Nuclear Information System (INIS)

    Golovach, E.A.

    1983-01-01

    The possibilities of step power increase by NPP and TPP units under emergency conditions of power grids operation are considered. The data analysis has shown that power units ramping capability with WWER-440, WWER-1000 and RBMK-1000 reactors is higher than that of 300 MW power units on fossil fuel, at the initial time interval (0-30 s). These NPP power units satisfy as to ramping capability the energy system requirements. Higher NPP power units ramping capability is explained by the fact that relative pressure before turbine valves is decreased less than in straight-through boilers while the steam volumes time constant of steam separator-superheaters is less than that of intermediate superheatings. Higher power unit ramping capability with WWER-440 and RBMK-1000 reactors as compared with the WWER-1000 reactor is pointed out as well as the increase of WWER-1000 power unit capability using high-speed turbines

  7. Power in Households: Disentangling Bargaining Power

    OpenAIRE

    Mabsout, Ramzi; Staveren, Irene

    2009-01-01

    textabstractIntroduction Within the household bargaining literature, bargaining power is generally understood in terms of economic resources, such as income or assets. Empirical analyses of women’s bargaining power in households in developed and developing countries find that, in general, higher female incomes lead to higher bargaining power, which in turn tends to increase women’s relative wellbeing (Quisumbing, 2003). For assets, the empirical literature comes up with similar results, indic...

  8. Wind power generation and dispatch in competitive power markets

    Science.gov (United States)

    Abreu, Lisias

    Wind energy is currently the fastest growing type of renewable energy. The main motivation is led by more strict emission constraints and higher fuel prices. In addition, recent developments in wind turbine technology and financial incentives have made wind energy technically and economically viable almost anywhere. In restructured power systems, reliable and economical operation of power systems are the two main objectives for the ISO. The ability to control the output of wind turbines is limited and the capacity of a wind farm changes according to wind speeds. Since this type of generation has no production costs, all production is taken by the system. Although, insufficient operational planning of power systems considering wind generation could result in higher system operation costs and off-peak transmission congestions. In addition, a GENCO can participate in short-term power markets in restructured power systems. The goal of a GENCO is to sell energy in such a way that would maximize its profitability. However, due to market price fluctuations and wind forecasting errors, it is essential for the wind GENCO to keep its financial risk at an acceptable level when constituting market bidding strategies. This dissertation discusses assumptions, functions, and methodologies that optimize short-term operations of power systems considering wind energy, and that optimize bidding strategies for wind producers in short-term markets. This dissertation also discusses uncertainties associated with electricity market environment and wind power forecasting that can expose market participants to a significant risk level when managing the tradeoff between profitability and risk.

  9. Significantly higher Carabid beetle (Coleoptera: Carabidae) catch in conventionally than in organically managed Christmas tree plantations

    DEFF Research Database (Denmark)

    Bagge, Søren; Lund, Malthe; Rønn, Regin

    2012-01-01

    Carabid beetles play an important role as consumers of pest organisms in forestry and agriculture. Application of pesticides may negatively affect abundance and activity of carabid beetles, thus reducing their potential beneficial effect. We investigated how abundance and diversity of pitfall...... trapped carabid beetles (Coleoptera, Carabidae) varied between conventionally and organically managed Caucasian Fir (Abies nordmanniana (Stev.)) plantations, in northern Zealand, Denmark. We recorded significantly higher numbers of carabid beetle specimens and species at conventionally than at organically...

  10. A high-power versatile wireless power transfer for biomedical implants.

    Science.gov (United States)

    Jiang, Hao; Zhang, Jun Min; Liou, Shy Shenq; Fechter, Richard; Hirose, Shinjiro; Harrison, Michael; Roy, Shuvo

    2010-01-01

    Implantable biomedical actuators are highly desired in modern medicine. However, how to power up these biomedical implants remains a challenge since most of them need more than several hundreds mW of power. The air-core based radio-frequency transformer (two face-to-face inductive coils) has been the only non-toxic and non-invasive power source for implants for the last three decades [1]. For various technical constraints, the maximum delivered power is limited by this approach. The highest delivered power reported is 275 mW over 1 cm distance [2]. Also, the delivered power is highly vulnerable to the coils' geometrical arrangement and the electrical property of the medium around them. In this paper, a novel rotating-magnets based wireless power transfer that can deliver ∼10 W over 1 cm is demonstrated. The delivered power is significantly higher than the existing start-of-art. Further, the new method is versatile since there is no need to have the impedance matching networks that are highly susceptible to the operating frequency, the coil arrangement and the environment.

  11. Optical trapping of nanoparticles with significantly reduced laser powers by using counter-propagating beams (Presentation Recording)

    Science.gov (United States)

    Zhao, Chenglong; LeBrun, Thomas W.

    2015-08-01

    Gold nanoparticles (GNP) have wide applications ranging from nanoscale heating to cancer therapy and biological sensing. Optical trapping of GNPs as small as 18 nm has been successfully achieved with laser power as high as 855 mW, but such high powers can damage trapped particles (particularly biological systems) as well heat the fluid, thereby destabilizing the trap. In this article, we show that counter propagating beams (CPB) can successfully trap GNP with laser powers reduced by a factor of 50 compared to that with a single beam. The trapping position of a GNP inside a counter-propagating trap can be easily modulated by either changing the relative power or position of the two beams. Furthermore, we find that under our conditions while a single-beam most stably traps a single particle, the counter-propagating beam can more easily trap multiple particles. This (CPB) trap is compatible with the feedback control system we recently demonstrated to increase the trapping lifetimes of nanoparticles by more than an order of magnitude. Thus, we believe that the future development of advanced trapping techniques combining counter-propagating traps together with control systems should significantly extend the capabilities of optical manipulation of nanoparticles for prototyping and testing 3D nanodevices and bio-sensing.

  12. Bus Participation Factor Analysis for Harmonic Instability in Power Electronics Based Power Systems

    DEFF Research Database (Denmark)

    Ebrahimzadeh, Esmaeil; Blaabjerg, Frede; Wang, Xiongfei

    2018-01-01

    Compared with the conventional power systems, large-scale power electronics based power systems present a more complex situation, where harmonic instability may be induced by the mutual interactions between the inner control loops of the converters. This paper presents an approach to locate which...... power converters and buses are more sensitive and have significant contribution to the harmonic instability. In the approach, a power electronics based system is introduced as a Multi-Input Multi-Output (MIMO) dynamic system by means of a dynamic admittance matrix. Bus Participation Factors (PFs......) are calculated by the oscillatory mode sensitivity analysis versus the elements of the MIMO transfer function matrix. The PF analysis detects which power electronic converters or buses have a higher participation in harmonic instability excitation than others or at which buses such instability problems have...

  13. Challenges in higher order mode Raman amplifiers

    DEFF Research Database (Denmark)

    Rottwitt, Karsten; Nielsen, Kristian; Friis, Søren Michael Mørk

    2015-01-01

    A higher order Raman amplifier model that take random mode coupling into account ispresented. Mode dependent gain and signal power fluctuations at the output of the higher order modeRaman amplifier are discussed......A higher order Raman amplifier model that take random mode coupling into account ispresented. Mode dependent gain and signal power fluctuations at the output of the higher order modeRaman amplifier are discussed...

  14. Performance evaluation recommendations of nuclear power plants outdoor significant civil structures earthquake resistance. Technical documentation

    International Nuclear Information System (INIS)

    2005-06-01

    The Japan Society of Civil Engineers has updated performance evaluation recommendations of nuclear power plants outdoor significant civil structures earthquake resistance in June 2005. Experimental and analytical considerations on the seismic effects evaluation criteria, such as analytical seismic models of soils for underground structures, effects of vertical motions on time-history dynamic analysis and shear fracture of reinforced concretes by cyclic loadings, were shown in this document and incorporated in new recommendations. (T. Tanaka)

  15. Performance evaluation recommendations and manuals of nuclear power plants outdoor significant civil structures earthquake resistance

    International Nuclear Information System (INIS)

    2005-06-01

    Performance evaluation recommendations and manuals of nuclear power plants outdoor significant civil structures earthquake resistance have been updated in June 2005 by the Japan Society of Civil Engineers. Based on experimental and analytical considerations on the recommendations of May 2002, analytical seismic models of soils for underground structures, effects of vertical motions on time-history dynamic analysis and shear fracture of reinforced concretes by cyclic loadings have been evaluated and incorporated in new recommendations. (T. Tanaka)

  16. An approach toward estimating the safety significance of normal and abnormal operating procedures in nuclear power plants

    International Nuclear Information System (INIS)

    Grant, T.F.; Harris, M.S.

    1989-01-01

    The Nuclear Regulatory Commission's TMI Action Plan calls for a long-term plan to upgrade operating procedures in nuclear power plants. The scope of Generic Issue Human Factors 4.4, which stems from this requirement, includes the recommendation of improvements in nuclear power plant normal and abnormal operating procedures (NOPs and AOPs) and the implementation of appropriate regulatory action. This paper will describe the objectives, methodologies, and results of a Battelle-conducted value impact assessment to determine the costs and benefits of having the NRC implement regulatory action that would specify requirements for the preparation of acceptable NOPs and AOPs by the Commission's nuclear power plant licensees. The results of this value impact assessment are expressed in terms of ten cost/benefit attributes that can be affected by the NRC regulatory action. Five of these attributes require the calculation of change in public risk that could be expected to result from the action which, in this case, required determining the safety significance of NOPs and AOPs. In order to estimate this safety significance, a multi-step methodology was created that relies on an existing Probabilistic Risk Assessment (PRA) to provide a quantitative framework for modeling the role of operating procedures. The purpose of this methodology is to determine what impact the improvement of NOPs and AOPs would have on public health and safety

  17. Background does not significantly affect power-exponential fitting of gastric emptying curves

    International Nuclear Information System (INIS)

    Jonderko, K.

    1987-01-01

    Using a procedure enabling the assessment of background radiation, research was done to elucidate the course of changes in background activity during gastric emptying measurements. Attention was focused on the changes in the shape of power-exponential fitted gastric emptying curves after correction for background was performed. The observed pattern of background counts allowed to explain the shifts of the parameters characterizing power-exponential curves connected with background correction. It was concluded that background had a negligible effect on the power-exponential fitting of gastric emptying curves. (author)

  18. Music: Its Expressive Power and Moral Significance

    Directory of Open Access Journals (Sweden)

    Sarah Whitfield

    2010-05-01

    Full Text Available The creation and practice of music is tightly wound with human emotion, character, and experience. Music arouses sentiment and cannot be underestimated as a powerful shaper of human virtue, character, and emotion. As vehicles of musical expression, musicians possess the ability to profoundly influence an audience for good or for evil. Thus, the nature of music and the manner in which musicians utilize it creates innumerable ramifications that cannot be ignored. The pervasiveness of this notion is largely attributed to the Greek theorists, who ascribed various emotions and moral implications to particular modes. The prominent Greek philosophers Plato and Aristotle affirmed that music contained an intrinsic element that was conducive to the promotion of moral or spiritual harmony and order in the soul. Plato and his contemporaries attributed specific character-forming qualities to each of the individual harmonia, or musical modes, believing that each could shape human character in a distinct way. These ideas inevitably persisted and continue to endure. Theorists throughout history have agreed that music profoundly influences human character and shapes morality.

  19. Low-power laser therapy for carpal tunnel syndrome: effective optical power

    Directory of Open Access Journals (Sweden)

    Yan Chen

    2016-01-01

    Full Text Available Low-power laser therapy has been used for the non-surgical treatment of mild to moderate carpal tunnel syndrome, although its efficacy has been a long-standing controversy. The laser parameters in low-power laser therapy are closely related to the laser effect on human tissue. To evaluate the efficacy of low-power laser therapy, laser parameters should be accurately measured and controlled, which has been ignored in previous clinical trials. Here, we report the measurement of the effective optical power of low-power laser therapy for carpal tunnel syndrome. By monitoring the backside reflection and scattering laser power from human skin at the wrist, the effective laser power can be inferred. Using clinical measurements from 30 cases, we found that the effective laser power differed significantly among cases, with the measured laser reflection coefficient ranging from 1.8% to 54%. The reflection coefficient for 36.7% of these 30 cases was in the range of 10–20%, but for 16.7% of cases, it was higher than 40%. Consequently, monitoring the effective optical power during laser irradiation is necessary for the laser therapy of carpal tunnel syndrome.

  20. Active Power Control of Waked Wind Farms: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); van Wingerden, Jan-Willem [Delft University of Technology; Pao, Lucy [University of Colorado; Aho, Jacob [University of Colorado

    2017-08-15

    Active power control can be used to balance the total power generated by wind farms with the power consumed on the electricity grid. With the increasing penetration levels of wind energy, there is an increasing need for this ancillary service. In this paper, we show that the tracking of a certain power reference signal provided by the transmission system operator can be significantly improved by using feedback control at the wind farm level. We propose a simple feedback control law that significantly improves the tracking behavior of the total power output of the farm, resulting in higher performance scores. The effectiveness of the proposed feedback controller is demonstrated using high-fidelity computational fluid dynamics simulations of a small wind farm.

  1. Effect of higher frequency on the classification of steady-state visual evoked potentials

    Science.gov (United States)

    Won, Dong-Ok; Hwang, Han-Jeong; Dähne, Sven; Müller, Klaus-Robert; Lee, Seong-Whan

    2016-02-01

    Objective. Most existing brain-computer interface (BCI) designs based on steady-state visual evoked potentials (SSVEPs) primarily use low frequency visual stimuli (e.g., visual fatigue and no stimulus-related seizures. The fundamental objective of this study was to investigate the effect of stimulation frequency and duty-cycle on the usability of an SSVEP-based BCI system. Approach. We developed an SSVEP-based BCI speller using multiple LEDs flickering with low frequencies (6-14.9 Hz) with a duty-cycle of 50%, or higher frequencies (26-34.7 Hz) with duty-cycles of 50%, 60%, and 70%. The four different experimental conditions were tested with 26 subjects in order to investigate the impact of stimulation frequency and duty-cycle on performance and visual fatigue, and evaluated with a questionnaire survey. Resting state alpha powers were utilized to interpret our results from the neurophysiological point of view. Main results. The stimulation method employing higher frequencies not only showed less visual fatigue, but it also showed higher and more stable classification performance compared to that employing relatively lower frequencies. Different duty-cycles in the higher frequency stimulation conditions did not significantly affect visual fatigue, but a duty-cycle of 50% was a better choice with respect to performance. The performance of the higher frequency stimulation method was also less susceptible to resting state alpha powers, while that of the lower frequency stimulation method was negatively correlated with alpha powers. Significance. These results suggest that the use of higher frequency visual stimuli is more beneficial for performance improvement and stability as time passes when developing practical SSVEP-based BCI applications.

  2. Anodic biofilms in microbial fuel cells harbor low numbers of higher-power-producing bacteria than abundant genera

    KAUST Repository

    Kiely, Patrick D.

    2010-07-15

    Microbial fuel cell (MFC) anode communities often reveal just a few genera, but it is not known to what extent less abundant bacteria could be important for improving performance. We examined the microbial community in an MFC fed with formic acid for more than 1 year and determined using 16S rRNA gene cloning and fluorescent in situ hybridization that members of the Paracoccus genus comprised most (~30%) of the anode community. A Paracoccus isolate obtained from this biofilm (Paracoccus denitrificans strain PS-1) produced only 5.6 mW/m 2, whereas the original mixed culture produced up to 10 mW/m 2. Despite the absence of any Shewanella species in the clone library, we isolated a strain of Shewanella putrefaciens (strain PS-2) from the same biofilm capable of producing a higher-power density (17.4 mW/m2) than the mixed culture, although voltage generation was variable. Our results suggest that the numerical abundance of microorganisms in biofilms cannot be assumed a priori to correlate to capacities of these predominant species for high-power production. Detailed screening of bacterial biofilms may therefore be needed to identify important strains capable of high-power generation for specific substrates. © 2010 Springer-Verlag.

  3. Anodic biofilms in microbial fuel cells harbor low numbers of higher-power-producing bacteria than abundant genera

    Energy Technology Data Exchange (ETDEWEB)

    Kiely, Patrick D.; Call, Douglas F.; Yates, Matthew D.; Regan, John M.; Logan, Bruce E. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Civil and Environmental Engineering

    2010-09-15

    Microbial fuel cell (MFC) anode communities often reveal just a few genera, but it is not known to what extent less abundant bacteria could be important for improving performance. We examined the microbial community in an MFC fed with formic acid for more than 1 year and determined using 16S rRNA gene cloning and fluorescent in situ hybridization that members of the Paracoccus genus comprised most ({proportional_to}30%) of the anode community. A Paracoccus isolate obtained from this biofilm (Paracoccus denitrificans strain PS-1) produced only 5.6 mW/m{sup 2}, whereas the original mixed culture produced up to 10 mW/m{sup 2}. Despite the absence of any Shewanella species in the clone library, we isolated a strain of Shewanella putrefaciens (strain PS-2) from the same biofilm capable of producing a higher-power density (17.4 mW/m{sup 2}) than the mixed culture, although voltage generation was variable. Our results suggest that the numerical abundance of microorganisms in biofilms cannot be assumed a priori to correlate to capacities of these predominant species for high-power production. Detailed screening of bacterial biofilms may therefore be needed to identify important strains capable of high-power generation for specific substrates. (orig.)

  4. Anodic biofilms in microbial fuel cells harbor low numbers of higher-power-producing bacteria than abundant genera

    KAUST Repository

    Kiely, Patrick D.; Call, Douglas F.; Yates, Matthew D.; Regan, John M.; Logan, Bruce E.

    2010-01-01

    Microbial fuel cell (MFC) anode communities often reveal just a few genera, but it is not known to what extent less abundant bacteria could be important for improving performance. We examined the microbial community in an MFC fed with formic acid for more than 1 year and determined using 16S rRNA gene cloning and fluorescent in situ hybridization that members of the Paracoccus genus comprised most (~30%) of the anode community. A Paracoccus isolate obtained from this biofilm (Paracoccus denitrificans strain PS-1) produced only 5.6 mW/m 2, whereas the original mixed culture produced up to 10 mW/m 2. Despite the absence of any Shewanella species in the clone library, we isolated a strain of Shewanella putrefaciens (strain PS-2) from the same biofilm capable of producing a higher-power density (17.4 mW/m2) than the mixed culture, although voltage generation was variable. Our results suggest that the numerical abundance of microorganisms in biofilms cannot be assumed a priori to correlate to capacities of these predominant species for high-power production. Detailed screening of bacterial biofilms may therefore be needed to identify important strains capable of high-power generation for specific substrates. © 2010 Springer-Verlag.

  5. Higher capacity, lower carbon dioxide emissions. Idle power compensation in HV lines; Mehr Kapazitaet, weniger Kohlendioxid. Blindleistungskompensation bei Hochspannungsleitungen

    Energy Technology Data Exchange (ETDEWEB)

    Auer, Jan-Hendrik von [Alstom Grid GmbH, Berlin (Germany). Team Leistungselektronik und Kompensationsanlagen

    2012-07-01

    Even today, many HP lines have reached their limits. It is therefore highly urgent to find measures for optimum utilization of the available overhead transmssion capacities, e.g. by idle power compensation. Together with a filter for harmonics reduction, this will ensure higher grid stability and enhance transport capacities while reducing transport losses, thus saving money and reducing CO{sub 2} emissions. (orig./AKB)

  6. Performance evaluation recommendations of nuclear power plants outdoor significant civil structures earthquake resistance. Performance evaluation examples

    International Nuclear Information System (INIS)

    2005-06-01

    The Japan Society of Civil Engineers has updated performance evaluation recommendations of nuclear power plants outdoor significant civil structures earthquake resistance in June 2005. Based on experimental and analytical considerations, analytical seismic models of soils for underground structures, effects of vertical motions on time-history dynamic analysis and shear fracture of reinforced concretes by cyclic loadings have been incorporated in new recommendations. This document shows outdoor civil structures earthquake resistance and endurance performance evaluation examples based on revised recommendations. (T. Tanaka)

  7. Fukushima- the aftermath. The japanese power consumption has significantly decreased to adapt to a fading nuclear activity. Enerdata- Energy Efficiency and Demand

    International Nuclear Information System (INIS)

    2012-01-01

    In this study, a series of analyses supported by graphs assess the power supply evolution in Japan since Fukushima, which has decreased by 11% of reactors in operation since December 2011. Measures implemented in summer 2011 to adapt demand to a lower supply and their significant impact on the power consumption are also analyzed. (authors)

  8. Significance of oceanographic field investigations for siting coastal thermal and nuclear power plants

    Digital Repository Service at National Institute of Oceanography (India)

    Krishnakumar, V.; Swamy, G.N.; Sastry, J

    stream_size 7 stream_content_type text/plain stream_name Irrig_Power_J_49_129.pdf.txt stream_source_info Irrig_Power_J_49_129.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

  9. Emissions characteristics of higher alcohol/gasoline blends

    International Nuclear Information System (INIS)

    Gautam, M.; Martin, D.W.; Carder, D.

    2000-01-01

    An experimental investigation was conducted to determine the emissions characteristics of higher alcohols and gasoline (UTG96) blends. While lower alcohols (methanol and ethanol) have been used in blends with gasoline, very little work has been done or reported on higher alcohols (propanol, butanol and pentanol). Comparisons of emissions and fuel characteristics between higher alcohol/gasoline blends and neat gasoline were made to determine the advantages and disadvantages of blending higher alcohols with gasoline. All tests were conducted on a single-cylinder Waukesha Cooperative Fuel Research engine operating at steady state conditions and stoichiometric air-fuel (A/F) ratio. Emissions test were conducted at the optimum spark timing-knock limiting compression ratio combination for the particular blend being tested. The cycle emission [mass per unit time (g/h)] of CO, CO 2 and organic matter hydrocarbon equivalent (OMHCE) from the higher alcohol/gasoline blends were very similar to those from neat gasoline. Cycle emissions of NO x from the blends were higher than those from neat gasoline. However, for all the emissions species considered, the brake specific emissions (g/kW h) were significantly lower for the higher alcohol/gasoline blends than for neat gasoline. This was because the blends had greater resistance to knock and allowed higher compression ratios, which increased engine power output. The contribution of alcohols and aldehydes to the overall OMHCE emissions was found to be minimal. Cycle fuel consumption (g/h) of higher alcohol/gasoline blends was slightly higher than with neat gasoline due to the lower stoichiometric A/F ratios required by the blends. However, the brake specific fuel consumption (g/kW h) for the blends was significantly lower than that for neat gasoline. (Author)

  10. On probabilistic forecasting of wind power time-series

    DEFF Research Database (Denmark)

    Pinson, Pierre

    power dynamics. In both cases, the model parameters are adaptively and recursively estimated, time-adaptativity being the result of exponential forgetting of past observations. The probabilistic forecasting methodology is applied at the Horns Rev wind farm in Denmark, for 10-minute ahead probabilistic...... forecasting of wind power generation. Probabilistic forecasts generated from the proposed methodology clearly have higher skill than those obtained from a classical Gaussian assumption about wind power predictive densities. Corresponding point forecasts also exhibit significantly lower error criteria....

  11. Power in Households: Disentangling Bargaining Power

    NARCIS (Netherlands)

    R. Mabsout (Ramzi); I.P. van Staveren (Irene)

    2009-01-01

    textabstractIntroduction Within the household bargaining literature, bargaining power is generally understood in terms of economic resources, such as income or assets. Empirical analyses of women’s bargaining power in households in developed and developing countries find that, in general, higher

  12. Heat pipe cooling of power processing magnetics

    Science.gov (United States)

    Hansen, I. G.; Chester, M.

    1979-01-01

    The constant demand for increased power and reduced mass has raised the internal temperature of conventionally cooled power magnetics toward the upper limit of acceptability. The conflicting demands of electrical isolation, mechanical integrity, and thermal conductivity preclude significant further advancements using conventional approaches. However, the size and mass of multikilowatt power processing systems may be further reduced by the incorporation of heat pipe cooling directly into the power magnetics. Additionally, by maintaining lower more constant temperatures, the life and reliability of the magnetic devices will be improved. A heat pipe cooled transformer and input filter have been developed for the 2.4 kW beam supply of a 30-cm ion thruster system. This development yielded a mass reduction of 40% (1.76 kg) and lower mean winding temperature (20 C lower). While these improvements are significant, preliminary designs predict even greater benefits to be realized at higher power. This paper presents the design details along with the results of thermal vacuum operation and the component performance in a 3 kW breadboard power processor.

  13. Planning for Higher Education.

    Science.gov (United States)

    Lindstrom, Caj-Gunnar

    1984-01-01

    Decision processes for strategic planning for higher education institutions are outlined using these parameters: institutional goals and power structure, organizational climate, leadership attitudes, specific problem type, and problem-solving conditions and alternatives. (MSE)

  14. Fish impingement at estuarine power stations and its significance to commercial fishing

    International Nuclear Information System (INIS)

    Turnpenny, A.W.H.

    1989-01-01

    The abstraction of cooling water (CW) at power stations sited on tidal waters inevitably leads to mortalities of some fish which are drawn in with the CW supply and become impinged on the intake screens. These fish are predominantly 0- or 1-group juveniles which, owing to their small size, are unable to resist intake currents. Commercial fishermen often object to the fact that juvenile fish are killed in this way. Their concern stems from the fact that in order to protect stocks, commercial fishing is restricted to fish which are above a statutory minimum landing size, whereas the majority of fish killed by impingement are below this size. This Report considers the significance of impingement mortalities at four estuarine sites in Britain for six commercially important species. Life tables are used to establish expected survival trajectories for each species and to compute reproductive potential. Each fish killed on intake screens is then considered in terms of the fraction of the reproductive potential of a single adult at maturity, and is ascribed an 'adult equivalent' value. Total catches of mixed juveniles and adults are then presented as 'adult equivalent' values. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Wind power and the conditions at a liberalized power market

    International Nuclear Information System (INIS)

    Morthorst, P.E.

    2003-01-01

    Wind power is undergoing a rapid development nationally as well as globally and in a number of countries covers an increasing part of the power supply. At the same time an ongoing liberalization of power markets is taking place and to an increasing extent the owners of wind power plants will themselves have to be responsible for trading the power at the spot market and financially handling the balancing. In the western part of Denmark (Jutland/Funen area), wind-generated power from time to time covers almost 100% of total power consumption. Therefore some examples are chosen from this area to analyse in more detail how well large amounts of wind power in the short-term are handled at the power spot market. It turns out that there is a tendency that more wind power in the system in the short run leads to relatively lower spot prices, while less wind power implies relatively higher spot prices, although, with the exception of December 2002, in general no strong relationship is found. A stronger relationship is found at the regulating market, where there is a fairly clear tendency that the more wind power produced, the higher is the need for down-regulation, and, correspondingly, the less wind power produced, the higher is the need for up-regulation. In general for the Jutland/Funen area the average cost of down-regulation is calculated as 1 2 c euros/kWh regulated for 2002, while the cost of up-regulation amounts to 0 7 c euros/kWh regulated. (author)

  17. The need for power, need for influence, sense of power, and directiveness in female and male superiors and subordinates

    Directory of Open Access Journals (Sweden)

    Dagna Kocur

    2017-12-01

    Full Text Available Background The purpose of the study was to examine the phenomenon of power within an organisation from the vantage point of gender, the occupied position, earnings, and the number of subordinates. Participants and procedure The sample group comprised 107 female and 98 male participants. The mean age was 42.14 years (SD = 11.73. The study covered 100 superiors and 105 subordinates. The research tools were: the Need for Power and Influence Questionnaire (Bennett, 1988, the Personal Sense of Power Scale (Anderson, John, & Keltner, 2012, and the Directiveness Scale SD (Ray, 1976. Results The superiors scored significantly higher on the need for power, need for influence, and directiveness. They also scored higher in terms of the need for power in relations with other people, with colleagues, and in superior-subordinate relations. The number of male leaders was conspicuously greater than the number of female leaders. Furthermore, women had fewer subordinates than men and earned less than men. Female participants scored lower on the sense of power and the need for power scales. Conclusions Occupying either an executive or subordinate position differentiates between women and men in terms of sense of power in interpersonal relationships. The findings on sense of power in the professional context may be applied in organisational psychology in order to increase employees’ competence and qualifications.

  18. Exercise dependence and the drive for muscularity in male bodybuilders, power lifters, and fitness lifters.

    Science.gov (United States)

    Hale, Bruce D; Roth, Andrew D; DeLong, Ryan E; Briggs, Michael S

    2010-06-01

    Researchers have hypothesized differences in exercise dependence and drive for muscularity between bodybuilders and power lifters, while others have not found the predicted differences. This study assessed 146 weight lifters (bodybuilders, n=59; power lifters, n=47; fitness lifters, n=40) on the Exercise Dependence Scale, Bodybuilding Dependence Scale, and the Drive for Muscularity Scale. Results showed that bodybuilders and power lifters were significantly higher than fitness lifters on EDS Total, 7 EDS scales, and the 3 BDS scales. In contrast, power lifters were found to be significantly higher on DMS Total and DMS Behavior scales than bodybuilders. The regression results suggest that exercise dependence may be directly related to the drive for muscularity. 2010 Elsevier Ltd. All rights reserved.

  19. Comparing costs of power and heat production by prospective and present sources

    International Nuclear Information System (INIS)

    Novak, S.

    1979-01-01

    Capital and running costs are compared of power and heat production from different sources. The lowest capital costs were found for coal-fired power plants followed by light water reactor power plants. The capital costs of other types of power plants, such as wind, geothermal, solar, thermonuclear power plants are significantly higher. The estimated specific cost for electric power production in 1985 for a nuclear power plant is lower than for a fossil-fuel power plant. It is estimated that in 1985 coal will be the cheapest heat source. (Ha)

  20. High power density carbonate fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Yuh, C.; Johnsen, R.; Doyon, J.; Allen, J. [Energy Research Corp., Danbury, CT (United States)

    1996-12-31

    Carbonate fuel cell is a highly efficient and environmentally clean source of power generation. Many organizations worldwide are actively pursuing the development of the technology. Field demonstration of multi-MW size power plant has been initiated in 1996, a step toward commercialization before the turn of the century, Energy Research Corporation (ERC) is planning to introduce a 2.85MW commercial fuel cell power plant with an efficiency of 58%, which is quite attractive for distributed power generation. However, to further expand competitive edge over alternative systems and to achieve wider market penetration, ERC is exploring advanced carbonate fuel cells having significantly higher power densities. A more compact power plant would also stimulate interest in new markets such as ships and submarines where space limitations exist. The activities focused on reducing cell polarization and internal resistance as well as on advanced thin cell components.

  1. Normal LVEF measurements are significantly higher in females asassessed by post-stress resting Tc-99m sestamibi gated myocardial perfusion SPECT

    International Nuclear Information System (INIS)

    Kim, Jong Ho; Shin, Eak Kyun

    1999-01-01

    Volume-LVEF relationship is one of the most important factors of automatic EF quantification algorithm from gated myocardial perfusion SPECT(gMPS) (Germano et al. JNM, 1995). Gender difference whereby normal LVEF measurements are higher in females assessed by gMPS (Yao et al. JNM 1997). To validate true physiologic value of LVEF vs sampling or measured error, various parameters were evaluated statistically in both gender and age matched 200 subjects (mean age= 58.41±15.01) with normal LVEF more than 50%, and a low likelihood of coronary artery disease. Correlation between LVEDVi(ml/m2) and LVEF was highly significant (r=-0.62, p<0.0001) with similar correlations noted in both male (r=-0.45, p<0.0001) and female (r=-0.67, p<0.0001) subgroups. By multivariate analysis, LV volume and stroke volume was the most significant factor influencing LVEF in male and female, respectively. In conclusion, there is a significant negative correlation between LV volume and LVEF as measured by Tc-99m gated SPECT. Higher normal LVEF value should be applied to females as assessed by post-stress resting Tc-99m Sestamibi gated myocardial perfusion SPECT

  2. Ageing of significant to safety structure elements of nuclear power plants

    International Nuclear Information System (INIS)

    Maksimovas, G.; Ramanauskiene, A.; Ziliukas, A.

    1999-01-01

    The paper analyzes the ageing problems of structure elements in nuclear power plants. The standard documents and principal parts of the ageing evaluation program are presented. The ageing evaluation model is being worked out and degradation mechanisms of different atomic reactor materials are being compared. (author)

  3. Propagation of high power electromagnetic beam in relativistic magnetoplasma: Higher order paraxial ray theory

    Science.gov (United States)

    Gill, Tarsem Singh; Kaur, Ravinder; Mahajan, Ranju

    2010-09-01

    This paper presents an analysis of self-consistent, steady-state, theoretical model, which explains the ring formation in a Gaussian electromagnetic beam propagating in a magnetoplasma, characterized by relativistic nonlinearity. Higher order terms (up to r4) in the expansion of the dielectric function and the eikonal have been taken into account. The condition for the formation of a dark and bright ring derived earlier by Misra and Mishra [J. Plasma Phys. 75, 769 (2009)] has been used to study focusing/defocusing of the beam. It is seen that inclusion of higher order terms does significantly affect the dependence of the beam width on the distance of propagation. Further, the effect of the magnetic field and the nature of nonlinearity on the ring formation and self-focusing of the beam have been explored.

  4. Propagation of high power electromagnetic beam in relativistic magnetoplasma: Higher order paraxial ray theory

    International Nuclear Information System (INIS)

    Gill, Tarsem Singh; Kaur, Ravinder; Mahajan, Ranju

    2010-01-01

    This paper presents an analysis of self-consistent, steady-state, theoretical model, which explains the ring formation in a Gaussian electromagnetic beam propagating in a magnetoplasma, characterized by relativistic nonlinearity. Higher order terms (up to r 4 ) in the expansion of the dielectric function and the eikonal have been taken into account. The condition for the formation of a dark and bright ring derived earlier by Misra and Mishra [J. Plasma Phys. 75, 769 (2009)] has been used to study focusing/defocusing of the beam. It is seen that inclusion of higher order terms does significantly affect the dependence of the beam width on the distance of propagation. Further, the effect of the magnetic field and the nature of nonlinearity on the ring formation and self-focusing of the beam have been explored.

  5. Predictive Power of Primary and Secondary School Success Criterion on Transition to Higher Education Examination Scores

    OpenAIRE

    Atilla ÖZDEMİR; Selahattin GELBAL

    2016-01-01

    It is seen that education has a significant effect that changes an individual’s life in our country in which education is a way of moving up the social ladder. In order to continue to a higher education program after graduating from high school, students have to succeed in transition to higher education examination. Thus, the entrance exam is an important factor to determine the future of the students. In our country, middle school grades and high school grade point average that is added to u...

  6. The Integrity of ACSR Full Tension Single-Stage Splice Connector at Higher Operation Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [ORNL; Lara-Curzio, Edgar [ORNL; King Jr, Thomas J [ORNL

    2008-10-01

    Due to increases in power demand and limited investment in new infrastructure, existing overhead power transmission lines often need to operate at temperatures higher than those used for the original design criteria. This has led to the accelerated aging and degradation of splice connectors. It is manifested by the formation of hot-spots that have been revealed by infrared imaging during inspection. The implications of connector aging is two-fold: (1) significant increases in resistivity of the splice connector (i.e., less efficient transmission of electricity) and (2) significant reductions in the connector clamping strength, which could ultimately result in separation of the power transmission line at the joint. Therefore, the splice connector appears to be the weakest link in electric power transmission lines. This report presents a protocol for integrating analytical and experimental approaches to evaluate the integrity of full tension single-stage splice connector assemblies and the associated effective lifetime at high operating temperature.

  7. Cost estimates for nuclear power in the UK

    International Nuclear Information System (INIS)

    Harris, Grant; Heptonstall, Phil; Gross, Robert; Handley, David

    2013-01-01

    Current UK Government support for nuclear power has in part been informed by cost estimates that suggest that electricity from new nuclear power stations will be competitive with alternative low carbon generation options. The evidence and analysis presented in this paper suggests that the capital cost estimates for nuclear power that are being used to inform these projections rely on costs escalating over the pre-construction and construction phase of the new build programme at a level significantly below those that have been experienced by past US and European programmes. This paper applies observed construction time and cost escalation rates to the published estimates of capital costs for new nuclear plant in the UK and calculates the potential impact on levelised cost per unit of electricity produced. The results suggest that levelised cost may turn out to be significantly higher than expected which in turn has important implications for policy, both in general terms of the potential costs to consumers and more specifically for negotiations around the level of policy support and contractual arrangements offered to individual projects through the proposed contract for difference strike price. -- Highlights: •Nuclear power projects costs can rise substantially during the construction period. •Pre-construction and construction time can be much longer than anticipated. •Adjusting estimates for observed experience increases levelised costs significantly. •Higher costs suggest that more policy support than envisaged may be required

  8. Integration of renewable energies into the German power system and their influence on investments in new power plants. Integrated consideration of effects on power plant investment and operation

    Energy Technology Data Exchange (ETDEWEB)

    Harthan, Ralph Oliver

    2015-01-14

    The increasing share of renewable energies in the power sector influences the economic viability of investments in new conventional power plants. Many studies have investigated these issues by considering power plant operation or the long-term development of the power plant fleet. However, power plant decommissioning, investment and operation are intrinsically linked. This doctoral thesis therefore presents a modelling framework for an integrated consideration of power plant decommissioning, investment and operation. In a case study focusing on Germany, the effects of the integration of renewable energies on power plant decommissioning, investment and operation are evaluated in the context of different assumptions regarding the remaining lifetime of nuclear power plants. With regard to the use of nuclear power, a phase-out scenario and a scenario with lifetime extension of nuclear power plants (by on average 12 years) are considered. The results show that static decommissioning (i.e. considering fixed technical lifetimes) underestimates the capacity available in the power sector in the scenario without lifetime extension since retrofit measures (versus decommissioning) are not taken into account. In contrast, capacity available in the case of nuclear lifetime extension is overestimated since mothballing (versus regular operation) is not considered. If the impact on decommissioning decisions of profit margins accrued during power plant operation are considered (''dynamic decommissioning''), the electricity price reduction effect due to a lifetime extension is reduced by more than half in comparison to static decommissioning. Scarcity situations do not differ significantly between the scenarios with and without lifetime extension with dynamic decommissioning; in contrast, there is a significantly higher need for imports without lifetime extension with static decommissioning. The case study demonstrates that further system flexibility is needed for

  9. Integration of renewable energies into the German power system and their influence on investments in new power plants. Integrated consideration of effects on power plant investment and operation

    International Nuclear Information System (INIS)

    Harthan, Ralph Oliver

    2015-01-01

    The increasing share of renewable energies in the power sector influences the economic viability of investments in new conventional power plants. Many studies have investigated these issues by considering power plant operation or the long-term development of the power plant fleet. However, power plant decommissioning, investment and operation are intrinsically linked. This doctoral thesis therefore presents a modelling framework for an integrated consideration of power plant decommissioning, investment and operation. In a case study focusing on Germany, the effects of the integration of renewable energies on power plant decommissioning, investment and operation are evaluated in the context of different assumptions regarding the remaining lifetime of nuclear power plants. With regard to the use of nuclear power, a phase-out scenario and a scenario with lifetime extension of nuclear power plants (by on average 12 years) are considered. The results show that static decommissioning (i.e. considering fixed technical lifetimes) underestimates the capacity available in the power sector in the scenario without lifetime extension since retrofit measures (versus decommissioning) are not taken into account. In contrast, capacity available in the case of nuclear lifetime extension is overestimated since mothballing (versus regular operation) is not considered. If the impact on decommissioning decisions of profit margins accrued during power plant operation are considered (''dynamic decommissioning''), the electricity price reduction effect due to a lifetime extension is reduced by more than half in comparison to static decommissioning. Scarcity situations do not differ significantly between the scenarios with and without lifetime extension with dynamic decommissioning; in contrast, there is a significantly higher need for imports without lifetime extension with static decommissioning. The case study demonstrates that further system flexibility is needed for

  10. Understanding cross-national trends in high-tech renewable power equipment exports to the United States

    International Nuclear Information System (INIS)

    Sawhney, Aparna; Kahn, Matthew E.

    2012-01-01

    We track US imports of advanced technology wind and solar power-generation equipment from a panel of countries during 1989–2010, and examine the determining factors including country size, sector-specific US FDI outflow, and domestic wind and solar power generation. Differentiating between the core high-tech and the balance of system equipment, we find US imports of both categories have grown at significantly higher rate from the relatively poorer countries, and particularly China and India. Larger countries are found to be exporting significantly more, and US FDI is found to play a significant positive role in the exports of high-tech equipment for the poor countries. For the core wind and solar high-tech equipment, we find domestic renewable power generation of the exporting countries also played a significant positive role. - Highlights: ► We track US imports of advanced technology wind and solar power-generation equipment. ► US imports of both categories have grown at significantly higher rate from China and India. ► US FDI is found to play a significant positive role in the exports of high-tech equipment.

  11. Effects of saddle height on economy and anaerobic power in well-trained cyclists.

    Science.gov (United States)

    Peveler, Willard W; Green, James M

    2011-03-01

    In cycling, saddle height adjustment is critical for optimal performance and injury prevention. A 25-35° knee angle is recommended for injury prevention, whereas 109% of inseam, measured from floor to ischium, is recommended for optimal performance. Previous research has demonstrated that these 2 methods produce significantly different saddle heights and may influence cycling performance. This study compared performance between these 2 methods for determining saddle height. Subjects consisted of 11 well-trained (VO2max = 61.55 ± 4.72 ml·kg·min) male cyclists. Subjects completed a total of 8 performance trials consisting of a graded maximal protocol, three 15-minute economy trials, and 4 anaerobic power trials. Dependent measures for economy (VO2, heart rate, and rating of perceived exertion) and anaerobic power (peak power and mean power) were compared using repeated measures analysis of variance (α = 0.05). VO2 was significantly lower (reflecting greater economy) at a 25° knee angle (44.77 ± 6.40 ml·kg·min) in comparison to a 35° knee angle (45.22 ± 6.79 ml·kg·min) and 109% of inseam (45.98 ± 5.33 ml·kg·min). Peak power at a 25° knee angle (1,041.55 ± 168.72 W) was significantly higher in relation to 109% of inseam (1,002.05 ± 147.65 W). Mean power at a 25° knee angle (672.37 ± 90.21 W) was significantly higher in relation to a 35° knee angle (654.71 ± 80.67 W). Mean power was significantly higher at 109% of inseam (662.86 ± 79.72 W) in relation to a 35° knee angle (654.71 ± 80.67 W). Use of 109% of inseam fell outside the recommended 25-35° range 73% of the time. Use of 25° knee angle appears to provide optimal performance while keeping knee angle within the recommended range for injury prevention.

  12. Motivation and social contexts: a crossnational pilot study of achievement, power, and affiliation motives.

    Science.gov (United States)

    Xu, Xiaoyan; Xu, Yangang; Mellor, David; Duan, Liqiong

    2012-01-01

    Previous research suggests that there is a relationship between social contexts (e.g., economic growth, engagement in wars) and motives within populations. In particular, high achievement motive is associated with subsequent economic growth, which in turn increases power motive. Increased national achievement and power motives have been argued to precede social changes that lead to decreased affiliation motives, and engagement in wars. The present study aimed to examine differences in achievement, power, and affiliation motives between 266 college students in China (a nation with sustained high economic growth) and 255 college students in the USA (a nation with previously strong but now slowing economic growth, and engaged in war). Analysis of personal strivings suggested that Chinese college students showed significantly higher levels of achievement motive than the American college students, but American college students showed significantly higher levels of affiliation motive than Chinese college students. Overall, males exhibited higher achievement motivation than females. No significant interaction effects were found for gender by location for any of the three motives. The findings are discussed in relation to previous research.

  13. Luminosity Optimization for a Higher-Energy LHC

    CERN Document Server

    Dominguez, O

    2011-01-01

    A Higher-Energy Large Hadron Collider (HE-LHC) is an option to further push the energy frontier of particle physics beyond the present LHC. A beam energy of 16.5 TeV would require 20 T dipole magnets in the existing LHC tunnel, which should be compared with 7 TeV and 8.33 T for the nominal LHC. Since the synchrotron radiation power increases with the fourth power of the energy, radiation damping becomes significant for the HE-LHC. It calls for transverse and longitudinal emittance control vis-a-vis beam-beam interaction and Landau damping. The heat load from synchrotron radiation, gas scattering, and electron cloud also increases with respect to the LHC. In this paper we discuss the proposed HE-LHC beam parameters; the time evolution of luminosity, beam-beam tune shifts, and emittances during an HE-LHC store; the expected heat load; and luminosity optimization schemes for both round and flat beams.

  14. ASSESSING SELF-STUDY WORK’S SIGNIFICANT SKILLS FOR SUCCESSFUL LEARNING IN THE HIGHER SCHOOL

    Directory of Open Access Journals (Sweden)

    Galina V. Milovanova

    2017-06-01

    Full Text Available Introduction: the problem of organizing students’ independent work/self-study is not new, but the changes in the higher school for the last two decades show that the experience accumulated in the traditional educational model can be applied only when it is processed in the present-day conditions. The article analyses the innovative component of the educational process in terms of a significant increase in the volume of compulsory independent work in the university. Particular attention is paid to determining the levels of the formation of skills for independent work in terms of students’ readiness for its implementa¬tion. The aim of the research is to identify the most significant skills of independent work for successful study at the university. Materials and Methods: the research is based on general scholarly methods: analysis, comparison, generalisation. A questionnaire survey was carried out and a correlation analysis of the results was presented. The mathematical statistics methods in Excel application were u sed for processing the survey data. Results: the article focused on the relevance of formation the students’ ability to work independently in the learning process. Requirements for professionals recognize the need for knowledge and skills, but more importantly, the ability and readiness to complete this knowledge and be in a state of continuous education and self-education. In turn, readiness to self-education cannot exist without independent work. The ratio of students to work independently and their skills’ levels in this area of the gnostic, design, structural, organisational and communicative blocks were identified because o f the research. Discussion and Conclusions: the levels of the formation of the skills for independent work influence on the success of the learning. There is a correlation between indicators of achievement and the ability to work independently. Organisation and communication skills have significant

  15. Calibration of higher eigenmodes of cantilevers

    International Nuclear Information System (INIS)

    Labuda, Aleksander; Kocun, Marta; Walsh, Tim; Meinhold, Jieh; Proksch, Tania; Meinhold, Waiman; Anderson, Caleb; Proksch, Roger; Lysy, Martin

    2016-01-01

    A method is presented for calibrating the higher eigenmodes (resonant modes) of atomic force microscopy cantilevers that can be performed prior to any tip-sample interaction. The method leverages recent efforts in accurately calibrating the first eigenmode by providing the higher-mode stiffness as a ratio to the first mode stiffness. A one-time calibration routine must be performed for every cantilever type to determine a power-law relationship between stiffness and frequency, which is then stored for future use on similar cantilevers. Then, future calibrations only require a measurement of the ratio of resonant frequencies and the stiffness of the first mode. This method is verified through stiffness measurements using three independent approaches: interferometric measurement, AC approach-curve calibration, and finite element analysis simulation. Power-law values for calibrating higher-mode stiffnesses are reported for several cantilever models. Once the higher-mode stiffnesses are known, the amplitude of each mode can also be calibrated from the thermal spectrum by application of the equipartition theorem.

  16. Calibration of higher eigenmodes of cantilevers

    Energy Technology Data Exchange (ETDEWEB)

    Labuda, Aleksander; Kocun, Marta; Walsh, Tim; Meinhold, Jieh; Proksch, Tania; Meinhold, Waiman; Anderson, Caleb; Proksch, Roger [Asylum Research, an Oxford Instruments Company, Santa Barbara, California 93117 (United States); Lysy, Martin [Department of Statistics and Actuarial Science, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2016-07-15

    A method is presented for calibrating the higher eigenmodes (resonant modes) of atomic force microscopy cantilevers that can be performed prior to any tip-sample interaction. The method leverages recent efforts in accurately calibrating the first eigenmode by providing the higher-mode stiffness as a ratio to the first mode stiffness. A one-time calibration routine must be performed for every cantilever type to determine a power-law relationship between stiffness and frequency, which is then stored for future use on similar cantilevers. Then, future calibrations only require a measurement of the ratio of resonant frequencies and the stiffness of the first mode. This method is verified through stiffness measurements using three independent approaches: interferometric measurement, AC approach-curve calibration, and finite element analysis simulation. Power-law values for calibrating higher-mode stiffnesses are reported for several cantilever models. Once the higher-mode stiffnesses are known, the amplitude of each mode can also be calibrated from the thermal spectrum by application of the equipartition theorem.

  17. The Neuromuscular Qualities of Higher- and Lower-Level Mixed-Martial-Arts Competitors.

    Science.gov (United States)

    James, Lachlan P; Beckman, Emma M; Kelly, Vincent G; Haff, G Gregory

    2017-05-01

    To determine whether the maximal strength, impulse, and power characteristics of competitive mixed-martial-arts (MMA) athletes differ according to competition level. Twenty-nine male semiprofessional and amateur MMA competitors were stratified into either higher-level (HL) or lower-level (LL) performers on the basis of competition grade and success. The 1-repetition-maximum (1RM) squat was used to assess lower-body dynamic strength, and a spectrum of impulse, power, force, and velocity variables were evaluated during an incremental-load jump squat. In addition, participants performed an isometric midthigh pull (IMTP) and 1RM bench press to determine whole-body isometric force and upper-body dynamic strength capabilities, respectively. All force and power variables were expressed relative to body mass (BM). The HL competitors produced significantly superior values across a multitude of measures. These included 1RM squat strength (1.84 ± 0.23 vs 1.56 ± 0.24 kg BM; P = .003), in addition to performance in the incremental-load jump squat that revealed greater peak power (P = .005-.002), force (P = .002-.004), and velocity (P = .002-.03) at each load. Higher measures of impulse (P = .01-.04) were noted in a number of conditions. Average power (P = .002-.02) and velocity (P = .01-.04) at all loads in addition to a series of rate-dependent measures were also superior in the HL group (P = .005-.02). The HL competitors' 1RM bench-press values approached significantly greater levels (P = .056) than the LL group's, but IMTP performance did not differ between groups. Maximal lower-body neuromuscular capabilities are key attributes distinguishing HL from LL MMA competitors. This information can be used to inform evidenced-based training and performance-monitoring practices.

  18. Space-to-Space Power Beaming Enabling High Performance Rapid Geocentric Orbit Transfer

    Science.gov (United States)

    Dankanich, John W.; Vassallo, Corinne; Tadge, Megan

    2015-01-01

    The use of electric propulsion is more prevalent than ever, with industry pursuing all electric orbit transfers. Electric propulsion provides high mass utilization through efficient propellant transfer. However, the transfer times become detrimental as the delta V transitions from near-impulsive to low-thrust. Increasing power and therefore thrust has diminishing returns as the increasing mass of the power system limits the potential acceleration of the spacecraft. By using space-to-space power beaming, the power system can be decoupled from the spacecraft and allow significantly higher spacecraft alpha (W/kg) and therefore enable significantly higher accelerations while maintaining high performance. This project assesses the efficacy of space-to-space power beaming to enable rapid orbit transfer while maintaining high mass utilization. Concept assessment requires integrated techniques for low-thrust orbit transfer steering laws, efficient large-scale rectenna systems, and satellite constellation configuration optimization. This project includes the development of an integrated tool with implementation of IPOPT, Q-Law, and power-beaming models. The results highlight the viability of the concept, limits and paths to infusion, and comparison to state-of-the-art capabilities. The results indicate the viability of power beaming for what may be the only approach for achieving the desired transit times with high specific impulse.

  19. 78 FR 27470 - Culturally Significant Objects Imported for Exhibition Determinations: “Shaping Power: Luba...

    Science.gov (United States)

    2013-05-10

    ... Determinations: ``Shaping Power: Luba Masterworks From the Royal Museum for Central Africa'' SUMMARY: Notice is... objects to be included in the exhibition ``Shaping Power: Luba Masterworks from the Royal Museum for Central Africa,'' imported from abroad for temporary exhibition within the United States, are of cultural...

  20. Developing Student Worksheet Based On Higher Order Thinking Skills on the Topic of Transistor Power Amplifier

    Science.gov (United States)

    Sardia Ratna Kusuma, Luckey; Rakhmawati, Lusia; Wiryanto

    2018-04-01

    The purpose of this study is to develop a student worksheet about the transistor power amplifier based on higher order thinking skills include critical, logical, reflective, metacognitive, and creative thinking, which could be useful for teachers in improving student learning outcomes. Research and Development (R & D) methodology was used in this study. The pilot study of the worksheet was carried out with class X AV 2 at SMK Negeri 5 Surabaya. The result showed satisfies aspect of validity with 81.76 %, and effectiveness (students learning outcomes is classically passed out with percentage of 82.4 % and the students gave positive responses to the student worksheet of each statement. It can be concluded that this worksheet categorized good and worthy to be used as a source of learning in the learning activities.

  1. Polymer-Polymer Förster Resonance Energy Transfer Significantly Boosts the Power Conversion Efficiency of Bulk-Heterojunction Solar Cells.

    Science.gov (United States)

    Gupta, Vinay; Bharti, Vishal; Kumar, Mahesh; Chand, Suresh; Heeger, Alan J

    2015-08-01

    Optically resonant donor polymers can exploit a wider range of the solar spectrum effectively without a complicated tandem design in an organic solar cell. Ultrafast Förster resonance energy transfer (FRET) in a polymer-polymer system that significantly improves the power conversion efficiency in bulk heterojunction polymer solar cells from 6.8% to 8.9% is demonstrated, thus paving the way to achieving 15% efficient solar cells. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Higher order mode damping of a higher harmonic superconducting cavity for SSRF

    International Nuclear Information System (INIS)

    Yu Haibo; Liu Jianfei; Hou Hongtao; Ma Zhenyu; Feng Xiqiang; Mao Dongqing

    2012-01-01

    Adopting a higher harmonic cavity on a synchrotron radiation facility can increase the beam lifetime and suppress the beam instability. In this paper, we report the simulation and preliminary design on higher order modes (HOMs) damping of the designed and fabricated higher harmonic superconducting cavity for Shanghai Synchrotron Radiation Facility (SSRF). The requirements for the HOM damping are analyzed, and the length and location of the HOM damper are optimized by using the SEAFISH code. The results show that the design can provide heavy damping for harmful HOMs with decreased impedance, and the beam instability requirement of SSRF can be satisfied. By using the ABCI code, the loss factor is obtained and the HOM power is estimated. (authors)

  3. Development of a low-cost biogas filtration system to achieve higher-power efficient AC generator

    Science.gov (United States)

    Mojica, Edison E.; Ardaniel, Ar-Ar S.; Leguid, Jeanlou G.; Loyola, Andrea T.

    2018-02-01

    The paper focuses on the development of a low-cost biogas filtration system for alternating current generator to achieve higher efficiency in terms of power production. A raw biogas energy comprises of 57% combustible element and 43% non-combustible elements containing carbon dioxide (36%), water vapor (5%), hydrogen sulfide (0.5%), nitrogen (1%), oxygen (0 - 2%), and ammonia (0 - 1%). The filtration system composes of six stages: stage 1 is the water scrubber filter intended to remove the carbon dioxide and traces of hydrogen sulfide; stage 2 is the silica gel filter intended to reduce the water vapor; stage 3 is the iron sponge filter intended to remove the remaining hydrogen sulfide; stage 4 is the sodium hydroxide solution filter intended to remove the elemental sulfur formed during the interaction of the hydrogen sulfide and the iron sponge and for further removal of carbon dioxide; stage 5 is the silica gel filter intended to further eliminate the water vapor gained in stage 4; and, stage 6 is the activated carbon filter intended to remove the carbon dioxide. The filtration system was able to lower the non-combustible elements by 72% and thus, increasing the combustible element by 54.38%. The unfiltered biogas is capable of generating 16.3 kW while the filtered biogas is capable of generating 18.6 kW. The increased in methane concentration resulted to 14.11% increase in the power output. The outcome resulted to better engine performance in the generation of electricity.

  4. Power uprates in nuclear power plants: international experiences and approaches for implementation

    International Nuclear Information System (INIS)

    Kang, Ki Sig

    2008-01-01

    The greater demand for electricity and the available capacity within safety margins in some operating NPPs are prompting nuclear utilities to request license modification to enable operation at a higher power level, beyond their original license provisions. Such plant modifications require an in-depth safety analysis to evaluate the possible safety impact. The analysis must consider the thermo hydraulic, radiological and structural aspects, and the plant behavior, while taking into account the capability of the structures, systems and components, and the reactor protection and safeguard systems set points. The purpose of this paper is to introduce international experiences and approaches for implementation of power uprates related to the reactor thermal power of nuclear power plants. The paper is intended to give the reader a general overview of the major processes, work products, issues, challenges, events, and experiences in the power uprates program. The process of increasing the licensed power level of a nuclear power plants is called a power uprate. One way of increasing the thermal output from a reactor is to increase the amount of fissile material in use. It is also possible to increase the core power by increasing the performance of the high power bundles. Safety margins can be maintained by either using fuels with a higher performance, or through the use of improved methods of analysis to demonstrate that the required margins are retained even at the higher power levels. The paper will review all types of power uprates, from small to large, and across various reactor types, including light and heavy water, pressurized, and boiling water reactors. Generally, however, the content of the report focuses on power uprates of the stretch and extended type. The International Atomic Energy Agency (IAEA) is developing a technical guideline on power uprates and side effects of power uprates in nuclear power plants

  5. Metric-affine formalism of higher derivative scalar fields in cosmology

    International Nuclear Information System (INIS)

    Li, Mingzhe; Wang, Xiulian

    2012-01-01

    Higher derivative scalar field theories have received considerable attention for the potentially explanations of the initial state of the universe or the current cosmic acceleration which they might offer. They have also attracted many interests in the phenomenological studies of infrared modifications of gravity. These theories are mostly studied by the metric variational approach in which only the metric is the fundamental field to account for the gravitation. In this paper we study the higher derivative scalar fields with the metric-affine formalism where the affine connection is treated arbitrarily at the beginning. Because the higher derivative scalar fields couple to the connection directly in a covariant theory these two formalisms will lead to different results. These differences are suppressed by the powers of the Planck mass and are usually expected to have small effects. But in some cases they may cause non-negligible deviations. We show by a higher derivative dark energy model that the two formalisms lead to significantly different pictures of the future universe

  6. Solar thermal aided power generation

    International Nuclear Information System (INIS)

    Hu, Eric; Yang, YongPing; Nishimura, Akira; Yilmaz, Ferdi; Kouzani, Abbas

    2010-01-01

    Fossil fuel based power generation is and will still be the back bone of our world economy, albeit such form of power generation significantly contributes to global CO 2 emissions. Solar energy is a clean, environmental friendly energy source for power generation, however solar photovoltaic electricity generation is not practical for large commercial scales due to its cost and high-tech nature. Solar thermal is another way to use solar energy to generate power. Many attempts to establish solar (solo) thermal power stations have been practiced all over the world. Although there are some advantages in solo solar thermal power systems, the efficiencies and costs of these systems are not so attractive. Alternately by modifying, if possible, the existing coal-fired power stations to generate green sustainable power, a much more efficient means of power generation can be reached. This paper presents the concept of solar aided power generation in conventional coal-fired power stations, i.e., integrating solar (thermal) energy into conventional fossil fuelled power generation cycles (termed as solar aided thermal power). The solar aided power generation (SAPG) concept has technically been derived to use the strong points of the two technologies (traditional regenerative Rankine cycle with relatively higher efficiency and solar heating at relatively low temperature range). The SAPG does not only contribute to increase the efficiencies of the conventional power station and reduce its emission of the greenhouse gases, but also provides a better way to use solar heat to generate the power. This paper presents the advantages of the SAPG at conceptual level.

  7. Topography and Higher Order Corneal Aberrations of the Fellow Eye in Unilateral Keratoconus.

    Science.gov (United States)

    Aksoy, Sibel; Akkaya, Sezen; Özkurt, Yelda; Kurna, Sevda; Açıkalın, Banu; Şengör, Tomris

    2017-10-01

    Comparison of topography and corneal higher order aberrations (HOA) data of fellow normal eyes of unilateral keratoconus patients with keratoconus eyes and control group. The records of 196 patients with keratoconus were reviewed. Twenty patients were identified as unilateral keratoconus. The best corrected visual acuity (BCVA), topography and aberration data of the unilateral keratoconus patients' normal eyes were compared with their contralateral keratoconus eyes and with control group eyes. For statistical analysis, flat and steep keratometry values, average corneal power, cylindrical power, surface regularity index (SRI), surface asymmetry index (SAI), inferior-superior ratio (I-S), keratoconus prediction index, and elevation-depression power (EDP) and diameter (EDD) topography indices were selected. Mean age of the unilateral keratoconus patients was 26.05±4.73 years and that of the control group was 23.6±8.53 years (p>0.05). There was no statistical difference in BCVA between normal and control eyes (p=0.108), whereas BCVA values were significantly lower in eyes with keratoconus (p=0.001). Comparison of quantitative topographic indices between the groups showed that all indices except the I-S ratio were significantly higher in the normal group than in the control group (p<0.05). The most obvious differences were in the SRI, SAI, EDP, and EDD values. All topographic indices were higher in the keratoconus eyes compared to the normal fellow eyes. There was no difference between normal eyes and the control group in terms of spherical aberration, while coma, trefoil, irregular astigmatism, and total HOA values were higher in the normal eyes of unilateral keratoconus patients (p<0.05). All HOA values were higher in keratoconus eyes than in the control group. According to our study, SRI, SAI, EDP, EDD values, and HOA other than spherical aberration were higher in the clinically and topographically normal fellow eyes of unilateral keratoconus patients when compared

  8. Variability in large-scale wind power generation: Variability in large-scale wind power generation

    Energy Technology Data Exchange (ETDEWEB)

    Kiviluoma, Juha [VTT Technical Research Centre of Finland, Espoo Finland; Holttinen, Hannele [VTT Technical Research Centre of Finland, Espoo Finland; Weir, David [Energy Department, Norwegian Water Resources and Energy Directorate, Oslo Norway; Scharff, Richard [KTH Royal Institute of Technology, Electric Power Systems, Stockholm Sweden; Söder, Lennart [Royal Institute of Technology, Electric Power Systems, Stockholm Sweden; Menemenlis, Nickie [Institut de recherche Hydro-Québec, Montreal Canada; Cutululis, Nicolaos A. [DTU, Wind Energy, Roskilde Denmark; Danti Lopez, Irene [Electricity Research Centre, University College Dublin, Dublin Ireland; Lannoye, Eamonn [Electric Power Research Institute, Palo Alto California USA; Estanqueiro, Ana [LNEG, Laboratorio Nacional de Energia e Geologia, UESEO, Lisbon Spain; Gomez-Lazaro, Emilio [Renewable Energy Research Institute and DIEEAC/EDII-AB, Castilla-La Mancha University, Albacete Spain; Zhang, Qin [State Grid Corporation of China, Beijing China; Bai, Jianhua [State Grid Energy Research Institute Beijing, Beijing China; Wan, Yih-Huei [National Renewable Energy Laboratory, Transmission and Grid Integration Group, Golden Colorado USA; Milligan, Michael [National Renewable Energy Laboratory, Transmission and Grid Integration Group, Golden Colorado USA

    2015-10-25

    The paper demonstrates the characteristics of wind power variability and net load variability in multiple power systems based on real data from multiple years. Demonstrated characteristics include probability distribution for different ramp durations, seasonal and diurnal variability and low net load events. The comparison shows regions with low variability (Sweden, Spain and Germany), medium variability (Portugal, Ireland, Finland and Denmark) and regions with higher variability (Quebec, Bonneville Power Administration and Electric Reliability Council of Texas in North America; Gansu, Jilin and Liaoning in China; and Norway and offshore wind power in Denmark). For regions with low variability, the maximum 1 h wind ramps are below 10% of nominal capacity, and for regions with high variability, they may be close to 30%. Wind power variability is mainly explained by the extent of geographical spread, but also higher capacity factor causes higher variability. It was also shown how wind power ramps are autocorrelated and dependent on the operating output level. When wind power was concentrated in smaller area, there were outliers with high changes in wind output, which were not present in large areas with well-dispersed wind power.

  9. Water Exchange Produces Significantly Higher Adenoma Detection Rate Than Water Immersion: Pooled Data From 2 Multisite Randomized Controlled Trials.

    Science.gov (United States)

    Leung, Felix W; Koo, Malcolm; Cadoni, Sergio; Falt, Premysl; Hsieh, Yu-Hsi; Amato, Arnaldo; Erriu, Matteo; Fojtik, Petr; Gallittu, Paolo; Hu, Chi-Tan; Leung, Joseph W; Liggi, Mauro; Paggi, Silvia; Radaelli, Franco; Rondonotti, Emanuele; Smajstrla, Vit; Tseng, Chih-Wei; Urban, Ondrej

    2018-03-02

    To test the hypothesis that water exchange (WE) significantly increases adenoma detection rates (ADR) compared with water immersion (WI). Low ADR was linked to increased risk for interval colorectal cancers and related deaths. Two recent randomized controlled trials of head-to-head comparison of WE, WI, and traditional air insufflation (AI) each showed that WE achieved significantly higher ADR than AI, but not WI. The data were pooled from these 2 studies to test the above hypothesis. Two trials (5 sites, 14 colonoscopists) that randomized 1875 patients 1:1:1 to AI, WI, or WE were pooled and analyzed with ADR as the primary outcome. The ADR of AI (39.5%) and WI (42.4%) were comparable, significantly lower than that of WE (49.6%) (vs. AI P=0.001; vs. WI P=0.033). WE insertion time was 3 minutes longer than that of AI (Prate (vs. AI) of the >10 mm advanced adenomas. Right colon combined advanced and sessile serrated ADR of AI (3.4%) and WI (5%) were comparable and were significantly lower than that of WE (8.5%) (vs. AI P<0.001; vs. WI P=0.039). Compared with AI and WI, the superior ADR of WE offsets the drawback of a significantly longer insertion time. For quality improvement focused on increasing adenoma detection, WE is preferred over WI. The hypothesis that WE could lower the risk of interval colorectal cancers and related deaths should be tested.

  10. Comprehensive Power Losses Model for Electronic Power Transformer

    DEFF Research Database (Denmark)

    Yue, Quanyou; Li, Canbing; Cao, Yijia

    2018-01-01

    and considering the impact of the non-unity power factor and the three-phase unbalanced current, the overall power losses in the distribution network when using the EPT to replace the conventional transformer is analyzed, and the conditions in which the application of the EPT can cause less power losses...... reduced power losses in the distribution network require a comprehensive consideration when comparing the power losses of theEPT and conventional transformer. In this paper, a comprehensive power losses analysis model for the EPT in distribution networks is proposed. By analyzing the EPT self-losses......The electronic power transformer (EPT) has highe rpower losses than the conventional transformer. However, the EPT can correct the power factor, compensate the unbalanced current and reduce the line power losses in the distribution network.Therefore, the higher losses of the EPT and the consequent...

  11. Comprehensive Power Losses Model for Electronic Power Transformer

    DEFF Research Database (Denmark)

    Yue, Quanyou; Li, Canbing; Cao, Yijia

    2018-01-01

    The electronic power transformer (EPT) has highe rpower losses than the conventional transformer. However, the EPT can correct the power factor, compensate the unbalanced current and reduce the line power losses in the distribution network.Therefore, the higher losses of the EPT and the consequent...... reduced power losses in the distribution network require a comprehensive consideration when comparing the power losses of theEPT and conventional transformer. In this paper, a comprehensive power losses analysis model for the EPT in distribution networks is proposed. By analyzing the EPT self......-losses and considering the impact of the non-unity power factor and the three-phase unbalanced current, the overall power losses in the distribution network when using the EPT to replace the conventional transformer is analyzed, and the conditions in which the application of the EPT can cause less power losses...

  12. Concrete component aging and its significance relative to life extension of nuclear power plants

    International Nuclear Information System (INIS)

    Naus, D.J.

    1986-09-01

    The objectives of this study are to (1) expand upon the work that was initiated in the first two Electric Power Research Institute studies relative to longevity and life extension considerations of safety-related concrete components in light-water reactor (LWR) facilities and (2) provide background that will logically lead to subsequent development of a methodology for assessing and predicting the effects of aging on the performance of concrete-based materials and components. These objectives are consistent with Nuclear Plant Aging Research (NPAR) Program goals: (1) to identify and characterize aging and service wear effects that, if unchecked, could cause degradation of structures, components, and systems and, thereby, impair plant safety; (2) to identify methods of inspection, surveillance, and monitoring or of evaluating residual life of structures, components, and systems that will ensure timely detection of significant aging effects before loss of safety function; and (3) to evaluate the effectiveness of storage, maintenance, repair, and replacement practices in mitigating the rate and extent of degradation caused by aging and service wear

  13. The market value of nuclear power

    International Nuclear Information System (INIS)

    Gupta, N.K.; Thompson, H.G. Jr.

    1999-01-01

    What are the factors and circumstances that have made some plants more valuable to others than to their original owners? What is currently keeping nuclear plants, with their relatively low operating cost and environmental impacts, at the bottom of the heap? Why will some nuclear plants have significantly higher market values in the future while others will fail? What circumstances are likely to change in the near future that could significantly alter this market? In this article, the authors address these questions and attempt to provide insights into the unique market for nuclear power. The authors will proceed by first introducing the components of generation asset valuation, then discussing recent experiences with the sales of non-nuclear and nuclear power plants. Next, the authors will provide some explanation for why non-nuclear assets are enjoying a robust market while the market for nuclear plants remains immature. Finally, the authors present an analysis of the future value of nuclear power and a view of one road to take to get there

  14. The market value of nuclear power

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, N.K.; Thompson, H.G. Jr.

    1999-10-01

    What are the factors and circumstances that have made some plants more valuable to others than to their original owners? What is currently keeping nuclear plants, with their relatively low operating cost and environmental impacts, at the bottom of the heap? Why will some nuclear plants have significantly higher market values in the future while others will fail? What circumstances are likely to change in the near future that could significantly alter this market? In this article, the authors address these questions and attempt to provide insights into the unique market for nuclear power. The authors will proceed by first introducing the components of generation asset valuation, then discussing recent experiences with the sales of non-nuclear and nuclear power plants. Next, the authors will provide some explanation for why non-nuclear assets are enjoying a robust market while the market for nuclear plants remains immature. Finally, the authors present an analysis of the future value of nuclear power and a view of one road to take to get there.

  15. Thermoelectric self-cooling for power electronics: Increasing the cooling power

    International Nuclear Information System (INIS)

    Martinez, Alvaro; Astrain, David; Aranguren, Patricia

    2016-01-01

    Thermoelectric self-cooling was firstly conceived to increase, without electricity consumption, the cooling power of passive cooling systems. This paper studies the combination of heat pipe exchangers and thermoelectric self-cooling, and demonstrates its applicability to the cooling of power electronics. Experimental tests indicate that source-to-ambient thermal resistance reduces by around 30% when thermoelectric self-cooling system is installed, compared to that of the heat pipe exchanger under natural convection. Neither additional electric power nor cooling fluids are required. This thermal resistance reaches 0.346 K/W for a heat flux of 24.1 kW/m"2, being one order of magnitude lower than that obtained in previous designs. In addition, the system adapts to the cooling demand, reducing this thermal resistance for increasing heat. Simulation tests have indicated that simple system modifications allow relevant improvements in the cooling power. Replacement of a thermoelectric module with a thermal bridge leads to 33.54 kW/m"2 of top cooling power. Likewise, thermoelectric modules with shorter legs and higher number of pairs lead to a top cooling power of 44.17 kW/m"2. These results demonstrate the applicability of thermoelectric self-cooling to power electronics. - Highlights: • Cooling power of passive systems increased. • No electric power consumption. • Applicable for the cooling of power electronics. • Up to 44.17 kW/m"2 of cooling power, one order of magnitude higher. • Source-to-ambient thermal resistance reduces by 30%.

  16. Power in Practice: Adult Education and the Struggle for Knowledge and Power in Society. The Jossey-Bass Higher and Adult Education Series.

    Science.gov (United States)

    Cervero, Ronald M.; Wilson, Arthur L.

    This book contains 14 papers on adult education and the struggle for knowledge and power in society. The following papers are included: "At the Heart of Practice: The Struggle for Knowledge and Power" (Ronald M. Cervero, Arthur L. Wilson); "The Power of Economic Globalization: Deskilling Immigrant Women through Training"…

  17. A Low-input-voltage Wireless Power Transfer for Biomedical Implants

    DEFF Research Database (Denmark)

    Jiang, Hao; Bai, Kangjun; Zhu, Weijie

    2015-01-01

    Wireless power transfer is an essential technology to increase implants' longevity. A pair of inductivelycoupled coils operating at radio-frequency is extensively used to deliver electrical power to implants wirelessly. In this system, a power conditioning circuit is required convert the induced...... in the rectifier for the efficient AC to DC conversion. This requirement results in larger coil size, shorter operating distance or more stringent geometrical alignment between the two coils. In this paper, a low-input-voltage wireless power transfer has been demonstrated. In this system, the opencircuit voltage...... time-varying AC power harvested by the receiving coil to a stable DC power that is needed for powering circuits and sensors. Most existing power conditioning circuits require the induced voltage of the receiving coil to be significantly higher than the turn-on voltage of the diodes used...

  18. Empathy, Sense of Power, and Personality: Do They Change During Pediatric Residency?

    Science.gov (United States)

    Greenberg, Larrie; Agrawal, Dewesh; Toto, Regina; Blatt, Benjamin

    2015-08-01

    Empathy is a critical competency in medicine. Prior studies demonstrate a longitudinal decrease in empathy during residency; however, they have not included pediatric residents. The relations among the expression of empathy, sense of power (ability to influence other's behavior), and personality traits in residents also have not been addressed. Lastly, there are no data on how residents compare with the general nonmedical population in their expression of empathy. The purposes of our study were to assess whether empathy, sense of power, and personality type were statistically correlated; if resident empathy declines over time; and how resident empathy compares with that of nonmedical peers. In 2010, a cohort of individuals entering pediatric residency were given three validated survey instruments at the beginning of their first and third years of training to explore longitudinal changes in empathy, sense of power, and major personality traits. We found no decrease in resident empathy in 2 years of pediatric training, no changes in their sense of power, and no statistically significant correlation between empathetic tendencies and sense of power. When compared with the general nonmedical population, pediatric residents rated themselves higher in empathy. As expected, the two components of empathy (empathic concern and perspective taking) were moderately correlated. Of the major personality traits, only agreeableness showed significant correlation with empathy. Pediatric resident empathy did not decrease longitudinally, unlike studies in other residents. There was no inverse relation between self-perceptions of sense of power and empathy as is present in the business literature. Finally, pediatric resident empathy was significantly higher when compared with a general nonmedical population.

  19. Childhood Trauma Associated with Enhanced High Frequency Band Powers and Induced Subjective Inattention of Adults

    Directory of Open Access Journals (Sweden)

    Seung-Hwan Lee

    2017-08-01

    Full Text Available Childhood trauma can lead to various psychological and cognitive symptoms. It has been demonstrated that high frequency electroencephalogram (EEG powers could be closely correlated with inattention. In this study, we explored the relationship between high frequency EEG powers, inattention, symptoms of adult attention deficit hyperactivity disorder (ADHD, and childhood traumatic experiences. A total of 157 healthy Korean adult volunteers were included and divided into two groups using the Childhood Trauma Questionnaire (CTQ score. The subjective inattention scores, ADHD scale, and anxiety and depression symptom were evaluated. EEG was recorded and quantitative band powers were analyzed. The results were as follows: (1 the high CTQ group showed significantly increased delta, beta1, beta2, beta3 and gamma, and significantly decreased low alpha power compared to the low CTQ group; (2 the high CTQ group had higher inattention score compared to the low CTQ group; (3 the high CTQ group had higher adult ADHD scores; (4 CTQ scores showed significant positive correlations with inattention scores, and adult ADHD scores; (5 unexpectedly, the inattention scores showed significant positive correlations with beta powers and a negative correlation with low alpha power; and (6 the moderated mediation model was confirmed: the depression fully mediated the path from state anxiety to inattention, and the CTQ significantly moderated the pathway between anxiety and depression. Our results show the possibility that childhood adversity may cause subjective inattention and adult ADHD symptoms. Depressive symptoms fully mediated the path from anxiety to inattention, especially in those who report severe childhood traumatic experiences.

  20. Instabilities in power law gradient hardening materials

    DEFF Research Database (Denmark)

    Niordson, Christian Frithiof; Tvergaard, Viggo

    2005-01-01

    Tension and compression instabilities are investigated for specimens with dimensions in the micron range. A finite strain generalization of a higher order strain gradient plasticity theory is implemented in a finite element scheme capable of modeling power law hardening materials. Effects...... of gradient hardening are found to delay the onset of localization under plane strain tension, and significantly reduce strain gradients in the localized zone. For plane strain compression gradient hardening is found to increase the load-carrying capacity significantly....

  1. Power Play: The Dynamics of Power and Interpersonal Communication in Higher Education as Reflected in David Mamet's "Oleanna"

    Science.gov (United States)

    Chiaramonte, Peter

    2014-01-01

    David Mamet's play "Oleanna" may be infamous for reasons that do not do justice to the play's real accomplishments. One reason for the controversy is the author's apparent focus on sexual harassment. The play is not about sexual harassment. It is about power. And in particular the power of language to shape relationships…

  2. Dimensional response of CANDU fuel to power changes

    Energy Technology Data Exchange (ETDEWEB)

    Fehrenbach, P J [Fuel Engineering Branch, Chalk River Nuclear Laboratories, Atomic Energy of Canada Limited, Chalk River, ON (Canada); Hastings, I J; Morel, P A; Sage, R D; Smith, A D [Fuel Materials Branch, Chalk River Nuclear Laboratories, Atomic Energy of Canada Limited, Chalk River, ON (Canada)

    1983-06-01

    The introduction of CANLUB-coated fuel cladding, modified fuel management schemes, and revisions to the sequence of control rod movements, have eliminated power ramping fuel failures in CANDU power reactors. However, an irradiation program continues at Chalk River Nuclear Laboratories to determine the effect of various design and operating parameters on the dimensional response of UO{sub 2} fuel elements to power changes, over a range of conditions outside those normally experienced by CANDU power reactor fuel. We have investigated the effect of power changes on element diameter for UO{sub 2} fuel with starting densities of 10.6 and 10.8 Mg/m{sup 3} clad in 0.4 mm thick Zircaloy, at burnups from 0 to 100 MW.h/kg U. Element diameter measurements were obtained at power using an In-Reactor Diameter Measuring Rig (IRDMR). Rates of power change over the range 0.0005 to 0.03 kW.m{sup -1}.s{sup -1} were achieved by a combination of reactor power control and use of a Helium-3 power cycling facility. Total diameter increases in unirradiated elements were about 1% at pellet interface locations for both fuel densities during the initial power increase to 60 kW/m. Diameter changes during subsequent power cycles of these elements from 55 to 100% maximum power were significantly larger for the higher density fuel, ranging from 0.3 to 0.5% compared to less than 0.1% for the standard density (10.6 Mg/m{sup 3}) fuel. In elements pre-irradiated at 27 kW/m to burnups of about 100 MW.h/kg U prior to power ramping, the diameter increases measured after ramping to 55 kW/m also varied with starting fuel density. Diameter changes at pellet interface locations were about 0.9% and 0.6% for higher density and standard density fuel respectively. (author)

  3. Higher operational safety of nuclear power plants by evaluating the behaviour of operating personnel

    International Nuclear Information System (INIS)

    Mertins, M.; Glasner, P.

    1990-01-01

    In the GDR power reactors have been operated since 1966. Since that time operational experiences of 73 cumulative reactor years have been collected. The behaviour of operating personnel is an essential factor to guarantee the safety of operation of the nuclear power plant. Therefore a continuous analysis of the behaviour of operating personnel has been introduced at the GDR nuclear power plants. In the paper the overall system of the selection, preparation and control of the behaviour of nuclear power plant operating personnel is presented. The methods concerned are based on recording all errors of operating personnel and on analyzing them in order to find out the reasons. The aim of the analysis of reasons is to reduce the number of errors. By a feedback of experiences the nuclear safety of the nuclear power plant can be increased. All data necessary for the evaluation of errors are recorded and evaluated by a computer program. This method is explained thoroughly in the paper. Selected results of error analysis are presented. It is explained how the activities of the personnel are made safer by means of this analysis. Comparisons with other methods are made. (author). 3 refs, 4 figs

  4. Velocity- and power-load relationships of the bench pull vs. bench press exercises.

    Science.gov (United States)

    Sánchez-Medina, L; González-Badillo, J J; Pérez, C E; Pallarés, J G

    2014-03-01

    This study compared the velocity- and power-load relationships of the antagonistic upper-body exercises of prone bench pull (PBP) and bench press (BP). 75 resistance-trained athletes performed a progressive loading test in each exercise up to the one-repetition maximum (1RM) in random order. Velocity and power output across the 30-100% 1RM were significantly higher for PBP, whereas 1RM strength was greater for BP. A very close relationship was observed between relative load and mean propulsive velocity for both BP (R2=0.97) and PBP (R2=0.94) which enables us to estimate %1RM from velocity using the obtained prediction equations. Important differences in the load that maximizes power output (Pmax) and the power profiles of both exercises were found according to the outcome variable used: mean (MP), peak (PP) or mean propulsive power (MPP). When MP was considered, the Pmax load was higher (56% BP, 70% PBP) than when PP (37% BP, 41% PBP) or MPP (37% BP, 46% PBP) were used. For each variable there was a broad range of loads at which power output was not significantly different. The differing velocity- and power-load relationships between PBP and BP seem attributable to the distinct muscle architecture and moment arm levers involved in these exercises. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Laboratory- and Field-Based Assessment of Maximal Aerobic Power of Elite Stand-Up Paddle-Board Athletes.

    Science.gov (United States)

    Schram, Ben; Hing, Wayne; Climstein, Mike

    2016-01-01

    Stand-up paddle boarding (SUP) is a rapidly growing sport and recreational activity for which only anecdotal evidence exists on its proposed health, fitness, and injury-rehabilitation benefits. 10 internationally and nationally ranked elite SUP athletes. Participants were assessed for their maximal aerobic power on an ergometer in a laboratory and compared with other water-based athletes. Field-based assessments were subsequently performed using a portable gas-analysis system, and a correlation between the 2 measures was performed. Maximal aerobic power (relative) was significantly higher (P = .037) when measured in the field with a portable gas-analysis system (45.48 ± 6.96 mL · kg(-1) · min(-1)) than with laboratory-based metabolic-cart measurements (43.20 ± 6.67 mL · kg(-1) · min(-1)). There was a strong, positive correlation (r = .907) between laboratory and field maximal aerobic power results. Significantly higher (P = .000) measures of SUP paddling speed were found in the field than with the laboratory ergometer (+42.39%). There were no significant differences in maximal heart rate between the laboratory and field settings (P = .576). The results demonstrate the maximal aerobic power representative of internationally and nationally ranked SUP athletes and show that SUP athletes can be assessed for maximal aerobic power in the laboratory with high correlation to field-based measures. The field-based portable gas-analysis unit has a tendency to consistently measure higher oxygen consumption. Elite SUP athletes display aerobic power outputs similar to those of other upper-limb-dominant elite water-based athletes (surfing, dragon-boat racing, and canoeing).

  6. Radiation exposure potential from coal-fired power plants in Romania

    International Nuclear Information System (INIS)

    Botezatu, E.; Grecea, C.; Botezatu, G.; Capitanu, O.; Peic, T.; Sandor, G.

    1996-01-01

    In the investigated power plants they burn brown coal, lignite and/or mixture of different kinds of coal: brown coal, lignite, pit coal, pitch coal, bituminous coal. The activity concentrations measured in the coal samples varied over two orders of magnitude. The natural radionuclide concentrations in fly ash are significantly higher than the corresponding Concentrations in the coal. The normalized discharged activities for the investigated power plants are much higher than those estimated in the UNSCEAR 1988 Report for typical old and modern plants. Firstly, accounting for this is the low ash retention efficiency of the particulate control devices of power stations, especially for the older ones, and secondly, the high ash content of the coal: 26-60%. The low quality of coal leads to the higher coal consumption; thus the combustion of up to 20.109 Kg of coal is required to produce 1 Gwa of electrical energy. As a result, the activities of radon-222 and of radon-220 released per Gwa have been assessed at 25 to 770 GBq. (author)

  7. Significant enhancement in thermoelectric performance of nanostructured higher manganese silicides synthesized employing a melt spinning technique.

    Science.gov (United States)

    Muthiah, Saravanan; Singh, R C; Pathak, B D; Avasthi, Piyush Kumar; Kumar, Rishikesh; Kumar, Anil; Srivastava, A K; Dhar, Ajay

    2018-01-25

    The limited thermoelectric performance of p-type Higher Manganese Silicides (HMS) in terms of their low figure-of-merit (ZT), which is far below unity, is the main bottle-neck for realising an efficient HMS based thermoelectric generator, which has been recognized as the most promising material for harnessing waste-heat in the mid-temperature range, owing to its thermal stability, earth-abundant and environmentally friendly nature of its constituent elements. We report a significant enhancement in the thermoelectric performance of nanostructured HMS synthesized using rapid solidification by optimizing the cooling rates during melt-spinning followed by spark plasma sintering of the resulting melt-spun ribbons. By employing this experimental strategy, an unprecedented ZT ∼ 0.82 at 800 K was realized in spark plasma sintered 5 at% Al-doped MnSi 1.73 HMS, melt spun at an optimized high cooling rate of ∼2 × 10 7 K s -1 . This enhancement in ZT represents a ∼25% increase over the best reported values thus far for HMS and primarily originates from a nano-crystalline microstructure consisting of a HMS matrix (20-40 nm) with excess Si (3-9 nm) uniformly distributed in it. This nanostructure, resulting from the high cooling rates employed during the melt-spinning of HMS, introduces a high density of nano-crystallite boundaries in a wide spectrum of nano-scale dimensions, which scatter the low-to-mid-wavelength heat-carrying phonons. This abundant phonon scattering results in a significantly reduced thermal conductivity of ∼1.5 W m -1 K -1 at 800 K, which primarily contributes to the enhancement in ZT.

  8. Impact of integrating wind power in the Norwegian power system

    International Nuclear Information System (INIS)

    Tande, John Olav

    2006-04-01

    Wind power may in the future constitute a significant part of the Norwegian electricity supply. 20 TWh annual wind generation is a realistic goal for 2020 assuming wind farms on-land and offshore. The development of grid codes for wind farms is sound. It is recognising that large wind farms are basically power plants and may participate in securing efficient and stable power system operation. Modern wind farms may control the reactive power or voltage as any other power plant, and may also control active power or frequency as long as wind conditions permits. Grid code requirements must however be carefully assessed and possibly adjusted over time aiming for overall least cost solutions. Development of wind farms are today to some degree hindered by conservative assumptions being made on operation of wind farms in areas with limited power transfer capacity. By accepting temporary grid congestions, however, a large increase installed wind power is viable. For grid congestion that appears a few hours per year only, the cost of lost generation will be modest and may be economic over the alternatives of limiting wind farm capacities or increasing the grid transfer capacity. Wind generation impact on power system operation and adequacy will be overall positive. Combining wind and hydro provides for a more stable annual energy supply than hydro alone, and wind generation will generally be higher in the winter period than in the summer. Wind will replace the generation with the highest operating cost, and reduce the average Nord Pool spot market price. 20 TWh wind will reduce price with about 3 oere/kWh and CO 2 emissions by 12-14 million tons for the case of replacing coal, and about 6 million tons for replacing natural gas. Wind impact on need for balancing power is small, i.e. the extra balancing cost is about 0,8 oere per kWh wind, and about half if investment in new reserve capacity is not needed. In summary this report demonstrates options for large scale integration

  9. Inconsistency of Minkowski higher-derivative theories

    Energy Technology Data Exchange (ETDEWEB)

    Aglietti, Ugo G. [Universita di Roma ' ' La Sapienza' ' , Dipartimento di Fisica, Rome (Italy); Anselmi, Damiano [Universita di Pisa, Dipartimento di Fisica ' ' Enrico Fermi' ' , Pisa (Italy); INFN, Sezione di Pisa, Pisa (Italy)

    2017-02-15

    We show that Minkowski higher-derivative quantum field theories are generically inconsistent, because they generate nonlocal, non-hermitian ultraviolet divergences, which cannot be removed by means of standard renormalization procedures. By ''Minkowski theories'' we mean theories that are defined directly in Minkowski spacetime. The problems occur when the propagators have complex poles, so that the correlation functions cannot be obtained as the analytic continuations of their Euclidean versions. The usual power counting rules fail and are replaced by much weaker ones. Self-energies generate complex divergences proportional to inverse powers of D'Alembertians. Three-point functions give more involved nonlocal divergences, which couple to infrared effects. We illustrate the violations of the locality and hermiticity of counterterms in scalar models and higher-derivative gravity. (orig.)

  10. Tribes and Territories in the 21st Century: Rethinking the Significance of Disciplines in Higher Education. International Studies in Higher Education

    Science.gov (United States)

    Trowler, Paul, Ed.; Saunders, Murray, Ed.; Bamber, Veronica, Ed.

    2012-01-01

    The "tribes and territories" metaphor for the cultures of academic disciplines and their roots in different knowledge characteristics has been used by those interested in university life and work since the early 1990s. This book draws together research, data and theory to show how higher education has gone through major change since then…

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

    International Nuclear Information System (INIS)

    Yinong Li; Dong Wang

    2006-01-01

    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)

  12. Power system reliability impacts of wind generation and operational reserve requirements

    Directory of Open Access Journals (Sweden)

    Esteban Gil

    2015-06-01

    Full Text Available Due to its variability, wind generation integration presents a significant challenge to power system operators in order to maintain adequate reliability levels while ensuring least cost operation. This paper explores the trade-off between the benefits associated to a higher wind penetration and the additional operational reserve requirements that they impose. Such exploration is valued in terms of its effect on power system reliability, measured as an amount of unserved energy. The paper also focuses on how changing the Value of Lost Load (VoLL can be used to attain different reliability targets, and how wind power penetration and the diversity of the wind energy resource will impact quality of supply (in terms of instances of unserved energy. The evaluation of different penetrations of wind power generation, different wind speed profiles, wind resource diversity, and different operational reserve requirements, is conducted on the Chilean Northern Interconnected System (SING using statistical modeling of wind speed time series and computer simulation through a 24-hour ahead unit commitment algorithm and a Monte Carlo simulation scheme. Results for the SING suggest that while wind generation can significantly reduce generation costs, it can also imply higher security costs to reach acceptable reliability levels.

  13. Relationship Power, Sexual Decision Making, and HIV Risk Among Midlife and Older Women.

    Science.gov (United States)

    Altschuler, Joanne; Rhee, Siyon

    2015-01-01

    The number of midlife and older women with HIV/AIDS is high and increasing, especially among women of color. This article addresses these demographic realities by reporting on findings about self-esteem, relationship power, and HIV risk from a pilot study of midlife and older women. A purposive sample (N = 110) of ethnically, economically, and educationally diverse women 40 years and older from the Greater Los Angeles Area was surveyed to determine their levels of self-esteem, general relationship power, sexual decision-making power, safer sex behaviors, and HIV knowledge. Women with higher levels of self-esteem exercised greater power in their relationships with their partner. Women with higher levels of general relationship power and self-esteem tend to exercise greater power in sexual decision making, such as having sex and choosing sexual acts. Income and sexual decision-making power were statistically significant in predicting the use of condoms. Implications and recommendations for future HIV/AIDS research and intervention targeting midlife and older women are presented.

  14. Coordinated control of wind power plants in offshore HVDC grids

    DEFF Research Database (Denmark)

    Sakamuri, Jayachandra N.

    2017-01-01

    power between different countries, and different synchronous areas. It is very likely that they will then be combined with offshore wind power plant (OWPP) connections in the North Sea, transforming it in a multi terminal DC (MTDC) grid and, therefore, in a fully meshed offshore DC grid in near future......During the recent years, there has been a significant penetration of offshore wind power into the power system and this trend is expected to continue in the future. The North Sea in Europe has higher potential for offshore wind power; therefore, the North Seas Countries' Offshore Grid initiative....... However, increased penetration of offshore wind power into the power system poses several challenges to its security. This thesis deals with two main research challenges, (1) Develop, and analyze the coordinated control strategies for AC voltage and reactive power control in the cluster of OWPPs connected...

  15. Crystalline lens power and refractive error.

    Science.gov (United States)

    Iribarren, Rafael; Morgan, Ian G; Nangia, Vinay; Jonas, Jost B

    2012-02-01

    To study the relationships between the refractive power of the crystalline lens, overall refractive error of the eye, and degree of nuclear cataract. All phakic participants of the population-based Central India Eye and Medical Study with an age of 50+ years were included. Calculation of the refractive lens power was based on distance noncycloplegic refractive error, corneal refractive power, anterior chamber depth, lens thickness, and axial length according to Bennett's formula. The study included 1885 subjects. Mean refractive lens power was 25.5 ± 3.0 D (range, 13.9-36.6). After adjustment for age and sex, the standardized correlation coefficients (β) of the association with the ocular refractive error were highest for crystalline lens power (β = -0.41; P lens opacity grade (β = -0.42; P lens power (β = -0.95), lower corneal refractive power (β = -0.76), higher lens thickness (β = 0.30), deeper anterior chamber (β = 0.28), and less marked nuclear lens opacity (β = -0.05). Lens thickness was significantly lower in eyes with greater nuclear opacity. Variations in refractive error in adults aged 50+ years were mostly influenced by variations in axial length and in crystalline lens refractive power, followed by variations in corneal refractive power, and, to a minor degree, by variations in lens thickness and anterior chamber depth.

  16. A Low-Power and Low-Voltage Power Management Strategy for On-Chip Micro Solar Cells

    Directory of Open Access Journals (Sweden)

    Ismail Cevik

    2015-01-01

    Full Text Available Fundamental characteristics of on-chip micro solar cell (MSC structures were investigated in this study. Several MSC structures using different layers in three different CMOS processes were designed and fabricated. Effects of PN junction structure and process technology on solar cell performance were measured. Parameters for low-power and low-voltage implementation of power management strategy and boost converter based circuits utilizing fractional voltage maximum power point tracking (FVMPPT algorithm were determined. The FVMPPT algorithm works based on the fraction between the maximum power point operation voltage and the open circuit voltage of the solar cell structure. This ratio is typically between 0.72 and 0.78 for commercially available poly crystalline silicon solar cells that produce several watts of power under typical daylight illumination. Measurements showed that the fractional voltage ratio is much higher and fairly constant between 0.82 and 0.85 for on-chip mono crystalline silicon micro solar cell structures that produce micro watts of power. Mono crystalline silicon solar cell structures were observed to result in better power fill factor (PFF that is higher than 74% indicating a higher energy harvesting efficiency.

  17. Implementing low power consumption in standby mode in the case of power supplies with power factor correction

    OpenAIRE

    Martín, Kevin; F., Pablo; G., Diego; Sebastián, Javier; Álvarez, Santiago

    2017-01-01

    This work analyzes different options to implement low power consumption in Switching Mode Power Supplies (SMPSs) with Power Factor Correction (PFC) when they are in standby mode. The standard SMPSs for power levels higher than 100 W are made up of two stages: a classical PFC stage based on a Boost Converter operating in the Continuous Conduction Mode and a second stage based on any type of isolated DC-DC converter. The value of the resistive sensors needed by the PFC control stage determines ...

  18. Wind Power Prediction Considering Nonlinear Atmospheric Disturbances

    Directory of Open Access Journals (Sweden)

    Yagang Zhang

    2015-01-01

    Full Text Available This paper considers the effect of nonlinear atmospheric disturbances on wind power prediction. A Lorenz system is introduced as an atmospheric disturbance model. Three new improved wind forecasting models combined with a Lorenz comprehensive disturbance are put forward in this study. Firstly, we define the form of the Lorenz disturbance variable and the wind speed perturbation formula. Then, different artificial neural network models are used to verify the new idea and obtain better wind speed predictions. Finally we separately use the original and improved wind speed series to predict the related wind power. This proves that the corrected wind speed provides higher precision wind power predictions. This research presents a totally new direction in the wind prediction field and has profound theoretical research value and practical guiding significance.

  19. Solar dynamic power system definition study

    Science.gov (United States)

    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.

  20. Study on EEG power and coherence in patients with mild cognitive impairment during working memory task

    Institute of Scientific and Technical Information of China (English)

    JIANG Zheng-yan

    2005-01-01

    To investigate the features of electroencephalography (EEG) power and coherence at rest and during a working memory task of patients with mild cognitive impairment (MCI). Thirty-five patients (17 males, 18 females; 52~71 years old) and 34 sex- and age-matched controls (17 males, 17 females; 51~63 years old) were recruited in the present study. Mini-Mental State Examination (MMSE) of 35 patients with MCI and 34 normal controls revealed that the scores of MCI patients did not differ significantly from those of normal controls (P>0.05). Then, EEGs at rest and during working memory task with three levels of working memory load were recorded. The EEG power was computed over 10 channels: right and left frontal (F3, F4), central (C3,C4), parietal (P3, P4), temporal (TS, T6) and occipital (O1, O2); inter-hemispheric coherences were computed from five electrode pairs of F3-F4, C3-C4, P3-P4, T5-T6 and O1-O2 for delta (1.0~3.5 Hz), theta (4.0~7.5 Hz), alpha-1 (8.0~10.0 Hz), alpha-2 (10.5~13.0 Hz), beta-1 (13.5~18.0 Hz) and beta-2 (18.5~30.0 Hz) frequency bands. All values of the EEG power of MCI patients were found to be higher than those of normal controls at rest and during working memory tasks. Furthermore, the values of EEG power in the theta, alpha-1, alpha-2 and beta-1 bands of patients with MCI were significantly high (P<0.05) in comparison with those of normal controls. Correlation analysis indicated a significant negative correlation between the EEG powers and MMSE scores. In addition, during working memory tasks, the EEG coherences in all bands were significantly higher in the MCI group in comparison with those in the control group (P<0.05). However, there was no significant difference in EEG coherences between two groups at rest. These findings comprise evidence that MCI patients have higher EEG power at rest, and higher EEG power and coherence during working conditions. It suggests that MCI may be associated with compensatory processes at

  1. Novel partial-subsidence tower-type boiler design in an ultra-supercritical power plant

    International Nuclear Information System (INIS)

    Xu, Gang; Xu, Cheng; Yang, Yongping; Fang, Yaxiong; Zhou, Luyao; Zhang, Kai

    2014-01-01

    Highlights: • The two-pass type and tower-type boilers were compared. • A novel partial-subsidence tower-type boiler design was proposed. • Thermodynamic and economic analyses were quantitatively conducted. • The application of the partial-subsidence boiler to a 700 °C stage unit was further analyzed. - Abstract: An increasing number of tower-type boilers have been applied to ultra-supercritical power plants because of the simple design of the membrane walls and the smooth increase in temperature of such boilers. Nevertheless, the significant height and long steam pipelines of this boiler type will expand the power plant investment cost and increase steam-side pressure losses, especially for higher parameters units requiring high costs of nickel-based alloy materials. Thus, a novel partial-subsidence tower-type boiler design was proposed. In this boiler type, nearly 1/2–2/3 of the boiler height was embedded underground to reduce the height of the boiler and the length of the steam pipelines significantly. Thermodynamic and economic analyses were conducted on a state-of-the-art 1000 MW ultra-supercritical power plant and a prospective 700 °C-stage double reheat power plant. Results showed that the proposed tower-type boiler design could result in a 0.1% point increase in net efficiency and a $0.56/MW h reduction in the cost of electricity in a 1000 MW power plant. This economic benefit was enhanced for power plants with higher steam parameters and larger capacity. The concept of the proposed boiler design may provide a promising method for tower-type boiler applications, especially in new-generation double reheat plants with higher parameters

  2. Rolling resistance and propulsion efficiency of manual and power-assisted wheelchairs.

    Science.gov (United States)

    Pavlidou, Efthymia; Kloosterman, Marieke G M; Buurke, Jaap H; Rietman, Johan S; Janssen, Thomas W J

    2015-11-01

    Rolling resistance is one of the main forces resisting wheelchair propulsion and thus affecting stress exerted on the upper limbs. The present study investigates the differences in rolling resistance, propulsion efficiency and energy expenditure required by the user during power-assisted and manual propulsion. Different tire pressures (50%, 75%, 100%) and two different levels of motor assistance were tested. Drag force, energy expenditure and propulsion efficiency were measured in 10 able-bodied individuals under different experimental settings on a treadmill. Results showed that drag force levels were significantly higher in the 50%, compared to the 75% and 100% inflation conditions. In terms of wheelchair type, the manual wheelchair displayed significantly lower drag force values than the power-assisted one. The use of extra-power-assisted wheelchair appeared to be significantly superior to conventional power-assisted and manual wheelchairs concerning both propulsion efficiency and energy expenditure required by the user. Overall, the results of the study suggest that the use of power-assisted wheelchair was more efficient and required less energy input by the user, depending on the motor assistance provided. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  3. Wind speed power spectrum analysis for Bushland, Texas

    Energy Technology Data Exchange (ETDEWEB)

    Eggleston, E.D. [USDA-Agricultural Research Service, Bushland, TX (United States)

    1996-12-31

    Numerous papers and publications on wind turbulence have referenced the wind speed spectrum presented by Isaac Van der Hoven in his article entitled Power Spectrum of Horizontal Wind Speed Spectrum in the Frequency Range from 0.0007 to 900 Cycles per Hour. Van der Hoven used data measured at different heights between 91 and 125 meters above the ground, and represented the high frequency end of the spectrum with data from the peak hour of hurricane Connie. These facts suggest we should question the use of his power spectrum in the wind industry. During the USDA - Agricultural Research Service`s investigation of wind/diesel system power storage, using the appropriate wind speed power spectrum became a significant issue. We developed a power spectrum from 13 years of hourly average data, 1 year of 5 minute average data, and 2 particularly gusty day`s 1 second average data all collected at a height of 10 meters. While the general shape is similar to the Van der Hoven spectrum, few of his peaks were found in the Bushland spectrum. While higher average wind speeds tend to suggest higher amplitudes in the high frequency end of the spectrum, this is not always true. Also, the high frequency end of the spectrum is not accurately described by simple wind statistics such as standard deviation and turbulence intensity. 2 refs., 5 figs., 1 tab.

  4. Magnetic tunnel junction thermocouple for thermoelectric power harvesting

    Science.gov (United States)

    Böhnert, T.; Paz, E.; Ferreira, R.; Freitas, P. P.

    2018-05-01

    The thermoelectric power generated in magnetic tunnel junctions (MTJs) is determined as a function of the tunnel barrier thickness for a matched electric circuit. This study suggests that lower resistance area product and higher tunnel magnetoresistance will maximize the thermoelectric power output of the MTJ structures. Further, the thermoelectric behavior of a series of two MTJs, a MTJ thermocouple, is investigated as a function of its magnetic configurations. In an alternating magnetic configurations the thermovoltages cancel each other, while the magnetic contribution remains. A large array of MTJ thermocouples could amplify the magnetic thermovoltage signal significantly.

  5. A novel approach to improving the radiation hardness of SiC Power Devices, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Silicon Carbide Technology for power semiconductors offers a significant improvement in capability that will allow systems to operate at higher voltages and...

  6. Association between power law coefficients of the anatomical noise power spectrum and lesion detectability in breast imaging modalities

    Science.gov (United States)

    Chen, Lin; Abbey, Craig K.; Boone, John M.

    2013-03-01

    Previous research has demonstrated that a parameter extracted from a power function fit to the anatomical noise power spectrum, β, may be predictive of breast mass lesion detectability in x-ray based medical images of the breast. In this investigation, the value of β was compared with a number of other more widely used parameters, in order to determine the relationship between β and these other parameters. This study made use of breast CT data sets, acquired on two breast CT systems developed in our laboratory. A total of 185 breast data sets in 183 women were used, and only the unaffected breast was used (where no lesion was suspected). The anatomical noise power spectrum computed from two-dimensional region of interests (ROIs), was fit to a power function (NPS(f) = α f-β), and the exponent parameter (β) was determined using log/log linear regression. Breast density for each of the volume data sets was characterized in previous work. The breast CT data sets analyzed in this study were part of a previous study which evaluated the receiver operating characteristic (ROC) curve performance using simulated spherical lesions and a pre-whitened matched filter computer observer. This ROC information was used to compute the detectability index as well as the sensitivity at 95% specificity. The fractal dimension was computed from the same ROIs which were used for the assessment of β. The value of β was compared to breast density, detectability index, sensitivity, and fractal dimension, and the slope of these relationships was investigated to assess statistical significance from zero slope. A statistically significant non-zero slope was considered to be a positive association in this investigation. All comparisons between β and breast density, detectability index, sensitivity at 95% specificity, and fractal dimension demonstrated statistically significant association with p performance. Specifically, lower values of β were associated with lower breast density

  7. Quality Assurance in Higher Education: Reflection, Criticism, and Change

    Science.gov (United States)

    Yingqiang, Zhang; Yongjian, Su

    2016-01-01

    Quality assurance in modern higher education is both an accountability-oriented ideology and a technological method. It has also evolved into a increasingly rationalist and professionalized power mechanism. Its advocacy of compliance, technological mythology, and imbalance between power and responsibility are inherent disadvantages of higher…

  8. Laser power beaming: an emerging technology for power transmission and propulsion in space

    Science.gov (United States)

    Bennett, Harold E.

    1997-05-01

    A ground based laser beam transmitted to space can be used as an electric utility for satellites. It can significantly increase the electric power available to operate a satellite or to transport it from low earth orbit (LEO) to mid earth or geosynchronous orbits. The increase in electrical power compared to that obtainable from the sun is as much as 1000% for the same size solar panels. An increase in satellite electric power is needed to meet the increasing demands for power caused by the advent of 'direct to home TV,' for increased telecommunications, or for other demands made by the burgeoning 'space highway.' Monetary savings as compared to putting up multiple satellites in the same 'slot' can be over half a billion dollars. To obtain propulsion, the laser power can be beamed through the atmosphere to an 'orbit transfer vehicle' (OTV) satellite which travels back and forth between LEO and higher earth orbits. The OTV will transport the satellite into orbit as does a rocket but does not require the heavy fuel load needed if rocket propulsion is used. Monetary savings of 300% or more in launch costs are predicted. Key elements in the proposed concept are a 100 to 200 kW free- electron laser operating at 0.84 m in the photographic infrared region of the spectrum and a novel adaptive optic telescope.

  9. Power system reliability enhancement by using PowerformerTM

    Directory of Open Access Journals (Sweden)

    Rahmat-Allah Hooshmand

    2009-01-01

    Full Text Available A high-voltage generator PowerformerTM is a new generation of the AC generators. The most significant advantages of these PowerformerTM are their direct connection to high-voltage grid, higher availability, and more reactive power margin, short term overloading capacity and removing the power transformer from the structure of the power plant. In this paper, the installation effect of these generators on the power system reliability is investigated. The amount of the effects depends on the type and location of the power plant, location of the PowerformerTM, the size of load and network topology. For this purpose, in the 6-bus IEEE RBTS system, the conventional generators are replaced by these new PowerformerTM and then, the reliability indices are evaluated. The simulation results show that the reliability indices such as the expected duration of load curtailment (EDLC and the expected energy not served (EENS are improved. .

  10. Higher prices at Canadian gas pumps: international crude oil prices or local market concentration? An empirical investigation

    International Nuclear Information System (INIS)

    Anindya Sen

    2003-01-01

    There is little consensus on whether higher retail gasoline prices in Canada are the result of international crude oil price fluctuations or local market power exercised by large vertically-integrated firms. I find that although both increasing local market concentration and higher average monthly wholesale prices are positively and significantly associated with higher retail prices, wholesale prices are more important than local market concentration. Similarly, crude oil prices are more important than the number of local wholesalers in determining wholesale prices. These results suggest that movements in gasoline prices are largely the result of input price fluctuations rather than local market structure. (author)

  11. Prospects for advanced coal-fuelled fuel cell power plants

    International Nuclear Information System (INIS)

    Jansen, D.; Laag, P.C. van der; Oudhuis, A.B.J.; Ribberink, J.S.

    1994-01-01

    As part of ECN's in-house R and D programmes on clean energy conversion systems with high efficiencies and low emissions, system assessment studies have been carried out on coal gasification power plants integrated with high-temperature fuel cells (IGFC). The studies also included the potential to reduce CO 2 emissions, and to find possible ways for CO 2 extraction and sequestration. The development of this new type of clean coal technology for large-scale power generation is still far off. A significant market share is not envisaged before the year 2015. To assess the future market potential of coal-fuelled fuel cell power plants, the promise of this fuel cell technology was assessed against the performance and the development of current state-of-the-art large-scale power generation systems, namely the pulverized coal-fired power plants and the integrated coal gasification combined cycle (IGCC) power plants. With the anticipated progress in gas turbine and gas clean-up technology, coal-fuelled fuel cell power plants will have to face severe competition from advanced IGCC power plants, despite their higher efficiency. (orig.)

  12. Advanced Radioisotope Power Conversion Technology Research and Development

    Science.gov (United States)

    Wong, Wayne A.

    2004-01-01

    NASA's Radioisotope Power Conversion Technology program is developing next generation power conversion technologies that will enable future missions that have requirements that cannot be met by either the ubiquitous photovoltaic systems or by current Radioisotope Power System (RPS) technology. Performance goals of advanced radioisotope power systems include improvement over the state-of-practice General Purpose Heat Source/Radioisotope Thermoelectric Generator by providing significantly higher efficiency to reduce the number of radioisotope fuel modules, and increase specific power (watts/kilogram). Other Advanced RPS goals include safety, long-life, reliability, scalability, multi-mission capability, resistance to radiation, and minimal interference with the scientific payload. NASA has awarded ten contracts in the technology areas of Brayton, Stirling, Thermoelectric, and Thermophotovoltaic power conversion including five development contracts that deal with more mature technologies and five research contracts. The Advanced RPS Systems Assessment Team includes members from NASA GRC, JPL, DOE and Orbital Sciences whose function is to review the technologies being developed under the ten Radioisotope Power Conversion Technology contracts and assess their relevance to NASA's future missions. Presented is an overview of the ten radioisotope power conversion technology contracts and NASA's Advanced RPS Systems Assessment Team.

  13. Serial powering of pixel modules

    International Nuclear Information System (INIS)

    Stockmanns, Tobias; Fischer, Peter; Huegging, Fabian; Peric, Ivan; Runolfsson, O.; Wermes, Norbert

    2003-01-01

    Modern pixel detectors for the next generation of high-energy collider experiments like LHC use readout electronics in deep sub-micron technology. Chips in this technology need a low supply voltage of 2-2.5 V alongside high current consumption to achieve the desired performance. The high supply current leads to significant voltage drops in the long and low mass supply cables so that voltage fluctuations at the chips are induced, when the supply current changes. This problem scales with the number of modules when connected in parallel to the power supplies. An alternative powering scheme connects several modules in series resulting in a higher supply voltage but a lower current consumption of the chain and therefore a much lower voltage drop in the cables. In addition the amount of cables needed to supply the detector is vastly reduced. The concept and features of serial powering are presented and studies of the implementation of this technology as an alternative for the ATLAS pixel detector are shown. In particular, it is shown that the potential risk of powering in series can be addressed and eliminated

  14. Effects of Transverse Power Distribution on Fuel Temperature

    International Nuclear Information System (INIS)

    Jo, Daeseong; Park, Jonghark; Seo, Chul Gyo; Chae, Heetaek

    2014-01-01

    In the present study, transverse power distributions with segments of 4 and 18 are evaluated. Based on the power distribution, the fuel temperatures are evaluated with a consideration of lateral heat conduction. In the present study, the effect of the transverse power distribution on the fuel temperature is investigated. The transverse power distributions with variation of fuel segment number are evaluated. The maximum power peaking with 12 segments is higher than that with 4 segments. Based on the calculation, 6-order polynomial is generated to express the transverse power distributions. The maximum power peaking factor increases with segments. The averaged power peaking is 2.10, and the maximum power peaking with 18 segments is 2.80. With the uniform power distribution, the maximum fuel temperature is found in the middle of the fuel. As the power near the side ends of the fuel increases, the maximum fuel temperature is found near the side ends. However, the maximum fuel temperature is not found where the maximum transverse power is. This is because the high power locally released from the edge of the fuel is laterally conducted to the cladding. As a result of the present study, it can be concluded that the effect of the high power peaking at the edge of the fuel on the fuel outer wall temperature is not significant

  15. Powered two-wheeler drivers' risk of hitting a pedestrian in towns.

    Science.gov (United States)

    Clabaux, Nicolas; Fournier, Jean-Yves; Michel, Jean-Emmanuel

    2014-12-01

    The risk of collision between pedestrians and powered two-wheelers is poorly understood today. The objective of this research is to determine the risk for powered two-wheeler drivers of hitting and injuring a pedestrian per kilometer driven in towns and to compare this risk with that run by four-wheeled vehicle drivers. Using the bodily injury accidents recorded by the police on nine roads in the city of Marseille in 2011 and a campaign of observations of powered two-wheeler traffic, we estimated the risk per kilometer driven by powered two-wheeler drivers of hitting a pedestrian and compared it with the risk run by four-wheeled vehicle drivers. The results show that the risk for powered two-wheeler drivers of hitting and injuring a pedestrian is significantly higher than the risk run by four-wheeled vehicle drivers. On the nine roads studied, it is on average 3.33 times higher (95% CI: 1.63; 6.78). Taking four more years into account made it possible to consolidate these results and to tighten the confidence interval. There does indeed seem to be problems in the interactions between pedestrians and powered two-wheeler users in urban traffic. These interaction problems lead to a higher risk of hitting and injuring a pedestrian for powered two-wheeler drivers than for four-wheeled vehicle drivers. The analysis of the police reports suggests that part of this increased risk comes from filtering maneuvers by powered two-wheelers. Possible countermeasures deal with the urban street layout. Measures consisting in reducing the width and the number of traffic lanes to a strict minimum and installing medians or pedestrian islands could be an effective way for the prevention of urban accidents between pedestrians and powered two-wheelers. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.

  16. The Balance Between Higher Education Autonomy and Public Quality Assurance:Development of the Portuguese System for Teacher Education Accreditation

    Directory of Open Access Journals (Sweden)

    Bártolo Campos

    2004-12-01

    Full Text Available The accreditation systems of higher education institutions and/or programs are becoming a policy measure used to find a balance between their autonomy and public assurance concerning the quality of the qualifications they award. This article analyses, from the point of view of this balance of power, the process of development of the Portuguese accreditation system aimed at providing public assurance that initial teacher education programs are more driven by social demand, namely by the changing school education needs. This was a political and cultural process rather than a merely rational and technical one. Thus the emergence of the need for, and possibility of, external pressure upon higher education institutions is related to the evolution of several social factors. On the other hand, the implementation of the accreditation system means a significant change for these institutions which implies new practices and comes into conflict with some of their values and with power sharing within and among them and with society. For these reasons a strategy of wide participation of significant stakeholders was deemed more suitable for the formulation, adoption and implementation of this new public policy. The way in which government, the accreditation body, and the significant stakeholders exercised their power in this process influenced the characteristics of the system, the rhythm of its implementation, and the abrupt governmental decision to put it on stand-by, until now.

  17. Replacement power costs due to nuclear-plant outages: a higher standard of care

    International Nuclear Information System (INIS)

    Gransee, M.F.

    1982-01-01

    This article examines recent state public utility commission cases that deal with the high costs of replacement power that utilities must purchase after a nuclear power plant outage. Although most commissions have approved such expenses, it may be that there is a trend toward splitting the costs of such expenses between ratepayer and stockholder. Commissions are demanding a management prudence test to determine the cause of the outage and whether it meets the reasonable man standard before allowing these costs to be passed along to ratepayers. Unless the standard is applied with flexibility, however, utility companies could invoke the defenses covering traditional common law negligence

  18. Electro-autotrophic synthesis of higher alcohols

    Science.gov (United States)

    Liao, James C.; Cho, Kwang Myung

    2016-11-01

    The disclosure provides a process that converts CO.sub.2 to higher alcohols (e.g. isobutanol) using electricity as the energy source. This process stores electricity (e.g. from solar energy, nuclear energy, and the like) in liquid fuels that can be used as high octane number gasoline substitutes. Instead of deriving reducing power from photosynthesis, this process derives reducing power from electrically generated mediators, either H.sub.2 or formate. H.sub.2 can be derived from electrolysis of water. Formate can be generated by electrochemical reduction of CO.sub.2. After delivering the reducing power in the cell, formate becomes CO.sub.2 and recycles back. Therefore, the biological CO.sub.2 fixation process can occur in the dark.

  19. Anomalous pH-Dependent Nanofluidic Salinity Gradient Power.

    Science.gov (United States)

    Yeh, Li-Hsien; Chen, Fu; Chiou, Yu-Ting; Su, Yen-Shao

    2017-12-01

    Previous studies on nanofluidic salinity gradient power (NSGP), where energy associated with the salinity gradient can be harvested with ion-selective nanopores, all suggest that nanofluidic devices having higher surface charge density should have higher performance, including osmotic power and conversion efficiency. In this manuscript, this viewpoint is challenged and anomalous counterintuitive pH-dependent NSGP behaviors are reported. For example, with equal pH deviation from its isoelectric point (IEP), the nanopore at pH IEP is shown to have smaller surface charge density but remarkably higher NSGP performance than that at pH > IEP. Moreover, for sufficiently low pH, the NSGP performance decreases with lowering pH (increasing nanopore charge density). As a result, a maximum osmotic power density as high as 5.85 kW m -2 can be generated along with a conversion efficiency of 26.3% achieved for a single alumina nanopore at pH 3.5 under a 1000-fold concentration ratio. Using the rigorous model with considering the surface equilibrium reactions on the pore wall, it is proved that these counterintuitive surface-charge-dependent NSGP behaviors result from the pH-dependent ion concentration polarization effect, which yields the degradation in effective concentration ratio across the nanopore. These findings provide significant insight for the design of next-generation, high-performance NSGP devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Higher Education and European Regionalism.

    Science.gov (United States)

    Paterson, Lindsay

    2001-01-01

    Speculates about the relationship between two fundamental social changes occurring in Europe: the development of a mass higher education system and the slow decay of the old states that were inherited from the 19th century, eroded from below by various movements for national and regional autonomy, and eroded from above by the growing power and…

  1. Increased power to weight ratio of piezoelectric energy harvesters through integration of cellular honeycomb structures

    International Nuclear Information System (INIS)

    Chandrasekharan, N; Thompson, L L

    2016-01-01

    The limitations posed by batteries have compelled the need to investigate energy harvesting methods to power small electronic devices that require very low operational power. Vibration based energy harvesting methods with piezoelectric transduction in particular has been shown to possess potential towards energy harvesters replacing batteries. Current piezoelectric energy harvesters exhibit considerably lower power to weight ratio or specific power when compared to batteries the harvesters seek to replace. To attain the goal of battery-less self-sustainable device operation the power to weight ratio gap between piezoelectric energy harvesters and batteries need to be bridged. In this paper the potential of integrating lightweight honeycomb structures with existing piezoelectric device configurations (bimorph) towards achieving higher specific power is investigated. It is shown in this study that at low excitation frequency ranges, replacing the solid continuous substrate of conventional bimorph with honeycomb structures of the same material results in a significant increase in power to weight ratio of the piezoelectric harvester. At higher driving frequency ranges it is shown that unlike the traditional piezoelectric bimorph with solid continuous substrate, the honeycomb substrate bimorph can preserve optimum global design parameters through manipulation of honeycomb unit cell parameters. Increased operating lifetime and design flexibility of the honeycomb core piezoelectric bimorph is demonstrated as unit cell parameters of the honeycomb structures can be manipulated to alter mass and stiffness properties of the substrate, resulting in unit cell parameter significantly influencing power generation. (paper)

  2. On minimally parametric primordial power spectrum reconstruction and the evidence for a red tilt

    International Nuclear Information System (INIS)

    Verde, Licia; Peiris, Hiranya

    2008-01-01

    The latest cosmological data seem to indicate a significant deviation from scale invariance of the primordial power spectrum when parameterized either by a power law or by a spectral index with non-zero 'running'. This deviation, by itself, serves as a powerful tool for discriminating among theories for the origin of cosmological structures such as inflationary models. Here, we use a minimally parametric smoothing spline technique to reconstruct the shape of the primordial power spectrum. This technique is well suited to searching for smooth features in the primordial power spectrum such as deviations from scale invariance or a running spectral index, although it would recover sharp features of high statistical significance. We use the WMAP three-year results in combination with data from a suite of higher resolution cosmic microwave background experiments (including the latest ACBAR 2008 release), as well as large-scale structure data from SDSS and 2dFGRS. We employ cross-validation to assess, using the data themselves, the optimal amount of smoothness in the primordial power spectrum consistent with the data. This minimally parametric reconstruction supports the evidence for a power law primordial power spectrum with a red tilt, but not for deviations from a power law power spectrum. Smooth variations in the primordial power spectrum are not significantly degenerate with the other cosmological parameters

  3. The Significance of a Building’s Energy Consumption Profiles for the Optimum Sizing of a Combined Heat and Power (CHP System—A Case Study for a Student Residence Hall

    Directory of Open Access Journals (Sweden)

    Khuram Pervez Amber

    2018-06-01

    Full Text Available University buildings, such as student residence halls with year-round consistent energy demands, offer strong opportunities for Combined Heat and Power (CHP systems. The economic and environmental feasibility of a CHP project is strongly linked with its optimum sizing. This study aims to undertake such an assessment for a CHP system for a student residence hall located in London, the United Kingdom (UK. The study also aims to undertake a sensitivity analysis to investigate the effect of different parameters on the project’s economics. Necessary data are collected via interviews with the University’s Energy Manager. Modeling of the CHP system is performed using the London South Bank University (LSBU, London, the UK CHP model. Results demonstrate that optimum sizing of CHP is crucial for achieving higher economic and environmental benefits and strongly depends on the authenticity of the energy consumption data, based on which the CHP is being sized. Use of incorrect energy data could result in an undersized or oversized CHP system, where an oversized system will result in higher negative results compared to an undersized system. Finally, Monto Carlo statistical analysis shows that electricity price is the significant factor that could affect the project’s economics. With an increasing spark gap, the payback period decreases, and vice versa.

  4. Economy and technology roles played by nuclear power

    International Nuclear Information System (INIS)

    Yamada, Eiji

    1985-01-01

    On the basis of the survey analysis made by Atomic Energy Commission on the roles in economy and technology played in the nuclear energy development and utilization, the following are described: economic roles in nuclear energy development and utilization (the present state of nuclear power industry in Japan and the economy effects); technological roles in the same (the present state of nuclear power technology in Japan and the technology effects). The economy effects in other areas are on higher level than in other industries etc. Then, in the technology effects, system technology and quality control in the nuclear power possess significant effects in other areas. While the nuclear energy development and utilization is important in Japan's energy security, it is contributing largely to the economy and society in Japan. (Mori, K.)

  5. Categorification and higher representation theory

    CERN Document Server

    Beliakova, Anna

    2017-01-01

    The emergent mathematical philosophy of categorification is reshaping our view of modern mathematics by uncovering a hidden layer of structure in mathematics, revealing richer and more robust structures capable of describing more complex phenomena. Categorified representation theory, or higher representation theory, aims to understand a new level of structure present in representation theory. Rather than studying actions of algebras on vector spaces where algebra elements act by linear endomorphisms of the vector space, higher representation theory describes the structure present when algebras act on categories, with algebra elements acting by functors. The new level of structure in higher representation theory arises by studying the natural transformations between functors. This enhanced perspective brings into play a powerful new set of tools that deepens our understanding of traditional representation theory. This volume exhibits some of the current trends in higher representation theory and the diverse te...

  6. The effects of training with loads that maximise power output and individualised repetitions vs. traditional power training.

    Directory of Open Access Journals (Sweden)

    J M Sarabia

    Full Text Available It has been suggested that strength training effects (i.e. neural or structural vary, depending on the total repetitions performed and velocity loss in each training set.The aim of this study is to compare the effects of two training programmes (i.e. one with loads that maximise power output and individualised repetitions, and the other following traditional power training.Twenty-five males were divided into three groups (optimum power [OP = 10], traditional training [TT = 9] and control group [CG = 6]. The training load used for OP was individualised using loads that maximised power output (41.7% ± 5.8 of one repetition maximum [1RM] and repetitions at maximum power (4 to 9 repetitions, or 'reps'. Volume (sets x repetitions was the same for both experimental groups, while intensity for TT was that needed to perform only 50% of the maximum number of possible repetitions (i.e. 61.1%-66.6% of 1RM. The training programme ran over 11 weeks (2 sessions per week; 4-5 sets per session; 3-minute rests between sets, with pre-, intermediate and post-tests which included: anthropometry, 1RM, peak power output (PPO with 30%, 40% and 50% of 1RM in the bench press throw, and salivary testosterone (ST and cortisol (SC concentrations. Rate of perceived exertion (RPE and power output were recorded in all sessions.Following the intermediate test, PPO was increased in the OP group for each load (10.9%-13.2%. Following the post-test, both experimental groups had increased 1RM (11.8%-13.8% and PPO for each load (14.1%-19.6%. Significant decreases in PPO were found for the TT group during all sets (4.9%-15.4%, along with significantly higher RPE (37%.OP appears to be a more efficient method of training, with less neuromuscular fatigue and lower RPE.

  7. How many Enrons? Mark-ups in the stated capital cost of independent power producers' (IPPs') power projects in developing countries

    International Nuclear Information System (INIS)

    Phadke, Amol

    2009-01-01

    I analyze the determinants of the stated capital cost of IPPs' power projects which significantly influences their price of power. I show that IPPs face a strong incentive to overstate their capital cost and argue that effective competition or regulatory scrutiny will limit the extent of the same. I analyze the stated capital costs of combined cycle gas turbine (CCGT) IPP projects in eight developing countries which became operational during 1990-2006 and find that the stated capital cost of projects selected without competitive bidding is 44-56% higher than those selected with competitive bidding, even after controlling for the effect of cost differences among projects. The extent to which the stated capital costs of projects selected without competitive bidding are higher compared those selected with competitive bidding, is a lower bound on the extent to which they are overstated. My results indicate the drawbacks associated with a policy of promoting private sector participation without an adequate focus on improving competition or regulation. (author)

  8. Globalisation and the internationalisation of higher education in sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    Kuzvinetsa Peter Dzvimbo

    2013-01-01

    Full Text Available In a shrinking world, in which a neo-liberal discourse has permeated sub-Saharan African higher education, critical reflection is required to assess the merits and demerits of globalisation. Research, intensive discussion and hearings conducted over a two-year period by the Task Force on Higher Education and Society, convened by the World Bank and United Nations Educational, Scientific, and Cultural Organization (UNESCO for the purpose of exploring the future of higher education in the developing world, led to the conclusion that without more and better higher education, developing countries would find it increasingly difficult to benefit from the global knowledge economy. A decade later, we argue for a radical change in the traditional discourse on globalisation because of the emergence of countries such as China, South Africa, India, and Brazil as global players in the world economy. These emerging global powers, reframe the political and imperial philosophy at the epicentre of globalisation discourse - an economic creed, through their mutual consultation and coordination on significant political issues. Their economic and military capabilities enable them to influence the trade regime and thereby strengthen the voice of the developing world as a whole. In relation to this paper's inquiry, the cooperation of these emerging powers gives the free enfranchised people of the world an opportunity to choose a different path of international relations (internationalisation formed on more liberal lines, as opposed to the neo-liberal economic rationality of globalisation. This paper therefore examines globalisation and internationalisation of higher education in sub-Saharan Africa, a field in which increased knowledge production and distribution open up opportunities for users, institutions and societies. Against a background of chronic economic uncertainty we examine the influence of major international institutions on the direction of higher

  9. Wave-actuated power take-off device for electricity generation

    Energy Technology Data Exchange (ETDEWEB)

    Chertok, Allan

    2013-01-31

    Since 2008, Resolute Marine Energy, Inc. (RME) has been engaged in the development of a rigidly moored shallow-water point absorber wave energy converter, the "3D-WEC". RME anticipated that the 3D-WEC configuration with a fully buoyant point absorber buoy coupled to three power take off (PTO) units by a tripod array of tethers would achieve higher power capture than a more conventional 1-D configuration with a single tether and PTO. The investigation conducted under this program and documented herein addressed the following principal research question regarding RME's power take off (PTO) concept for its 3D-WEC: Is RME's winch-driven generator PTO concept, previously implemented at sub-scale and tested at the Ohmsett wave tank facility, scalable in a cost-effective manner to significant power levels e.g., 10 to 100kW?

  10. Flexible and Cost Efficient Power Consumption using Economic MPC

    DEFF Research Database (Denmark)

    Hovgaard, Tobias Gybel; Larsen, Lars F.S.; Jørgensen, John Bagterp

    2011-01-01

    the formulation of a new cost function for our proposed power management. Hereby the refrigeration system is enabled to contribute with ancillary services to the balancing power market. Since significant amounts of regulating power is needed for a higher penetration of intermittent renewable energy sources...... such as wind turbines this feature is in high demand in a future intelligent power grid (Smart Grid). Our perspective is seen from the refrigeration system but as it is demonstrated the involvement in the balancing market can be economically beneficial for the system itself while delivering crucial services...... that reduces operation costs by utilizing the thermal storage capabilities. In the study we specifically address advantages coming from daily variations in outdoor temperature and electricity prices but other aims such as peak load reduction are also considered. An important contribution of this paper is also...

  11. Strategic wind power trading considering rival wind power production

    DEFF Research Database (Denmark)

    Exizidis, Lazaros; Kazempour, Jalal; Pinson, Pierre

    2016-01-01

    In an electricity market with high share of wind power, it is expected that wind power producers may exercise market power. However, wind producers have to cope with wind’s uncertain nature in order to optimally offer their generation, whereas in a market with more than one wind producers, uncert...... depending on the rival’s wind generation, given that its own expected generation is not high. Finally, as anticipated, expected system cost is higher when both wind power producers are expected to have low wind power generation......In an electricity market with high share of wind power, it is expected that wind power producers may exercise market power. However, wind producers have to cope with wind’s uncertain nature in order to optimally offer their generation, whereas in a market with more than one wind producers......, uncertainty of rival wind power generation should also be considered. Under this context, this paper addresses the impact of rival wind producers on the offering strategy and profits of a pricemaker wind producer. A stochastic day-ahead market setup is considered, which optimizes the day-ahead schedules...

  12. Evaluation of PWR's operating experience. Significant events which influenced French nuclear power program

    International Nuclear Information System (INIS)

    Dupuis, M.C.

    1986-10-01

    This report discusses developments or changes in safety policy (whether statutory or otherwise) and in plant design and operation, which, in many cases, correlate. When considering these events, it is important to bear in mind the standardization policy characterizing the French nuclear power program, and implying central decision-making, both for the safety authorities and the operating utility [fr

  13. Green Power voluntary purchases: Price elasticity and policy analysis

    International Nuclear Information System (INIS)

    Mewton, Ross T.; Cacho, Oscar J.

    2011-01-01

    Green Power schemes offer electricity from renewable energy sources to customers for a higher price than ordinary electricity. This study examines the demand characteristics of Green Power in Australia and policies which could increase its sales. A sample of 250 pooled time series and cross sectional observations was used to estimate a statistically significant elasticity of demand for Green Power with respect to price of -0.96 with a 95% confidence interval of ±68%. The wide variation in market penetration between jurisdictions and between countries for Green Power, and the low awareness of Green Power found by surveys indicate that Green Power sales could be increased by appropriate marketing and government policies. The most cost effective means to increase sales was found to be advertising campaigns although only one Australian example was found, in the state of Victoria in 2005. It was also found that full tax deductibility of the Green Power premium to residential customers, exemption from the Goods and Services Tax and a tax rebate for Green Power are all probably less cost effective for promoting sales than direct government purchase of Green Power, in terms of cost per unit of increased sales.

  14. Green Power voluntary purchases: Price elasticity and policy analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mewton, Ross T., E-mail: rtmewton@hotmail.co [University of New England (Australia); Cacho, Oscar J. [School of Business Economics and Public Policy, School of Economics, University of New England, Armidale, NSW 2351 (Australia)

    2011-01-15

    Green Power schemes offer electricity from renewable energy sources to customers for a higher price than ordinary electricity. This study examines the demand characteristics of Green Power in Australia and policies which could increase its sales. A sample of 250 pooled time series and cross sectional observations was used to estimate a statistically significant elasticity of demand for Green Power with respect to price of -0.96 with a 95% confidence interval of {+-}68%. The wide variation in market penetration between jurisdictions and between countries for Green Power, and the low awareness of Green Power found by surveys indicate that Green Power sales could be increased by appropriate marketing and government policies. The most cost effective means to increase sales was found to be advertising campaigns although only one Australian example was found, in the state of Victoria in 2005. It was also found that full tax deductibility of the Green Power premium to residential customers, exemption from the Goods and Services Tax and a tax rebate for Green Power are all probably less cost effective for promoting sales than direct government purchase of Green Power, in terms of cost per unit of increased sales.

  15. Green Power voluntary purchases. Price elasticity and policy analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mewton, Ross T. [University of New England (Australia); Cacho, Oscar J. [School of Business Economics and Public Policy, School of Economics, University of New England, Armidale, NSW 2351 (Australia)

    2011-01-15

    Green Power schemes offer electricity from renewable energy sources to customers for a higher price than ordinary electricity. This study examines the demand characteristics of Green Power in Australia and policies which could increase its sales. A sample of 250 pooled time series and cross sectional observations was used to estimate a statistically significant elasticity of demand for Green Power with respect to price of -0.96 with a 95% confidence interval of {+-}68%. The wide variation in market penetration between jurisdictions and between countries for Green Power, and the low awareness of Green Power found by surveys indicate that Green Power sales could be increased by appropriate marketing and government policies. The most cost effective means to increase sales was found to be advertising campaigns although only one Australian example was found, in the state of Victoria in 2005. It was also found that full tax deductibility of the Green Power premium to residential customers, exemption from the Goods and Services Tax and a tax rebate for Green Power are all probably less cost effective for promoting sales than direct government purchase of Green Power, in terms of cost per unit of increased sales. (author)

  16. Higher-order tensors in diffusion imaging

    NARCIS (Netherlands)

    Schultz, T.; Fuster, A.; Ghosh, A.; Deriche, R.; Florack, L.M.J.; Lim, L.H.; Westin, C.-F.; Vilanova, A.; Burgeth, B.

    2014-01-01

    Diffusion imaging is a noninvasive tool for probing the microstructure of fibrous nerve and muscle tissue. Higher-order tensors provide a powerful mathematical language to model and analyze the large and complex data that is generated by its modern variants such as High Angular Resolution Diffusion

  17. Serial powering of pixel modules

    CERN Document Server

    Stockmanns, Tobias; Hügging, Fabian Georg; Peric, I; Runólfsson, O; Wermes, Norbert

    2003-01-01

    Modern pixel detectors for the next generation of high-energy collider experiments like LHC use readout electronics in deep sub- micron technology. Chips in this technology need a low supply voltage of 2-2.5 V alongside high current consumption to achieve the desired performance. The high supply current leads to significant voltage drops in the long and low mass supply cables so that voltage fluctuations at the chips are induced, when the supply current changes. This problem scales with the number of modules when connected in parallel to the power supplies. An alternative powering scheme connects several modules in series resulting in a higher supply voltage but a lower current consumption of the chain and therefore a much lower voltage drop in the cables. In addition the amount of cables needed to supply the detector is vastly reduced. The concept and features of serial powering are presented and studies of the implementation of this technology as an alternative for the ATLAS pixel detector are shown. In par...

  18. A systematic experimental investigation of significant parameters affecting model tire hydroplaning

    Science.gov (United States)

    Wray, G. A.; Ehrlich, I. R.

    1973-01-01

    The results of a comprehensive parametric study of model and small pneumatic tires operating on a wet surface are presented. Hydroplaning inception (spin down) and rolling restoration (spin up) are discussed. Conclusions indicate that hydroplaning inception occurs at a speed significantly higher than the rolling restoration speed. Hydroplaning speed increases considerably with tread depth, surface roughness and tire inflation pressure of footprint pressure, and only moderately with increased load. Water film thickness affects spin down speed only slightly. Spin down speed varies inversely as approximately the one-sixth power of film thickness. Empirical equations relating tire inflation pressure, normal load, tire diameter and water film thickness have been generated for various tire tread and surface configurations.

  19. A study of UO2 wafer fuel for very high-power research reactors

    International Nuclear Information System (INIS)

    Hsieh, T.C.; Jankus, V.Z.; Rest, J.; Billone, M.C.

    1983-01-01

    The Reduced Enrichment Research and Test Reactor Program is aimed at reducing fuel enrichment to 2 caramel fuel is one of the most promising new types of reduced-enrichment fuel for use in research reactors with very high power density. Parametric studies have been carried out to determine the maximum specific power attainable without significant fission-gas release for UO 2 wafers ranging from 0.75 to 1.50 mm in thickness. The results indicate that (1) all the fuel designs considered in this study are predicted not to fail under full power operation up to a burnup, of 1.9x10 21 fis/cm 3 ; (2) for all fuel designs, failure is predicted at approximately the same fuel centerline temperature for a given burnup; (3) the thinner the wafer, the wider the margin for fuel specific power between normal operation and increased-power operation leading to fuel failure; (4) increasing the coolant pressure in the reactor core could improve fuel performance by maintaining the fuel at a higher power level without failure for a given burnup; and (5) for a given power level, fuel failure will occur earlier at a higher cladding surface temperature and/or under power-cycling conditions. (author)

  20. Rib fractures and their association With solid organ injury: higher rib fractures have greater significance for solid organ injury screening.

    Science.gov (United States)

    Rostas, Jack W; Lively, Timothy B; Brevard, Sidney B; Simmons, Jon D; Frotan, Mohammad A; Gonzalez, Richard P

    2017-04-01

    The purpose of this study was to identify patients with rib injuries who were at risk for solid organ injury. A retrospective chart review was performed of all blunt trauma patients with rib fractures during the period from July 2007 to July 2012. Data were analyzed for association of rib fractures and solid organ injury. In all, 1,103 rib fracture patients were identified; 142 patients had liver injuries with 109 (77%) associated right rib fractures. Right-sided rib fractures with highest sensitivity for liver injury were middle rib segment (5 to 8) and lower segment (9 to 12) with liver injury sensitivities of 68% and 43%, respectively (P rib fractures. Left middle segment rib fractures and lower segment rib fractures had sensitivities of 80% and 63% for splenic injury, respectively (P Rib fractures higher in the thoracic cage have significant association with solid organ injury. Using rib fractures from middle plus lower segments as indication for abdominal screening will significantly improve rib fracture sensitivity for identification of solid organ injury. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. The Significance of Blackstone's Understanding of Sovereign Immunity for America's Public Institutions of Higher Education.

    Science.gov (United States)

    Snow, Brian A.; Thro, William E.

    2001-01-01

    Asserts that from the perspective of America's public institutions of higher education, Blackstone's greatest legacy is his understanding of sovereign immunity. Explores the similarities between Blackstone's understanding of sovereign immunity and the current jurisprudence of the U.S. Supreme Court. (EV)

  2. Agent-based power sharing scheme for active hybrid power sources

    Science.gov (United States)

    Jiang, Zhenhua

    The active hybridization technique provides an effective approach to combining the best properties of a heterogeneous set of power sources to achieve higher energy density, power density and fuel efficiency. Active hybrid power sources can be used to power hybrid electric vehicles with selected combinations of internal combustion engines, fuel cells, batteries, and/or supercapacitors. They can be deployed in all-electric ships to build a distributed electric power system. They can also be used in a bulk power system to construct an autonomous distributed energy system. An important aspect in designing an active hybrid power source is to find a suitable control strategy that can manage the active power sharing and take advantage of the inherent scalability and robustness benefits of the hybrid system. This paper presents an agent-based power sharing scheme for active hybrid power sources. To demonstrate the effectiveness of the proposed agent-based power sharing scheme, simulation studies are performed for a hybrid power source that can be used in a solar car as the main propulsion power module. Simulation results clearly indicate that the agent-based control framework is effective to coordinate the various energy sources and manage the power/voltage profiles.

  3. Using machine learning to predict wind turbine power output

    International Nuclear Information System (INIS)

    Clifton, A; Kilcher, L; Lundquist, J K; Fleming, P

    2013-01-01

    Wind turbine power output is known to be a strong function of wind speed, but is also affected by turbulence and shear. In this work, new aerostructural simulations of a generic 1.5 MW turbine are used to rank atmospheric influences on power output. Most significant is the hub height wind speed, followed by hub height turbulence intensity and then wind speed shear across the rotor disk. These simulation data are used to train regression trees that predict the turbine response for any combination of wind speed, turbulence intensity, and wind shear that might be expected at a turbine site. For a randomly selected atmospheric condition, the accuracy of the regression tree power predictions is three times higher than that from the traditional power curve methodology. The regression tree method can also be applied to turbine test data and used to predict turbine performance at a new site. No new data are required in comparison to the data that are usually collected for a wind resource assessment. Implementing the method requires turbine manufacturers to create a turbine regression tree model from test site data. Such an approach could significantly reduce bias in power predictions that arise because of the different turbulence and shear at the new site, compared to the test site. (letter)

  4. Critical success factors for BOT electric power projects in China: Thermal power versus wind power

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Zhen-Yu. [School of Business Administration, North China Electric Power University, Beijing 102206 (China); Zuo, Jian; Zillante, George [School of Natural and Built Environments, University of South Australia, Adelaide 5001 (Australia); Wang, Xin-Wei [Shandong Nuclear Power Equipment Manufacturing Co. Ltd, Haiyang, Shandong 265118 (China)

    2010-06-15

    Chinese electric power industry has adopted Build-Operate-Transfer (BOT) approach in a number of projects to alleviate the pressure of sole state-owned investment. The Chinese government has taken enormous efforts to create an environment to facilitate the application of BOT approach in electric power projects. Moreover, the growing attention on the sustainability issues puts the traditional major source of electricity - thermal power project under more strict scrutiny. As a result, various renewable energy projects, particularly the wind power projects have involved private sector funds. Both thermal power and wind power projects via BOT approach have met with a varying degree of success. Therefore, it is imperative to understand the factors contributing towards the success of both types of BOT power projects. Using an extensive literature survey, this paper identifies 31 success factors under 5 categories for Chinese BOT electric power projects. This is followed by a questionnaire survey to exam relative significance of these factors. The results reveal the different levels of significance of success factors for BOT thermal power projects versus wind power projects. Finally, survey results were analyzed to explore the underlying construction and distributions among the identified success factors. This study provides a valuable reference for all involved parties that are interested in developing BOT electric power projects in China. (author)

  5. Flexible dynamic operation of solar-integrated power plant with solvent based post-combustion carbon capture (PCC) process

    International Nuclear Information System (INIS)

    Qadir, Abdul; Sharma, Manish; Parvareh, Forough; Khalilpour, Rajab; Abbas, Ali

    2015-01-01

    Highlights: • Flexible operation of power and PCC plant may significantly increase operational revenue. • Higher optimal carbon capture rates observed with solar thermal energy input. • Solar thermal repowering of the power plant provides highest net revenue. • Constant optimal capture rate observed for one of the flexible operation cases. • Up to 42% higher revenue generation observed between two cases with solar input. - Abstract: This paper examines flexible operation of solvent-based post-combustion carbon capture (PCC) for the reduction of power plant carbon emissions while minimizing revenue loss due to the reduced power plant electricity output. The study is conducted using a model superstructure enveloping three plants; a power plant, a PCC plant and a solar thermal field where the power plant and PCC plant are operated flexibly under the influence of hourly electricity market and weather conditions. Reduced (surrogate) models for the reboiler duty and auxiliary power requirement for the carbon capture plant are generated and applied to simulate and compare four cases, (A) power plant with PCC, (B) power plant with solar assisted PCC, (C) power plant with PCC and solar repowering – variable net electricity output and (D) power plant with PCC and solar repowering – fixed net electricity output. Such analyses are conducted under dynamic conditions including power plant part-load operation while varying the capture rate to optimize the revenue of the power plant. Each case was simulated with a lower carbon price of $25/tonne-CO 2 and a higher price of $50/tonne-CO 2 . The comparison of cases B–D found that optimal revenue generation for case C can be up to 42% higher than that of solar-assisted PCC (case B). Case C is found to be the most profitable with the lowest carbon emissions intensity and is found to exhibit a constant capture rate for both carbon prices. The optimal revenue for case D is slightly lower than case C for the lower carbon

  6. Radiation tolerant power converter controls

    CERN Document Server

    Todd, B; King, Q; Uznanski, S

    2012-01-01

    The Large Hadron Collider (LHC) at the European Organisation for Nuclear Research (CERN) is the world's most powerful particle collider. The LHC has several thousand magnets, both warm and super-conducting, which are supplied with current by power converters. Each converter is controlled by a purpose-built electronic module called a Function Generator Controller (FGC). The FGC allows remote control of the power converter and forms the central part of a closed-loop control system where the power converter voltage is set, based on the converter output current and magnet-circuit characteristics. Some power converters and FGCs are located in areas which are exposed to beam-induced radiation. There are numerous radiation induced effects, some of which lead to a loss of control of the power converter, having a direct impact upon the accelerator's availability. Following the first long shut down (LS1), the LHC will be able to run with higher intensity beams and higher beam energy. This is expected to lead to signifi...

  7. The Role of Cultural Capital in Higher Education Access and Institutional Choice

    Directory of Open Access Journals (Sweden)

    Iva Košutić

    2017-03-01

    Full Text Available This paper aims to explore social inequalities in school achievement and educational decision-making of the final-year students of secondary schools in the City of Zagreb and Zagreb County, Croatia (N = 534. The theoretical framework of the paper was Bourdieu’s theory of cultural and social reproduction (1977a. The main objectives were an analysis of the association between the students’ cultural capital and their school achievement and analyses of the predictive power of the cultural capital theory in the context of educational decisions in the transition to tertiary education. In the analysis of school achievement, sequential multiple regression analysis was used, while in the analyses of educational decisions logistic regression analyses were performed (binary and multinomial logistic regression. The results indicated that cultural capital had statistically significant correlation with school performance. Among the cultural capital indicators, statistically significant predictors of the probability of the intention to enrol into vocational higher education were the material dimension of cultural capital and naturalness of higher education aspirations of students. For the prediction of the probability of intention to enrol in university, significant predictors were embodied cultural capital, the naturalness of higher education aspirations of students, and father’s educational level. The study results on a selected sample of graduates tend to support Bourdieu’s theory of cultural reproduction through education.

  8. Higher-order power harmonics of pulsed electrical stimulation modulates corticospinal contribution of peripheral nerve stimulation.

    Science.gov (United States)

    Chen, Chiun-Fan; Bikson, Marom; Chou, Li-Wei; Shan, Chunlei; Khadka, Niranjan; Chen, Wen-Shiang; Fregni, Felipe

    2017-03-03

    It is well established that electrical-stimulation frequency is crucial to determining the scale of induced neuromodulation, particularly when attempting to modulate corticospinal excitability. However, the modulatory effects of stimulation frequency are not only determined by its absolute value but also by other parameters such as power at harmonics. The stimulus pulse shape further influences parameters such as excitation threshold and fiber selectivity. The explicit role of the power in these harmonics in determining the outcome of stimulation has not previously been analyzed. In this study, we adopted an animal model of peripheral electrical stimulation that includes an amplitude-adapted pulse train which induces force enhancements with a corticospinal contribution. We report that the electrical-stimulation-induced force enhancements were correlated with the amplitude of stimulation power harmonics during the amplitude-adapted pulse train. In an exploratory analysis, different levels of correlation were observed between force enhancement and power harmonics of 20-80 Hz (r = 0.4247, p = 0.0243), 100-180 Hz (r = 0.5894, p = 0.0001), 200-280 Hz (r = 0.7002, p harmonics. This is a pilot, but important first demonstration that power at high order harmonics in the frequency spectrum of electrical stimulation pulses may contribute to neuromodulation, thus warrant explicit attention in therapy design and analysis.

  9. Reactive Power Pricing Model Considering the Randomness of Wind Power Output

    Science.gov (United States)

    Dai, Zhong; Wu, Zhou

    2018-01-01

    With the increase of wind power capacity integrated into grid, the influence of the randomness of wind power output on the reactive power distribution of grid is gradually highlighted. Meanwhile, the power market reform puts forward higher requirements for reasonable pricing of reactive power service. Based on it, the article combined the optimal power flow model considering wind power randomness with integrated cost allocation method to price reactive power. Meanwhile, considering the advantages and disadvantages of the present cost allocation method and marginal cost pricing, an integrated cost allocation method based on optimal power flow tracing is proposed. The model realized the optimal power flow distribution of reactive power with the minimal integrated cost and wind power integration, under the premise of guaranteeing the balance of reactive power pricing. Finally, through the analysis of multi-scenario calculation examples and the stochastic simulation of wind power outputs, the article compared the results of the model pricing and the marginal cost pricing, which proved that the model is accurate and effective.

  10. Wind power and market power in competitive markets

    International Nuclear Information System (INIS)

    Twomey, Paul; Neuhoff, Karsten

    2010-01-01

    Average market prices for intermittent generation technologies are lower than for conventional generation. This has a technical reason but can be exaggerated in the presence of market power. When there is much wind smaller amounts of conventional generation technologies are required, and prices are lower, while at times of little wind prices are higher. This effect reflects the value of different generation technologies to the system. But under conditions of market power, conventional generators with market power can further depress the prices if they have to buy back energy at times of large wind output and can increase prices if they have to sell additional power at times of little wind output. This greatly exaggerates the effect. Forward contracting does not reduce the effect. An important consequence is that allowing market power profit margins as a support mechanism for generation capacity investment is not a technologically neutral policy.

  11. Power Generation Using Mechanical Wave Energy Converter

    Directory of Open Access Journals (Sweden)

    Srinivasan Chandrasekaran

    2012-03-01

    Full Text Available Ocean wave energy plays a significant role in meeting the growing demand of electric power. Economic, environmental, and technical advantages of wave energy set it apart from other renewable energy resources. Present study describes a newly proposed Mechanical Wave Energy Converter (MEWC that is employed to harness heave motion of floating buoy to generate power. Focus is on the conceptual development of the device, illustrating details of component level analysis. Employed methodology has many advantages such as i simple and easy fabrication; ii easy to control the operations during rough weather; and iii low failure rate during normal sea conditions. Experimental investigations carried out on the scaled model of MWEC show better performance and its capability to generate power at higher efficiency in regular wave fields. Design Failure Mode and Effect Analysis (FMEA shows rare failure rates for all components except the floating buoy.

  12. Enhanced Wireless Power Transmission Using Strong Paramagnetic Response.

    Science.gov (United States)

    Ahn, Dukju; Kiani, Mehdi; Ghovanloo, Maysam

    2014-03-01

    A method of quasi-static magnetic resonant coupling has been presented for improving the power transmission efficiency (PTE) in near-field wireless power transmission, which improves upon the state of the art. The traditional source resonator on the transmitter side is equipped with an additional resonator with a resonance frequency that is tuned substantially higher than the magnetic field excitation frequency. This additional resonator enhances the magnetic dipole moment and the effective permeability of the power transmitter, owing to a phenomenon known as the strong paramagnetic response. Both theoretical calculations and experimental results show increased PTE due to amplification of the effective permeability. In measurements, the PTE was improved from 57.8% to 64.2% at the nominal distance of 15 cm when the effective permeability was 2.6. The power delivered to load was also improved significantly, with the same 10 V excitation voltage, from 0.38 to 5.26 W.

  13. Maximum power point tracking

    International Nuclear Information System (INIS)

    Enslin, J.H.R.

    1990-01-01

    A well engineered renewable remote energy system, utilizing the principal of Maximum Power Point Tracking can be m ore cost effective, has a higher reliability and can improve the quality of life in remote areas. This paper reports that a high-efficient power electronic converter, for converting the output voltage of a solar panel, or wind generator, to the required DC battery bus voltage has been realized. The converter is controlled to track the maximum power point of the input source under varying input and output parameters. Maximum power point tracking for relative small systems is achieved by maximization of the output current in a battery charging regulator, using an optimized hill-climbing, inexpensive microprocessor based algorithm. Through practical field measurements it is shown that a minimum input source saving of 15% on 3-5 kWh/day systems can easily be achieved. A total cost saving of at least 10-15% on the capital cost of these systems are achievable for relative small rating Remote Area Power Supply systems. The advantages at larger temperature variations and larger power rated systems are much higher. Other advantages include optimal sizing and system monitor and control

  14. Rest Interval Required for Power Training With Power Load in the Bench Press Throw Exercise.

    Science.gov (United States)

    Hernández Davó, Jose L; Solana, Rafael Sabido; Sarabia Marín, Jose M; Fernández Fernández, Jaime; Moya Ramón, Manuel

    2016-05-01

    This study aimed to test the influence of various rest interval (RI) durations used between sets on power output performance and physiological and perceptual variables during a strength training session using 40% of the 1 repetition maximum (1RM) in the bench press throw exercise. Thirty-one college students (18 males and 13 females) took part in the study. The experimental protocol consists of 5 sets of 8 repetitions of the bench press throw exercise with a load representing 40% of 1RM. Subjects performed the experimental protocol on 3 different occasions, differing by the RI between sets (1, 2, or 3 minutes). During the sessions, power data (mean power and peak power), physiological (lactate concentration [La]) and perceptual (rating of perceived exertion) variables were measured. In addition, delayed onset muscular soreness was reported 24 and 48 hours after the training session. One-way repeated-measures analysis of variance showed that 1-minute RI entailed higher power decreases and greater increases in values of physiological and perceptual variables compared with both 2- and 3-minute RIs. Nevertheless, no differences were found between 2- and 3-minute RIs. Therefore, this study showed that, when training with 40% of 1RM in the bench press throw exercise, a 2-minute RI between sets can be enough to avoid significant decreases in power output. Consequently, training sessions' duration could be reduced without causing excessive fatigue, allowing additional time to focus on other conditioning priorities.

  15. Higher-order gravity in higher dimensions: geometrical origins of four-dimensional cosmology?

    Energy Technology Data Exchange (ETDEWEB)

    Troisi, Antonio [Universita degli Studi di Salerno, Dipartimento di Fisica ' ' E.R. Caianiello' ' , Salerno (Italy)

    2017-03-15

    Determining the cosmological field equations is still very much debated and led to a wide discussion around different theoretical proposals. A suitable conceptual scheme could be represented by gravity models that naturally generalize Einstein theory like higher-order gravity theories and higher-dimensional ones. Both of these two different approaches allow one to define, at the effective level, Einstein field equations equipped with source-like energy-momentum tensors of geometrical origin. In this paper, the possibility is discussed to develop a five-dimensional fourth-order gravity model whose lower-dimensional reduction could provide an interpretation of cosmological four-dimensional matter-energy components. We describe the basic concepts of the model, the complete field equations formalism and the 5-D to 4-D reduction procedure. Five-dimensional f(R) field equations turn out to be equivalent, on the four-dimensional hypersurfaces orthogonal to the extra coordinate, to an Einstein-like cosmological model with three matter-energy tensors related with higher derivative and higher-dimensional counter-terms. By considering the gravity model with f(R) = f{sub 0}R{sup n} the possibility is investigated to obtain five-dimensional power law solutions. The effective four-dimensional picture and the behaviour of the geometrically induced sources are finally outlined in correspondence to simple cases of such higher-dimensional solutions. (orig.)

  16. Nuclear Power Prospects

    International Nuclear Information System (INIS)

    Cintra do Prado, L.

    1966-01-01

    The present trend is to construct larger plants: the average power of the plants under construction at present, including prototypes, is 300 MW(e), i.e. three times higher than in the case of plants already in operation. Examples of new large-scale plants ares (a) Wylfa, Anglesey, United Kingdom - scheduled power of 1180 MW(e) (800 MW to be installed by 1967), to be completed in 1968; (b) ''Dungeness B'', United Kingdom - scheduled power of 1200 MW(e); (c) second unit for United States Dresden power plant - scheduled power of 715 MW(e) minimum to almost 800 MW(e). Nuclear plants on the whole serve the same purpose as conventional thermal plants

  17. Comparative Analysis of Power Plant Options for Enhanced Geothermal Systems (EGS

    Directory of Open Access Journals (Sweden)

    Mengying Li

    2014-12-01

    Full Text Available Enhanced geothermal systems (EGS extract heat from underground hot dry rock (HDR by first fracturing the HDR and then circulating a geofluid (typically water into it and bringing the heated geofluid to a power plant to generate electricity. This study focuses on analysis, examination, and comparison of leading geothermal power plant configurations with a geofluid temperature from 200 to 800 °C, and also analyzes the embodied energy of EGS surface power plants. The power generation analysis is focused on flash type cycles for using subcritical geofluid (<374 °C and expansion type cycles for using supercritical geofluid (>374 °C. Key findings of this study include: (i double-flash plants have 24.3%–29.0% higher geofluid effectiveness than single-flash ones, and 3%–10% lower specific embodied energy; (ii the expansion type plants have geofluid effectiveness > 750 kJ/kg, significantly higher than flash type plants (geofluid effectiveness < 300 kJ/kg and the specific embodied energy is lower; (iii to increase the turbine outlet vapor fraction from 0.75 to 0.90, we include superheating by geofluid but that reduces the geofluid effectiveness by 28.3%; (iv for geofluid temperatures above 650 °C, double-expansion plants have a 2% higher geofluid effectiveness and 5%–8% lower specific embodied energy than single-expansion ones.

  18. Muscle Power during Standing and Seated Trunk Rotations with Different Weights

    Directory of Open Access Journals (Sweden)

    Erika Zemková

    2017-10-01

    Full Text Available This study compares peak and mean power during standing and seated trunk rotations with different weights. Twenty seven fit men completed four trials of trunk rotations in both standing and seated positions with a bar weight of 5.5, 10.5, 15.5, and 20 kg placed on the shoulders. The FiTRO Torso Premium was used to monitor basic biomechanical parameters throughout the movement. Results showed significantly higher peak power during standing than seated trunk rotations at weights of 20 kg (274.4±63.5 vs. 206.4±54.6 W, p=0.004, 15.5 kg (371.2±93.9 vs. 313.5±72.3 W, p=0.007, and 10.5 kg (336.9±77.8 vs. 286.3±66.0 W, p=0.009 but not at 5.5 kg (191.6±46.2 vs. 166.0±37.0 W, p=0.061. Similarly, mean power in the acceleration phase of trunk rotations was significantly higher when performed in standing than seated position at weights of 20 kg (143.2±32.1 vs. 101.9±23.7 W, p=0.008, 15.5 kg (185.1±42.3 vs. 150.4±36.5 W, p=0.019, and 10.5 kg (169.8±40.7 vs. 139.7±31.6 W, p=0.024 but not at 5.5 kg (107.4±29.4 vs. 86.5±21.1 W, p=0.111. Furthermore, peak and mean power during standing trunk rotations significantly correlated with values achieved in the seated position at the weight of 5.5 kg (r=0.684, p=0.027; r=0.676, p=0.033 but not at 10.5 kg (r=0.589, p=0.089; r=0.552, p=0.143, 15.5 kg (r=0.493, p=0.243; r=0.436, p=0.298, and 20 kg (r=0.357, p=0.361; r=0.333, p=0.417. In conclusion, power production is greater during standing as compared to seated trunk rotations, with more pronounced differences at higher weights. This fact has to be taken into account when training and testing the trunk rotational power.

  19. Impacts of supersymmetric higher derivative terms on inflation models in supergravity

    International Nuclear Information System (INIS)

    Aoki, Shuntaro; Yamada, Yusuke

    2015-01-01

    We show the effects of supersymmetric higher derivative terms on inflation models in supergravity. The results show that such terms generically modify the effective kinetic coefficient of the inflaton during inflation if the cut off scale of the higher derivative operators is sufficiently small. In such a case, the η-problem in supergravity does not occur, and we find that the effective potential of the inflaton generically becomes a power type potential with a power smaller than two

  20. CRISS power spectral density

    International Nuclear Information System (INIS)

    Vaeth, W.

    1979-04-01

    The correlation of signal components at different frequencies like higher harmonics cannot be detected by a normal power spectral density measurement, since this technique correlates only components at the same frequency. This paper describes a special method for measuring the correlation of two signal components at different frequencies: the CRISS power spectral density. From this new function in frequency analysis, the correlation of two components can be determined quantitatively either they stem from one signal or from two diverse signals. The principle of the method, suitable for the higher harmonics of a signal as well as for any other frequency combinations is shown for the digital frequency analysis technique. Two examples of CRISS power spectral densities demonstrates the operation of the new method. (orig.) [de

  1. Higher Efficiency HVAC Motors

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, Charles Joseph [QM Power, Inc., Kansas City, MO (United States)

    2018-02-13

    failure prone capacitors from the power stage. Q-Sync’s simpler electronics also result in higher efficiency because it eliminates the power required by the PCB to perform the obviated power conversions and PWM processes after line synchronous operating speed is reached in the first 5 seconds of operation, after which the PWM circuits drop out and a much less energy intensive “pass through” circuit takes over, allowing the grid-supplied AC power to sustain the motor’s ongoing operation.

  2. Efficiency improvement of nuclear power plant operation: the significant role of advanced nuclear fuel technologies

    International Nuclear Information System (INIS)

    Velde Van de, A.; Burtak, F.

    2001-01-01

    Due to the increased liberalisation of the power markets, nuclear power generation is being exposed to high cost reduction pressure. In this paper we highlight the role of advanced nuclear fuel technologies to reduce the fuel cycle costs and therefore increase the efficiency of nuclear power plant operation. The key factor is a more efficient utilisation of the fuel and present developments at Siemens are consequently directed at (i) further increase of batch average burnup, (ii) improvement of fuel reliability, (iii) enlargement of fuel operation margins and (iv) improvement of methods for fuel design and core analysis. As a result, the nuclear fuel cycle costs for a typical LWR have been reduced during the past decades by about US$ 35 million per year. The estimated impact of further burnup increases on the fuel cycle costs is expected to be an additional saving of US$10 - 15 million per year. Due to the fact that the fuel will operate closer to design limits, a careful approach is required when introducing advanced fuel features in reload quantities. Trust and co-operation between the fuel vendors and the utilities is a prerequisite for the common success. (authors)

  3. Applications of power beaming from space-based nuclear power stations

    International Nuclear Information System (INIS)

    Powell, J.R.; Botts, T.E.; Hertzberg, A.

    1981-01-01

    Power beaming from space-based reactor systems is examined using an advanced compact, lightweight Rotating Bed Reactor (RBR). Closed Brayton power conversion efficiencies in the range of 30 to 40% can be achieved with turbines, with reactor exit temperatures on the order of 2000 0 K and a liquid drop radiator to reject heat at temperatures of approx. 500 0 K. Higher RBR coolant temperatures (up to approx. 3000 0 K) are possible, but gains in power conversion efficiency are minimal, due to lower expander efficiency (e.g., a MHD generator). Two power beaming applications are examined - laser beaming to airplanes and microwave beaming to fixed ground receivers. Use of the RBR greatly reduces system weight and cost, as compared to solar power sources. Payback times are a few years at present prices for power and airplane fuel

  4. Power plant perspectives for sugarcane mills

    International Nuclear Information System (INIS)

    Bocci, E.; Di Carlo, A.; Marcelo, D.

    2009-01-01

    Biomass, integral to life, is one of the main energy sources that modern technologies could widely develop, overcoming inefficient and pollutant uses. The sugarcane bagasse is one of the more abundant biomass. Moreover, the fluctuating sugar and energy prices force the sugarcane companies to implement improved power plants. Thanks to a multiyear collaboration between University of Rome and University of Piura and Chiclayo, this paper investigates, starting from the real data of an old sugarcane plant, the energy efficiency of the plant. Furthermore, it explores possible improvements as higher temperature and pressure Rankine cycles and innovative configurations based on gasifier plus hot gas conditioning and gas turbine or molten carbonate fuel cells. Even if the process of sugar extraction from sugarcane and the relative Rankine cycles power plants are well documented in literature, this paper shows that innovative power plant configurations can increase the bagasse-based cogeneration potential. Sugarcane companies can become electricity producers, having convenience in the use of sugarcane leaves and trash (when it is feasible). The worldwide implementation of advanced power plants, answering to a market competition, will improve significantly the renewable electricity produced, reducing CO 2 emissions, and increasing economic and social benefits.

  5. Power Electronics Converters for Wind Turbine Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Liserre, Marco; Ma, Ke

    2012-01-01

    The steady growth of installed wind power together with the upscaling of the single wind turbine power capability has pushed the research and development of power converters toward full-scale power conversion, lowered cost pr kW, increased power density, and also the need for higher reliability. ...

  6. Fireside corrosion of superheaters/reheaters in advanced power plants

    Energy Technology Data Exchange (ETDEWEB)

    Syed, A.U.; Simms, N.J.; Oakey, J.E. [Cranfield Univ. (United Kingdom). Energy Technology Centre

    2010-07-01

    The generation of increasing amounts of electricity while simultaneously reducing environmental emissions (CO{sub 2}, SO{sub 2}, NO{sub x} particles, etc) has become a goal for the power industry worldwide. Co-firing biomass and coal in new advanced pulverised fuel power plants is one route to address this issue, since biomass is regarded as a CO{sub 2} neutral fuel (i.e. CO{sub 2} uptake during its growth equals the CO{sub 2} emissions produced during its combustion) and such new advanced power plants operate at higher efficiencies than current plants as a result of using steam systems with high temperatures and pressures. However, co-firing has the potential to cause significant operational challenges for such power plants as amongst other issues, it will significantly change the chemistry of the deposits on the heat exchanger surfaces and the surrounding gas compositions. As a result these critical components can experience higher corrosion rates, and so shorter lives, causing increased operational costs, unless the most appropriate materials are selected for their construction. This paper reports the results of a series of 1000 hour laboratory corrosion tests that have been carried out in controlled atmosphere furnaces, to assess the effect of biomass/coal co-firing on the fireside corrosion of superheaters/reheaters. The materials used for the tests were one ferritic alloy (T92), two austenitic alloys (347HFG and HR3C) and one nickel based alloy (alloy 625). Temperatures of 600 and 650 C were used to represent the metal temperatures in advanced power plants. During these exposures, traditional mass change data were recorded as the samples were recoated with the simulated deposits. After these exposures, cross-sections through samples were prepared using standard metallographic techniques and then analysed using SEM/EDX. Pre-exposure micrometer and post-exposure image analyser measurements were used so that the metal wastage could be calculated. These data are

  7. Phasing in wind-power in Norway: Network congestion and crowding-out of hydropower

    International Nuclear Information System (INIS)

    Forsund, Finn R.; Singh, Balbir; Jensen, Trond; Larsen, Cato

    2008-01-01

    The objective of this paper is to investigate the effects on utilisation of existing hydropower in a region of investing in significant wind-power in the region within the present network. Policy simulations are conducted using a dynamic system-wide model that is calibrated to reflect the structure of the Nordic power market. This model is the one used by the Norwegian electricity regulator and large hydropower companies in Norway for scheduling of hydro and market analyses. Simulations are carried out for different inflow situations based on past observations going back 60 years. Introduction of wind-power leads to significant increase in network congestion in the region, lower hydropower production, higher level of storage, increased spillage of water, and considerably lower price level in the local region in question

  8. 'Nuclearelectrica' and restructuring the electric power sector in Romania

    International Nuclear Information System (INIS)

    Metes, Mircea

    2001-01-01

    The paper presents the first steps of the energy market development in Romania and the impact of this process on 'Nuclearelectrica' company which operates the Cernavoda NPP. The main directions of the power sector liberalization in the European Union are being implemented in Romania. 'Nuclearelectrica' attempts to comply with both economic and safety requirements for nuclear plant operation. So far, the evolution of power market proved the competitiveness of Cernavoda Unit 1 with the existing power producers in Romania. It is stressed that although the 'Hydroelectrica' company sells the MWh at a lower price it cannot cope with top demands higher than 2400 MW. Economical aspects are analyzed and the conclusion is drawn that the situation of 'Nuclearelectrica' company will be significantly changed after the commissioning of Cernavoda Unit 2. (author)

  9. Atmospheric freeze drying assisted by power ultrasound

    International Nuclear Information System (INIS)

    Santacatalina, J V; Cárcel, J A; Garcia-Perez, J V; Mulet, A; Simal, S

    2012-01-01

    Atmospheric freeze drying (AFD) is considered an alternative to vacuum freeze drying to keep the quality of fresh product. AFD allows continuous drying reducing fix and operating costs, but presents, as main disadvantage, a long drying time required. The application of power ultrasound (US) can accelerate AFD process. The main objective of the present study was to evaluate the application of power ultrasound to improve atmospheric freeze drying of carrot. For that purpose, AFD experiments were carried out with carrot cubes (10 mm side) at constant air velocity (2 ms −1 ), temperature (−10°C) and relative humidity (10%) with (20.5 kWm −3 ,USAFD) and without (AFD) ultrasonic application. A diffusion model was used in order to quantify the influence of US in drying kinetics. To evaluate the quality of dry products, rehydration capacity and textural properties were determined. The US application during AFD of carrot involved the increase of drying rate. The effective moisture diffusivity identified in USAFD was 73% higher than in AFD experiments. On the other hand, the rehydration capacity was higher in USAFD than in AFD and the hardness of dried samples did not show significant (p<0.05) differences. Therefore, US application during AFD significantly (p<0.05) sped-up the drying process preserving the quality properties of the dry product.

  10. Power marketing

    International Nuclear Information System (INIS)

    Sioshansi, F.P.; Altman, A.M.

    1998-01-01

    One of the most significant developments in the US electric power industry in recent years has been the phenomenal growth of power marketing. What was barely a blimp on the radar screen in 1992 has turned out to be a jumbo jet. This article explains what is power marketing who are power marketers, what role play these players and what will be their longer-term impact on the traditional industry [it

  11. Evaluation of personality features of nuclear power plant operators: investigation with Minnesota Multiphasic Personality Inventory

    International Nuclear Information System (INIS)

    Sun Yiling; Liu Yulong; Li Yuan; Bian Huahui; Bi Jinling; Qiu Mengyue; Liu Chunfeng

    2011-01-01

    Objective: To explore the personality features of nuclear power plant operators and the influencing factors thereof. Methods: Minnesota Multiphasic Personality Inventory was used to examine the personality features of 136 nuclear power plant operators randomly selected from 2 cooperative units, all males. The results were compared with the nationwide norms and subsequently an inter-block contrast analysis was carried out. Results: Obvious difference was observed in the final scores between the nuclear power plant operators and nationwide norms. The former got higher scores on hysteria (t=3.05, P<0.05), and lower scores on hypochondriasis, depression, morbid personality, masculinity-femininity, paranoia, psychasthenia, schizophrenia, hypomania, and social introversion(t=7.47, 7.47, 7.31, 2.23, 15.09, 16.15, 19.28, 7.88, 11.10, P<0.05). The scores on hypochondriasis, depression, schizophrenia, and social introversion of those with the length of services over 3 years were all significantly higher than those of with the length of services less than 3 years (t=3.25, 2.51, 2.76, 3.00, P<0.05). The scores on hypochondriasis, depression, psychopathicdeviate, and social introversion of the operators aged over 30 were all significantly higher than those of the operators aged below 30 (t=2.36, 2.35, 2.01, 2.54, P<0.05). Conclusions: The psychological quality of the nuclear power plant operators is superior to that of the general population. (authors)

  12. High Power Modulator/regulators for neutral beam sources

    International Nuclear Information System (INIS)

    Lawson, J.Q.; Deitz, A.

    1975-01-01

    PPPL has recently completed two new Modulator/Regulators for neutral injection sources used on the ATC machine and is constructing four new ones for use with sources on the PLT machine. The ATC modulator uses the well proven 4CX35,000C tetrode as the main switch tube, while the PLT modulators will be using the new but significantly higher powered X-2170 tetrodes. Some interesting circuit and manufacturing techniques are discussed

  13. Pyrolysis of tyre powder using microwave thermogravimetric analysis: Effect of microwave power.

    Science.gov (United States)

    Song, Zhanlong; Yang, Yaqing; Zhou, Long; Zhao, Xiqiang; Wang, Wenlong; Mao, Yanpeng; Ma, Chunyuan

    2017-02-01

    The pyrolytic characteristics of tyre powder treated under different microwave powers (300, 500, and 700 W) were studied via microwave thermogravimetric analysis. The product yields at different power levels were studied, along with comparative analysis of microwave pyrolysis and conventional pyrolysis. The feedstock underwent preheating, intense pyrolysis, and final pyrolysis in sequence. The main and secondary weight loss peaks observed during the intense pyrolysis stage were attributed to the decomposition of natural rubbers and synthetic rubbers, respectively. The total mass loss rates, bulk temperatures, and maximum temperatures were distinctively higher at higher powers. However, the maximum mass loss rate (0.005 s -1 ), the highest yields of liquid product (53%), and the minimum yields of residual solid samples (43.83%) were obtained at 500 W. Compared with conventional pyrolysis, microwave pyrolysis exhibited significantly different behaviour with faster reaction rates, which can decrease the decomposition temperatures of both natural and synthetic rubber by approximately 110 °C-140 °C.

  14. Dictionary Pruning with Visual Word Significance for Medical Image Retrieval.

    Science.gov (United States)

    Zhang, Fan; Song, Yang; Cai, Weidong; Hauptmann, Alexander G; Liu, Sidong; Pujol, Sonia; Kikinis, Ron; Fulham, Michael J; Feng, David Dagan; Chen, Mei

    2016-02-12

    Content-based medical image retrieval (CBMIR) is an active research area for disease diagnosis and treatment but it can be problematic given the small visual variations between anatomical structures. We propose a retrieval method based on a bag-of-visual-words (BoVW) to identify discriminative characteristics between different medical images with Pruned Dictionary based on Latent Semantic Topic description. We refer to this as the PD-LST retrieval. Our method has two main components. First, we calculate a topic-word significance value for each visual word given a certain latent topic to evaluate how the word is connected to this latent topic. The latent topics are learnt, based on the relationship between the images and words, and are employed to bridge the gap between low-level visual features and high-level semantics. These latent topics describe the images and words semantically and can thus facilitate more meaningful comparisons between the words. Second, we compute an overall-word significance value to evaluate the significance of a visual word within the entire dictionary. We designed an iterative ranking method to measure overall-word significance by considering the relationship between all latent topics and words. The words with higher values are considered meaningful with more significant discriminative power in differentiating medical images. We evaluated our method on two public medical imaging datasets and it showed improved retrieval accuracy and efficiency.

  15. Power monitors: A framework for system-level power estimation using heterogeneous power models

    NARCIS (Netherlands)

    Bansal, N.; Lahiri, K.; Raghunathan, A.; Chakradhar, S.T.

    2005-01-01

    Paper analysis early in the design cycle is critical for the design of low-power systems. With the move to system-level specifications and design methodologies, there has been significant research interest in system-level power estimation. However, as demonstrated in this paper, the addition of

  16. The effect of power change on the PCI failure threshold

    Energy Technology Data Exchange (ETDEWEB)

    Sipush, P J; Kaiser, R S [Westinghouse Nuclear Fuel Division, Pittsburg, PA (United States)

    1983-06-01

    Investigations of the PCI mechanism have led to the conclusion that the failure threshold is best defined by the power change ({delta}P) during the ramp, rather than the final power achieved at the end of the ramp. The data base studied was comprehensive and includes a wide variety of water reactor systems and fuel designs. It has also been found that operating parameters have a more significant effect on failure susceptibility than fuel rod design variables. The most significant operating variable affecting the failure threshold was found to be the base irradiation history, indicating that fission product release and migration prior to the ramp (during base irradiation) is an important consideration. It can be shown that fuel irradiated at relatively higher linear heat ratings ends to fail at lower {delta}P. This effect has also been independently verified by statistical analyses which will also be discussed. Industry out-of-pile internal gas pressurization tests with irradiated tubing in the absence of simulated fission product species and at low stress levels, also tends to indicate the importance of the prior irradiation history on PCI performance. Other parameters that affect the power ramping performance are the initial ramping power and the pellet power distribution which is a function of fuel enrichment and burnup. (author)

  17. The Spatial Power Motivation Scale: a semi-implicit measure of situational power motivation.

    Science.gov (United States)

    Schoel, Christiane; Zimmer, Katharina; Stahlberg, Dagmar

    2015-01-01

    We introduce a new nonverbal and unobtrusive measure to assess power motive activation, the Spatial Power Motivation Scale (SPMS). The unique features of this instrument are that it is (a) very simple and economical, (b) reliable and valid, and (c) sensitive to situational changes. Study 1 demonstrates the instrument's convergent and discriminant validity with explicit measures. Study 2 demonstrates the instrument's responsiveness to situational power motive salience: anticipating and winning competition versus losing competition and watching television. Studies 3 and 4 demonstrate that thoughts of competition result in higher power motivation specifically for individuals with a high dispositional power motive.

  18. Sustainable nuclear power - the human dimension

    International Nuclear Information System (INIS)

    Peddicorda, K.L.; Poston, John W. Sr.; Sayko, Tami Davis; Porter, Jay; Reece, W. Dan; Earl, Beth; Ostroskaya, Natela; Lagoudas, Magdalini; Crenshaw, John; Jump, Will; Fenner, Clarence; Lowery, Kirby; Sieben, Steve; Jones, Larry; Ridge, Douglas; Robertson, Dale; Hyde, Carliss; Kuruvilla, John; Kinnison, Wayne; Harris, Kendall; Aghara, Sukesh; Pezold, Frank; Bird, Bobby; Rice, Bill

    2008-01-01

    The availability of a well-prepared workforce is fundamental to the increased use of nuclear energy. Significant numbers of new employees will be needed not only for the new plants, but to replace retirees at the existing plants. In addition, a wide variety of disciplines and levels of educational backgrounds are needed. The Nuclear Power Institute is a partnership of industry, higher education, secondary and middle schools, state government and civic and community leadership that has come together to meet the challenge of attracting and preparing the nuclear workforce. (authors)

  19. Effectiveness of Traditional Strength vs. Power Training on Muscle Strength, Power and Speed with Youth: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Behm, David G.; Young, James D.; Whitten, Joseph H. D.; Reid, Jonathan C.; Quigley, Patrick J.; Low, Jonathan; Li, Yimeng; Lima, Camila D.; Hodgson, Daniel D.; Chaouachi, Anis; Prieske, Olaf; Granacher, Urs

    2017-01-01

    Numerous national associations and multiple reviews have documented the safety and efficacy of strength training for children and adolescents. The literature highlights the significant training-induced increases in strength associated with youth strength training. However, the effectiveness of youth strength training programs to improve power measures is not as clear. This discrepancy may be related to training and testing specificity. Most prior youth strength training programs emphasized lower intensity resistance with relatively slow movements. Since power activities typically involve higher intensity, explosive-like contractions with higher angular velocities (e.g., plyometrics), there is a conflict between the training medium and testing measures. This meta-analysis compared strength (e.g., training with resistance or body mass) and power training programs (e.g., plyometric training) on proxies of muscle strength, power, and speed. A systematic literature search using a Boolean Search Strategy was conducted in the electronic databases PubMed, SPORT Discus, Web of Science, and Google Scholar and revealed 652 hits. After perusal of title, abstract, and full text, 107 studies were eligible for inclusion in this systematic review and meta-analysis. The meta-analysis showed small to moderate magnitude changes for training specificity with jump measures. In other words, power training was more effective than strength training for improving youth jump height. For sprint measures, strength training was more effective than power training with youth. Furthermore, strength training exhibited consistently large magnitude changes to lower body strength measures, which contrasted with the generally trivial, small and moderate magnitude training improvements of power training upon lower body strength, sprint and jump measures, respectively. Maturity related inadequacies in eccentric strength and balance might influence the lack of training specificity with the unilateral

  20. Effectiveness of Traditional Strength vs. Power Training on Muscle Strength, Power and Speed with Youth: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    David G. Behm

    2017-06-01

    Full Text Available Numerous national associations and multiple reviews have documented the safety and efficacy of strength training for children and adolescents. The literature highlights the significant training-induced increases in strength associated with youth strength training. However, the effectiveness of youth strength training programs to improve power measures is not as clear. This discrepancy may be related to training and testing specificity. Most prior youth strength training programs emphasized lower intensity resistance with relatively slow movements. Since power activities typically involve higher intensity, explosive-like contractions with higher angular velocities (e.g., plyometrics, there is a conflict between the training medium and testing measures. This meta-analysis compared strength (e.g., training with resistance or body mass and power training programs (e.g., plyometric training on proxies of muscle strength, power, and speed. A systematic literature search using a Boolean Search Strategy was conducted in the electronic databases PubMed, SPORT Discus, Web of Science, and Google Scholar and revealed 652 hits. After perusal of title, abstract, and full text, 107 studies were eligible for inclusion in this systematic review and meta-analysis. The meta-analysis showed small to moderate magnitude changes for training specificity with jump measures. In other words, power training was more effective than strength training for improving youth jump height. For sprint measures, strength training was more effective than power training with youth. Furthermore, strength training exhibited consistently large magnitude changes to lower body strength measures, which contrasted with the generally trivial, small and moderate magnitude training improvements of power training upon lower body strength, sprint and jump measures, respectively. Maturity related inadequacies in eccentric strength and balance might influence the lack of training specificity with

  1. 363 Evaluating Students' Plagiarism in Higher Education Institutions ...

    African Journals Online (AJOL)

    Nekky Umera

    As one of the major players in knowledge economy, higher education institutions have ..... Knowledge, they say is power and knowledge is acquired by authentic learning. ... Harris, R. (2004) Anti-Plagiarism Strategies for Research Papers.

  2. Nonlocal higher order evolution equations

    KAUST Repository

    Rossi, Julio D.

    2010-06-01

    In this article, we study the asymptotic behaviour of solutions to the nonlocal operator ut(x, t)1/4(-1)n-1 (J*Id -1)n (u(x, t)), x ∈ ℝN, which is the nonlocal analogous to the higher order local evolution equation vt(-1)n-1(Δ)nv. We prove that the solutions of the nonlocal problem converge to the solution of the higher order problem with the right-hand side given by powers of the Laplacian when the kernel J is rescaled in an appropriate way. Moreover, we prove that solutions to both equations have the same asymptotic decay rate as t goes to infinity. © 2010 Taylor & Francis.

  3. Development and application of a methodology for the analysis of significant human related event trends in nuclear power plants

    International Nuclear Information System (INIS)

    Cho, H.Y.

    1981-01-01

    A methodology is developed to identify and flag significant trends related to the safety and availability of U.S. commercial nuclear power plants. The development is intended to aid in reducing likelihood of human errors. To assure that the methodology can be easily adapted to various types of classification schemes of operation data, a data bank classified by the Transient Analysis Classification and Evaluation (TRACE) scheme is selected for the methodology. The significance criteria for human-initiated events affecting the systems and for events caused by human deficiencies were developed. Clustering analysis was used to verify the learning trend in multidimensional histograms. A computer code is developed based on the K-Means algorithm and applied to find the learning period in which error rates are monotonously decreasing with plant age. The Freeman-Tukey (F-T) deviates are used to select generic problems identified by a large positive value (here approximately over 2.0) for the deviate. The identified generic problems are: decision errors which are highly associated with reactor startup operations in the learning period of PWR plants (PWRs), response errors which are highly associated with Secondary Non-Nuclear Systems (SNS) in PWRs, and significant errors affecting systems and which are caused by response action are highly associated with startup reactor mode in BWRS

  4. Modernization of turbines in fossil and nuclear power plants

    International Nuclear Information System (INIS)

    Harig, T.; Oeynhausen, H.

    2004-01-01

    Steam turbine power plants have a big share in power generation world-wide. In view of their age structure, they offer the biggest potential for increasing power plant performance, availability and environmental protection. Modernisation and replacement of key components by improved components will reduce fuel consumption and improve power plant performance by higher capacity, higher power, shorter start-up and shutdown times, and reduced standstill times. Modern steam turbine bladings will result in further improvements without additional fuel consumption. (orig.)

  5. Some power uprate issues in nuclear power plants

    International Nuclear Information System (INIS)

    Tipping, Philip

    2008-01-01

    Issues and themes concerned with nuclear power plant uprating are examined. Attention is brought to the fact that many candidate nuclear power plants for uprating have anyway been operated below their rated power for a significant part of their operating life. The key issues remain safety and reliability in operation at all times, irrespective of the nuclear power plant's chronological or design age or power rating. The effects of power uprates are discussed in terms of material aspects and expected demands on the systems, structures and components. The impact on operation and maintenance methods is indicated in terms of changes to the ageing surveillance programmes. Attention is brought to the necessity checking or revising operator actions after power up-rating has been implemented

  6. The power of PowerPoint.

    Science.gov (United States)

    Niamtu , J

    2001-08-01

    Carousel slide presentations have been used for academic and clinical presentations since the late 1950s. However, advances in computer technology have caused a paradigm shift, and digital presentations are quickly becoming standard for clinical presentations. The advantages of digital presentations include cost savings; portability; easy updating capability; Internet access; multimedia functions, such as animation, pictures, video, and sound; and customization to augment audience interest and attention. Microsoft PowerPoint has emerged as the most popular digital presentation software and is currently used by many practitioners with and without significant computer expertise. The user-friendly platform of PowerPoint enables even the novice presenter to incorporate digital presentations into his or her profession. PowerPoint offers many advanced options that, with a minimal investment of time, can be used to create more interactive and professional presentations for lectures, patient education, and marketing. Examples of advanced PowerPoint applications are presented in a stepwise manner to unveil the full power of PowerPoint. By incorporating these techniques, medical practitioners can easily personalize, customize, and enhance their PowerPoint presentations. Complications, pitfalls, and caveats are discussed to detour and prevent misadventures in digital presentations. Relevant Web sites are listed to further update, customize, and communicate PowerPoint techniques.

  7. Multicoil resonance-based parallel array for smart wireless power delivery.

    Science.gov (United States)

    Mirbozorgi, S A; Sawan, M; Gosselin, B

    2013-01-01

    This paper presents a novel resonance-based multicoil structure as a smart power surface to wirelessly power up apparatus like mobile, animal headstage, implanted devices, etc. The proposed powering system is based on a 4-coil resonance-based inductive link, the resonance coil of which is formed by an array of several paralleled coils as a smart power transmitter. The power transmitter employs simple circuit connections and includes only one power driver circuit per multicoil resonance-based array, which enables higher power transfer efficiency and power delivery to the load. The power transmitted by the driver circuit is proportional to the load seen by the individual coil in the array. Thus, the transmitted power scales with respect to the load of the electric/electronic system to power up, and does not divide equally over every parallel coils that form the array. Instead, only the loaded coils of the parallel array transmit significant part of total transmitted power to the receiver. Such adaptive behavior enables superior power, size and cost efficiency then other solutions since it does not need to use complex detection circuitry to find the location of the load. The performance of the proposed structure is verified by measurement results. Natural load detection and covering 4 times bigger area than conventional topologies with a power transfer efficiency of 55% are the novelties of presented paper.

  8. Electric vehicle recycling 2020: Key component power electronics.

    Science.gov (United States)

    Bulach, Winfried; Schüler, Doris; Sellin, Guido; Elwert, Tobias; Schmid, Dieter; Goldmann, Daniel; Buchert, Matthias; Kammer, Ulrich

    2018-04-01

    Electromobility will play a key role in order to reach the specified ambitious greenhouse gas reduction targets in the German transport sector of 42% between 1990 and 2030. Subsequently, a significant rise in the sale of electric vehicles (EVs) is to be anticipated in future. The amount of EVs to be recycled will rise correspondingly after a delay. This includes the recyclable power electronics modules which are incorporated in every EV as an important component for energy management. Current recycling methods using car shredders and subsequent post shredder technologies show high recycling rates for the bulk metals but are still associated with high losses of precious and strategic metals such as gold, silver, platinum, palladium and tantalum. For this reason, the project 'Electric vehicle recycling 2020 - key component power electronics' developed an optimised recycling route for recycling power electronics modules from EVs which is also practicable in series production and can be implemented using standardised technology. This 'WEEE recycling route' involves the disassembly of the power electronics from the vehicle and a subsequent recycling in an electronic end-of-life equipment recycling plant. The developed recycling process is economical under the current conditions and raw material prices, even though it involves considerably higher costs than recycling using the car shredder. The life cycle assessment shows basically good results, both for the traditional car shredder route and the developed WEEE recycling route: the latter provides additional benefits from some higher recovery rates and corresponding credits.

  9. A proposal to investigate higher enthalpy geothermal systems in the USA

    Science.gov (United States)

    Elders, W. A.

    2013-12-01

    After more than 50 years of development only ~3,400 MWe of electric power is currently being produced from geothermal resources in the USA. That is only about 0.33% of the country's total installed electrical capacity. In spite of the large demonstrated potential of geothermal resources, only ~2,500 MWe of new geothermal electrical capacity are under development, and the growth rate of this environmentally benign energy resource is overshadowed by the rapid increase in the installed capacity of wind and solar energy. Most of the new geothermal developments in the USA involve relatively small, moderate-temperature, geothermal systems. In contrast, development of higher enthalpy geothermal systems for power production has obvious advantages; specifically higher temperatures yield higher power outputs per well so that fewer wells are needed, leading to smaller environmental footprints for a given size of power plant. Disadvantages include that the fact that locations of suitable geothermal systems are restricted to young volcanic terrains, production of very high enthalpy fluids usually requires drilling deeper wells and may require enhanced geothermal (EGS) technology, and drilling deep into hot hostile environments is technologically challenging. However the potential for very favorable economic returns suggests that the USA should begin developing such a program. One approach to mitigating the cost issue is to form a consortium of industry, government and academia to share the costs and broaden the scope an investigation. An excellent example of such a collaboration is the Iceland Deep Drilling Project (IDDP) which is investigating the economic feasibility of producing electricity from supercritical geothermal reservoirs. This industry-government consortium planned to drill a deep well in the volcanic caldera of Krafla in NE Iceland. However drilling had to be terminated at 2.1 km depth when 900°C rhyolite magma flowed into the well. The resultant well was highly

  10. The effects of training with loads that maximise power output and individualised repetitions vs. traditional power training

    Science.gov (United States)

    Moya-Ramón, M.; Hernández-Davó, J. L.; Fernandez-Fernandez, J.; Sabido, R.

    2017-01-01

    Background It has been suggested that strength training effects (i.e. neural or structural) vary, depending on the total repetitions performed and velocity loss in each training set. Purpose The aim of this study is to compare the effects of two training programmes (i.e. one with loads that maximise power output and individualised repetitions, and the other following traditional power training). Methods Twenty-five males were divided into three groups (optimum power [OP = 10], traditional training [TT = 9] and control group [CG = 6]). The training load used for OP was individualised using loads that maximised power output (41.7% ± 5.8 of one repetition maximum [1RM]) and repetitions at maximum power (4 to 9 repetitions, or ‘reps’). Volume (sets x repetitions) was the same for both experimental groups, while intensity for TT was that needed to perform only 50% of the maximum number of possible repetitions (i.e. 61.1%–66.6% of 1RM). The training programme ran over 11 weeks (2 sessions per week; 4–5 sets per session; 3-minute rests between sets), with pre-, intermediate and post-tests which included: anthropometry, 1RM, peak power output (PPO) with 30%, 40% and 50% of 1RM in the bench press throw, and salivary testosterone (ST) and cortisol (SC) concentrations. Rate of perceived exertion (RPE) and power output were recorded in all sessions. Results Following the intermediate test, PPO was increased in the OP group for each load (10.9%–13.2%). Following the post-test, both experimental groups had increased 1RM (11.8%–13.8%) and PPO for each load (14.1%–19.6%). Significant decreases in PPO were found for the TT group during all sets (4.9%–15.4%), along with significantly higher RPE (37%). Conclusion OP appears to be a more efficient method of training, with less neuromuscular fatigue and lower RPE. PMID:29053725

  11. Comparative gross domestic production and electricity consumption per capita in the context of nuclear power prospect

    International Nuclear Information System (INIS)

    Ridzuan Abdul Mutalib; Maragatham Kumar; Nik Arlina Nik Ali; Abi Muttaqin Jalal Bayar; Aisya Raihan Abdul Kadir; Muhammed Zulfakar Zolkaffly; Azlinda Aziz; Jamal Khaer Ibrahim

    2008-08-01

    Malaysia, based on its economic and industrial growth level should be able to absorb nuclear technology and capacity in implementing a nuclear power programme. Malaysia Gross Domestic Production (GDP) and electricity consumption (kWh per capita is higher compared with other developing countries, which have already announced their plans to implement nuclear power programme. Furthermore, Asia reliance on nuclear power plants to meet growing energy needs in the near future is also significantly increasing. This paper presents the comparative GDP and kWh per capita in Asia and globally in the context of nuclear power prospect in Malaysia. (Author)

  12. Assessment by three-dimensional power Doppler ultrasound of cerebral blood flow perfusion in fetuses with congenital heart disease.

    Science.gov (United States)

    Zeng, S; Zhou, J; Peng, Q; Tian, L; Xu, G; Zhao, Y; Wang, T; Zhou, Q

    2015-06-01

    To use three-dimensional (3D) power Doppler ultrasound to investigate cerebral blood flow perfusion in fetuses with congenital heart disease (CHD). The vascularization index (VI), flow index (FI) and vascularization flow index (VFI) in the total intracranial volume and the main arterial territories (middle cerebral artery (MCA), anterior cerebral artery (ACA) and posterior cerebral artery (PCA)) were evaluated prospectively and compared in 112 fetuses with CHD and 112 normal fetuses using 3D power Doppler. Correlations between the 3D power Doppler indices and neurodevelopment scores at 12 months of age were assessed in a subset of the CHD group, and values were compared with those of controls. Compared with the controls, the VI, FI and VFI of the total intracranial volume and the three main arteries were significantly higher in fetuses with hypoplastic left heart syndrome and left-sided obstructive lesions (P power Doppler values in the ACA territory were significantly higher in fetuses with transposition of the great arteries (P power Doppler ultrasound might help to identify cases of brain vasodilatation earlier and inform parental counseling. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

  13. Effect of caffeine intake on critical power model parameters determined on a cycle ergometer

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius Machado

    2010-01-01

    Full Text Available The aim of this study was to evaluate the effect of caffeine intake on critical power model parameters determined on a cycle ergometer. Eight male subjects participated in this study. A double-blind protocol consisting of the intake of pure caffeine (6 mg/kg or placebo (maltodextrin 60 min before testing was used. Subjects were submitted to four constant-load tests on a cycle ergometer. These tests were conducted randomly in the caffeine and placebo groups [checar] at intensities of 80, 90, 100 and 110% maximum power at a rate of 70 rpm until exhaustion to determine the critical power. As a criterion for stopping the test was adopted any rate fall without recovery by more than five seconds. The critical power and anaerobic work capacity were obtained by nonlinear regression and fitting of the curve to a hyperbolic power-time model. The Shapiro-Wilk test and paired Student t-test were used for statistical analysis. No significant differences in critical power were observed between the caffeine and placebo groups (192.9 ± 31.3 vs 197.7 ± 29.4 W, respectively. The anaerobic work capacity was significantly higher in the caffeine group (20.1 ± 5.2 vs 16.3 ± 4.2 W, p< 0.01. A high association (r2 was observed between the caffeine and placebo conditions (0.98 ± 0.02 and 0.99 ± 0.0, respectively. We conclude that caffeine intake did not improve critical power performance but increased anaerobic work capacity by influencing performance at loads of higher intensity and shorter duration.

  14. Using a higher criticism statistic to detect modest effects in a genome-wide study of rheumatoid arthritis

    Science.gov (United States)

    2009-01-01

    In high-dimensional studies such as genome-wide association studies, the correction for multiple testing in order to control total type I error results in decreased power to detect modest effects. We present a new analytical approach based on the higher criticism statistic that allows identification of the presence of modest effects. We apply our method to the genome-wide study of rheumatoid arthritis provided in the Genetic Analysis Workshop 16 Problem 1 data set. There is evidence for unknown bias in this study that could be explained by the presence of undetected modest effects. We compared the asymptotic and empirical thresholds for the higher criticism statistic. Using the asymptotic threshold we detected the presence of modest effects genome-wide. We also detected modest effects using 90th percentile of the empirical null distribution as a threshold; however, there is no such evidence when the 95th and 99th percentiles were used. While the higher criticism method suggests that there is some evidence for modest effects, interpreting individual single-nucleotide polymorphisms with significant higher criticism statistics is of undermined value. The goal of higher criticism is to alert the researcher that genetic effects remain to be discovered and to promote the use of more targeted and powerful studies to detect the remaining effects. PMID:20018032

  15. Knowledge, Power and Meanings Shaping Quality Assurance in Higher Education: A Systemic Critique

    Science.gov (United States)

    Houston, Don; Paewai, Shelley

    2013-01-01

    Internationally, quality assurance schemes persist despite long-standing dissatisfaction and critique of their impact and outcomes. Adopting a critical systems perspective, the article explores the relationships between the knowledge, power and meanings that stakeholder groups bring to the design and implementation of quality assurance systems.…

  16. A High-Efficiency Compact SiC-based Power Converter System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Wide bandgap SiC power devices have the potential for reliable operations at higher junction temperatures, higher voltages, higher frequencies and thus higher power...

  17. Radiation resistance of wide-bandgap semiconductor power transistors

    Energy Technology Data Exchange (ETDEWEB)

    Hazdra, Pavel; Popelka, Stanislav [Department of Microelectronics, Czech Technical University in Prague (Czech Republic)

    2017-04-15

    Radiation resistance of state-of-the-art commercial wide-bandgap power transistors, 1700 V 4H-SiC power MOSFETs and 200 V GaN HEMTs, to the total ionization dose was investigated. Transistors were irradiated with 4.5 MeV electrons with doses up to 2000 kGy. Electrical characteristics and introduced defects were characterized by current-voltage (I-V), capacitance-voltage (C-V), and deep level transient spectroscopy (DLTS) measurements. Results show that already low doses of 4.5 MeV electrons (>1 kGy) cause a significant decrease in threshold voltage of SiC MOSFETs due to embedding of the positive charge into the gate oxide. On the other hand, other parameters like the ON-state resistance are nearly unchanged up to the dose of 20 kGy. At 200 kGy, the threshold voltage returns back close to its original value, however, the ON-state resistance increases and transconductance is lowered. This effect is caused by radiation defects introduced into the low-doped drift region which decrease electron concentration and mobility. GaN HEMTs exhibit significantly higher radiation resistance. They keep within the datasheet specification up to doses of 2000 kGy. Absence of dielectric layer beneath the gate and high concentration of carriers in the two dimensional electron gas channel are the reasons of higher radiation resistance of GaN HEMTs. Their degradation then occurs at much higher doses due to electron mobility degradation. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Examination of risk significant configuration during low power and shutdown with ORION and PSA

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chul Kyu; Oh, Seung Jong [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2015-10-15

    This paper suggests an approach to calculate the increased CDF corresponding to Orange and Red states in ORION program and analyzed the result of calculation. This approach is expected to be useful for checking the adequacy of the LPSD PSA. And also, the result of this calculation can provide the information about which SSCs for certain SF are more sensitive to risk in particular POS. Defense-in-depth is a safety philosophy in which multiple lines of defense and conservative design and evaluation methods are applied to ensure the safety of the public. Based on this philosophy EPRI developed Outage Risk Assessment and Management (ORAM) program as a qualitative assessment to better manage the risk during low power and shutdown event after the Vogtle loss of vital AC power and RHR event in 1990. Each risk level of RED, ORANGE color status caused by the degradation of each key safety function might be different depend on the importance of each key safety function. However we can't know how much different. If we know the quantitative information about the risk level represented by color, we can take and prepare concrete actions to reduce the risk level of the plant with rescheduling maintenance, strengthen surveillance for important safety function, and developing outage management strategy. The probabilistic safety analysis for low power and shutdown period can provide risk information with quantitative value related on the degradation of redundancy and diversity level for the safety functions during outage. In this study, we calculated the increased Core Damage frequency (CDF) of each RED and ORANGE states in ORION program caused by the degradation of each key safety function by modifying LPSD PSA model. The result of calculation and analysis could be effective to check adequacy and find improvement for these two methods.

  19. Radioisotope AMTEC power system designs for spacecraft applications

    International Nuclear Information System (INIS)

    Ivanenok, J.F. III; Sievers, R.K.; Hunt, T.K.; Johnson, G.A.

    1993-01-01

    The Alkali Metal Thermal to Electric Converter (AMTEC) system is an exceptional candidate for high performance spacecraft power systems including small systems powered by General Purpose Heat Sources (GPHS). The AMTEC converter is best described as a thermally regenerative electrochemical concentration cell. AMTEC is a static energy conversion device and can operate at efficiencies between 15% and 30%. The single tube, remote condensed, wick return minicell design has been incorporated into a radioisotope powered system model. Reported cell efficiencies used for these system design studies ranged from 15% to 25%. This efficiency is significantly higher than other static conversion systems operating at the same temperatures. Savings in mass and cost, relative to other more conventional static conversion systems, have also been shown. The minicell used for this system study has many advanced features not combined in previous designs, including wick return, remote condensing, and hot zone feedthroughs. All of these features significantly enhance the performance of the AMTEC cell. Additionally, the cell end provides enough area for adequate heat transfer from the GPHS module, eliminating the need for a ''hot shoe'', and reducing the complexity and weight of the system. This paper describes and compares small (two module) and larger (16 module) AMTEC radioisotope powered systems and describes the computer model developed to predict their performance

  20. KOREAN STUDENTS' BEHAVIORAL CHANGE TOWARD NUCLEAR POWER GENERATION THROUGH EDUCATION

    Directory of Open Access Journals (Sweden)

    EUN OK HAN

    2014-10-01

    Full Text Available As a result of conducting a 45 minute-long seminar on the principles, state of use, advantages, and disadvantages of nuclear power generation for Korean elementary, middle, and high school students, the levels of perception including the necessity (p<0.017, safety (p<0.000, information acquisition (p<0.000, and subjective knowledge (p<0.000, objective knowledge (p<0.000, attitude (p<0.000, and behavior (p<0.000 were all significantly higher. This indicates that education can be effective in promoting widespread social acceptance of nuclear power and its continued use. In order to induce behavior change toward positive judgments on nuclear power generation, it is necessary to focus on attitude improvement while providing the information in all areas related to the perception, knowledge, attitude, and behavior. Here, the positive message on the convenience and the safety of nuclear power generation should be highlighted.

  1. Are powerful females powerful enough? Acceleration in gravid green iguanas (Iguana iguana).

    Science.gov (United States)

    Scales, Jeffrey; Butler, Marguerite

    2007-08-01

    One demand placed exclusively on the musculoskeletal system of females is maintaining locomotor performance with an increasing load over the reproductive cycle. Here, we examine whether gravid (i.e., "pregnant") iguanas can increase their force and power production to support, stabilize, and accelerate the additional mass of a clutch of eggs. At any acceleration, gravid iguanas produced very high mechanical power (average total power = 673 w/kg; total peak power = 1175 w/kg). While the increase in total power was partly a result of greater propulsive power (average propulsive power = 25% higher, peak propulsive power = 38% higher), increased vertical power (roughly 200% increase) was the main contributor. Gravid iguanas were also able to increase peak forces (propulsive = 23%, mediolateral = 44%, vertical = 42%), and step duration (44%) resulting in greater impulses (i.e., the sum of force produced during a step) to accelerate, balance, and support their increased mass. The increase in step duration and smaller increase in peak propulsive force suggests that gravid iguanas may be force-limited in the direction of motion. We discuss how biomechanical constraints due to females' reproductive role may influence the evolution of the female musculoskeletal systems and contribute to the evolution and maintenance of ecological dimorphism in lizards.

  2. Comparison and evaluation of nuclear power plant options for geosynchronous power stations

    International Nuclear Information System (INIS)

    Williams, J.R.

    1975-01-01

    A solution to the safety, safeguards, and radwaste disposal problems of nuclear power is to locate the breeder reactor power plants far out in geosynchronous orbit and beam the power to earth with microwaves. The generation of nuclear power in space is technologically feasible and has already been demonstrated on a small scale. It has also been shown that high efficiency microwave transmission of power from synchronous orbit to earth is feasible and is not hazardous. The reactor safety problem would be virtually eliminated because of the remoteness of the satellite power station in geosynchronous orbit. The worst possible accident at such a plant would have negligible effect on the earth, certainly less than the high altitude nuclear explosions which have been conducted in the past. Accidental re-entry from geosynchronous orbit could not occur because of the very large velocity change required. The safeguards problem can be virtually eliminated by adopting the following procedures: 1) The plant is initially started up using U-235 fuel or bred plutonium or U-233 from another geosynchronous power plant, 2) Once the plant is operating, only nonhazardous fertile materials (thorium or depleted uranium) are shipped up from earth, 3) The fissile fuel is bred and used in space, and none of this highly toxic fissile material is ever returned to earth. The radioactive waste could be concentrated and ejected in canisters into deep space away from the earth. The geosynchronous nuclear power plant offers unlimited nuclear power without nuclear hazards or nuclear pollution, but at somewhat higher cost. Whether or not society will be willing to pay these higher costs of nuclear power from space, or whether new energy resources such as nuclear fusion or solar power become feasible, remains to be seen. A prudent course to follow would be to give careful consideration to all future options for large scale energy generation, including the option of nuclear power from space

  3. Less Physician Practice Competition Is Associated With Higher Prices Paid For Common Procedures.

    Science.gov (United States)

    Austin, Daniel R; Baker, Laurence C

    2015-10-01

    Concentration among physician groups has been steadily increasing, which may affect prices for physician services. We assessed the relationship in 2010 between physician competition and prices paid by private preferred provider organizations for fifteen common, high-cost procedures to understand whether higher concentration of physician practices and accompanying increased market power were associated with higher prices for services. Using county-level measures of the concentration of physician practices and county average prices, and statistically controlling for a range of other regional characteristics, we found that physician practice concentration and prices were significantly associated for twelve of the fifteen procedures we studied. For these procedures, counties with the highest average physician concentrations had prices 8-26 percent higher than prices in the lowest counties. We concluded that physician competition is frequently associated with prices. Policies that would influence physician practice organization should take this into consideration. Project HOPE—The People-to-People Health Foundation, Inc.

  4. Power and LPG production with LNG import

    International Nuclear Information System (INIS)

    Mak, J.Y.

    2004-01-01

    When used in power cogeneration, Liquefied Natural Gas (LNG) is both energy efficient and can eliminate seawater or fuel gas consumption as well as the associated environmental impacts of conventional regasification processes. However, some liquefied natural gas (LNG) sources have heating values higher than current North American natural gas pipelines can allow for. LNG from these cannot be injected into gas pipelines without several heating control processing steps. This paper outlines two new technologies developed to address this issue. The first is a power cogeneration process using LNG as a heat sink. The second technology involves a fractionation process removing Liquid Propane Gas (LPG) components from imported LNG, thereby controlling heat value. Both technologies are applicable in grassroots installations as well as being suitable for retrofitting to existing LNG regasification for power generation and LPG production. It was concluded that power cogeneration with a mixed fluid power cycle recovered a significant portion of energy in LNG liquefaction plants. Additionally, it was also possible to fractionate high quality LPG from LNG at a low cost, with the residue being further re-condensed and re-utilized for power generation. It was also concluded that the LNG fractionation process would add flexibility to the LNG receiving terminals, allowing the import of lower quality LNG to North America, while also generating additional revenues from LPG production. 3 refs., 5 tabs., 6 figs

  5. Influence of Power Pulse Parameters on the Microstructure and Properties of the AlCrN Coatings by a Modulated Pulsed Power Magnetron Sputtering

    Directory of Open Access Journals (Sweden)

    Jun Zheng

    2017-11-01

    Full Text Available In this study, AlCrN coatings were deposited using modulated pulsed power magnetron sputtering (MPPMS with different power pulse parameters by varying modulated pulsed power (MPP charge voltages (350 to 550 V. The influence of power pulse parameters on the microstructure, mechanical properties and thermal stability of the coatings was investigated. The results indicated that all the AlCrN coatings exhibited a dense columnar microstructure. Higher charge voltage could facilitate a denser coating microstructure. As the charge voltage increased up to 450 V or higher, the microvoids along the column boundaries disappeared and the coatings became fully dense. The main phase in the AlCrN coatings was the c-(Al, CrN solid solution phase with NaCl-type phase structure. A diffraction peak of the h-AlN phase was detected at a 2θ of around 33°, when the charge voltage was higher than 500 V. The hardness of the AlCrN coatings varied as a function of charge voltage. The maximum value of the hardness (30.8 GPa was obtained at 450 V. All the coatings showed good thermal stability and maintained their structure and mechanical properties unchanged up to 800 °C during vacuum annealing. However, further increasing the annealing temperature to 1000 °C resulted in apparent change in the microstructure and decrease in the hardness. The charge voltages also showed a significant influence on the high-temperature tribological behavior of the coatings. The coating deposited at the charge voltage of 550 V exhibited excellent tribological properties with a low friction coefficient.

  6. Shared Leadership Transforms Higher Education IT

    Science.gov (United States)

    Duin, Ann Hill; Cawley, Steve; Gulachek, Bernard; O'Sullivan, Douglas M.; Wollner, Diane

    2011-01-01

    Globalization, immersive research and learning environments, unlimited access to information and analytics, and fiscal realities continue to impact higher education--and higher education IT. Although IT organizations face immense pressure to meet significantly greater expectations at significantly less cost, with such pressure comes the…

  7. High-Power Electron Accelerators for Space (and other) Applications

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Dinh Cong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lewellen, John W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-23

    This is a presentation on high-power electron accelerators for space and other applications. The main points covered are: electron beams for space applications, new designs of RF accelerators, high-power high-electron mobility transistors (HEMT) testing, and Li-ion battery design. In summary, the authors have considered a concept of 1-MeV electron accelerator that can operate up to several seconds. This concept can be extended to higher energy to produce higher beam power. Going to higher beam energy requires adding more cavities and solid-state HEMT RF power devices. The commercial HEMT have been tested for frequency response and RF output power (up to 420 W). Finally, the authors are testing these HEMT into a resonant load and planning for an electron beam test in FY17.

  8. Toward power scaling in an acetylene mid-infrared hollow-core optical fiber gas laser: effects of pressure, fiber length, and pump power

    Science.gov (United States)

    Weerasinghe, H. W. Kushan; Dadashzadeh, Neda; Thirugnanasambandam, Manasadevi P.; Debord, Benoît.; Chafer, Matthieu; Gérôme, Frédéric; Benabid, Fetah; Corwin, Kristan L.; Washburn, Brian R.

    2018-02-01

    The effect of gas pressure, fiber length, and optical pump power on an acetylene mid-infrared hollow-core optical fiber gas laser (HOFGLAS) is experimentally determined in order to scale the laser to higher powers. The absorbed optical power and threshold power are measured for different pressures providing an optimum pressure for a given fiber length. We observe a linear dependence of both absorbed pump energy and lasing threshold for the acetylene HOFGLAS, while maintaining a good mode quality with an M-squared of 1.15. The threshold and mode behavior are encouraging for scaling to higher pressures and pump powers.

  9. Neural classifiers for learning higher-order correlations

    International Nuclear Information System (INIS)

    Gueler, M.

    1999-01-01

    Studies by various authors suggest that higher-order networks can be more powerful and biologically more plausible with respect to the more traditional multilayer networks. These architecture make explicit use of nonlinear interactions between input variables in the form of higher-order units or product units. If it is known a priori that the problem to be implemented possesses a given set of invariances like in the translation, rotation, and scale invariant recognition problems, those invariances can be encoded, thus eliminating all higher-order terms which are incompatible with the invariances. In general, however, it is a serious set-back that the complexity of learning increases exponentially with the size of inputs. This paper reviews higher-order networks and introduces an implicit representation in which learning complexity is mainly decided by the number of higher-order terms to be learned and increases only linearly with the input size

  10. Neural Classifiers for Learning Higher-Order Correlations

    Science.gov (United States)

    Güler, Marifi

    1999-01-01

    Studies by various authors suggest that higher-order networks can be more powerful and are biologically more plausible with respect to the more traditional multilayer networks. These architectures make explicit use of nonlinear interactions between input variables in the form of higher-order units or product units. If it is known a priori that the problem to be implemented possesses a given set of invariances like in the translation, rotation, and scale invariant pattern recognition problems, those invariances can be encoded, thus eliminating all higher-order terms which are incompatible with the invariances. In general, however, it is a serious set-back that the complexity of learning increases exponentially with the size of inputs. This paper reviews higher-order networks and introduces an implicit representation in which learning complexity is mainly decided by the number of higher-order terms to be learned and increases only linearly with the input size.

  11. Global wind power development: Economics and policies

    International Nuclear Information System (INIS)

    Timilsina, Govinda R.; Cornelis van Kooten, G.; Narbel, Patrick A.

    2013-01-01

    Existing literature indicates that theoretically, the earth's wind energy supply potential significantly exceeds global energy demand. Yet, only 2–3% of global electricity demand is currently derived from wind power despite 27% annual growth in wind generating capacity over the last 17 years. More than 95% of total current wind power capacity is installed in the developed countries plus China and India. Our analysis shows that the economic competitiveness of wind power varies at wider range across countries or locations. A climate change damage cost of US$20/tCO 2 imposed to fossil fuels would make onshore wind competitive to all fossil fuels for power generation; however, the same would not happen to offshore wind, with few exceptions, even if the damage cost is increased to US$100/tCO 2 . To overcome a large number of technical, financial, institutional, market and other barriers to wind power, many countries have employed various policy instruments, including capital subsidies, tax incentives, tradable energy certificates, feed-in tariffs, grid access guarantees and mandatory standards. Besides, climate change mitigation policies, such as the Clean Development Mechanism, have played a pivotal role in promoting wind power. Despite these policies, intermittency, the main technical constraint, could remain as the major challenge to the future growth of wind power. - Highlights: • Global wind energy potential is enormous, yet the wind energy contribution is very small. • Existing policies are boosting development of wind power. • Costs of wind energy are higher than cost of fossil-based energies. • Reasonable premiums for climate change mitigation substantially promote wind power. • Intermittency is the key challenge to future development of wind power

  12. PowerFilm PowerShade Fixed Site Solar System Cost Reduction Plan

    Science.gov (United States)

    2014-07-31

    system was designed which adds capability of grid tie connection to the standalone function. This battery operating system has built-in intelligence...goal concerning alternative conductive grid inks was to reduce the cost of the silver ink layer without a reduction in PV power with experimentation... system . To overcome this loss, a new BOS unit with higher power transfer efficiency has been developed. This system also has grid tie

  13. The use of BEACON monitoring in plant power uprates

    International Nuclear Information System (INIS)

    Miller, Wade

    2003-01-01

    BEACON is the core support software technology that provides Utilities with continuous 3-D core power distribution monitoring, operational analysis capability, and operations support capability. BEACON monitoring delivers quantifiable plant margins for both reload design and plant operations improvement. When linked to Plant Power Upratings, BEACON permits an improvement in fuel cycle economics through higher peaking factors, higher power levels and higher discharge burnups. Operational flexibility of Uprated Plants is enhanced through elimination of axial power shape and core power tilt specifications. Also, the number of flux maps for these plants is reduced and local power is monitored continuously, permitting faster power escalation. Integrated 3-D power distribution analysis capabilities provide core designers with historical margin data that permits a reduction in core follow requirements as well as reduced curve book data related scope. Examples of specific Uprated Plant applications will be discussed. In anticipation of future needs of Uprated Plants, plans to integrate the technology of BEACON with COLSS are being executed. Finally, the capability to monitor Crud Induced Power Shift (axial offset) is also planned for incorporation into BEACON in the near future and will be discussed

  14. Significance of relative velocity in drag force or drag power estimation for a tethered float

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.; Sastry, J.S.

    There is difference in opinion regarding the use of relative velocity instead of particle velocity alone in the estimation of drag force or power. In the present study, a tethered spherical float which undergoes oscillatory motion in regular waves...

  15. Influence of high burnup on the decay heat power of spent fuel at long-term storage

    International Nuclear Information System (INIS)

    Bergelson, B.; Gerasimov, A.; Tikhomirov, G.

    2005-01-01

    Development and application of advanced fuel with higher burnup is now in practice of NPP with light water reactors in an increasing number of countries. High burnup allows to decrease significantly consumption of uranium. However, spent fuel of this type contains increased amount of high active actinides and fission products in comparison with spent fuel of common-type burnup. Therefore extended time of storage, improved cooling system of the storage facility will be required along with more strong radiation protection during storage, transportation and processing. Calculated data on decay heat power of spent uranium fuel of light water VVER-1000 type reactor are discussed in the paper. Long-term storage of discharged fuel during 100000 years is considered. Calculations were made for burnups of 40-70 MW d/kg. In the initial 50-year period of storage, power of fission products is much higher than that of actinides. Power of gamma-radiation is mainly due to fission products. During subsequent storage power of fission products quickly decreases, the main contribution to the power is given by actinides rather than by fission products. (author)

  16. Positional accommodative intraocular lens power error induced by the estimation of the corneal power and the effective lens position

    Directory of Open Access Journals (Sweden)

    David P Piñero

    2015-01-01

    Full Text Available Purpose: To evaluate the predictability of the refractive correction achieved with a positional accommodating intraocular lenses (IOL and to develop a potential optimization of it by minimizing the error associated with the keratometric estimation of the corneal power and by developing a predictive formula for the effective lens position (ELP. Materials and Methods: Clinical data from 25 eyes of 14 patients (age range, 52-77 years and undergoing cataract surgery with implantation of the accommodating IOL Crystalens HD (Bausch and Lomb were retrospectively reviewed. In all cases, the calculation of an adjusted IOL power (P IOLadj based on Gaussian optics considering the residual refractive error was done using a variable keratometric index value (n kadj for corneal power estimation with and without using an estimation algorithm for ELP obtained by multiple regression analysis (ELP adj . P IOLadj was compared to the real IOL power implanted (P IOLReal , calculated with the SRK-T formula and also to the values estimated by the Haigis, HofferQ, and Holladay I formulas. Results: No statistically significant differences were found between P IOLReal and P IOLadj when ELP adj was used (P = 0.10, with a range of agreement between calculations of 1.23 D. In contrast, P IOLReal was significantly higher when compared to P IOLadj without using ELP adj and also compared to the values estimated by the other formulas. Conclusions: Predictable refractive outcomes can be obtained with the accommodating IOL Crystalens HD using a variable keratometric index for corneal power estimation and by estimating ELP with an algorithm dependent on anatomical factors and age.

  17. Higher-order amplitude squeezing of photons propagating through a semiconductor

    International Nuclear Information System (INIS)

    Nguyen Ba An.

    1996-12-01

    Photon amplitude K th power squeezing is studied when the coherent photon propagates through a semiconductor containing the exciton. If the exciton is prepared initially in a coherent state, the photon may become amplitude K th power squeezed. It is shown that, in the short-time limit, the photon squeezing in the P direction does not appear at all while that in the X direction is possible for all the amplitude power K. In the latter case, the amount of squeezing is larger for higher power K. Dependences on all the system parameters as well as on the output light detection moment are investigated in detail. (author). 14 refs, 8 figs

  18. Reversing nuclear power cost trends

    International Nuclear Information System (INIS)

    Corey, G.R.; Peoples, D.L.

    1988-01-01

    Nuclear power production expenses rose steadily during the 5-year period 1979 through 1984 at rates ranging from 15 to 25% per year for nonfuel expenses. During that period, fuel costs rose about 14% per year. Experience of the past few years demonstrates that significant economies-of-scale do exist in plant operation and maintenance. A regional operating company could exploit such economies-of-scale and would also be expected to attract and retain a more-experienced and stable staff. Over the years, that combination should significantly improve plant operating performance and safety. The net effect would be a combination of reduced operating expenses; improved availability; higher capacity factors; and, possibly, lower heat rates. In an era of increasing competition within energy business, all options should be considered carefully. Bold innovation will be the key to a nuclear future. 5 references, 8 figures

  19. Gender, Power and Management: A Cross-Cultural Analysis of Higher Education

    Science.gov (United States)

    Bagilhole, Barbara, Ed.; White, Kate, Ed.

    2011-01-01

    Women are now part of senior management in higher education (HE) to varying degrees in most countries and actively contribute to the vision and strategic direction of universities. This book attempts to analyse their impact and potential impact on both organisational growth and culture. Contents of this book include: (1) Building a Feminist…

  20. A Doherty Power Amplifier with Large Back-Off Power Range Using Integrated Enhancing Reactance

    Directory of Open Access Journals (Sweden)

    Wa Kong

    2018-01-01

    Full Text Available A symmetric Doherty power amplifier (DPA based on integrated enhancing reactance (IER was proposed for large back-off applications. The IER was generated using the peaking amplifier with the help of a desired impedance transformation in the low-power region to enhance the back-off efficiency of the carrier amplifier. To convert the impedances properly, both in the low-power region and at saturation, a two-impedance matching method was employed to design the output matching networks. For verification, a symmetric DPA with large back-off power range over 2.2–2.5 GHz was designed and fabricated. Measurement results show that the designed DPA has the 9 dB back-off efficiency of higher than 45%, while the saturated output power is higher than 44 dBm over the whole operation bandwidth. When driven by a 20 MHz LTE signal, the DPA can achieve good average efficiency of around 50% with adjacent channel leakage ratio of about –50 dBc after linearization over the frequency band of interest. The linearity improvement of the DPA for multistandard wireless communication system was also verified with a dual-band modulated signal.

  1. Impact of Uncoordinated Plug-in Electric Vehicle Charging on Residential Power Demand

    Energy Technology Data Exchange (ETDEWEB)

    Muratori, Matteo [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2018-01-22

    Electrification of transport offers opportunities to increase energy security, reduce carbon emissions, and improve local air quality. Plug-in electric vehicles (PEVs) are creating new connections between the transportation and electric sectors, and PEV charging will create opportunities and challenges in a system of growing complexity. Here, I use highly resolved models of residential power demand and PEV use to assess the impact of uncoordinated in-home PEV charging on residential power demand. While the increase in aggregate demand might be minimal even for high levels of PEV adoption, uncoordinated PEV charging could significantly change the shape of the aggregate residential demand, with impacts for electricity infrastructure, even at low adoption levels. Clustering effects in vehicle adoption at the local level might lead to high PEV concentrations even if overall adoption remains low, significantly increasing peak demand and requiring upgrades to the electricity distribution infrastructure. This effect is exacerbated when adopting higher in-home power charging.

  2. Impact of uncoordinated plug-in electric vehicle charging on residential power demand

    Science.gov (United States)

    Muratori, Matteo

    2018-03-01

    Electrification of transport offers opportunities to increase energy security, reduce carbon emissions, and improve local air quality. Plug-in electric vehicles (PEVs) are creating new connections between the transportation and electric sectors, and PEV charging will create opportunities and challenges in a system of growing complexity. Here, I use highly resolved models of residential power demand and PEV use to assess the impact of uncoordinated in-home PEV charging on residential power demand. While the increase in aggregate demand might be minimal even for high levels of PEV adoption, uncoordinated PEV charging could significantly change the shape of the aggregate residential demand, with impacts for electricity infrastructure, even at low adoption levels. Clustering effects in vehicle adoption at the local level might lead to high PEV concentrations even if overall adoption remains low, significantly increasing peak demand and requiring upgrades to the electricity distribution infrastructure. This effect is exacerbated when adopting higher in-home power charging.

  3. Partner Positioning: Examining International Higher Education Partnerships through a Mutuality Lens

    Science.gov (United States)

    George Mwangi, Chrystal A.

    2017-01-01

    Scholarship on international higher education partnerships is often framed by strategic management and organization theories. These approaches are useful, but can minimize how power dynamics and positioning of partners impact engagement and outcomes. This study uses qualitative inquiry to examine 60 international higher education partnerships…

  4. Cost-effectiveness of low-power nuclear power plants

    International Nuclear Information System (INIS)

    Mitenkov, F.M.; Vostokov, V.S.; Drozhkin, V.N.; Samoilov, O.B.

    1994-01-01

    Many potential consumers of electricity and heat, consuming several thousands of kilowatts (up to 10-15 MW), have now been identified. This is significant primarily for regions far from power grids and other centralized sources of energy, such as, for example, Yakutiya, Northeastern Siberia, and elsewhere. These consumers are now supplied with fossil fuel, which is often difficult and expensive to deliver. For this reason it is very important to develop low-power nuclear power plants for remote regions

  5. Power reserve provision with wind farms. Grid integration of wind power

    Energy Technology Data Exchange (ETDEWEB)

    Gesino, Alejandro J.

    2011-07-01

    Wind power is, admittedly, different from other power technologies and integrating large amounts of it in the existing power systems is a challenge that requires innovative approaches to keep the sustainability of the power system operation. In the coming years its contribution to the system security will become mandatory as far as the trend goes towards more decentralized structures and an increase in complexity due to a higher number of market participants. This PhD addresses one of the fundamental ancillary services researching about a secure and flexible methodology for power reserve provision with wind farms. Based on the current needs and security standards of those highly developed European grid codes, a new model for power reserve provision with wind power is developed. This methodology, algorithms and variables are tested based on real scenarios from five German wind farm clusters. Finally, once the methodology for power reserve provision with wind power has been tested, real control capabilities from already installed wind farms in Germany and Portugal are analyzed. Their capabilities of following control commands as well as an error deviation analysis are also presented. (orig.)

  6. Site selection of active damper for stabilizing power electronics based power distribution system

    DEFF Research Database (Denmark)

    Yoon, Changwoo; Wang, Xiongfei; Bak, Claus Leth

    2015-01-01

    electronics based power device, which provides an adjustable damping capability to the power system where the voltage harmonic instability is measured. It can stabilize by adjusting the equivalent node impedance with its plug and play feature. This feature gives many degrees of freedom of its installation......Stability in the nowadays distribution power system is endangered by interaction problems that may arise from newly added power-electronics based power devices. Recently, a new concept to deal with this higher frequency instability, the active damper, has been proposed. The active damper is a power...... point when the system has many nodes. Therefore, this paper addresses the proper placement of an active damper in an unstable small-scale power distribution system. A time-domain model of the Cigre benchmark low-vltage network is used as a test field. The result shows the active damper location...

  7. Opportunity or Exploitation? Women and Quality Assurance in Higher Education

    Science.gov (United States)

    Morley, Louise

    2005-01-01

    Based on interviews with 18 UK women academics and managers on quality and power in higher education, this article interrogates the impact of quality assurance discourses and practices on women in higher education. Micro-level analysis of the effects of audit and the evaluative state seem to suggest that hegemonic masculinities and gendered power…

  8. Study on optimal configuration of the grid-connected wind-solar-battery hybrid power system

    Science.gov (United States)

    Ma, Gang; Xu, Guchao; Ju, Rong; Wu, Tiantian

    2017-08-01

    The capacity allocation of each energy unit in the grid-connected wind-solar-battery hybrid power system is a significant segment in system design. In this paper, taking power grid dispatching into account, the research priorities are as follows: (1) We establish the mathematic models of each energy unit in the hybrid power system. (2) Based on dispatching of the power grid, energy surplus rate, system energy volatility and total cost, we establish the evaluation system for the wind-solar-battery power system and use a number of different devices as the constraint condition. (3) Based on an improved Genetic algorithm, we put forward a multi-objective optimisation algorithm to solve the optimal configuration problem in the hybrid power system, so we can achieve the high efficiency and economy of the grid-connected hybrid power system. The simulation result shows that the grid-connected wind-solar-battery hybrid power system has a higher comprehensive performance; the method of optimal configuration in this paper is useful and reasonable.

  9. Graphene-based in-plane micro-supercapacitors with high power and energy densities.

    Science.gov (United States)

    Wu, Zhong-Shuai; Parvez, Khaled; Feng, Xinliang; Müllen, Klaus

    2013-01-01

    Micro-supercapacitors are important on-chip micro-power sources for miniaturized electronic devices. Although the performance of micro-supercapacitors has been significantly advanced by fabricating nanostructured materials, developing thin-film manufacture technologies and device architectures, their power or energy densities remain far from those of electrolytic capacitors or lithium thin-film batteries. Here we demonstrate graphene-based in-plane interdigital micro-supercapacitors on arbitrary substrates. The resulting micro-supercapacitors deliver an area capacitance of 80.7 μF cm⁻² and a stack capacitance of 17.9 F cm⁻³. Further, they show a power density of 495 W cm⁻³ that is higher than electrolytic capacitors, and an energy density of 2.5 mWh cm⁻³ that is comparable to lithium thin-film batteries, in association with superior cycling stability. Such microdevices allow for operations at ultrahigh rate up to 1,000 V s⁻¹, three orders of magnitude higher than that of conventional supercapacitors. Micro-supercapacitors with an in-plane geometry have great promise for numerous miniaturized or flexible electronic applications.

  10. Graphene-based in-plane micro-supercapacitors with high power and energy densities

    Science.gov (United States)

    Wu, Zhong–Shuai; Parvez, Khaled; Feng, Xinliang; Müllen, Klaus

    2013-01-01

    Micro-supercapacitors are important on-chip micro-power sources for miniaturized electronic devices. Although the performance of micro-supercapacitors has been significantly advanced by fabricating nanostructured materials, developing thin-film manufacture technologies and device architectures, their power or energy densities remain far from those of electrolytic capacitors or lithium thin-film batteries. Here we demonstrate graphene-based in-plane interdigital micro-supercapacitors on arbitrary substrates. The resulting micro-supercapacitors deliver an area capacitance of 80.7 μF cm−2 and a stack capacitance of 17.9 F cm−3. Further, they show a power density of 495 W cm−3 that is higher than electrolytic capacitors, and an energy density of 2.5 mWh cm−3 that is comparable to lithium thin-film batteries, in association with superior cycling stability. Such microdevices allow for operations at ultrahigh rate up to 1,000 V s−1, three orders of magnitude higher than that of conventional supercapacitors. Micro-supercapacitors with an in-plane geometry have great promise for numerous miniaturized or flexible electronic applications. PMID:24042088

  11. Affective imagery and acceptance of replacing nuclear power plants.

    Science.gov (United States)

    Keller, Carmen; Visschers, Vivianne; Siegrist, Michael

    2012-03-01

    This study examined the relationship between the content of spontaneous associations with nuclear power plants and the acceptance of using new-generation nuclear power plants to replace old ones. The study also considered gender as a variable. A representative sample of the German- and French-speaking population of Switzerland (N= 1,221) was used. Log-linear models revealed significant two-way interactions between the association content and acceptance, association content and gender, and gender and acceptance. Correspondence analysis revealed that participants who were opposed to nuclear power plants mainly associated nuclear power plants with risk, negative feelings, accidents, radioactivity, waste disposal, military use, and negative consequences for health and environment; whereas participants favoring nuclear power plants mainly associated them with energy, appearance descriptions of nuclear power plants, and necessity. Thus, individuals opposing nuclear power plants had both more concrete and more diverse associations with them than people who were in favor of nuclear power plants. In addition, participants who were undecided often mentioned similar associations to those participants who were in favor. Males more often expressed associations with energy, waste disposal, and negative health effects. Females more often made associations with appearance descriptions, negative feelings, and negative environmental effects. The results further suggest that acceptance of replacing nuclear power plants was higher in the German-speaking part of the country, where all of the Swiss nuclear power plants are physically located. Practical implications for risk communication are discussed. © 2011 Society for Risk Analysis.

  12. Exposure to power frequency electromagnetic fields

    International Nuclear Information System (INIS)

    Skotte, J.

    1993-01-01

    The purpose was to asses personal exposure to power frequency electromagnetic fields in Denmark. Exposure to electrical and magnetic 50 Hz fields were measured with personal dosimeters in periods of 24 hours covering both occupational and residential environments. The study included both highly exposed and 'normal' exposed jobs. Measurements were carried out with dosimeters, which sample electrical and magnetic fields every 5 sec. Participants also wore the dosimeter during transportation. The dynamic range of the dosimeters was 0.01-200 μT and 0.6-10000 V/m. The highest average exposure in homes near high power lines was 2.24 μT. In most homes without nearby high power lines the average exposure was below 0.05 μT. Average values of '24-hour-dose' (μT times hours) for the generator facility, transmission line and substation workers were approximately the same as for the people living near high power lines (5 μT x hours). Electric field measurements with personal dosimeters involve several factors of uncertainty, as the body, posture, position of dosimeter etc. influence the results. The highest exposed groups were transmission line workers (GM: 44 V/m) and substation workers (GM: 23 V/m) but there were large variations (GSD: 4.7-4.8). In the work time the exposure level was the same for office workers and workers in the industry groups (GM: 12-13 V/m). In homes near high power lines (GM: 23 V/m) there was a non-significant tendency to higher exposure compared to homes without nearby high power lines. (AB) (11 refs.)

  13. A fully integrated, wide-load-range, high-power-conversion-efficiency switched capacitor DC-DC converter with adaptive bias comparator for ultra-low-power power management integrated circuit

    Science.gov (United States)

    Asano, Hiroki; Hirose, Tetsuya; Kojima, Yuta; Kuroki, Nobutaka; Numa, Masahiro

    2018-04-01

    In this paper, we present a wide-load-range switched-capacitor DC-DC buck converter with an adaptive bias comparator for ultra-low-power power management integrated circuit. The proposed converter is based on a conventional one and modified to operate in a wide load range by developing a load current monitor used in an adaptive bias comparator. Measurement results demonstrated that our proposed converter generates a 1.0 V output voltage from a 3.0 V input voltage at a load of up to 100 µA, which is 20 times higher than that of the conventional one. The power conversion efficiency was higher than 60% in the load range from 0.8 to 100 µA.

  14. Korean students' behavioral change toward nuclear power generation through education

    International Nuclear Information System (INIS)

    Han, Eun Ok; Kim, Jae Rok; Choi, Yoon Seok

    2014-01-01

    As a result of conducting a 45 minute-long seminar on the principles, state of use, advantages, and disadvantages of nuclear power generation for Korean elementary, middle, and high school students, the levels of perception including the necessity (p<0.017), safety (p<0.000), information acquisition (p<0.000), and subjective knowledge (p<0.000), objective knowledge (p<0.000), attitude (p<0.000), and behavior (p<0.000) were all significantly higher. This indicates that education can be effective in promoting widespread social acceptance of nuclear power and its continued use. In order to induce behavior change toward positive judgments on nuclear power generation, it is necessary to focus on attitude improvement while providing the information in all areas related to the perception, knowledge, attitude, and behavior. Here, the positive message on the convenience and the safety of nuclear power generation should be highlighted.

  15. Korean students' behavioral change toward nuclear power generation through education

    Energy Technology Data Exchange (ETDEWEB)

    Han, Eun Ok; Kim, Jae Rok; Choi, Yoon Seok [Dept. of Education and Research, Korea Academy of Nuclear Safety, Seoul (Korea, Republic of)

    2014-10-15

    As a result of conducting a 45 minute-long seminar on the principles, state of use, advantages, and disadvantages of nuclear power generation for Korean elementary, middle, and high school students, the levels of perception including the necessity (p<0.017), safety (p<0.000), information acquisition (p<0.000), and subjective knowledge (p<0.000), objective knowledge (p<0.000), attitude (p<0.000), and behavior (p<0.000) were all significantly higher. This indicates that education can be effective in promoting widespread social acceptance of nuclear power and its continued use. In order to induce behavior change toward positive judgments on nuclear power generation, it is necessary to focus on attitude improvement while providing the information in all areas related to the perception, knowledge, attitude, and behavior. Here, the positive message on the convenience and the safety of nuclear power generation should be highlighted.

  16. Analysis of the Potential for Use of Floating PV Power Plant on the Skadar Lake for Electricity Supply of Aluminium Plant in Montenegro

    Directory of Open Access Journals (Sweden)

    Vladan Durković

    2017-09-01

    Full Text Available This paper deals with a conceptual solution for the supply of a part of electrical energy for the needs of Aluminium Plant Podgorica (KAP in Montenegro from a large Floating Photovoltaic Power Plant (FPPP, that would be installed on the nearby lake. The recommended FPPP, with an innovative azimuth angle control method and total installed power of 90 MWp, would consist of 18 power plants having an installed power of 5 MWp each. An analysis using the NREL solar insolation database ascertained that the recommended FPPP power plant can achieve a significantly higher production in comparison with previous solutions. An economic analysis has shown that the recommended power plant would yield positive economic indicators. Additionally, such a power plant would significantly contribute to the reduction of CO2 emissions.

  17. Comparison of Power Versus Manual Injection in Bolus Shape and Image Quality on Contrast-Enhanced Magnetic Resonance Angiography: An Experimental Study in a Swine Model.

    Science.gov (United States)

    Tsuboyama, Takahiro; Jost, Gregor; Pietsch, Hubertus; Tomiyama, Noriyuki

    2017-09-01

    The aim of this study was to compare power versus manual injection in bolus shape and image quality on contrast-enhanced magnetic resonance angiography (CE-MRA). Three types of CE-MRA (head-neck 3-dimensional [3D] MRA with a test-bolus technique, thoracic-abdominal 3D MRA with a bolus-tracking technique, and thoracic-abdominal time-resolved 4-dimensional [4D] MRA) were performed after power and manual injection of gadobutrol (0.1 mmol/kg) at 2 mL/s in 12 pigs (6 sets of power and manual injections for each type of CE-MRA). For the quantitative analysis, the signal-to-noise ratio was measured on ascending aorta, descending aorta, brachiocephalic trunk, common carotid artery, and external carotid artery on the 6 sets of head-neck 3D MRA, and on ascending aorta, descending aorta, brachiocephalic trunk, abdominal aorta, celiac trunk, and renal artery on the 6 sets of thoracic-abdominal 3D MRA. Bolus shapes were evaluated on the 6 sets each of test-bolus scans and 4D MRA. For the qualitative analysis, arterial enhancement, superimposition of nontargeted enhancement, and overall image quality were evaluated on 3D MRA. Visibility of bolus transition was assessed on 4D MRA. Intraindividual comparison between power and manual injection was made by paired t test, Wilcoxon rank sum test, and analysis of variance by ranks. Signal-to-noise ratio on 3D MRA was statistically higher with power injection than with manual injection (P < 0.001). Bolus shapes (test-bolus, 4D MRA) were represented by a characteristic standard bolus curve (sharp first-pass peak followed by a gentle recirculation peak) in all the 12 scans with power injection, but only in 1 of the 12 scans with manual injection. Standard deviations of time-to-peak enhancement were smaller in power injection than in manual injection. Qualitatively, although both injection methods achieved diagnostic quality on 3D MRA, power injection exhibited significantly higher image quality than manual injection (P = 0.001) due to

  18. A study on boiling water reactor regional stability from the viewpoint of higher harmonics

    International Nuclear Information System (INIS)

    Takeuchi, Yutaka; Takigawa, Yukio; Uematsu, Hitoshi

    1994-01-01

    A quantitative study on a mechanism for boiling water reactor regional stability has been carried out from the viewpoint of higher harmonics. In the mechanism, the gain decrease in the void-to-power transfer function can be explained by the higher harmonics mode subcriticality. It is shown that the thermal-hydraulic feedback effect can compensate for the gain decrease, and regional oscillation can be sustained that way. For quantitative evaluations, a three-dimensional higher harmonics analysis model has been developed. The results show that the first azimuthal harmonics subcriticality has a relatively small value under a regionally unstable condition. Comparing the subcriticality and the steady-state power distribution, it is shown that the distribution exists whose first azimuthal harmonics subcriticality takes a small value. A method of decomposition for the oscillated power responses into the harmonics modes is presented. The results show that the corewide oscillation power response consists almost entirely of the fundamental mode, and the regional oscillation power response consists almost entirely of the first azimuthal harmonics mode. This indicates that regional oscillation is a phenomenon in which the first azimuthal harmonics mode oscillates on the basis of the fundamental mode

  19. Cyber Power

    Science.gov (United States)

    2010-05-01

    government. Another way of looking at power in the cyber domain is to consider the three faces or aspects of relational power. 1st Face: (A induces B do...power. For example, on the February 2010 anniversary of the Iranian Revolution, the government slowed the internet to prevent protesters sending films ...all but a few government controlled Web sites. The damage to business and tourism was significant, but the Chinese government was more concerned

  20. Significant determinants of academic performance by new students enrolled in the higher distance education system of Ecuador. The case of the Universidad Técnica Particular de Loja

    Directory of Open Access Journals (Sweden)

    Luis F. Moncada Mora

    2011-12-01

    Full Text Available In this article we present the significant determiners of academic performance of new students enrolled in the higher distance education system of Ecuador. A description and correlation of the variables were undertaken to formalize the probabilistic model that confirms the positive, negative, individual and global effects.

  1. Development of an accident sequence precursor methodology and its application to significant accident precursors

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Seung Hyun; Park, Sung Hyun; Jae, Moo Sung [Dept. of of Nuclear Engineering, Hanyang University, Seoul (Korea, Republic of)

    2017-03-15

    The systematic management of plant risk is crucial for enhancing the safety of nuclear power plants and for designing new nuclear power plants. Accident sequence precursor (ASP) analysis may be able to provide risk significance of operational experience by using probabilistic risk assessment to evaluate an operational event quantitatively in terms of its impact on core damage. In this study, an ASP methodology for two operation mode, full power and low power/shutdown operation, has been developed and applied to significant accident precursors that may occur during the operation of nuclear power plants. Two operational events, loss of feedwater and steam generator tube rupture, are identified as ASPs. Therefore, the ASP methodology developed in this study may contribute to identifying plant risk significance as well as to enhancing the safety of nuclear power plants by applying this methodology systematically.

  2. Computer-assisted quantitative assessment of power Doppler US: effects of microbubble contrast agent in the differentiation of breast tumors

    International Nuclear Information System (INIS)

    Kettenbach, Joachim; Helbich, Thomas H.; Huber, Sabine; Zuna, Ivan; Dock, Wolfgang

    2005-01-01

    Rationale and objectives: To objectively quantify the effects of a microbubble contrast agent to differentiate breast tumors with power doppler ultrasound and to compare these results with color doppler ultrasound (CD US). Methods: In 47 patients a microbubble contrast agent was injected intravenously. Computer-assisted quantitative assessment of the color pixel density was performed to evaluate the increase in Doppler signals. Results were compared to previously published results of a color Doppler ultrasound study. Results: Peak color pixel density at contrast-enhanced power Doppler ultrasound was higher for carcinomas than for benign tumors (P < 0.03). Time to peak enhancement was shorter in carcinomas than in benign tumors (P < 0.01). For both parameters, diagnostic accuracy of power Doppler ultrasound was 69 and 78%, and for color Doppler ultrasound 62 and 76%, respectively. Conclusions: Quantitative assessment of contrast-enhanced power Doppler ultrasound showed significant differences in malignant and benign breast tumors. Diagnostic accuracy of contrast-enhanced power Doppler ultrasound was higher compared to color Doppler ultrasound

  3. Risk perception among nuclear power plant personnel: A survey

    International Nuclear Information System (INIS)

    Kivimaeki, M.; Kalimo, R.

    1993-01-01

    This study investigated risk perception, well-being, and organizational commitment among nuclear power plant personnel. The study group, 428 employees from a nuclear power plant, completed a questionnaire which included the same questions as those in previous surveys on risk perception of lay persons and industrial workers. Hazards at work were not seen as a sizable problem by nuclear power plant personnel. The study group estimated the safety of nuclear power plants better and the possibility of a serious nuclear accident as more unlikely than the general public. Compared to employees in other industrial companies, the overall perceived risks at work among plant personnel did not exceed the respective perceptions of the reference groups. Risk-related attitudes did not explain well-being among plant personnel, but the relationship between the perceived probability of a serious nuclear accident at work and organizational commitment yielded to a significant correlation: Those plant workers who estimated the likelihood of an accident higher were less committed to the organization. 21 refs., 2 tabs

  4. Modernization of turbines in nuclear power plants

    International Nuclear Information System (INIS)

    Harig, T.

    2005-01-01

    An ongoing goal in the power generation industry is to maximize the output of currently installed assets. This is most important at nuclear power plants due to the large capital investments that went into these plants and their base loaded service demands. Recent trends in the United States show a majority of nuclear plants are either obtaining, or are in the process of obtaining NRC approvals for operating license extensions and power uprates. This trend is evident in other countries as well. For example, all Swedish nuclear power plants are currently working on projects to extend their service life and maximize capacity through thermal uprate and turbine-generator upgrade with newest technology. The replacement of key components with improved ones is a means of optimizing the service life and availability of power plants. Economic advantages result from increased efficiency, higher output, shorter startup and shutdown times as well as reduced outage times and service costs. The rapid advances over recent years in the development of calculation programs enables adaptation of the latest blading technology to the special requirements imposed by steam turbine upgrading. This results in significant potential for generating additional output with the implementation of new technology, even without increased thermal power. In contrast to maintenance and investment in pure replacement or repair of a component with the primary goal of maintaining operability and reliability, the additional output gained by upgrading enables a return on investment to be reaped. (orig.)

  5. Electrophysiological correlates of higher states of consciousness during sleep in long-term practitioners of the Transcendental Meditation program.

    Science.gov (United States)

    Mason, L I; Alexander, C N; Travis, F T; Marsh, G; Orme-Johnson, D W; Gackenbach, J; Mason, D C; Rainforth, M; Walton, K G

    1997-02-01

    Standard ambulatory night sleep electroencephalograph (EEG) of 11 long-term practitioners of the Transcendental Meditation (TM) program reporting "higher states of consciousness" during sleep (the experimental group) was compared to that of nine short-term practitioners and 11 non-practitioners. EEG tracings during stages 3 and 4 sleep showed the experimental group to have: 1) theta-alpha activity simultaneously with delta activity and 2) decreased chin electromyograph (EMG) during deep sleep (p = 0.002) compared to short-term practitioners. Spectral analysis fast Fourier transform (FFT) data of the first three cycles showed that: 3) the experimental subjects had significantly greater theta 2 (6-8 Hz)-alpha 1 (8-10 Hz) relative power during stages 3 and 4 than the combined control groups [t(30) = 5.5, p = 0.0000008] with no difference in time in delta; 4) there was a graded difference across groups during stages 3 and 4 in theta 2-alpha 1 power, with experimentals having greater power than short-term practitioners, who in turn had greater power than non-practitioners [t(30) = 5.08, p = 0.00002]; and 5) experimentals also had increased rapid eye movement (REM) density during REM periods compared to short-term practitioners (p = 0.04). Previous studies have found increased theta-alpha EEG activity during reported periods of "transcendental consciousness" during the TM technique. In the Vedic tradition, as described by Maharishi Mahesh Yogi, transcendental consciousness is the first of a sequence of higher states. The maintenance of transcendental consciousness along with deep sleep is said to be a distinctive criterion of further, stabilized higher states of consciousness. The findings of this study are interpreted as physiological support for this model.

  6. Impact of power uprate on environmental qualification of equipment in nuclear power plants

    International Nuclear Information System (INIS)

    Raheja, R.D.; Mohiuddin, A.; Alsammarae, A.

    1996-01-01

    Many nuclear power facilities are finding it economically beneficial to increase reactor output, from operating plants, by resorting to power uprates. A power uprate implies that a utility can increase the reactor output, or the megawatts generated, by increasing steam pressure without adding or changing any plant systems. This is perhaps one of the least expensive options for increasing the generating capacity of a power plant. However, a nuclear plant requires a comprehensive review of the plant systems, structures and components to assure their capability to withstand the resulting increased normal and accident plant conditions. A power uprate will typically result in a plant operating at higher than the originally designed environmental conditions. Safety related equipment in nuclear plants is presently qualified to the UFSAR Chapter 15 accident events and the resulting temperatures, pressures, radiation levels etc. These values will increase when the reactor is producing a higher MWe output. Components that are sensitive to the environment must be re-evaluated and assessed to determine their acceptability and operability under the revised environmental conditions. Most safety-related mechanical and electrical equipment will require an assessment from an environmental qualification standpoint. Utilities must perform this task in a systematic, auditable and cost effective manner to optimize their resources and minimize plant costs associated with modifications, replacements or equipment testing. This paper discusses various approaches and provides recommendations to achieve equipment qualification while satisfying the plant's objective of a power uprate

  7. Comparison of Battery-Powered and Manual Bone Biopsy Systems for Core Needle Biopsy of Sclerotic Bone Lesions.

    Science.gov (United States)

    Cohen, Micah G; McMahon, Colm J; Kung, Justin W; Wu, Jim S

    2016-05-01

    The purpose of this study was to compare manual and battery-powered bone biopsy systems for diagnostic yield and procedural factors during core needle biopsy of sclerotic bone lesions. A total of 155 consecutive CT-guided core needle biopsies of sclerotic bone lesions were performed at one institution from January 2006 to November 2014. Before March 2012, lesions were biopsied with manual bone drill systems. After March 2012, most biopsies were performed with a battery-powered system and either noncoaxial or coaxial biopsy needles. Diagnostic yield, crush artifact, CT procedure time, procedure radiation dose, conscious sedation dose, and complications were compared between the manual and battery-powered core needle biopsy systems by Fisher exact test and t test. One-way ANOVA was used for subgroup analysis of the two battery-powered systems for procedure time and radiation dose. The diagnostic yield for all sclerotic lesions was 60.0% (93/155) and was significantly higher with the battery-powered system (73.0% [27/37]) than with the manual systems (55.9% [66/118]) (p = 0.047). There was no significant difference between the two systems in terms of crush artifact, procedure time, radiation dose, conscious sedation administered, or complications. In subgroup analysis, the coaxial battery-powered biopsies had shorter procedure times (p = 0.01) and lower radiation doses (p = 0.002) than the coaxial manual systems, but the noncoaxial battery-powered biopsies had longer average procedure times and higher radiation doses than the coaxial manual systems. In biopsy of sclerotic bone lesions, use of a battery-powered bone drill system improves diagnostic yield over use of a manual system.

  8. Electric power development in the USSR

    International Nuclear Information System (INIS)

    Rudenko, Y.N.

    1993-01-01

    The generation of electric power in the USSR is based on the Unified Electric Power System (UEPS) whose network cover most of the habitable territory of the country. Therefore, the development of the UEPS governs the overall evolution of the electric power generation in the country. At present, eleven out of thirteen joint electric power systems, which supply electricity to most of the USSR, are operating within the UEPS. The total electric power generation in the country reached 1728 billion kWh in 1990, of which the UEPS supplied approximately 90%. About 70% of installed capacity of the UEPS is fossil-fuelled power plants, about 12 % is nuclear power plants, and about 18% is hydroelectric power plants. The system-forming grid of the UEPS is made up of transmission lines of 220, 330, 500 and 750 kV. The on-line supervisory control of the UEPS is achieved by four-level automated system of dispatch control (UEPS, joint electric power systems, regional electric power systems, electric power plants, substations,electric grid regions). The development and extension of the UEPS in the USSR ensure higher reliability and quality of electric power supply to end-users, combined with higher efficiency. The principal problem facing the UEPS are as follows: the need to ensure environmental protection and efficiency of the steam power plants; to improve the safety and efficiency of nuclear power plants. The solution to these problems will define the conditions of the UEPS development, as well as electric power systems of other countries, at least for the coming two decades. This paper characterizes the peculiarities of the UEPS development over the last 20 years, including the installed capacity structure and the system-forming electric power grid. Special attention is paid to the environmental problems related to functioning and development of the UEPS and to the means of their solution. (author)

  9. Power density effect on feasibility of water cooled thorium breeder reactor

    International Nuclear Information System (INIS)

    Sidik, Permana; Takaki, Naoyuki; Sekimoto, Hiroshi

    2008-01-01

    Breeding is made possible by the high value of neutron regeneration ratio η for 233 U in thermal energy region. The reactor is fueled by 233 U-Th oxide and it has used the light water as moderator. Some characteristics such as spectrum, η value, criticality, breeding performance and number density are evaluated. Several power densities are evaluated in order to analyze its effect to the breeding performance. The η value of fissile 233 U obtains higher value than 2 which may satisfy the breeding capability especially for thermal reactor for all investigated MFR. The increasing enrichment and decreasing conversion ratio are more significant for MFR 233 U enrichment. Number density of 233 Pa decreases significantly with decreasing power density which leads the reactor has better breeding performance because lower capture rate of 233 Pa. (author)

  10. Deregulated power prices: comparison of volatility

    International Nuclear Information System (INIS)

    Li Ying; Flynn, P.C.

    2004-01-01

    We examine electrical power price variability for 14 deregulated markets. Power price volatility is measured by price velocity, the daily average of the absolute value of price change per hour. Deregulated markets show a wide variability in price velocity. Some price velocity is expected and arises from the daily diurnal price pattern, which differs significantly between markets. Even when the expected daily variability in price is removed, the residual unexpected variability differs between markets. Some deregulated markets, most notably Britain and Spain, show patterns that are predictable and consistent and have low values of unexpected price velocity. These markets create a climate conducive to consumers facing the market through real time pricing and shaping consumption behaviors in response to price changes. Other markets, for example, South Australia and Alberta, have patterns that are inconsistent and irregular, and hence are hard for a customer to interpret; a customer in such a market will have a higher incentive to avoid demand side management and escape risk through hedging mechanisms

  11. Overview of Recent Grid Codes for PV Power Integration

    DEFF Research Database (Denmark)

    Craciun, Bogdan-Ionut; Kerekes, Tamas; Sera, Dezso

    2012-01-01

    The challenge to bring down the cost of produced photovoltaic (PV) power had a major impact on the PV market and in consequence the grid operators experienced higher and higher PV power penetration. The growing share of this decentralized generation plants started to affect the grid stability...

  12. Enabling Wind Power Nationwide

    Energy Technology Data Exchange (ETDEWEB)

    Jose Zayas, Michael Derby, Patrick Gilman and Shreyas Ananthan,

    2015-05-01

    Leveraging this experience, the U.S. Department of Energy’s (DOE’s) Wind and Water Power Technologies Office has evaluated the potential for wind power to generate electricity in all 50 states. This report analyzes and quantifies the geographic expansion that could be enabled by accessing higher above ground heights for wind turbines and considers the means by which this new potential could be responsibly developed.

  13. Power quality improvement of unbalanced power system with distributed generation units

    DEFF Research Database (Denmark)

    Hu, Y.; Chen, Zhe; Excell, P.

    2011-01-01

    This paper presents a power electronic system for improving the power quality of the unbalanced distributed generation units in three-phase four-wire system. In the system, small renewable power generation units, such as small PV generator, small wind turbines may be configured as single phase...... and control of the converter are described. Simulation results have demonstrated that the system can effectively correct the unbalance and enhance the system power quality....... generation units. The random nature of renewable power sources may result in significant unbalance in the power network and affect the power quality. An electronic converter system is proposed to correct the system unbalance and harmonics so as to deal with the power quality problems. The operation...

  14. From initial application to routine operation: Reviewing the Applications for Power Uprates

    International Nuclear Information System (INIS)

    Garis, Ninos; Skaanberg, Lars

    2007-01-01

    Current plans for power uprates in Swedish nuclear power plants will lead to significant increases in seven units and a lesser increase in one unit. To date SKI has received six applications, and two more are due in 2007. A power uprate process is initiated by the application to the Government by a licensee for approval to increase the thermal output of a reactor unit. This request is addressed to the Government and is forwarded to SKI for a preliminary safety review. The result of the review is then provided by SKI as a basis for a governmental decision. Six applications have been taken through the first stage of the process; of these, three have received governmental approval and three are currently awaiting a decision. If the licensee's application is approved by the Government, deeper analyses and studies are required in order to modify the plant and update the safety analysis report and the associated technical specifications. SKI reviews this material on a continuous basis prior to test and routine operation at the increased power level. There are four stages that require attention and review by SKI; 1. Review of the application to the Government for approval to operate at increased power levels, and preparation of a suitable answer. 2. Review and approval of the preliminary safety analysis report (PSAR) 3. Review and approval of the application for testing at the higher power level 4. Review and approval of routine operation at the higher power level. A thorough description of the handling of a power uprate process can be found in the SKI PM (SKI-PM 04:11) that is available on the SKI website (in Swedish)

  15. Wind power forecast

    Energy Technology Data Exchange (ETDEWEB)

    Pestana, Rui [Rede Electrica Nacional (REN), S.A., Lisboa (Portugal). Dept. Systems and Development System Operator; Trancoso, Ana Rosa; Delgado Domingos, Jose [Univ. Tecnica de Lisboa (Portugal). Seccao de Ambiente e Energia

    2012-07-01

    Accurate wind power forecast are needed to reduce integration costs in the electric grid caused by wind inherent variability. Currently, Portugal has a significant wind power penetration level and consequently the need to have reliable wind power forecasts at different temporal scales, including localized events such as ramps. This paper provides an overview of the methodologies used by REN to forecast wind power at national level, based on statistical and probabilistic combinations of NWP and measured data with the aim of improving accuracy of pure NWP. Results show that significant improvement can be achieved with statistical combination with persistence in the short-term and with probabilistic combination in the medium-term. NWP are also able to detect ramp events with 3 day notice to the operational planning. (orig.)

  16. The Role of English in Present Day Higher Education

    Directory of Open Access Journals (Sweden)

    Eman Abdulsalam AL-Khalil

    2017-10-01

    Full Text Available In today’s global world and with the help of modern technology, English has become the most common and dominant language spoken and used both at the national and international levels. It has been playing a major role in many sectors as medicine, engineering, politics, economics, international relations, and higher education in particular, the most important area where English is needed. It has also become a medium of instruction at universities in a large number of countries, a basic means of second language learning / teaching, an accessing source of modern knowledge and scientific research, and a means of global communication and earn living. It is realized nowadays at the level of Higher Education in many countries around the world, in addition to EU countries as Germany, Turkey, China, Republic of Korea, Malaysia, Indonesia, Japan, Australian, India …, the significance of providing education in English side by side with their natives. Hence, serious steps have taken to improve the quality of instruction in English at the administrative, academic, students’, publications and research levels. And in order to prove English language international power, it goes beyond its tertiary. Many English language proficiency, training and degree programs are managed not only inside but also abroad for internationalization of higher education to keep it up to date. However, this paper signifies the role of English in modern education, particularly in higher education sector and the role of modern technology in promoting English language learning / teaching quality to meet the standards, communication needs and cultural exchange across the world.

  17. FVEE research strategy for electrochemical power stores and electromobility; FVEE-Forschungsstrategie fuer elektrochemische Stromspeicher und Elektromobilitaet

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-04-28

    Research and development in the field of electric power storage has long been neglected in Germany. Great efforts will be required to make up for this. The main challenge is the fast development of low-cost stores with high energy density and power density as well as long life. For the next generation of electrochemical energy storage systems, more intensive research on materials and cell chemistry will be required in order to achieve significantly higher storage densities.

  18. Dimensionless Energy Conversion Characteristics of an Air-Powered Hydraulic Vehicle

    Directory of Open Access Journals (Sweden)

    Dongkai Shen

    2018-02-01

    Full Text Available Due to the advantages of resource conservation and less exhaust emissions, compressed air-powered vehicle has attracted more and more attention. To improve the power and efficiency of air-powered vehicle, an air-powered hydraulic vehicle was proposed. As the main part of the air-powered hydraulic vehicles, HP transformer (short for Hydropneumatic transformer is used to convert the pneumatic power to higher hydraulic power. In this study, to illustrate the energy conversion characteristics of air-powered hydraulic vehicle, dimensionless mathematical model of the vehicle’s working process was set up. Through experimental study on the vehicle, the dimensionless model was verified. Through simulation study on the vehicle, the following can be obtained: firstly, the increase of the hydraulic chamber orifice and the area ratio of the pistons can lead to a higher output power, while output pressure is just the opposite. Moreover, the increase of the output pressure and the aperture of the hydraulic chamber can lead to a higher efficiency, while area ratio of the pistons played the opposite role. This research can be referred to in the performance and design optimization of the HP transformers.

  19. Reference costs for power generation

    International Nuclear Information System (INIS)

    2003-12-01

    . Two hypotheses are considered in terms of CO 2 costs over the life span of the oil- and coal-fired power plants: 4 euro/t CO 2 and 20 euro/t CO 2 . The hypothesis of 4 euro/t CO 2 can be considered as very low - it will be significantly more expensive in 2015 and beyond (post-Kyoto period). The choice of a discount rate respectively lower or higher than the baseline hypothesis of 8% will increase, or decrease, the competitiveness of nuclear-based power production compared to fossil- fuel methods of power production because the investment load, which is higher for nuclear than for the other methods, decreases or, conversely, increases. The 8% discount rate adopted here was the rate used by the French Planning Office and is compatible with the profitability requirements currently noted in the electricity sector. The different variants do not bring into question the order of competitiveness of the production methods. 3. Plant operating on a half-time basis (less than 5000 hours/year): Considering the size of the initial investment, a nuclear power plant's competitiveness requires that it operate all year round. Should the nuclear power plant be operational for a shorter duration, then its competitiveness fades in favour of gas-fired power plants. More specifically, gas is more competitive than nuclear power (excluding externalities) for operating periods of less than 5000 hours. - 4. Plant operating on a minimum basis (less than 3000 hours/year): For short periods, the gas turbine is more competitive than the oil-fired turbine. The oil-fired turbine, however, is competitive for durations of less than 250 hours

  20. Natural gas power generation in Brazil: New window of opportunity?

    International Nuclear Information System (INIS)

    Gorini de Oliveira, Ricardo; Moraes Marreco, Juliana de

    2006-01-01

    This survey analyses the need as well as the attractiveness of private investment in natural gas thermal power generation under the Brazilian new power sector reform. Providing a scenario analysis from 2004 to 2014, this paper focuses on the investor perspective, and concludes that investments in natural gas thermal power plants in Brazil are not feasible, without financial subsidies stimulating investors. The more wary of risk both government and society are, and the more averse to risk the investor is, the higher the probability of higher capacity payment to provide incentives to investors. The alternative would be a lower capacity payment combined with higher thermal power tariffs; meaning that generators would receive much more payment when operating, despite assuming higher risks. Additionally, the improvement in safety supply cost is estimated and a sensibility analysis on the actual variables is performed

  1. Towards Integrated Pulse Detonation Propulsion and MHD Power

    Science.gov (United States)

    Litchford, Ron J.; Thompson, Bryan R.; Lineberry, John T.

    1999-01-01

    The interest in pulse detonation engines (PDE) arises primarily from the advantages that accrue from the significant combustion pressure rise that is developed in the detonation process. Conventional rocket engines, for example, must obtain all of their compression from the turbopumps, while the PDE provides additional compression in the combustor. Thus PDE's are expected to achieve higher I(sub sp) than conventional rocket engines and to require smaller turbopumps. The increase in I(sub sp) and the decrease in turbopump capacity must be traded off against each other. Additional advantages include the ability to vary thrust level by adjusting the firing rate rather than throttling the flow through injector elements. The common conclusion derived from these aggregated performance attributes is that PDEs should result in engines which are smaller, lower in cost, and lighter in weight than conventional engines. Unfortunately, the analysis of PDEs is highly complex due to their unsteady operation and non-ideal processes. Although the feasibility of the basic PDE concept has been proven in several experimental and theoretical efforts, the implied performance improvements have yet to be convincingly demonstrated. Also, there are certain developmental issues affecting the practical application of pulse detonation propulsion systems which are yet to be fully resolved. Practical detonation combustion engines, for example, require a repetitive cycle of charge induction, mixing, initiation/propagation of the detonation wave, and expulsion/scavenging of the combustion product gases. Clearly, the performance and power density of such a device depends upon the maximum rate at which this cycle can be successfully implemented. In addition, the electrical energy required for direct detonation initiation can be significant, and a means for direct electrical power production is needed to achieve self-sustained engine operation. This work addresses the technological issues associated

  2. On the Use of Energy Storage Technologies for Regulation Services in Electric Power Systems with Significant Penetration of Wind Energy

    DEFF Research Database (Denmark)

    Yang, Bo; Makarov, Yuri; Desteese, John

    2008-01-01

    Energy produced by intermittent renewable resources is sharply increasing in the United States. At high penetration levels, volatility of wind power production could cause additional problems for the power system balancing functions such as regulation. This paper reports some partial results...... and frequently changing regulation signal. Several energy storage options have been analyzed based on thirteen selection criteria. The evaluation process resulted in the selection of flywheels, pumped hydro electric power (or conventional hydro electric power) plant and sodium sulfur or nickel cadmium batteries...... of a project work, recently conducted by the Pacific Northwest National Laboratory (PNNL) for Bonneville Power Administration (BPA). The project proposes to mitigate additional intermittency with the help of Wide Area Energy Management System (WAEMS) that would provide a two-way simultaneous regulation service...

  3. Nuclear Power in Korea

    International Nuclear Information System (INIS)

    Ha, Duk-Sang

    2009-01-01

    Full text: Korea's nuclear power program has been promoted by step-by-step approach; the first stage was 1970's when it depended on the foreign contractors' technology and the second was 1980's when it accumulated lots of technology and experience by jointly implementing the project. Lastly in the third stage in 1990's, Korea successfully achieved the nuclear power technological self-reliance and developed its standard nuclear power plant, so-called Optimized Power Reactor 1000 (OPR 1000). Following the development of OPR 1000, Korea has continued to upgrade the design, known as the Advanced Power Reactor 1400 (APR 1400) and APR+. Korea is one of the countries which continuously developed the nuclear power plant projects during the last 30 years while the other advanced countries ceased the project, and therefore, significant reduction of project cost and construction schedule were possible which benefits from the repetition of construction project. And now, its nuclear industry infrastructure possesses the strong competitiveness in this field.The electricity produced from the nuclear power is 150,958 MWh in 2008, which covers approximately 36% of the total electricity demand in Korea, while the installed capacity of nuclear power is 17,716 MW which is 24% of the total installed capacity. We are currently operating 20 units of nuclear power plants in Korea, and also are constructing 8 additional units (9,600 MW). Korea's nuclear power plants have displayed their excellent operating performance; the average plant capacity factor was 93.4% in 2008, which are about 15% higher than the world average of 77.8%. Moreover, the number of unplanned trips per unit was only 0.35 in 2008, which is the world top class performance. Also currently we are operating four CANDU nuclear units in Korea which are the same reactor type and capacity as the Cernavoda Units. They have been showing the excellent operating performance, of which capacity in 2008 is 92.8%. All the Korean

  4. Disruptive Technologies in Higher Education

    Science.gov (United States)

    Flavin, Michael

    2012-01-01

    This paper analyses the role of "disruptive" innovative technologies in higher education. In this country and elsewhere, Higher Education Institutions (HEIs) have invested significant sums in learning technologies, with Virtual Learning Environments (VLEs) being more or less universal, but these technologies have not been universally…

  5. Linear matrix differential equations of higher-order and applications

    Directory of Open Access Journals (Sweden)

    Mustapha Rachidi

    2008-07-01

    Full Text Available In this article, we study linear differential equations of higher-order whose coefficients are square matrices. The combinatorial method for computing the matrix powers and exponential is adopted. New formulas representing auxiliary results are obtained. This allows us to prove properties of a large class of linear matrix differential equations of higher-order, in particular results of Apostol and Kolodner are recovered. Also illustrative examples and applications are presented.

  6. Deep tissue optical imaging of upconverting nanoparticles enabled by exploiting higher intrinsic quantum yield through use of millisecond single pulse excitation with high peak power

    DEFF Research Database (Denmark)

    Liu, Haichun; Xu, Can T.; Dumlupinar, Gökhan

    2013-01-01

    We have accomplished deep tissue optical imaging of upconverting nanoparticles at 800 nm, using millisecond single pulse excitation with high peak power. This is achieved by carefully choosing the pulse parameters, derived from time-resolved rate-equation analysis, which result in higher intrinsic...... quantum yield that is utilized by upconverting nanoparticles for generating this near infrared upconversion emission. The pulsed excitation approach thus promises previously unreachable imaging depths and shorter data acquisition times compared with continuous wave excitation, while simultaneously keeping...... therapy and remote activation of biomolecules in deep tissues....

  7. Protection of nuclear power plants against external events

    International Nuclear Information System (INIS)

    Suetterlin, L.

    1978-01-01

    The different aspects for the selection of external events to be accounted for in designing nuclear power plants and in defining load assumptions are illustrated: 1) In case of earthquake the severest possible events according to the state of science and technology are assumed. 2) For events where it is not or only to a certain extent possible to apply this method, e.g. in the load case airplane crash, load assumptions are defined in a combined probabilitic-deterministic way. By the example of plant protection, it is shown that by integrating all measures for protecting against interference of third parties (sabotage) or other external events, optimum protection concepts may be achieved. In all considerations on interference of third parties or other external events, one has to take into account that absolute protection is not possible. Nevertheless, it may be confirmed that nuclear power plants not only have a much higher level of protection than other, non-nuclear plants with equal or even higher potential hazard, but also that they meet the requirement not to increase significantly the current risk of society. (orig./HP) [de

  8. Comparisons of significant parameters for a standard 20% enriched and FLIP 70% enriched TRIGA core

    International Nuclear Information System (INIS)

    Ringle, John C.; Anderson, Terrance V.; Johnson, Arthur G.

    1978-01-01

    A comparison is made between the 20% and 70% enriched cores. The initial start-up data for both cores show the FLIP needs ∼3.8 times the 235 U mass as the 20% core just to go critical. Operational configurations for both cores indicate a need for ∼33% additional fuel above initial critical for adequate maneuvering excess. The fuel element worths are higher in the central core locations for the 20% elements while the peripheral element worths are about the same (with some thermal flux peaking in the FLIP perheral elements). Pulsing comparisons of the two cores show significant differences in reactivity insertions and power peaks. (author)

  9. Preliminary analysis of dry-steam geothermal power plant by employing exergy assessment: Case study in Kamojang geothermal power plant, Indonesia

    Directory of Open Access Journals (Sweden)

    Bayu Rudiyanto

    2017-09-01

    Full Text Available The objectives of this study are to perform the exergy analysis and ambient temperature optimization of the Kamojang geothermal power plant by employing Engineering Equation Solver (EES. The geothermal capacity is 55 MW and the field is vapor-dominated reservoir with temperature 245 °C. In the initial state temperature, pressure and mass flow data are collected from the plant operation. The study results show that system has overall efficiency of 35.86% which means that only 111,138.92 kW electrical power can be extracted from 309,000 kW thermal power being produced by 10 production wells of Kamojang. This low efficiency is due to irreversibility associated with different processes and components in the system. The largest irreversibility occurs in condenser due to which 53% of total energy is disposed into the environment. Ambient temperature at Kamojang varies from 17 to 20 °C. The effect of this variation in temperature is also investigated and it is observed that higher temperature does not have any significant impact on system efficiency.

  10. Nonsynchronous vibrations observed in a supercritical power transmission shaft

    Science.gov (United States)

    Darlow, M. S.; Zorzi, E. S.

    1979-01-01

    A flexible shaft is prone to a number of vibration phenomena which occur at frequencies other than synchronous with rotational speed. Nonsynchronous vibrations from several sources were observed while running a test rig designed to simulate the operation of a supercritical power transmission shaft. The test rig was run first with very light external damping and then with a higher level of external damping, for comparison. As a result, the effect of external damping on the nonsynchronous vibrations of the test rig was observed. All of these nonsynchronous vibrations were of significant amplitude. Their presence in the vibrations spectra for a supercritical power transmission shaft at various speeds in the operating range indicates that very careful attention to all of the vibration spectra should be made in any supercritical power transmission shafting. This paper presents a review of the analysis performed and a comparison with experimental data. A thorough discussion of the observed nonsynchronous whirl is also provided.

  11. CERN: Higher energies at LEP

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    This year will be the last that CERN's 27-kilometre LEP electron-positron collider will run routinely at around 45 GeV per beam. In the run, scheduled to begin in May, the four big experiments will top up their harvest so far of over 12 million Z particles for a final polishing of precision Z data. Behind the scenes, LEP is being prepared for higher energy running and a new phase of physics. After a brief technical stop in October, the aim is for a test run of up to 70 GeV per beam before the end of the year. Higher energy demands more radiofrequency power, which will be supplied by superconducting cavities. With this goal in mind, a programme of development work began at CERN over ten years ago, when LEP was still on the drawing board. Initially this effort focused on cavities made from sheet niobium, but later switched to copper covered by a sputtered niobium film, which gives better thermal and r.f. performance (September 1990, page 24). The first industrially-manufactured four-cavity niobium coated module, complete with its cryostat and r.f plumbing, was installed in LEP in 1993. Although it quickly achieved its nominal accelerating gradient of 6 MV/m, its reliability was affected by unforeseen problems in the associated power couplers. This delayed the installation schedule, but after a crash programme of design and modification of the power couplers, together with improvements in actual cavity design and manufacture, module supply and testing has now attained a satisfactory rhythm. Two modules installed in LEP amassed between them over 50 days of continuous running in 1994, and confidence is now high that the emphasis can shift towards integrating the cavities into LEP, rather than running the cavities themselves. During LEP's 1994-5 winter shutdown, modules are being installed at Points 2 and 6. Later, additional cavities will be installed in Points 2, 6 and 8 prior to embarking on the higher energy test run at the end of the year. After

  12. Aging of concrete components and its significance relative to life extension of nuclear power plants

    International Nuclear Information System (INIS)

    Naus, D.J.

    1987-01-01

    Nuclear power currently supplies about 16% of the US electricity requirements, with the percentage expected to rise to 20% by 1990. Despite the increasing role of nuclear power in energy production, cessation of orders for new nuclear plants in combination with expiration of operating licenses for several plants in the next 15 to 20 years results in a potential loss of electrical generating capacity of 50 to 60 gigawatts during the time period 2005 to 2020. A potential timely and cost-effective solution to the problem of meeting future energy demand is available through extension of the service life of existing nuclear plants. Any consideration of plant life extension, however, must consider the concrete components in these plants, since they play a vital safety role. Under the USNRC Nuclear Plant Aging Research (NPAR) Program, a study was conducted to review operating experience and to provide background that will lead to subsequent development of a methodology for assessing and predicting the effects of aging on the performance of concrete-based structures. The approach followed was in conformance with the NPAR strategy

  13. Numerical optimization for separation power of gas centrifuge

    International Nuclear Information System (INIS)

    Jiang Dongjun; Zeng Shi; Liu Bing

    2012-01-01

    In order to obtain higher separation power of the gas centrifuge, the code was developed to solve the flow-field of the counter-current to acquire the separation power, which was integrated with the iSight software, so a numerical optimization model for separation power was presented, in which the driver conditions and the geometry parameters of the waste baffle were optimized to get the maximum separation power using the sequential quadratic programming arithmetic, and the 12% higher results was acquired, which shows the feasibility of this method. The results also note that the separation power of gas centrifuge is sensitive to the driver conditions and the structure parameters of the waste baffle, so it is necessary to perform the optimization calculation for the certain gas centrifuge model. (authors)

  14. Analysis of Power Transfer Efficiency of Standard Integrated Circuit Immunity Test Methods

    Directory of Open Access Journals (Sweden)

    Hai Au Huynh

    2015-01-01

    Full Text Available Direct power injection (DPI and bulk current injection (BCI methods are defined in IEC 62132-3 and IEC 62132-4 as the electromagnetic immunity test method of integrated circuits (IC. The forward power measured at the RF noise generator when the IC malfunctions is used as the measure of immunity level of the IC. However, the actual power that causes failure in ICs is different from forward power measured at the noise source. Power transfer efficiency is used as a measure of power loss of the noise injection path. In this paper, the power transfer efficiencies of DPI and BCI methods are derived and validated experimentally with immunity test setup of a clock divider IC. Power transfer efficiency varies significantly over the frequency range as a function of the test method used and the IC input impedance. For the frequency range of 15 kHz to 1 GHz, power transfer efficiency of the BCI test was constantly higher than that of the DPI test. In the DPI test, power transfer efficiency is particularly low in the lower test frequency range up to 10 MHz. When performing the IC immunity tests following the standards, these characteristics of the test methods need to be considered.

  15. C.A.R. insurance and its significance in the construction of power plants

    International Nuclear Information System (INIS)

    Friedrich, J.

    1975-01-01

    The construction of a power lant entails a multitude of risks for the operator and for all parties participating in the construction. The progress of construction technology, reduced manufacturing times and new construction materials and methods result in greater risks. As a property insurance, C.A.R. insurance covers unforeseen destruction of or damage to the construction works from commencement of construction until handling over. It is thereby irrelevant whether such loss or damage falls to the burden of the principal or the contractors and craftsmen. In the event of loss or damage occurring, the search for those responsible is thus eliminated. Rectification of the loss or damage and continuation of the work is not delayed. (orig.) [de

  16. Dynamic Reactive Power Compensation of Large Scale Wind Integrated Power System

    DEFF Research Database (Denmark)

    Rather, Zakir Hussain; Chen, Zhe; Thøgersen, Paul

    2015-01-01

    wind turbines especially wind farms with additional grid support functionalities like dynamic support (e,g dynamic reactive power support etc.) and ii) refurbishment of existing conventional central power plants to synchronous condensers could be one of the efficient, reliable and cost effective option......Due to progressive displacement of conventional power plants by wind turbines, dynamic security of large scale wind integrated power systems gets significantly compromised. In this paper we first highlight the importance of dynamic reactive power support/voltage security in large scale wind...... integrated power systems with least presence of conventional power plants. Then we propose a mixed integer dynamic optimization based method for optimal dynamic reactive power allocation in large scale wind integrated power systems. One of the important aspects of the proposed methodology is that unlike...

  17. GPP Webinar: Solar Procurement Templates and Tools for Higher Education

    Science.gov (United States)

    Green Power Partnership webinar on solar procurement for Higher Education which features various tools and templates that schools can use to shape and manage the solar procurement process to a successful outcome.

  18. Polynomial regression analysis and significance test of the regression function

    International Nuclear Information System (INIS)

    Gao Zhengming; Zhao Juan; He Shengping

    2012-01-01

    In order to analyze the decay heating power of a certain radioactive isotope per kilogram with polynomial regression method, the paper firstly demonstrated the broad usage of polynomial function and deduced its parameters with ordinary least squares estimate. Then significance test method of polynomial regression function is derived considering the similarity between the polynomial regression model and the multivariable linear regression model. Finally, polynomial regression analysis and significance test of the polynomial function are done to the decay heating power of the iso tope per kilogram in accord with the authors' real work. (authors)

  19. Will cross-ownership reestablish market power in the Nordic power market?

    International Nuclear Information System (INIS)

    Amundsen, Eirik S.; Bergman, Lars

    2000-01-01

    The integration of the power markets in Norway and Sweden in 1996 significantly constrained the major power companies' ability to exercise market power within their national borders. In recent years, however, mergers and reciprocal acquisition of shares have reduced the number of independent players on the Norwegian-Swedish power market. The aim of this paper is to explore to what extent increasing cross-ownership among major power companies in Norway and Sweden might re-establish the market power that was lost when the two national power markets were integrated. The analysis is based on a numerical model, assuming Cournot quantity setting behaviour, of the Norwegian-Swedish power market. The simulation results suggest that partial ownership relations between major generators and other power-producing firms tend to increase horizontal market power and thus the market price of electricity. (author)

  20. Comparative funding consequences of large versus small gas-fired power generation units

    International Nuclear Information System (INIS)

    Johnson, N.G.

    1995-01-01

    Gas producers are increasingly looking to privately-owned gas-fired power generation as a major growth market to support the development of new fields being discovered across Australia. Gas-fired generating technology is more environmentally friendly than coal-fired power stations, has lower unit capital costs and has higher efficiency levels. With the recent downward trends in gas prices for power generation (especially in Western Australia) it is likely that gas will indeed be the consistently preferred fuel for generation in Australia. Gas producers should be sensitive to the different financial and risk characteristics of the potential market represented by large versus small gas-fired private power stations. These differences are exaggerated by the much sharper focus given by the private sector to quantify risk and to its allocation to the parties best able to manage it. The significant commercial differences between classes of generation projects result in gas producers themselves being exposed to diverging risk profiles through their gas supply contracts with generating companies. Selling gas to larger generation units results in gas suppliers accepting proportionately (i.e. not just prorata to the larger installed capacity) higher levels of financial risk. Risk arises from the higher probability of a project not being completed, from the increased size of penalty payments associated with non-delivery of gas and from the rising level of competition between gas suppliers. Gas producers must fully understand the economics and risks of their potential electricity customers and full financial analysis will materially help the gas supplier in subsequent commercial gas contract negotiations. (author). 1 photo

  1. The Atacama Cosmology Telescope: temperature and gravitational lensing power spectrum measurements from three seasons of data

    Energy Technology Data Exchange (ETDEWEB)

    Das, Sudeep [Argonne National Laboratory, 9700 S. Cass Ave., Lemont, IL 60439 (United States); Louis, Thibaut; Calabrese, Erminia; Dunkley, Joanna [Sub-department of Astrophysics, University of Oxford, Keble Road, Oxford, OX1 3RH (United Kingdom); Nolta, Michael R.; Bond, J Richard; Hajian, Amir; Hincks, Adam D. [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON, M5S 3H8 Canada (Canada); Addison, Graeme E.; Halpern, Mark [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, V6T 1Z4 Canada (Canada); Battistelli, Elia S. [Department of Physics, University of Rome ' ' La Sapienza' ' , Piazzale Aldo Moro 5, I-00185 Rome (Italy); Crichton, Devin; Gralla, Megan [Dept. of Physics and Astronomy, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218-2686 (United States); Devlin, Mark J.; Dicker, Simon [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA, 19104 (United States); Dünner, Rolando [Departamento de Astronomía y Astrofísica, Facultad de Física, Pontificía Universidad Católica, Casilla 306, Santiago 22 (Chile); Fowler, Joseph W. [NIST Quantum Devices Group, 325 Broadway Mailcode 817.03, Boulder, CO, 80305 (United States); Hasselfield, Matthew; Hlozek, Renée [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States); Hilton, Matt, E-mail: sudeepphys@gmail.com [Centre for Astronomy and Particle Theory, School of Physics and Astronomy, University of Nottingham, NG7 2RD (United Kingdom); and others

    2014-04-01

    We present the temperature power spectra of the cosmic microwave background (CMB) derived from the three seasons of data from the Atacama Cosmology Telescope (ACT) at 148 GHz and 218 GHz, as well as the cross-frequency spectrum between the two channels. We detect and correct for contamination due to the Galactic cirrus in our equatorial maps. We present the results of a number of tests for possible systematic error and conclude that any effects are not significant compared to the statistical errors we quote. Where they overlap, we cross-correlate the ACT and the South Pole Telescope (SPT) maps and show they are consistent. The measurements of higher-order peaks in the CMB power spectrum provide an additional test of the ΛCDM cosmological model, and help constrain extensions beyond the standard model. The small angular scale power spectrum also provides constraining power on the Sunyaev-Zel'dovich effects and extragalactic foregrounds. We also present a measurement of the CMB gravitational lensing convergence power spectrum at 4.6σ detection significance.

  2. The Atacama Cosmology Telescope: Temperature and Gravitational Lensing Power Spectrum Measurements from Three Seasons of Data

    Science.gov (United States)

    Das, Sudeep; Louis, Thibaut; Nolta, Michael R.; Addison, Graeme E.; Battisetti, Elia S.; Bond, J. Richard; Calabrese, Erminia; Crichton, Devin; Devlin, Mark J.; Dicker, Simon; hide

    2014-01-01

    We present the temperature power spectra of the cosmic microwave background (CMB) derived from the three seasons of data from the Atacama Cosmology Telescope (ACT) at 148 GHz and 218 GHz, as well as the cross-frequency spectrum between the two channels. We detect and correct for contamination due to the Galactic cirrus in our equatorial maps. We present the results of a number of tests for possible systematic error and conclude that any effects are not significant compared to the statistical errors we quote. Where they overlap, we cross-correlate the ACT and the South Pole Telescope (SPT) maps and show they are consistent. The measurements of higher-order peaks in the CMB power spectrum provide an additional test of the ?CDM cosmological model, and help constrain extensions beyond the standard model. The small angular scale power spectrum also provides constraining power on the Sunyaev-Zel'dovich effects and extragalactic foregrounds. We also present a measurement of the CMB gravitational lensing convergence power spectrum at 4.6s detection significance.

  3. The Atacama Cosmology Telescope: temperature and gravitational lensing power spectrum measurements from three seasons of data

    International Nuclear Information System (INIS)

    Das, Sudeep; Louis, Thibaut; Calabrese, Erminia; Dunkley, Joanna; Nolta, Michael R.; Bond, J Richard; Hajian, Amir; Hincks, Adam D.; Addison, Graeme E.; Halpern, Mark; Battistelli, Elia S.; Crichton, Devin; Gralla, Megan; Devlin, Mark J.; Dicker, Simon; Dünner, Rolando; Fowler, Joseph W.; Hasselfield, Matthew; Hlozek, Renée; Hilton, Matt

    2014-01-01

    We present the temperature power spectra of the cosmic microwave background (CMB) derived from the three seasons of data from the Atacama Cosmology Telescope (ACT) at 148 GHz and 218 GHz, as well as the cross-frequency spectrum between the two channels. We detect and correct for contamination due to the Galactic cirrus in our equatorial maps. We present the results of a number of tests for possible systematic error and conclude that any effects are not significant compared to the statistical errors we quote. Where they overlap, we cross-correlate the ACT and the South Pole Telescope (SPT) maps and show they are consistent. The measurements of higher-order peaks in the CMB power spectrum provide an additional test of the ΛCDM cosmological model, and help constrain extensions beyond the standard model. The small angular scale power spectrum also provides constraining power on the Sunyaev-Zel'dovich effects and extragalactic foregrounds. We also present a measurement of the CMB gravitational lensing convergence power spectrum at 4.6σ detection significance

  4. COHO - Utilizing Waste Heat and Carbon Dioxide at Power Plants for Water Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Sumanjeet [Porifera Inc., Hayward, CA (United States); Wilson, Aaron [Porifera Inc., Hayward, CA (United States); Wendt, Daniel [Porifera Inc., Hayward, CA (United States); Mendelssohn, Jeffrey [Porifera Inc., Hayward, CA (United States); Bakajin, Olgica [Porifera Inc., Hayward, CA (United States); Desormeaux, Erik [Porifera Inc., Hayward, CA (United States); Klare, Jennifer [Porifera Inc., Hayward, CA (United States)

    2017-07-25

    The COHO is a breakthrough water purification system that can concentrate challenging feed waters using carbon dioxide and low-grade heat. For this project, we studied feeds in a lab-scale system to simulate COHO’s potential to operate at coal- powered power plants. COHO proved successful at concentrating the highly scaling and challenging wastewaters derived from a power plant’s cooling towers and flue gas desulfurization units. We also found that COHO was successful at scrubbing carbon dioxide from flue gas mixtures. Thermal regeneration of the switchable polarity solvent forward osmosis draw solution ended up requiring higher temperatures than initially anticipated, but we also found that the draw solution could be polished via reverse osmosis. A techno-economic analysis indicates that installation of a COHO at a power plant for wastewater treatment would result in significant savings.

  5. An evaluation of possible next-generation high temperature molten-salt power towers.

    Energy Technology Data Exchange (ETDEWEB)

    Kolb, Gregory J.

    2011-12-01

    Since completion of the Solar Two molten-salt power tower demonstration in 1999, the solar industry has been developing initial commercial-scale projects that are 3 to 14 times larger. Like Solar Two, these initial plants will power subcritical steam-Rankine cycles using molten salt with a temperature of 565 C. The main question explored in this study is whether there is significant economic benefit to develop future molten-salt plants that operate at a higher receiver outlet temperature. Higher temperatures would allow the use of supercritical steam cycles that achieve an improved efficiency relative to today's subcritical cycle ({approx}50% versus {approx}42%). The levelized cost of electricity (LCOE) of a 565 C subcritical baseline plant was compared with possible future-generation plants that operate at 600 or 650 C. The analysis suggests that {approx}8% reduction in LCOE can be expected by raising salt temperature to 650 C. However, most of that benefit can be achieved by raising the temperature to only 600 C. Several other important insights regarding possible next-generation power towers were also drawn: (1) the evaluation of receiver-tube materials that are capable of higher fluxes and temperatures, (2) suggested plant reliability improvements based on a detailed evaluation of the Solar Two experience, and (3) a thorough evaluation of analysis uncertainties.

  6. The experience of power: examining the effects of power on approach and inhibition tendencies.

    Science.gov (United States)

    Anderson, Cameron; Jennifer, Berdahl L

    2002-12-01

    Two studies of task-focused dyads tested the approach/inhibition theory of power (D. Keltner, D. H. Gruenfeld, & C. Anderson, in press), which posits that having power increases the tendency to approach and decreases the tendency to inhibit. Results provided preliminary support for the theory: Participants higher in personality dominance or assigned control over resources expressed their true attitudes, experienced more positive and less negative emotion, were more likely to perceive rewards (i.e., that their partner liked them), and were less likely to perceive threats (e.g., that their partner felt anger toward them). Most of these effects were mediated by the sense of power, suggesting that subjective feelings of power are an important component in the effects of power.

  7. Domestic decision-making power, social support, and postpartum depression symptoms among immigrant and native women in Taiwan.

    Science.gov (United States)

    Chien, Li-Yin; Tai, Chen-Jei; Yeh, Mei-Chiang

    2012-01-01

    Domestic decision-making power is an integral part of women's empowerment. No study has linked domestic decision-making power and social support concurrently to postpartum depression and compared these between immigrant and native populations. The aim of this study was to examine domestic decision-making power and social support and their relationship to postpartum depressive symptoms among immigrant and native women in Taiwan. This cross-sectional survey included 190 immigrant and 190 native women who had delivered healthy babies during the past year in Taipei City. Depression was measured using the Edinburgh Postnatal Depression Scale, with a cutoff score of 10. Logistic regression was used to determine the factors associated with postpartum depression symptoms. Immigrant mothers had significantly higher prevalence of postpartum depression symptoms (41.1% vs. 8.4%) and had significantly lower levels of domestic decision-making power and social support than native mothers did. Logistic regression showed that insufficient family income was associated with an increased risk of postpartum depression symptoms, whereas social support and domestic decision-making power levels were associated negatively with postpartum depression symptoms. After accounting for these factors, immigrant women remained at higher risk of postpartum depression symptoms than native women did, odds ratio = 2.59, 95% CI [1.27, 5.28]. Domestic decision-making power and social support are independent protective factors for postpartum depression symptoms among immigrant and native women in Taiwan. Social support and empowerment interventions should be tested to discover whether they are able to prevent or alleviate postpartum depression symptoms, with special emphasis on immigrant mothers.

  8. Potential role of power authorities in offshore wind power development in the US

    International Nuclear Information System (INIS)

    Dhanju, Amardeep; Firestone, Jeremy; Kempton, Willett

    2011-01-01

    This article examines how power authorities could facilitate and manage offshore wind power development in US coastal waters. The power authority structure is an American 20th century institution for managing energy resources-a form of a public authority or public corporation dedicated to creating, operating and maintaining electric generation and transmission infrastructure. Offshore wind power is characterized by high capital costs but no fuel costs and thus low operating costs. Therefore a power authority, by virtue of its access to low-cost capital and managerial flexibility, could facilitate offshore wind power development by reducing financial risk of developing and lowering debt payments, thus improving the risk profile and lowering the cost of electricity production. Additionally, power authorities can be made up of multiple states, thus opening the possibility for joint action by neighboring coastal states. Using primary and secondary data, we undertake an in-depth analysis of the potential benefits and shortcomings of a power authority approach. - Highlights: → Proposes an institutional solution in the form of power authority for offshore wind power. → Power authority structure can significantly lower the cost of capital. → Tax-free bond financing available to power authority can significantly reduce the cost of energy. → It can enhance regional collaboration among coastal states to harness the offshore wind potential.

  9. Modeling particle emission and power flow in pulsed-power driven, nonuniform transmission lines

    Directory of Open Access Journals (Sweden)

    Nichelle Bruner

    2008-04-01

    Full Text Available Pulsed-power driven x-ray radiographic systems are being developed to operate at higher power in an effort to increase source brightness and penetration power. Essential to the design of these systems is a thorough understanding of electron power flow in the transmission line that couples the pulsed-power driver to the load. In this paper, analytic theory and fully relativistic particle-in-cell simulations are used to model power flow in several experimental transmission-line geometries fielded on Sandia National Laboratories’ upgraded Radiographic Integrated Test Stand [IEEE Trans. Plasma Sci. 28, 1653 (2000ITPSBD0093-381310.1109/27.901250]. Good agreement with measured electrical currents is demonstrated on a shot-by-shot basis for simulations which include detailed models accounting for space-charge-limited electron emission, surface heating, and stimulated particle emission. Resonant cavity modes related to the transmission-line impedance transitions are also shown to be excited by electron power flow. These modes can drive oscillations in the output power of the system, degrading radiographic resolution.

  10. With power comes responsibility: motorcycle engine power and power-to-weight ratio in relation to accident risk.

    Science.gov (United States)

    Mattsson, Markus; Summala, Heikki

    2010-02-01

    Current European legislation allows the EU member states to restrict the maximum power output of motorcycles to 74 kW even though evidence supporting the limit is scarce and has produced mixed results-perhaps because motorcycle performance has been measured by engine displacement, not engine power, in most of the previous studies. This study investigates the relationship of motorcycle engine power and power-to-weight ratio to risk of fatal and nonfatal crashes in Finland. The fatality rate (number of fatal accidents/number of registered motorbikes) for riders of different ages riding bikes belonging to different power and power-to-weight ratio classes was examined using a comprehensive in-depth database. Data on nonfatal accidents were acquired from a Web questionnaire (N = 2708), which also served as a basis for estimating riders' annual mileage. Mileage data allowed the calculation of accident risk per kilometer ridden for bikes differing in power and power-to-weight ratio. The fatality risk per number of registered motorcycles and per kilometer ridden increases both with power and power-to-weight ratio, independently of rider's age. No relationship between performance and risk of a less severe crash was found. The pre-accident speed of the most powerful bikes was 20 km/h or more over the speed limit in a large proportion of the fatal accidents (odds ratio = 4.8 for > 75 kW motorbikes; odds ratio = 6.2 for > 0.3 kW/kg motorbikes). The risk of being involved in a fatal crash is higher among the riders of powerful motorcycles. However, it is not clear whether the results are related to the riding habits of the riders that choose the most powerful bikes available or whether the high risk is due to the properties of the bikes themselves. Therefore, further research is needed before considering legal limits on motorcycle performance.

  11. Assessment of Power Potential of Tidal Currents and Impacts of Power Extraction on Flow Speeds in Indonesia

    Science.gov (United States)

    Orhan, K.; Mayerle, R.

    2016-12-01

    A methodology comprising of the estimates of power yield, evaluation of the effects of power extraction on flow conditions, and near-field investigations to deliver wake characteritics, recovery and interactions is described and applied to several straits in Indonesia. Site selection is done with high-resolution, three-dimensional flow models providing sufficient spatiotemporal coverage. Much attention has been given to the meteorological forcing, and conditions at the open sea boundaries to adequately capture the density gradients and flow fields. Model verification using tidal records shows excellent agreement. Sites with adequate depth for the energy conversion using horizontal axis tidal turbines, average kinetic power density greater than 0.5 kW/m2, and surface area larger than 0.5km2 are defined as energy hotspots. Spatial variation of the average extractable electric power is determined, and annual tidal energy resource is estimated for the straits in question. The results showed that the potential for tidal power generation in Indonesia is likely to exceed previous predictions reaching around 4,800MW. To assess the impact of the devices, flexible mesh models with higher resolutions have been developed. Effects on flow conditions, and near-field turbine wakes are resolved in greater detail with triangular horizontal grids. The energy is assumed to be removed uniformly by sub-grid scale arrays of turbines, and calculations are made based on velocities at the hub heights of the devices. An additional drag force resulting in dissipation of the pre-existing kinetic power from %10 to %60 within a flow cross-section is introduced to capture the impacts. It was found that the effect of power extraction on water levels and flow speeds in adjacent areas is not significant. Results show the effectivess of the method to capture wake characteritics and recovery reasonably well with low computational cost.

  12. Design of investment management optimization system for power grid companies under new electricity reform

    Science.gov (United States)

    Yang, Chunhui; Su, Zhixiong; Wang, Xin; Liu, Yang; Qi, Yongwei

    2017-03-01

    The new normalization of the economic situation and the implementation of a new round of electric power system reform put forward higher requirements to the daily operation of power grid companies. As an important day-to-day operation of power grid companies, investment management is directly related to the promotion of the company's operating efficiency and management level. In this context, the establishment of power grid company investment management optimization system will help to improve the level of investment management and control the company, which is of great significance for power gird companies to adapt to market environment changing as soon as possible and meet the policy environment requirements. Therefore, the purpose of this paper is to construct the investment management optimization system of power grid companies, which includes investment management system, investment process control system, investment structure optimization system, and investment project evaluation system and investment management information platform support system.

  13. Study on specifics of thermophysical properties of supercritical fluids in power engineering applications

    International Nuclear Information System (INIS)

    Mann, David; Pioro, Igor

    2015-01-01

    SuperCritical Pressures (SCPs) and SuperCritical Fluids (SFCs) are widely used in many industries worldwide. The largest application of SCPs is in the power industry in advanced coal-fired power plants. It is well-known that moving from subcritical-pressure power plants to SCP power plants increases gross thermal efficiency from 38-42% to about 50-55%. Despite all advances in thermal power-plants design and operation worldwide, they are still considered as not “environmentally friendly” due to significant carbon-dioxide emissions and air pollution as a result of the combustion process. In addition, coal-fired power-plants also produce virtual mountains of slag and ash, and other gas emissions that may contribute to acid rains. Therefore, the demand for clean, non-fossil-based electricity is growing. Due to this, nuclear power is considered as a basis for future electricity generation in the world. One of the major problems with current fleet of Nuclear Power Plants (NPPs) is their relatively low thermal efficiencies, especially, of water-cooled-reactor NPPs (the vast majority of NPPs) (30-36%), compared to those of advanced thermal power plants (55-62%). Based on that, next generation or Generation-IV reactors corresponding to those NPPs should definitely be more efficient. Higher level of thermal efficiencies can be reached only due to higher temperatures and, in some cases, higher pressures inside reactors and, especially, in power cycles of Generation-IV NPPs. Analysis of the six concepts of Generation-IV reactors and NPPs shows that three reactor concepts will use SCFs as reactor coolants (helium and water) and all concepts can be linked to SCFs as working fluids in power cycles (SC helium and /or carbon dioxide in the Brayton gas-turbine cycle, and SC water in the Rankine steam-turbine cycle). Therefore, the exact knowledge of specifics of thermophysical properties of SC helium, water and carbon dioxide is very important for any advances in these new

  14. Decolonizing Higher Education: Black Feminism and the Intersectionality of Race and Gender

    Directory of Open Access Journals (Sweden)

    Heidi Safia Mirza

    2015-05-01

    Full Text Available Drawing on black feminist theory, this paper examines the professional experiences of postcolonial diasporic black and ethnicized female academics in higher education. The paper explores the embodiment of gendered and racialized difference and reflects on the power of whiteness to shape everyday experiences in such places of privilege. The powerful yet hidden histories of women of color in higher education, such as the Indian women suffragettes and Cornelia Sorabji in late nineteenth century, are symbolic of the erasure of an ethnicized black feminist/womanist presence in mainstream (white educational establishments. The paper concludes that an understanding of black and ethnicized female agency and desire for education and learning is at the heart of a black feminist analysis that reclaims higher education as a radical site of resistance and refutation.

  15. Attractiveness of the underling: an automatic power --> sex association and its consequences for sexual harassment and aggression.

    Science.gov (United States)

    Bargh, J A; Raymond, P; Pryor, J B; Strack, F

    1995-05-01

    One characteristic of men who sexually harass is that they are not aware that their actions are inappropriate or a misuse of their power (L. F. Fitzgerald, 1993a). We investigated the existence and automaticity of a mental association between the concepts of power and sex, and its consequences for sexual harassment tendencies. Using a subliminal priming paradigm, Experiment 1 demonstrated an automatic link between power and sex, and only for men high in the likelihood to sexually harass or aggress. In Experiment 2, male participants were unobtrusively primed with either power-related or neutral stimuli. For men likely to sexually aggress, but not other participants, attraction ratings of a female confederate were significantly higher in the power priming than the neutral priming condition.

  16. Vehicle-to-Grid Power in Danish Electric Power Systems

    DEFF Research Database (Denmark)

    Pillai, Jayakrishnan Radhakrishna; Bak-Jensen, Birgitte

    2009-01-01

    The integration of renewable energy systems is often constrained by the variable nature of their output. This demands for the services of storing the electricity generated from most of the renewable energy sources. Vehicle-to-grid (V2G) power could use the inherent energy storage of electric...... vehicles and its quick response time to balance and stabilize a power system with fluctuating power. This paper outlines the use of battery electric vehicles in supporting large-scale integration of renewable energy in the Danish electric power systems. The reserve power requirements for a high renewable...... energy penetration could be met by an amount of V2G based electric vehicles less than 10% of the total vehicle need in Denmark. The participation of electric vehicle in ancillary services would earn significant revenues to the vehicle owner. The power balancing services of electric vehicles...

  17. Reliability and Energy Loss in Full-scale Wind Power Converter Considering Grid Codes and Wind Classes

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede; Franke, Toke

    2014-01-01

    With the increasing penetration of the wind power, reliable operation and cost-effective wind energy production are of more and more importance. As one of the promising configurations, the cost on reliability and production losses of permanent-magnet synchronous generator based full-scale wind......, if the specific designed wind turbine system operates at different wind classes, it can be seen that higher wind class level results in lower lifetime of the power converter. In respect to the cost of the reactive power, either the OE or the UE reactive power increases the energy loss per year significantly...... power converter is studied considering the grid code with reactive power production as well as the annual wind profile. Regarding the reliability, it is found that either the Over-Excited (OE) or the Under-Excited (UE) reactive power injection threatens the lifespan under all wind classes. Meanwhile...

  18. Velocity Drives Greater Power Observed During Back Squat Using Cluster Sets.

    Science.gov (United States)

    Oliver, Jonathan M; Kreutzer, Andreas; Jenke, Shane C; Phillips, Melody D; Mitchell, Joel B; Jones, Margaret T

    2016-01-01

    This investigation compared the kinetics and kinematics of cluster sets (CLU) and traditional sets (TRD) during back squat in trained (RT) and untrained (UT) men. Twenty-four participants (RT = 12, 25 ± 1 year, 179.1 ± 2.2 cm, 84.6 ± 2.1 kg; UT = 12, 25 ± 1 year, 180.1 ± 1.8 cm, 85.4 ± 3.8 kg) performed TRD (4 × 10, 120-second rest) and CLU (4 × (2 × 5) 30 seconds between clusters; 90 seconds between sets) with 70% one repetition maximum, randomly. Kinematics and kinetics were sampled through force plate and linear position transducers. Resistance-trained produced greater overall force, velocity, and power; however, similar patterns were observed in all variables when comparing conditions. Cluster sets produced significantly greater force in isolated repetitions in sets 1-3, while consistently producing greater force due to a required reduction in load during set 4 resulting in greater total volume load (CLU, 3302.4 ± 102.7 kg; TRD, 3274.8 ± 102.8 kg). Velocity loss was lessened in CLU resulting in significantly higher velocities in sets 2 through 4. Furthermore, higher velocities were produced by CLU during later repetitions of each set. Cluster sets produced greater power output for an increasing number of repetitions in each set (set 1, 5 repetitions; sets 2 and 3, 6 repetitions; set 4, 8 repetitions), and the difference between conditions increased over subsequent sets. Time under tension increased over each set and was greater in TRD. This study demonstrates greater power output is driven by greater velocity when back squatting during CLU; therefore, velocity may be a useful measure by which to assess power.

  19. Safety significance of ATR passive safety response attributes

    International Nuclear Information System (INIS)

    Atkinson, S.A.

    1990-01-01

    The Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory was designed with some passive safety response attributes which contribute to the safety of the facility. The three passive safety attributes being evaluated in the paper are: 1) In-core and in-vessel natural convection cooling, 2) a passive heat sink capability of the ATR primary coolant system (PCS) for the transfer of decay power from the uninsulated piping to the confinement, and 3) gravity feed of emergency coolant makeup. The safety significance of the ATR passive safety response attributes is that the reactor can passively respond to most transients, given a reactor scram, to provide adequate decay power removal and a significant time for operator action should the normal active heat removal systems and their backup systems both fail. The ATR Interim Level 1 Probabilistic Risk Assessment (PRA) models and results were used to evaluate the significance to ATR fuel damage frequency (or probability) of the above three passive response attributes. The results of the evaluation indicate that the first attribute is a major safety characteristic of the ATR. The second attribute has a noticeable but only minor safety significance. The third attribute has no significant influence on the ATR firewater injection system (emergency coolant system)

  20. Higher harmonics generation in relativistic electron beam with virtual cathode

    Energy Technology Data Exchange (ETDEWEB)

    Kurkin, S. A., E-mail: KurkinSA@gmail.com; Badarin, A. A.; Koronovskii, A. A.; Hramov, A. E. [Saratov State Technical University, Politechnicheskaja 77, Saratov 410028, Russia and Saratov State University, Astrakhanskaja 83, Saratov 410012 (Russian Federation)

    2014-09-15

    The study of the microwave generation regimes with intense higher harmonics taking place in a high-power vircator consisting of a relativistic electron beam with a virtual cathode has been made. The characteristics of these regimes, in particular, the typical spectra and their variations with the change of the system parameters (beam current, the induction of external magnetic field) as well as physical processes occurring in the system have been analyzed by means of 3D electromagnetic simulation. It has been shown that the system under study demonstrates the tendency to the sufficient growth of the amplitudes of higher harmonics in the spectrum of current oscillations in the VC region with the increase of beam current. The obtained results allow us to consider virtual cathode oscillators as promising high power mmw-to-THz sources.

  1. Internationalization, Regionalization, and Soft Power: China's Relations with ASEAN Member Countries in Higher Education

    Science.gov (United States)

    Yang, Rui

    2012-01-01

    Since the late 1980s, there has been a resurgence of regionalism in world politics. Prospects for new alliances are opened up often on a regional basis. In East and Southeast Asia, regionalization is becoming evident in higher education, with both awareness and signs of a rising ASEAN+3 higher education community. The quest for regional influence…

  2. Maximal locality and predictive power in higher-dimensional, compactified field theories

    International Nuclear Information System (INIS)

    Kubo, Jisuke; Nunami, Masanori

    2004-01-01

    To realize maximal locality in a trivial field theory, we maximize the ultraviolet cutoff of the theory by fine tuning the infrared values of the parameters. This optimization procedure is applied to the scalar theory in D + 1 dimensional (D ≥ 4) with one extra dimension compactified on a circle of radius R. The optimized, infrared values of the parameters are then compared with the corresponding ones of the uncompactified theory in D dimensions, which is assumed to be the low-energy effective theory. We find that these values approximately agree with each other as long as R -1 > approx sM is satisfied, where s ≅ 10, 50, 50, 100 for D = 4,5,6,7, and M is a typical scale of the D-dimensional theory. This result supports the previously made claim that the maximization of the ultraviolet cutoff in a nonrenormalizable field theory can give the theory more predictive power. (author)

  3. Efficient coding schemes with power allocation using space-time-frequency spreading

    Institute of Scientific and Technical Information of China (English)

    Jiang Haining; Luo Hanwen; Tian Jifeng; Song Wentao; Liu Xingzhao

    2006-01-01

    An efficient space-time-frequency (STF) coding strategy for multi-input multi-output orthogonal frequency division multiplexing (MIMO-OFDM) systems is presented for high bit rate data transmission over frequency selective fading channels. The proposed scheme is a new approach to space-time-frequency coded OFDM (COFDM) that combines OFDM with space-time coding, linear precoding and adaptive power allocation to provide higher quality of transmission in terms of the bit error rate performance and power efficiency. In addition to exploiting the maximum diversity gain in frequency, time and space, the proposed scheme enjoys high coding advantages and low-complexity decoding. The significant performance improvement of our design is confirmed by corroborating numerical simulations.

  4. Coal-fired Power Plants with Flexible Amine-based CCS and Co-located Wind Power: Environmental, Economic and Reliability Outcomes

    Science.gov (United States)

    Bandyopadhyay, Rubenka

    Carbon Capture and Storage (CCS) technologies provide a means to significantly reduce carbon emissions from the existing fleet of fossil-fired plants, and hence can facilitate a gradual transition from conventional to more sustainable sources of electric power. This is especially relevant for coal plants that have a CO2 emission rate that is roughly two times higher than that of natural gas plants. Of the different kinds of CCS technology available, post-combustion amine based CCS is the best developed and hence more suitable for retrofitting an existing coal plant. The high costs from operating CCS could be reduced by enabling flexible operation through amine storage or allowing partial capture of CO2 during high electricity prices. This flexibility is also found to improve the power plant's ramp capability, enabling it to offset the intermittency of renewable power sources. This thesis proposes a solution to problems associated with two promising technologies for decarbonizing the electric power system: the high costs of the energy penalty of CCS, and the intermittency and non-dispatchability of wind power. It explores the economic and technical feasibility of a hybrid system consisting of a coal plant retrofitted with a post-combustion-amine based CCS system equipped with the option to perform partial capture or amine storage, and a co-located wind farm. A techno-economic assessment of the performance of the hybrid system is carried out both from the perspective of the stakeholders (utility owners, investors, etc.) as well as that of the power system operator. (Abstract shortened by ProQuest.).

  5. Attitudes of the general public and electric power company employees toward nuclear power generation

    International Nuclear Information System (INIS)

    Komiyama, Hisashi

    1997-01-01

    We conducted an awareness survey targeted at members of the general public residing in urban areas and in areas scheduled for construction of nuclear power plants as well as employees of electric power company in order to determine the awareness and attitude structures of people residing near scheduled construction sites of nuclear power plants with respect to nuclear power generation, and to examine ways of making improvements in terms of promoting nuclear power plant construction sites. Analysis of those results revealed that there are no significant differences in the awareness and attitudes of people residing in urban areas and in areas near scheduled construction sites. On the contrary, a general sense of apprehension regarding the construction of nuclear power plants was observed common to both groups. In addition, significant differences in awareness and attitudes with respect to various factors were determined to exist between members of the general public residing in urban areas and scheduled construction sites and employees of electric power company. (author)

  6. Performance evaluation of a high power DC-DC boost converter for PV applications using SiC power devices

    Science.gov (United States)

    Almasoudi, Fahad M.; Alatawi, Khaled S.; Matin, Mohammad

    2016-09-01

    The development of Wide band gap (WBG) power devices has been attracted by many commercial companies to be available in the market because of their enormous advantages over the traditional Si power devices. An example of WBG material is SiC, which offers a number of advantages over Si material. For example, SiC has the ability of blocking higher voltages, reducing switching and conduction losses and supports high switching frequency. Consequently, SiC power devices have become the affordable choice for high frequency and power application. The goal of this paper is to study the performance of 4.5 kW, 200 kHz, 600V DC-DC boost converter operating in continuous conduction mode (CCM) for PV applications. The switching behavior and turn on and turn off losses of different switching power devices such as SiC MOSFET, SiC normally ON JFET and Si MOSFET are investigated and analyzed. Moreover, a detailed comparison is provided to show the overall efficiency of the DC-DC boost converter with different switching power devices. It is found that the efficiency of SiC power switching devices are higher than the efficiency of Si-based switching devices due to low switching and conduction losses when operating at high frequencies. According to the result, the performance of SiC switching power devices dominate the conventional Si power devices in terms of low losses, high efficiency and high power density. Accordingly, SiC power switching devices are more appropriate for PV applications where a converter of smaller size with high efficiency, and cost effective is required.

  7. The ratio of nurse consultation and physician efficiency index of senior rheumatologists is significantly higher than junior physicians in rheumatology residency training

    DEFF Research Database (Denmark)

    Emamifar, Amir; van Bui Hansen, Morten Hai; Jensen Hansen, Inger Marie

    2017-01-01

    To elucidate the difference between ratios of nurse consultation sought by senior rheumatologists and junior physicians in rheumatology residency training, and also to evaluate physician efficiency index respecting patients with rheumatoid arthritis (RA). Data regarding outpatient visits for RA...... patients between November 2013 and 2015 were extracted. The mean interval (day) between consultations, the nurse/physician visits ratio, and physician efficiency index (nurse/physician visits ratio × mean interval) for each senior and junior physicians were calculated. Disease Activity Score in 28 joints....../physician visits ratio (P = .01) and mean efficiency index (P = .04) of senior rheumatologists were significantly higher than that of junior physicians. Regression analysis showed a positive correlation between physician postgraduate experience and physician efficiency index adjusted for DAS28 at baseline...

  8. Development of Integrated Assessment System for Underground Power Cable Performance: A Case Study

    Science.gov (United States)

    Turan, Faiz Mohd; Johan, Kartina; Soliha Sahimi, Nur; Nor, Nik Hisyamudin Muhd

    2017-08-01

    The basic operation of any electrical machines that is catered to serve needs of civilization involves electrical power which is the main source to trigger the internal mechanism in the machines then transfer the power to other form of energy such as mechanical, light, sound and etc. The supplies of electrical does not happen just by providing the source itself, it has load carrying agent which in many cases, user would refer to it as cable. Specifically, it is the power cable which its ampacity depends significantly on the operation temperature and load stress on it. Apart from having to focus on providing improvement on improving efficiency on the source itself, power cable plays and important role because without it, current ranging from low to high could not be transmitted and hence a failure of the power system generally. Studies have conducted to discuss whether which factor contributes relatively more to the causes of power cable failure or breakdown. Such factors can be narrowed down to the three major causes which are over temperature, over voltage and stress caused by over current. Over current is one of the factor which is depends on the usage of the power system itself. The higher the usage of the power system, higher the chances of over current to take place. This will then produce load stress on the cable which eventually destroy the insulator of the cable and slowly reach the core of the cable. It is believed that an assessment method should be implemented in order to predict the performance and failure rate of the power cable and use this prediction as reference rather than just letting power failure to happen anytime unpredictable which cause huge inconvenience to users and industries. Not only do a method should be implemented, it should be as easy to be used and understood by large range of users and integrated by a graphical user interface to be used. Therefore, this research will further narrow down on the approaches to do so and the location

  9. More Stake, Less Gravy? Issues of Knowledge and Power in Higher Education.

    Science.gov (United States)

    Bak, Nelleke; Paterson, Andrew

    1997-01-01

    Two perspectives on higher education's stakeholders and their involvement in the development of knowledge in universities are examined and contrasted: (1) that the "stakeholder" notion of knowledge doesn't allow for critical engagement with knowledge, and (2) that the "stakeholder" view of knowledge acknowledges clear links between knowledge and…

  10. Optimal Capacitor Bank Capacity and Placement in Distribution Systems with High Distributed Solar Power Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, Brian S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Mather, Barry A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Cho, Gyu-Jung [Sungkyunkwan University, Korea; Oh, Yun-Sik [Sungkyunkwan University, Korea; Kim, Min-Sung [Sungkyunkwan University, Korea; Kim, Ji-Soo [Sungkyunkwan University, Korea; Kim, Chul-Hwan [Sungkyunkwan University, Korea

    2018-02-01

    Capacitor banks have been generally installed and utilized to support distribution voltage during period of higher load or on longer, higher impedance, feeders. Installations of distributed energy resources in distribution systems are rapidly increasing, and many of these generation resources have variable and uncertain power output. These generators can significantly change the voltage profile across a feeder, and therefore when a new capacitor bank is needed analysis of optimal capacity and location of the capacitor bank is required. In this paper, we model a particular distribution system including essential equipment. An optimization method is adopted to determine the best capacity and location sets of the newly installed capacitor banks, in the presence of distributed solar power generation. Finally we analyze the optimal capacitor banks configuration through the optimization and simulation results.

  11. Load-Following Voltage Controller Design for a Static Space Nuclear Power System

    International Nuclear Information System (INIS)

    Parlos, Alexander G.; Onbasioglou, Fetiye O.; Metzger, John D.

    2000-01-01

    The reliability of static space nuclear power systems (SNPSs) could be improved through the use of backup devices in addition to shunt regulators, as currently proposed for load following. Shunt regulator failure leading to reactor shutdown is possible, as is the possible need to deliver somewhat higher power level to the load than originally expected. A backup system is proposed in SNPSs to eliminate the possibility of a single-point failure in the shunt regulators and to increase the overall system power delivery capability despite changing mission needs and component characteristics. The objective of this paper is to demonstrate the feasibility of such a backup device for voltage regulation in static SNPSs that is capable of overcoming system variations resulting from operation at different power levels. A dynamic compensator is designed using the Linear Quadratic Gaussian with Loop Transfer Recovery method. The resulting compensators are gain scheduled using the SNPS electric power as the scheduling variable, resulting in a nonlinear compensator. The performance of the gain-scheduled compensator is investigated extensively using an SNPS simulator. The simulations demonstrate the effects of the fuel temperature reactivity coefficient variations on the load-following capabilities of the SNPS. Robustness analysis results demonstrate that the proposed controller exhibits significant operational flexibility, and it can be considered for long-term space mission requiring significant levels of autonomy

  12. LNG plant combined with power plant

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, I; Kikkawa, Y [Chiyoda Chemical Engineering and Construction Co. Ltd., Tokyo (Japan)

    1997-06-01

    The LNG plant consumers a lot of power of natural gas cooling and liquefaction. In some LNG plant location, a rapid growth of electric power demand is expected due to the modernization of area and/or the country. The electric power demand will have a peak in day time and low consumption in night time, while the power demand of the LNG plant is almost constant due to its nature. Combining the LNG plant with power plant will contribute an improvement the thermal efficiency of the power plant by keeping higher average load of the power plant, which will lead to a reduction of electrical power generation cost. The sweet fuel gas to the power plant can be extracted from the LNG plant, which will be favorable from view point of clean air of the area. (Author). 5 figs.

  13. LNG plant combined with power plant

    International Nuclear Information System (INIS)

    Aoki, I.; Kikkawa, Y.

    1997-01-01

    The LNG plant consumers a lot of power of natural gas cooling and liquefaction. In some LNG plant location, a rapid growth of electric power demand is expected due to the modernization of area and/or the country. The electric power demand will have a peak in day time and low consumption in night time, while the power demand of the LNG plant is almost constant due to its nature. Combining the LNG plant with power plant will contribute an improvement the thermal efficiency of the power plant by keeping higher average load of the power plant, which will lead to a reduction of electrical power generation cost. The sweet fuel gas to the power plant can be extracted from the LNG plant, which will be favorable from view point of clean air of the area. (Author). 5 figs

  14. Fusion-power demonstration

    International Nuclear Information System (INIS)

    Henning, C.D.; Logan, B.G.; Carlson, G.A.; Neef, W.S.; Moir, R.W.; Campbell, R.B.; Botwin, R.; Clarkson, I.R.; Carpenter, T.J.

    1983-01-01

    As a satellite to the MARS (Mirror Advanced Reactor Study) a smaller, near-term device has been scoped, called the FPD (Fusion Power Demonstration). Envisioned as the next logical step toward a power reactor, it would advance the mirror fusion program beyond MFTF-B and provide an intermediate step toward commercial fusion power. Breakeven net electric power capability would be the goal such that no net utility power would be required to sustain the operation. A phased implementation is envisioned, with a deuterium checkout first to verify the plasma systems before significant neutron activation has occurred. Major tritium-related facilities would be installed with the second phase to produce sufficient fusion power to supply the recirculating power to maintain the neutral beams, ECRH, magnets and other auxiliary equipment

  15. Fusion power demonstration

    International Nuclear Information System (INIS)

    Henning, C.D.; Logan, B.G.

    1983-01-01

    As a satellite to the MARS (Mirror Advanced Reactor Study) a smaller, near-term device has been scoped, called the FPD (Fusion Power Demonstration). Envisioned as the next logical step toward a power reactor, it would advance the mirror fusion program beyond MFTF-B and provide an intermediate step toward commercial fusion power. Breakeven net electric power capability would be the goal such that no net utility power would be required to sustain the operation. A phased implementation is envisioned, with a deuterium checkout first to verify the plasma systems before significant neutron activation has occurred. Major tritium-related facilities would be installed with the second phase to produce sufficient fusion power to supply the recirculating power to maintain the neutral beams, ECRH, magnets and other auxiliary equipment

  16. Nuclear power economics

    International Nuclear Information System (INIS)

    Moynet, G.

    1987-01-01

    The economical comparison of nuclear power plants with coal-fired plants in some countries or areas are analyzed. It is not difficult to show that nuclear power will have a significant and expanding role to play in providing economic electricity in the coming decades. (Liu)

  17. LEADERSHIP POWER PERCEPTION OF AMATEUR AND PROFESSIONAL SOCCER COACHES ACCORDING TO THEIR MARITAL STATUS

    Directory of Open Access Journals (Sweden)

    E. Konter

    2011-11-01

    Full Text Available The purpose of this study was to analyse the leadership power perception of amateur and professional soccer coaches according to their marital status. Data were collected from 165 male soccer coaches (n=71 technical director-manager and A license, n=46 B license, n=48 amateur license. An adapted Turkish version of Power in Soccer Questionnaire-Self (PSQ-S for coaches and an information form were used for the data collection [21]. Cronbach reliability alphas of PSQ-S range between 0.65 and 0.84. Coaches’ data were analysed by Kruskal-Wallis and Mann-Whitney tests. Kruskal-Wallis analysis of PSQ-S revealed significant differences between leadership power perception of amateur and professional soccer coaches according to their marital status related to Referent Power (RP [χ[sup]2[/sup] (3 = 9.61, p0.05. The results indicated that married coaches have higher perception of RP than single coaches, irrespective of being an amateur or a professional. Comparison of professional and amateur coaches suggests that while single professional coaches have higher perception of EP than married professional coaches, the results are the reverse for amateur coaches; in other words, amateur married coaches have higher perception of EP than amateur single coaches. There is a lack of research to draw more certain conclusions. Future researchers should also take into consideration personality, psychological skills, sport experience, age, taking responsibility, attributions, expectations, emotions, perception of achievement, etc.

  18. A Comparison of a Solar Power Satellite Concept to a Concentrating Solar Power System

    Science.gov (United States)

    Smitherman, David V.

    2013-01-01

    A comparison is made of a solar power satellite (SPS) concept in geostationary Earth orbit to a concentrating solar power (CSP) system on the ground to analyze overall efficiencies of each infrastructure from solar radiance at 1 AU to conversion and transmission of electrical energy into the power grid on the Earth's surface. Each system is sized for a 1-gigawatt output to the power grid and then further analyzed to determine primary collector infrastructure areas. Findings indicate that even though the SPS concept has a higher end-to-end efficiency, the combined space and ground collector infrastructure is still about the same size as a comparable CSP system on the ground.

  19. A Review of Power Electronics Based Microgrids

    DEFF Research Database (Denmark)

    Wang, Xiongfei; Guerrero, Josep M.; Blaabjerg, Frede

    2012-01-01

    The increased penetration of Distributed Energy Resources (DER) is challenging the entire architecture of conventional electrical power system. Microgrid paradigm, featuring higher flexibility and reliability, becomes an attractive candidate for the future power grid. In this paper, an overview o...

  20. New power generation technology options under the greenhouse gases mitigation scenario in China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qiang [Graduate University of Chinese Academy of Science, 19A Yu Quan Road, Beijing 100049 (China); Energy Research Institute, Guohong Mansion, Xicheng District, Beijing 100038 (China); Shi, Minjun [Graduate University of Chinese Academy of Science, 19A Yu Quan Road, Beijing 100049 (China); Jiang, Kejun [Energy Research Institute, Guohong Mansion, Xicheng District, Beijing 100038 (China)

    2009-06-15

    Climate change has become a global issue. Almost all countries, including China, are now considering adopting policies and measures to reduce greenhouse gas (GHG) emissions. The power generation sector, as a key source of GHG emissions, will also have significant potential for GHG mitigation. One of the key options is to use new energy technologies with higher energy efficiencies and lower carbon emissions. In this article, we use an energy technology model, MESSAGE-China, to analyze the trend of key new power generation technologies and their contributions to GHG mitigation in China. We expect that the traditional renewable technologies, high-efficiency coal power generation and nuclear power will contribute substantially to GHG mitigation in the short term, and that solar power, biomass energy and carbon capture and storage (CCS) will become more important in the middle and long term. In the meantime, in order to fully bring the role of technology progress into play, China needs to enhance the transfer and absorption of international advanced technologies and independently strengthen her ability in research, demonstration and application of new power generation technologies. (author)

  1. New power generation technology options under the greenhouse gases mitigation scenario in China

    Energy Technology Data Exchange (ETDEWEB)

    Qiang, Liu [Graduate University of Chinese Academy of Science, 19A Yu Quan Road, Beijing 100049 (China); Energy Research Institute, Guohong Mansion, Xicheng District, Beijing 100038 (China)], E-mail: liuqiang@eri.org.cn; Minjun, Shi [Graduate University of Chinese Academy of Science, 19A Yu Quan Road, Beijing 100049 (China); Kejun, Jiang [Energy Research Institute, Guohong Mansion, Xicheng District, Beijing 100038 (China)

    2009-06-15

    Climate change has become a global issue. Almost all countries, including China, are now considering adopting policies and measures to reduce greenhouse gas (GHG) emissions. The power generation sector, as a key source of GHG emissions, will also have significant potential for GHG mitigation. One of the key options is to use new energy technologies with higher energy efficiencies and lower carbon emissions. In this article, we use an energy technology model, MESSAGE-China, to analyze the trend of key new power generation technologies and their contributions to GHG mitigation in China. We expect that the traditional renewable technologies, high-efficiency coal power generation and nuclear power will contribute substantially to GHG mitigation in the short term, and that solar power, biomass energy and carbon capture and storage (CCS) will become more important in the middle and long term. In the meantime, in order to fully bring the role of technology progress into play, China needs to enhance the transfer and absorption of international advanced technologies and independently strengthen her ability in research, demonstration and application of new power generation technologies.

  2. Harnessing the Power of Information Technology: Open Business Models in Higher Education

    Science.gov (United States)

    Sheets, Robert G.; Crawford, Stephen

    2012-01-01

    Higher education is under enormous pressure to improve outcomes and reduce costs. Information technology can help achieve these goals, but only if it is properly harnessed. This article argues that one key to harnessing information technology is business model innovation that results in more "open" and "unbundled" operations in learning and…

  3. Power-up: A Reanalysis of 'Power Failure' in Neuroscience Using Mixture Modeling.

    Science.gov (United States)

    Nord, Camilla L; Valton, Vincent; Wood, John; Roiser, Jonathan P

    2017-08-23

    Recently, evidence for endemically low statistical power has cast neuroscience findings into doubt. If low statistical power plagues neuroscience, then this reduces confidence in the reported effects. However, if statistical power is not uniformly low, then such blanket mistrust might not be warranted. Here, we provide a different perspective on this issue, analyzing data from an influential study reporting a median power of 21% across 49 meta-analyses (Button et al., 2013). We demonstrate, using Gaussian mixture modeling, that the sample of 730 studies included in that analysis comprises several subcomponents so the use of a single summary statistic is insufficient to characterize the nature of the distribution. We find that statistical power is extremely low for studies included in meta-analyses that reported a null result and that it varies substantially across subfields of neuroscience, with particularly low power in candidate gene association studies. Therefore, whereas power in neuroscience remains a critical issue, the notion that studies are systematically underpowered is not the full story: low power is far from a universal problem. SIGNIFICANCE STATEMENT Recently, researchers across the biomedical and psychological sciences have become concerned with the reliability of results. One marker for reliability is statistical power: the probability of finding a statistically significant result given that the effect exists. Previous evidence suggests that statistical power is low across the field of neuroscience. Our results present a more comprehensive picture of statistical power in neuroscience: on average, studies are indeed underpowered-some very seriously so-but many studies show acceptable or even exemplary statistical power. We show that this heterogeneity in statistical power is common across most subfields in neuroscience. This new, more nuanced picture of statistical power in neuroscience could affect not only scientific understanding, but potentially

  4. 36 CFR 1275.52 - Restriction of materials of general historical significance unrelated to abuses of governmental...

    Science.gov (United States)

    2010-07-01

    ... general historical significance unrelated to abuses of governmental power. 1275.52 Section 1275.52 Parks... abuses of governmental power. (a) The Archivist will restrict access to materials determined during the processing period to be of general historical significance, but not related to abuses of governmental power...

  5. Gigawatt peak power generation in a relativistic klystron amplifier driven by 1 kW seed-power

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Y. [Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900 (China); Science and Technology on High Power Microwave Laboratory, Mianyang 621900 (China); Xie, H. Q. [College of Science, Southwestern University of Science and Technology, Mianyang 621010 (China); Li, Z. H.; Zhang, Y. J.; Ma, Q. S. [Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900 (China)

    2013-11-15

    An S-band high gain relativistic klystron amplifier driven by kW-level RF power is proposed and studied experimentally. In the device, the RF lossy material is introduced to suppress higher mode excitation. An output power of 1.95 GW with a gain of 62.8 dB is obtained in the simulation. Under conditions of an input RF power of 1.38 kW, a microwave pulse with power of 1.9 GW, frequency of 2.86 GHz, and duration of 105 ns is generated in the experiment, and the corresponding gain is 61.4 dB.

  6. Gigawatt peak power generation in a relativistic klystron amplifier driven by 1 kW seed-power

    Science.gov (United States)

    Wu, Y.; Xie, H. Q.; Li, Z. H.; Zhang, Y. J.; Ma, Q. S.

    2013-11-01

    An S-band high gain relativistic klystron amplifier driven by kW-level RF power is proposed and studied experimentally. In the device, the RF lossy material is introduced to suppress higher mode excitation. An output power of 1.95 GW with a gain of 62.8 dB is obtained in the simulation. Under conditions of an input RF power of 1.38 kW, a microwave pulse with power of 1.9 GW, frequency of 2.86 GHz, and duration of 105 ns is generated in the experiment, and the corresponding gain is 61.4 dB.

  7. Power market model with energy- and power dimension

    International Nuclear Information System (INIS)

    Johnsen, T.A.; Larsen, B.M.

    1995-01-01

    This report discusses a mathematical model of the Norwegian power market. The year is divided into three seasons. Each season is subdivided into a high-load period and a low-load period according to the demand. High-load occurs in daytime on workdays while low-load occurs at night and on holidays. The model is intended to be a tool for studying variations in prices, production, demand and trade throughout the year in a market of free competition. The model establishes equilibrium prices of electricity in Norway in high-load and low-load periods. Equilibrium prices with added transport tariffs and charges give customer an indication of the cost of using electricity. And the equilibrium prices indicate to the power producers the value of further energy or power capacity. Examples of calculations using the model show that extended export and import between Norway and other countries affect power prices and production in Norway. In the examples, power intensive industry and wood processing are subjected to market prices on energy. World market prices which give unilateral power export in the high-load periods cause the Norwegian power prices to rise strongly. If to the export from Norway in periods of high-load there corresponds import in periods of low-load, then the pressure on the prices in the power market is significantly reduced. A more extensive power exchange implies that foreign power producers may use the Norwegian power system to avoid large variations in their thermal power production. 23 refs., 21 figs., 1 tab

  8. Alternative power generation concepts for space

    International Nuclear Information System (INIS)

    Brandhorst, H.W. Jr.; Juhasz, A.J.; Jones, B.I.

    1994-01-01

    With the advent of the NASA Space Station, there has emerged a general realization that large quantities of power in space are necessary and, in fact, enabling. This realization has led to the examination of alternative options to the ubiquitous solar array/battery power system. Several factors led to the consideration of solar dynamic and nuclear power systems. These include better scaling to high power levels, higher efficiency conversion and storage subsystems, and lower system specific mass. The objective of this paper is to present the results of trade and optimization studies that high-light the potential of solar and nuclear dynamic systems relative to photovoltaic power systems

  9. Solar Power Sources

    DEFF Research Database (Denmark)

    Kim, Katherine A.; Mentesidi, Konstantina; Yang, Yongheng

    2017-01-01

    a significant change. Beyond this energy transition, the still declining cost of the solar technology has become an important driving force for more solar-powered systems. However, high penetration of solar-powered systems also brings technical challenges to the entire energy systems. In order to fully address......Solar power is highly abundant, relatively reliable, and not limited to a geographic region, making it one of the most important renewable energy sources. Catering for a clean and green energy system, solar energy will be an active player in the future mixed power grid that is also undergoing...... those issues, the technological properties of solar power should be investigated. Thus, the basics of solar power technology will be introduced and discussed in this chapter....

  10. Multi-Fresnel lenses pumping approach for improving high-power Nd:YAG solar laser beam quality.

    Science.gov (United States)

    Liang, Dawei; Almeida, Joana

    2013-07-20

    To significantly improve the present-day high-power solar laser beam quality, a three-stage multi-Fresnel lenses approach is proposed for side-pumping either a Nd:YAG single-crystal or a core-doped Sm(3+)Nd:YAG ceramic rod. Optimum pumping and laser beam parameters are found through ZEMAX and LASCAD numerical analysis. The proposed scheme offers a uniform absorption profile along the rod. 167 W laser power can be achieved, corresponding to 29.3 W/m(2) collection efficiency. High brightness figure of merit of 8.34 W is expected for the core-doped rod within a convex-concave resonator, which is 1300 times higher than that of the most-recent high-power solar laser.

  11. Land Warrior Power Management

    National Research Council Canada - National Science Library

    Sanders, David

    2003-01-01

    .... The improvement is incremental; yet the goal of power management for this system is to significantly increase the length of time a single source can supply the system with power without resupply...

  12. Well-Being Analysis of Power Systems Considering Increasing Deployment of Gas Turbines

    Directory of Open Access Journals (Sweden)

    Bomiao Liang

    2017-07-01

    Full Text Available With the significant decrease in natural gas prices in many parts of the world, the employment of gas turbine (GT units has increased steadily in recent years. The ever-increasing deployment of GT units is strengthening the interconnections between electric power and natural gas systems, which could provide a higher level of operational flexibility and reliability. As a result, the planning and operation issues in the interconnected electric power and natural gas systems have aroused concern. In these circumstances, the impacts of increasing deployment of GT units in power system operation are studied and evaluated through well-being analysis (WBA. The fast responsive characteristics of GT units are analyzed first, and the definition and adaption of WBA in a power system with increasing deployment of GT units are addressed. Then the equivalent reserve capacity of GT units is estimated, taking demand fluctuations, commitment plans, and operational risks of GT units into account. The WBA of a power system with increasing deployment of GT units is conducted considering the uncertainties of system operation states and renewable energy sources. Finally, the proposed methods are validated through an integrated version of the IEEE 118-bus power system and a 10-bus natural gas system, and the impacts of GT units on power system security under various penetration levels are examined. Simulation results demonstrate that the role of a GT unit as a low-cost electricity producer may conflict with its role as a reserve provider, but through maintaining a proper proportion of idle GT capacities for reserve, the well-being performance of the power system concerned can be significantly improved.

  13. The Fourth Revolution; Instructional Technology in Higher Education.

    Science.gov (United States)

    Carnegie Commission on Higher Education , Berkeley, CA.

    The technology of communications and data processing that has had a profound impact on American Society generally in recent decades promises to have powerful influences on higher education as well. What these influences may be and what steps should be taken to assure that the benefits of instructional technology will be realized in an orderly and…

  14. Jobs for partners - significant stabilization factor for personnel of East Slovakia nuclear power plant

    International Nuclear Information System (INIS)

    Uvirova, E.

    1987-01-01

    The problem is discussed of employment of the wives of operating personnel of the nuclear power plant to be built in East Slovakia. It is expected that almost a half of the number of the wives have completed secondary education with final examination. A list is presented of openings best suitable for women. It is estimated that jobs for 1,580 women will have to be provided of which number 253 will be specialized jobs in health care and education. An increased number of vacancies are expected to be available, especially in the Kosice and Presov towns. (J.B.). 4 tabs., 4 refs

  15. Development of Quantitative Framework for Event Significance Evaluation

    International Nuclear Information System (INIS)

    Lee, Durk Hun; Kim, Min Chull; Kim, Inn Seock

    2010-01-01

    There is an increasing trend in quantitative evaluation of the safety significance of operational events using Probabilistic Safety Assessment (PSA) technique. An integrated framework for evaluation of event significance has been developed by Korea Institute of Nuclear Safety (KINS), which consists of an assessment hierarchy and a number of matrices. The safety significance of various events, e.g., internal or external initiating events that occurred during at-power or shutdown conditions, can be quantitatively analyzed using this framework, and then, the events rated according to their significance. This paper briefly describes the basic concept of the integrated quantitative framework for evaluation of event significance, focusing on the assessment hierarchy

  16. Validity and reproducibility of the ErgomoPro power meter compared with the SRM and Powertap power meters.

    Science.gov (United States)

    Duc, Sebastien; Villerius, Vincent; Bertucci, William; Grappe, Frederic

    2007-09-01

    The ErgomoPro (EP) is a power meter that measures power output (PO) during outdoor and indoor cycling via 2 optoelectronic sensors located in the bottom bracket axis. The aim of this study was to determine the validity and the reproducibility of the EP compared with the SRM crank set and Powertap hub (PT). The validity of the EP was tested in the laboratory during 8 submaximal incremental tests (PO: 100 to 400 W), eight 30-min submaximal constant-power tests (PO = 180 W), and 8 sprint tests (PO > 750 W) and in the field during 8 training sessions (time: 181 +/- 73 min; PO: approximately 140 to 160 W). The reproducibility was assessed by calculating the coefficient of PO variation (CV) during the submaximal incremental and constant tests. The EP provided a significantly higher PO than the SRM and PT during the submaximal incremental test: The mean PO differences were +6.3% +/- 2.5% and +11.1% +/- 2.1% respectively. The difference was greater during field training sessions (+12.0% +/- 5.7% and +16.5% +/- 5.9%) but lower during sprint tests (+1.6% +/- 2.5% and +3.2% +/- 2.7%). The reproducibility of the EP is lower than those of the SRM and PT (CV = 4.1% +/- 1.8%, 1.9% +/- 0.4%, and 2.1% +/- 0.8%, respectively). The EP power meter appears less valid and reliable than the SRM and PT systems.

  17. Higher order mode analysis of the SNS superconducting linac

    CERN Document Server

    Sang Ho Kim; Dong Jeon; Sundelin, R

    2001-01-01

    Higher order modes (HOM's) of monopoles, dipoles, quadrupoles and sextupoles in beta =0.61 and beta =0.81 6-cell superconducting (SC) cavities for the Spallation Neutron Source (SNS) project, have been found up to about 3 GHz and their properties such as R/Q, trapping possibility, etc have been figured out concerning manufacturing imperfection. The main issues of HOM's are beam instabilities (published separately) and HOM induced power especially from TM monopoles. The time structure of SNS beam has three different time scales of pulses, which are micro-pulse, midi-pulse and macropulse. Each time structure will generate resonances. When a mode is near these resonance frequencies, the induced voltage could be large and accordingly the resulting HOM power. In order to understand the effects from such a complex beam time structure on the mode excitation and resulting HOM power, analytic expressions are developed. With these analytic expressions, the induced HOM voltage and HOM power were calculated by assuming e...

  18. Water Powered Bioassay System

    National Research Council Canada - National Science Library

    Lin, Liwei

    2004-01-01

    ... of 0.2 1/hr without requiring electrical power. A low-leakage, hole-in-the-wall micro valve was demonstrated that provided fluidic resistance 255 times higher in the closed state than in the open state...

  19. Increase in the import of the electric power

    International Nuclear Information System (INIS)

    Kangas, H.

    2000-01-01

    Exceptionally large amounts of electric power were imported in Finland from Sweden during the spring and early summer. The reason for this was the good conditions for production of hydroelectric power. Because of the imports it has been possible to reduce the generation of the expensive domestic condensing power. The consumption of electric power increased, compared to May 1998, by 1.7%. The private consumption of electric power was 7-8% due to the lower average temperature of the year 1999. May 1999 has been about two deg C lower than the long-term average. About 6.1 TWh of power was consumed in Finland in May 1999, while the consumption in May 1998 was about 100 GWh lower. The power consumption of the past 12 months was 76.9 TWh, which is about 2.1% higher than the value of the previous 12 months. The long lasting increase in production of hydroelectric power started to cease. The hydroelectric power generated in May-June 1999 exceeded 1.2 TWh, the reduction, compared to the previous year, was only a little over 5%. The production of hydroelectric power during the past 12 months was 15.4 TWh. This corresponds to 20% of the total power demand in Finland. The corresponding value of the previous year was nearly 22%. The generation of wind power in May-June 1999 was about 5 GWh, the amount of the previous 12 months being 29 GWh. Both of these values are about twice higher than the figures of the 12 months before that. The power generation capacity of Finnish nuclear power plants in May-June 1999 less than 3.4 TWh, which are about 15% higher than the value of the previous year. The share of nuclear power during May-June 1999 of the total amount of power consumption was 30%. The amount of nuclear power generated during the first half of the year in Finland was more than 11 TWh. The nuclear power generation capacity of the previous 12 months was 21.8 TWh. Cogeneration of power and heat has been nearly the same both in 1998 and 1999, the growth being only 1.4%. The

  20. Accounting for the speed shear in wind turbine power performance measurement

    DEFF Research Database (Denmark)

    Wagner, Rozenn; Courtney, Michael; Gottschall, Julia

    2011-01-01

    The current IEC standard for wind turbine power performance measurement only requires measurement of the wind speed at hub height assuming this wind speed to be representative for the whole rotor swept area. However, the power output of a wind turbine depends on the kinetic energy flux, which...... itself depends on the wind speed profile, especially for large turbines. Therefore, it is important to characterize the wind profile in front of the turbine, and this should be preferably achieved by measuring the wind speed over the vertical range between lower and higher rotor tips. In this paper, we...... describe an experiment in which wind speed profiles were measured in front of a multimegawatt turbine using a ground–based pulsed lidar. Ignoring the vertical shear was shown to overestimate the kinetic energy flux of these profiles, in particular for those deviating significantly from a power law profile...

  1. Great expectations. Projections of nuclear power around the world

    International Nuclear Information System (INIS)

    McDonald, Alan; Rogner, Hans-Holger; Gritsevskyi, Andrii

    2009-01-01

    In its 2008 edition of Energy, Electricity and Nuclear Power Estimates for the Period to 2030, the International Atomic Energy Agency (IAEA) has again revised its projections for nuclear power upwards. Every year since 1981 the IAEA has published 2 updated projections for the world's nuclear power generating capacity, a low projection and a high projection. The low projection is a down to earth, business-as-usual projection. The high projection takes into account government and corporate announcements about longer-term plans for nuclear investments as well as potential new national policies, e.g., to combat climate change. The results for the 2008 projections are presented. In the low projection, the projected nuclear power capacity in 2030 is 473 GW(e), some 27% higher than today's 372 GW(e). In the high projection, nuclear capacity in 2030 is 748 GW(e), double today's capacity. But while projections for nuclear power's future rose, its share of the world's electricity generation today dropped from 15% in 2006 to 14% in 2007. The main reason is that while total global electricity generation rose 4.8% from 2007 to 2008, nuclear electricity actually dropped slightly. The overall message from the IAEA's 2008 edition of Energy, Electricity and Nuclear Power Estimates for the Period to 2030 is that global electricity use will grow significantly, that nuclear power will have to expand more rapidly than it has done recently in order to maintain its share, and that nuclear power can meet the challenge. (orig.)

  2. Managing the higher risks of low-cost high-efficiency advanced power generation technologies

    International Nuclear Information System (INIS)

    Pearson, M.

    1997-01-01

    Independent power producers operate large coal-fired installations and gas turbine combined-cycle (GTCC) facilities. Combined cycle units are complex and their reliability and availability is greatly influenced by mechanical, instrumentation and control weaknesses. It was suggested that these weaknesses could be avoided by tighter specifications and more rigorous functional testing before acceptance by the owner. For the present, the difficulties of developing reliable, lower installed cost/kw, more efficient GTCC designs, pressure for lower NO x emissions with 'dry' combustors continue to be the most difficult challenges for all GT manufacturers

  3. A Subtle Source of Power: The Effect of Having an Expectation on Anticipated Interpersonal Power

    Science.gov (United States)

    BALDWIN, AUSTIN S.; KIVINIEMI, MARC T.; SNYDER, MARK

    2009-01-01

    In 2 studies, the authors tested the hypothesis that having information about another person can be a source of power in interpersonal interactions. In Study 1, the authors randomized participants to receive an expectation about an interaction partner, and the expectation provided an informational advantage for some participants but not for others. Participants with an advantage reported higher perceptions of power than did those who had information that did not confer an advantage; however, the effect was isolated to feelings of informational power. In Study 2, the authors examined whether the effect extended to different types of power when the information did not provide an explicit advantage. In this case, participants who received a more ambiguous expectation reported more diffuse feelings of power. The authors discuss implications for understanding the dynamics of power in social interactions. PMID:19245049

  4. Comparison of the effects of nuclear power plants and thermal power plants on the environment

    International Nuclear Information System (INIS)

    Sivintsev, Yu.V.; Teverovskij, E.N.

    1976-01-01

    A comparison of ecological effects produced by a thermal power station (TPS) and a nuclear power plant (NPP) of similar electric capacity has been made. The ecological advantages of NPP over TPS are revealed in analysis of aerosol and gas blow-out and its danger for the environment. From the above data it follows that TPS as compared with NPP of similar electric capacity produces a 100 and 1000 fold higher air pollution effect than the latter. The dose of TPS radiation effect is minimum 500 times higher than that of NPP at normal operation. Large-scale construction of NPP is one of the most perfect means of atmosphere protection against harmful industrial discharges

  5. A puzzle form of a non-verbal intelligence test gives significantly higher performance measures in children with severe intellectual disability.

    Science.gov (United States)

    Bello, Katrina D; Goharpey, Nahal; Crewther, Sheila G; Crewther, David P

    2008-08-01

    Assessment of 'potential intellectual ability' of children with severe intellectual disability (ID) is limited, as current tests designed for normal children do not maintain their interest. Thus a manual puzzle version of the Raven's Coloured Progressive Matrices (RCPM) was devised to appeal to the attentional and sensory preferences and language limitations of children with ID. It was hypothesized that performance on the book and manual puzzle forms would not differ for typically developing children but that children with ID would perform better on the puzzle form. The first study assessed the validity of this puzzle form of the RCPM for 76 typically developing children in a test-retest crossover design, with a 3 week interval between tests. A second study tested performance and completion rate for the puzzle form compared to the book form in a sample of 164 children with ID. In the first study, no significant difference was found between performance on the puzzle and book forms in typically developing children, irrespective of the order of completion. The second study demonstrated a significantly higher performance and completion rate for the puzzle form compared to the book form in the ID population. Similar performance on book and puzzle forms of the RCPM by typically developing children suggests that both forms measure the same construct. These findings suggest that the puzzle form does not require greater cognitive ability but demands sensory-motor attention and limits distraction in children with severe ID. Thus, we suggest the puzzle form of the RCPM is a more reliable measure of the non-verbal mentation of children with severe ID than the book form.

  6. Development of Dual Power Multirotor System

    Directory of Open Access Journals (Sweden)

    Chin E. Lin

    2017-01-01

    Full Text Available Vertical take-off and landing (VTOL aircraft has good flight characteristics and system performance without runway. The multirotor system has been tried to expand into larger size for longer endurance or higher payload. But the motor power to endurance ratio has been limited. Due to the specific energy of gasoline being much higher than battery, introducing gasoline engine into multirotor system can be considered. This paper proposes a dual power multirotor system to combine a quadrotor using gasoline engines to provide major lift in shorter arm with another quadrotor using brushless DC motors to offer most controllable force with longer arm. System design, fabrication, and verification of the proposed dual power multirotor system development are presented. Preliminary flights have achieved 16 kg payload for long endurance flight. This is useful for various applications with advanced improvements.

  7. TECHNICAL BASIS DOCUMENT FOR AT-POWER SIGNIFICANCE DETERMINATION PROCESS (SDP) NOTEBOOKS

    International Nuclear Information System (INIS)

    AZARM, M.A.; SMANTA, P.K.; MARTINEZ-GURIDI, G.; HIGGINS, J.

    2004-01-01

    To support the assessment of inspection findings as part of the risk-informed inspection in the United States Nuclear Regulatory Commission's (USNRC's) Reactor Oversight Process (ROP), risk inspection notebooks, also called significance determination process (SDP) notebooks, have been developed for each of the operating plants in the United States. These notebooks serve as a tool for assessing risk significance of inspection findings along with providing an engineering understanding of the significance. Plant-specific notebooks are developed to capture plant-specific features, characteristics, and analyses that influence the risk profile of the plant. At the same time, the notebooks follow a consistent set of assumptions and guidelines to assure consistent treatment of inspection findings across the plants. To achieve these objectives, notebooks are designed to provide specific information that are unique both in the manner in which the information is provided and in the way the screening risk assessment is carried out using the information provided. The unique features of the SDP notebooks, the approaches used to present the information for assessment of inspection findings, the assumptions used in consistent modeling across different plants with due credit to plant-specific features and analyses form the technical basis of the SDP notebooks. In this document, the unique features and the technical basis for the notebooks are presented. The types of information that are included and the reasoning/basis for including that information are discussed. The rules and basis for developing the worksheets that are used by the inspectors in the assessment of inspection findings are presented. The approach to modeling plants' responses to different initiating events and specific assumptions/considerations used for each of the reactor types are also discussed

  8. Financing nuclear power

    International Nuclear Information System (INIS)

    Sheriffah Noor Khamseah Al-Idid Syed Ahmad Idid

    2009-01-01

    Global energy security and climate change concerns sparked by escalating oil prices, high population growth and the rapid pace of industrialization are fueling the current interest and investments in nuclear power. Globally, a significant number policy makers and energy industry leaders have identified nuclear power as a favorable alternative energy option, and are presently evaluating either a new or an expanded role for nuclear power. The International Atomic Energy Agency (IAEA) has reported that as of October 2008, 14 countries have plans to construct 38 new nuclear reactors and about 100 more nuclear power plants have been written into the development plans of governments for the next three decades. Hence as new build is expected to escalate, issues of financing will become increasingly significant. Energy supply, including nuclear power, considered as a premium by government from the socio-economic and strategic perspective has traditionally been a sector financed and owned by the government. In the case for nuclear power, the conventional methods of financing include financing by the government or energy entity (utility or oil company) providing part of the funds from its own resources with support from the government. As national financing is, as in many cases, insufficient to fully finance the nuclear power plants, additional financing is sourced from international sources of financing including, amongst others, Export Credit Agencies (ECAs) and Multilateral Development Institutions. However, arising from the changing dynamics of economics, financing and business model as well as increasing concerns regarding environmental degradation , transformations in methods of financing this energy sector has been observed. This paper aims to briefly present on financing aspects of nuclear power as well as offer some examples of the changing dynamics of financing nuclear power which is reflected by the evolution of ownership and management of nuclear power plants

  9. Method of estimating the reactor power distribution

    International Nuclear Information System (INIS)

    Mitsuta, Toru; Fukuzaki, Takaharu; Doi, Kazuyori; Kiguchi, Takashi.

    1984-01-01

    Purpose: To improve the calculation accuracy for the power distribution thereby improve the reliability of power distribution monitor. Constitution: In detector containing strings disposed within a reactor core, movable type neutron flux monitors are provided in addition to position fixed type neutron monitors conventionally disposed so far. Upon periodical monitoring, a power distribution X1 is calculated from a physical reactor core model. Then, a higher power position X2 is detected by position detectors and value X2 is sent to a neutron flux monitor driving device to displace the movable type monitors to a higher power position in each of the strings. After displacement, the value X1 is amended by an amending device using measured values from the movable type and fixed type monitors and the amended value is sent to a reactor core monitor device. Upon failure of the fixed type monitors, the position is sent to the monitor driving device and the movable monitors are displaced to that position for measurement. (Sekiya, K.)

  10. Power blue and green laser diodes and their applications

    Science.gov (United States)

    Hager, Thomas; Strauß, Uwe; Eichler, Christoph; Vierheilig, Clemens; Tautz, Sönke; Brüderl, Georg; Stojetz, Bernhard; Wurm, Teresa; Avramescu, Adrian; Somers, André; Ristic, Jelena; Gerhard, Sven; Lell, Alfred; Morgott, Stefan; Mehl, Oliver

    2013-03-01

    InGaN based green laser diodes with output powers up to 50mW are now well established for variety of applications ranging from leveling to special lighting effects and mobile projection of 12lm brightness. In future the highest market potential for visible single mode profile lasers might be laser projection of 20lm. Therefore direct green single-mode laser diodes with higher power are required. We found that self heating was the limiting factor for higher current operation. We present power-current characteristics of improved R and D samples with up to 200mW in cw-operation. An optical output power of 100mW is reached at 215mA, a current level which is suitable for long term operation. Blue InGaN laser diodes are also the ideal source for phosphor based generation of green light sources of high luminance. We present a light engine based on LARP (Laser Activated Remote Phosphor) which can be used in business projectors of several thousand lumens on screen. We discuss the advantages of a laser based systems in comparison with LED light engines. LARP requires highly efficient blue power laser diodes with output power above 1W. Future market penetration of LARP will require lower costs. Therefore we studied new designs for higher powers levels. R and D chips with power-current characteristics up to 4W in continuous wave operation on C-mount at 25°C are presented.

  11. Environmental assessment of submarine power cables

    Energy Technology Data Exchange (ETDEWEB)

    Isus, Daniel; Martinez, Juan D. [Grupo General Cable Sistemas, S.A., 08560-Manlleu, Barcelona (Spain); Arteche, Amaya; Del Rio, Carmen; Madina, Virginia [Tecnalia Research and Innovation, 20009 San Sebastian (Spain)

    2011-03-15

    Extensive analyses conducted by the European Community revealed that offshore wind energy have relatively benign effects on the marine environment by comparison to other forms of electric power generation [1]. However, the materials employed in offshore wind power farms suffer major changes to be confined to the marine environment at extreme conditions: saline medium, hydrostatic pressure... which can produce an important corrosion effect. This phenomenon can affect on the one hand, to the material from the structural viewpoint and on the other hand, to the marine environment. In this sense, to better understand the environmental impacts of generating electricity from offshore wind energy, this study evaluated the life cycle assessment for some new designs of submarine power cables developed by General Cable. To achieve this goal, three approaches have been carried out: leaching tests, eco-toxicity tests and Life Cycle Assessment (LCA) methodologies. All of them are aimed to obtaining quantitative data for environmental assessment of selected submarine cables. LCA is a method used to assess environmental aspects and potential impacts of a product or activity. LCA does not include financial and social factors, which means that the results of an LCA cannot exclusively form the basis for assessment of a product's sustainability. Leaching tests results allowed to conclude that pH of seawater did not significantly changed by the presence of submarine three-core cables. Although, it was slightly higher in case of broken cable, pH values were nearly equals. Concerning to the heavy metals which could migrate to the aquatic medium, there were significant differences in both scenarios. The leaching of zinc is the major environmental concern during undersea operation of undamaged cables whereas the fully sectioned three-core cable produced the migration of significant quantities of copper and iron apart from the zinc migrated from the galvanized steel. Thus, the tar

  12. Environmental assessment of submarine power cables

    International Nuclear Information System (INIS)

    Isus, Daniel; Martinez, Juan D.; Arteche, Amaya; Del Rio, Carmen; Madina, Virginia

    2011-03-01

    Extensive analyses conducted by the European Community revealed that offshore wind energy have relatively benign effects on the marine environment by comparison to other forms of electric power generation [1]. However, the materials employed in offshore wind power farms suffer major changes to be confined to the marine environment at extreme conditions: saline medium, hydrostatic pressure... which can produce an important corrosion effect. This phenomenon can affect on the one hand, to the material from the structural viewpoint and on the other hand, to the marine environment. In this sense, to better understand the environmental impacts of generating electricity from offshore wind energy, this study evaluated the life cycle assessment for some new designs of submarine power cables developed by General Cable. To achieve this goal, three approaches have been carried out: leaching tests, eco-toxicity tests and Life Cycle Assessment (LCA) methodologies. All of them are aimed to obtaining quantitative data for environmental assessment of selected submarine cables. LCA is a method used to assess environmental aspects and potential impacts of a product or activity. LCA does not include financial and social factors, which means that the results of an LCA cannot exclusively form the basis for assessment of a product's sustainability. Leaching tests results allowed to conclude that pH of seawater did not significantly changed by the presence of submarine three-core cables. Although, it was slightly higher in case of broken cable, pH values were nearly equals. Concerning to the heavy metals which could migrate to the aquatic medium, there were significant differences in both scenarios. The leaching of zinc is the major environmental concern during undersea operation of undamaged cables whereas the fully sectioned three-core cable produced the migration of significant quantities of copper and iron apart from the zinc migrated from the galvanized steel. Thus, the tar

  13. Hydro-thermal power flow scheduling accounting for head variations

    International Nuclear Information System (INIS)

    El-Hawary, M.E.; Ravindranath, K.M.

    1992-01-01

    In this paper the authors treat the problem of optimal economic operation of hydrothermal electric power systems with variable head hydro plants employing the power flow equations to represent the network. Newton's method is used to solve the problem for a number of test systems. A comparison with solutions with fixed head is presented. In general the optimal schedule requires higher slack bus and thermal power generation and cost in the case of variable head hydro plant than that required by the fixed head hydro plant in all demand periods. Correspondingly, the hydro generation is less in the case of variable head hydro plant compared to fixed head hydro plant. A negligible difference in voltage magnitudes in all the time intervals, but it is observed that slightly higher voltages occur in the case of the fixed head hydro plant. Higher power and energy losses occur in the case of variable head hydro plants compared to the fixed head hydro plants

  14. Problems of coal-based power generation

    International Nuclear Information System (INIS)

    Noskievic, P.

    1996-01-01

    Current problems of and future trends in coal-based power generation are discussed. The present situation is as follows: coal, oil and gas contribute to world fossil fuel resources 75%, 14%, and 11%, respectively, and if the current trend will continue, will be depleted in 240, 50, and 60 years, respectively; the maximum resource estimates (including resources that have not yet been discovered) are 50% higher for oil and 100% higher for gas, for coal such estimates have not been made. While the world prices of coal are expected to remain virtually constant, the prices of gas will probably increase to be twice as high in 2010. Thus, the role of coal may be higher in the next century than it is now, provided that due attention is paid to improving the efficiency of coal-fired power plants and reducing their adverse environmental effects. A comparison of economic data for coal-fired and gas-fired power plants is as follows: Investment cost (USD/kW): 1400, 800; fixed running cost (USD/kW.y): 33.67, 9.0; variable running cost (USD/kWh): 0.30, 0.15; power use (kJ/kWh): 10.29, 7.91; annual availability (%): 70, 50; fuel price (USD/GJ): 1.00, 4.30; power price (USD/kWh): 4.28, 5.52. The investment cost for coal-fired plants covers new construction including flue gas purification. The integrated gasification combined cycle (IGCC) seems to be the future of coal-based power generation. The future problems to be addressed include ways to reduce air pollution, improving the efficiency of the gas-steam cycle, and improving the combustion process particularly with a view to reducing substantially its environmental impact. (P.A.). 4 figs., 4 tabs., 9 refs

  15. Soft-Fault Detection Technologies Developed for Electrical Power Systems

    Science.gov (United States)

    Button, Robert M.

    2004-01-01

    The NASA Glenn Research Center, partner universities, and defense contractors are working to develop intelligent power management and distribution (PMAD) technologies for future spacecraft and launch vehicles. The goals are to provide higher performance (efficiency, transient response, and stability), higher fault tolerance, and higher reliability through the application of digital control and communication technologies. It is also expected that these technologies will eventually reduce the design, development, manufacturing, and integration costs for large, electrical power systems for space vehicles. The main focus of this research has been to incorporate digital control, communications, and intelligent algorithms into power electronic devices such as direct-current to direct-current (dc-dc) converters and protective switchgear. These technologies, in turn, will enable revolutionary changes in the way electrical power systems are designed, developed, configured, and integrated in aerospace vehicles and satellites. Initial successes in integrating modern, digital controllers have proven that transient response performance can be improved using advanced nonlinear control algorithms. One technology being developed includes the detection of "soft faults," those not typically covered by current systems in use today. Soft faults include arcing faults, corona discharge faults, and undetected leakage currents. Using digital control and advanced signal analysis algorithms, we have shown that it is possible to reliably detect arcing faults in high-voltage dc power distribution systems (see the preceding photograph). Another research effort has shown that low-level leakage faults and cable degradation can be detected by analyzing power system parameters over time. This additional fault detection capability will result in higher reliability for long-lived power systems such as reusable launch vehicles and space exploration missions.

  16. Advanced power generation using biomass wastes from palm oil mills

    International Nuclear Information System (INIS)

    Aziz, Muhammad; Kurniawan, Tedi; Oda, Takuya; Kashiwagi, Takao

    2017-01-01

    This study focuses on the energy-efficient utilization of both solid and liquid wastes from palm oil mills, particularly their use for power generation. It includes the integration of a power generation system using empty fruit bunch (EFB) and palm oil mill effluent (POME). The proposed system mainly consists of three modules: EFB gasification, POME digestion, and additional organic Rankine cycle (ORC). EFBs are dried and converted into a syngas fuel with high calorific value through integrated drying and gasification processes. In addition, POME is converted into a biogas fuel for power generation. Biogas engine-based cogenerators are used for generating both electricity and heat. The remaining unused heat is recovered by ORC module to generate electricity. The influences of three EFB gasification temperatures (800, 900 and 1000 °C) in EFB gasification module; and working fluids and pressure in ORC module are evaluated. Higher EFB gasification leads to higher generated electricity and remaining heat for ORC module. Power generation efficiency increases from 11.2 to 24.6% in case of gasification temperature is increased from 800 to 1000 °C. In addition, cyclohexane shows highest energy efficiency compared to toluene and n-heptane in ORC module. Higher pressure in ORC module also leads to higher energy efficiency. Finally, the highest total generated power and power generation efficiency obtained by the system are 8.3 MW and 30.4%, respectively.

  17. Alternative off-site power supply improves nuclear power plant safety

    International Nuclear Information System (INIS)

    Gjorgiev, Blaže; Volkanovski, Andrija; Kančev, Duško; Čepin, Marko

    2014-01-01

    Highlights: • Additional power supply for mitigation of the station blackout event in NPP is used. • A hydro power plant is considered as an off-site alternative power supply. • An upgrade of the probabilistic safety assessment from its traditional use is made. • The obtained results show improvement of nuclear power plant safety. - Abstract: A reliable power system is important for safe operation of the nuclear power plants. The station blackout event is of great importance for nuclear power plant safety. This event is caused by the loss of all alternating current power supply to the safety and non-safety buses of the nuclear power plant. In this study an independent electrical connection between a pumped-storage hydro power plant and a nuclear power plant is assumed as a standpoint for safety and reliability analysis. The pumped-storage hydro power plant is considered as an alternative power supply. The connection with conventional accumulation type of hydro power plant is analysed in addition. The objective of this paper is to investigate the improvement of nuclear power plant safety resulting from the consideration of the alternative power supplies. The safety of the nuclear power plant is analysed through the core damage frequency, a risk measure assess by the probabilistic safety assessment. The presented method upgrades the probabilistic safety assessment from its common traditional use in sense that it considers non-plant sited systems. The obtained results show significant decrease of the core damage frequency, indicating improvement of nuclear safety if hydro power plant is introduced as an alternative off-site power source

  18. Nuclear power, climate change and energy security: Exploring British public attitudes

    Energy Technology Data Exchange (ETDEWEB)

    Corner, Adam; Venables, Dan [School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT (United Kingdom); Spence, Alexa [School of Psychology/Horizon Digital Economy Research, University of Nottingham (United Kingdom); Poortinga, Wouter [Welsh School of Architecture, Cardiff University (United Kingdom); School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT (United Kingdom); Demski, Christina [School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT (United Kingdom); Pidgeon, Nick, E-mail: pidgeonn@cardiff.ac.uk [School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT (United Kingdom)

    2011-09-15

    Public attitudes towards nuclear power in the UK have historically been deeply divided, but as concern about climate change and energy security has exerted an increasing influence on British energy policy, nuclear power has been reframed as a low-carbon technology. Previous research has suggested that a significant proportion of people may 'reluctantly accept' nuclear power as a means of addressing the greater threat of climate change. Drawing on the results of a national British survey (n=1822), the current study found that attitudes towards nuclear remain divided, with only a minority expressing unconditional acceptance. In general, people who expressed greater concern about climate change and energy security and possessed higher environmental values were less likely to favour nuclear power. However, when nuclear power was given an explicit 'reluctant acceptance' framing - allowing people to express their dislike for nuclear power alongside their conditional support - concerns about climate change and energy security became positive predictors of support for nuclear power. These findings suggest that concern about climate change and energy security will only increase acceptance of nuclear power under limited circumstances-specifically once other (preferred) options have been exhausted. - Highlights: > We report data from 2005 to 2010 of British attitudes towards nuclear power and climate change. > Changes in attitudes over the time period were relatively modest. > British population remained relatively divided on nuclear power in 2010. > Concern about climate change was negatively related to evaluations of nuclear power. > Different framings of the issue alter the balance of support for nuclear power.

  19. Nuclear power, climate change and energy security: Exploring British public attitudes

    International Nuclear Information System (INIS)

    Corner, Adam; Venables, Dan; Spence, Alexa; Poortinga, Wouter; Demski, Christina; Pidgeon, Nick

    2011-01-01

    Public attitudes towards nuclear power in the UK have historically been deeply divided, but as concern about climate change and energy security has exerted an increasing influence on British energy policy, nuclear power has been reframed as a low-carbon technology. Previous research has suggested that a significant proportion of people may 'reluctantly accept' nuclear power as a means of addressing the greater threat of climate change. Drawing on the results of a national British survey (n=1822), the current study found that attitudes towards nuclear remain divided, with only a minority expressing unconditional acceptance. In general, people who expressed greater concern about climate change and energy security and possessed higher environmental values were less likely to favour nuclear power. However, when nuclear power was given an explicit 'reluctant acceptance' framing - allowing people to express their dislike for nuclear power alongside their conditional support - concerns about climate change and energy security became positive predictors of support for nuclear power. These findings suggest that concern about climate change and energy security will only increase acceptance of nuclear power under limited circumstances-specifically once other (preferred) options have been exhausted. - Highlights: → We report data from 2005 to 2010 of British attitudes towards nuclear power and climate change. → Changes in attitudes over the time period were relatively modest. → British population remained relatively divided on nuclear power in 2010. → Concern about climate change was negatively related to evaluations of nuclear power. → Different framings of the issue alter the balance of support for nuclear power.

  20. Mildly disabled persons with multiple sclerosis use similar net joint power strategies as healthy controls when walking speed increases

    DEFF Research Database (Denmark)

    Brincks, John; Sørensen, Henrik; Dalgas, Ulrik

    2018-01-01

    flexors in mildly disabled persons with MS and healthy controls at different walking speeds. METHODS:Thirteen persons with MS and thirteen healthy controls participated and peak net joint power was calculated using 3D motion analysis. RESULTS:In general, no differences were found between speed......-matched healthy controls and persons with MS, but the fastest walking speed was significantly higher in healthy controls (2.42 m/s vs. 1.70 m/s). The net joint power increased in hip flexors, hip extensors, hip abductors, knee extensors and plantar flexors in both groups, when walking speed increased. Significant...... correlations between changes in walking speed and changes in net joint power of plantar flexors, hip extensors and hip flexors existed in healthy controls and persons with MS, and in net knee extensor absorption power of persons with MS only. CONCLUSION:In contrast to previous studies, these findings suggest...

  1. Power transformers quality assurance

    CERN Document Server

    Dasgupta, Indrajit

    2009-01-01

    About the Book: With the view to attain higher reliability in power system operation, the quality assurance in the field of distribution and power transformers has claimed growing attention. Besides new developments in the material technology and manufacturing processes of transformers, regular diagnostic testing and maintenance of any engineering product may be ascertained by ensuring: right selection of materials and components and their quality checks. application of correct manufacturing processes any systems engineering. the user`s awareness towards preventive maintenance. The

  2. Technology Use in Higher Education Instruction

    Science.gov (United States)

    Elzarka, Sammy

    2012-01-01

    The significance of integrating technology use in higher education instruction is undeniable. The benefits include those related to access to instruction by underserved populations, adequately preparing students for future careers, capitalizing on best instructional practices, developing higher order thinking activities, and engaging students…

  3. Reactor power monitoring device

    International Nuclear Information System (INIS)

    Kono, Shigehiro.

    1990-01-01

    Among a plurality of power monitoring programs in a reactor power monitoring device, rapid response is required for a scram judging program for the power judging processing of scram signals. Therefore, the scram judging program is stored independently from other power monitoring programs, applied with a priority order, and executed in parallel with other programs, to output scram signals when the detected data exceeds a predetermined value. As a result, the capacity required for the scram judging program is reduced and the processing can be conducted in a short period of time. In addition, since high priority is applied to the scram judging program which is divided into a small capacity, it is executed at higher frequency than other programs when they are executed in parallel. That is, since the entire processings for the power monitoring program are repeated in a short cycle, the response speed of the scram signals required for high responsivity can be increased. (N.H.)

  4. UTC Power/Delphi SECA CBS Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Gorman, Michael; Kerr, Rich

    2013-04-04

    The subject report summarizes the results of solid oxide fuel cell development conducted by UTC Power in conjunction with Delphi Automotive Systems under a cost-share program with from October 2008 through March of 2013. Over that period Delphi Automotive Systems developed a nearly four times larger area solid oxide fuel cell stack capable of operating on pre-reformed natural gas and simulated coal gas with durability demonstrated to 5,000 hours and projected to exceed 10,000 hours. The new stack design was scaled to 40-cell stacks with power output in excess of 6.25kW. Delphi also made significant strides in improving the manufacturability, yield and production cost of these solid oxide fuel cells over the course of the program. Concurrently, UTC Power developed a conceptual design for a 120 MW Integrated Gasification Fuel Cell (IGFC) operating on coal syngas with as high as 57% Higher Heating Value (HHV) efficiency as a measure of the feasibility of the technology. Subsequently a 400 kW on-site system preliminary design with 55% Lower Heating Value (LHV) efficiency operating on natural gas was down-selected from eighteen candidate designs. That design was used as the basis for a 25kW breadboard power plant incorporating four Delphi cell stacks that was tested on natural gas before the program was discontinued due to the sale of UTC Power in early 2013. Though the program was cut short of the endurance target of 3,000 hours, many aspects of the technology were proven including: large-area, repeatable cell manufacture, cell stack operation on simulated coal gas and natural gas and integrated power plant operation on natural gas. The potential of the technology for high efficiency stationary electric power generation is clear. Acceptable production costs, durability, and reliability in real world environments are the remaining challenges to commercialization.

  5. Cancer incidence in the vicinity of nuclear power plants in Taiwan: a population-based study.

    Science.gov (United States)

    Wang, Shiow-Ing; Yaung, Chih-Liang; Lee, Long-Teng; Chiou, Shang-Jyh

    2016-01-01

    Numerous antinuclear demonstrations reveal that the public is anxious about the potential health effects caused by nuclear power plants. The purpose of this study is to address the question "Is there a higher cancer incidence rate in the vicinity of nuclear power plants in Taiwan?" The Taiwan Cancer Registry database from 1979 to 2003 was used to compare the standardized incidence rate of the top four cancers with strong evidence for radiation risks between the "plant-vicinity" with those "non-plant-vicinity" groups. All cancer sites, five-leading cancers in Taiwan, and gender-specific cancers were also studied. We also adopted different observation time to compare the incidence rate of cancers between two groups to explore the impact of the observation period. The incidences of leukemia, thyroid, lung, and breast cancer were not significantly different between two groups, but cervix uteri cancer showed higher incidence rates in the plant-vicinity group. The incidence of cervical cancer was not consistently associated with the duration of plant operation, according to a multiyear period comparison. Although there was higher incidence in cervix cancer in the plant-vicinity group, our findings did not provide the crucial evidence that nuclear power plants were the causal factor for some cancers with strong evidence for radiation risks.

  6. Small high cooling power space cooler

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, T. V.; Raab, J.; Durand, D.; Tward, E. [Northrop Grumman Aerospace Systems Redondo Beach, Ca, 90278 (United States)

    2014-01-29

    The small High Efficiency pulse tube Cooler (HEC) cooler, that has been produced and flown on a number of space infrared instruments, was originally designed to provide cooling of 10 W @ 95 K. It achieved its goal with >50% margin when limited by the 180 W output ac power of its flight electronics. It has also been produced in 2 stage configurations, typically for simultaneously cooling of focal planes to temperatures as low as 35 K and optics at higher temperatures. The need for even higher cooling power in such a low mass cryocooler is motivated by the advent of large focal plane arrays. With the current availability at NGAS of much larger power cryocooler flight electronics, reliable long term operation in space with much larger cooling powers is now possible with the flight proven 4 kg HEC mechanical cooler. Even though the single stage cooler design can be re-qualified for those larger input powers without design change, we redesigned both the linear and coaxial version passive pulse tube cold heads to re-optimize them for high power cooling at temperatures above 130 K while rejecting heat to 300 K. Small changes to the regenerator packing, the re-optimization of the tuned inertance and no change to the compressor resulted in the increased performance at 150 K. The cooler operating at 290 W input power achieves 35 W@ 150 K corresponding to a specific cooling power at 150 K of 8.25 W/W and a very high specific power of 72.5 W/Kg. At these powers the cooler still maintains large stroke, thermal and current margins. In this paper we will present the measured data and the changes to this flight proven cooler that were made to achieve this increased performance.

  7. The Geography of Access and Excellence: Spatial Diversity in Higher Education System Design

    Science.gov (United States)

    Metcalfe, Amy Scott

    2009-01-01

    In a "settler society" such as Canada, inequalities in higher education have geo-political dimensions, necessitating a theoretical framework that considers the geographic distribution of material wealth and power. This paper explores both the economic and social implications of the geographical distribution of the higher education system…

  8. Wind farm power production in the changing wind: Robustness quantification and layout optimization

    DEFF Research Database (Denmark)

    Feng, Ju; Shen, Wen Zhong

    2017-01-01

    Wind farms operate often in the changing wind. The wind condition variations in a wide range of time scales lead to the variability of wind farms’ power production. This imposes a major challenge to the power system operators who are facing a higher and higher penetration level of wind power. Thu...

  9. High power communication satellites power systems study

    International Nuclear Information System (INIS)

    Josloff, A.T.; Peterson, J.R.

    1994-01-01

    This paper discusses a DOE-funded study to evaluate the commercial attractiveness of high power communication satellites and assesses the attributes of both conventional photovoltaic and reactor power systems. This study brings together a preeminent US Industry/Russian team to cooperate on the role of high power communication satellites in the rapidly expanding communications revolution. These high power satellites play a vital role in assuring availability of universally accessible, wide bandwidth communications, for high definition TV, super computer networks and other services. Satellites are ideally suited to provide the wide bandwidths and data rates required and are unique in the ability to provide services directly to the users. As new or relocated markets arise, satellites offer a flexibility that conventional distribution services cannot match, and it is no longer necessary to be near population centers to take advantage of the telecommunication revolution. The geopolitical implications of these substantially enhanced communications capabilities will be significant

  10. Higher insulin sensitivity in vegans is not associated with higher mitochondrial density.

    Science.gov (United States)

    Gojda, J; Patková, J; Jaček, M; Potočková, J; Trnka, J; Kraml, P; Anděl, M

    2013-12-01

    Vegans have a lower incidence of insulin resistance (IR)-associated diseases and a higher insulin sensitivity (IS) compared with omnivores. The aim of this study was to examine whether the higher IS in vegans relates to markers of mitochondrial biogenesis and to intramyocellular lipid (IMCL) content. Eleven vegans and 10 matched (race, age, sex, body mass index, physical activity and energy intake) omnivorous controls were enrolled in a case-control study. Anthropometry, bioimpedance (BIA), ultrasound measurement of visceral and subcutaneous fat layer, parameters of glucose and lipid homeostasis, hyperinsulinemic euglycemic clamp and muscle biopsies were performed. Citrate synthase (CS) activity, mitochondrial DNA (mtDNA) and IMCL content were assessed in skeletal muscle samples. Both groups were comparable in anthropometric and BIA parameters, physical activity and protein-energy intake. Vegans had significantly higher glucose disposal (M-value, vegans 8.11±1.51 vs controls 6.31±1.57 mg/kg/min, 95% confidence interval: 0.402 to 3.212, P=0.014), slightly lower IMCL content (vegans 13.91 (7.8 to 44.0) vs controls 17.36 (12.4 to 78.5) mg/g of muscle, 95% confidence interval: -7.594 to 24.550, P=0.193) and slightly higher relative muscle mtDNA amount (vegans 1.36±0.31 vs controls 1.13±0.36, 95% confidence interval:-0.078 to 0.537, P=0.135). No significant differences were found in CS activity (vegans 18.43±5.05 vs controls 18.16±5.41 μmol/g/min, 95% confidence interval: -4.503 to 5.050, P=0.906). Vegans have a higher IS, but comparable mitochondrial density and IMCL content with omnivores. This suggests that a decrease in whole-body glucose disposal may precede muscle lipid accumulation and mitochondrial dysfunction in IR development.

  11. Analysis of thermal cycles and working fluids for power generation in space

    International Nuclear Information System (INIS)

    Tarlecki, Jason; Lior, Noam; Zhang Na

    2007-01-01

    Production of power in space for terrestrial use is of great interest in view of the rapidly rising power demand and its environmental impacts. Space also offers a very low temperature, making it a perfect heat sink for power plants, thus offering much higher efficiencies. This paper focuses on the evaluation and analysis of thermal Brayton, Ericsson and Rankine power cycles operating at space conditions on several appropriate working fluids. Under the examined conditions, the thermal efficiency of Brayton cycles reaches 63%, Ericsson 74%, and Rankine 85%. These efficiencies are significantly higher than those for the computed or real terrestrial cycles: by up to 45% for the Brayton, and 17% for the Ericsson; remarkably 44% for the Rankine cycle even when compared with the best terrestrial combined cycles. From the considered working fluids, the diatomic gases (N 2 and H 2 ) produce somewhat better efficiencies than the monatomic ones in the Brayton and Rankine cycles. The Rankine cycles require radiator areas that are larger by up to two orders of magnitude than those required for the Brayton and Ericsson cycles. The results of the analysis of the sensitivity of the cycle performance parameters to major parameters such as turbine inlet temperature and pressure ratio are presented, equations or examining the effects of fluid properties on the radiator area and pressure drop were developed, and the effects of the working fluid properties on cycle efficiency and on the power production per unit radiator area were explored to allow decisions on the optimal choice of working fluids

  12. US central station nuclear electric generating units: significant milestones

    International Nuclear Information System (INIS)

    1979-09-01

    Listings of US nuclear power plants include significant dates, reactor type, owners, and net generating capacity. Listings are made by state, region, and utility. Tabulations of status, schedules, and orders are also presented

  13. Occult pneumothoraces in Chinese patients with significant blunt chest trauma: radiological classification and proposed clinical significance.

    Science.gov (United States)

    Lee, Ryan K L; Graham, Colin A; Yeung, Janice H H; Ahuja, Anil T; Rainer, Timothy H

    2012-12-01

    An occult pneumothorax (OP) is a pneumothorax not seen on a supine chest X-ray (CXR) but detected on abdominal or thoracic computed tomography (CT) scanning. With the increasing use of CT in the management of significantly injured trauma patients, more OPs are being detected. The aim of this study was to classify OPs diagnosed on thoracic CT (TCT) and correlate them with their clinical significance. Retrospective analysis of prospectively collected trauma registry data. Total 36 (N=36) consecutive significantly injured trauma patients admitted through the emergency department (ED) who sustained blunt chest trauma and underwent TCT between 1 January 2007 and 31 December 2008 were included. OP was defined as the identification (by a consultant radiologist) of a pneumothorax on TCT that had not been detected on supine CXR. OPs were classified by laterality (unilateral/bilateral) and location (apical, basal, non apical/basal). The size of pneumothoraces, severity of injury [including number of associated thoracic injuries and injury severity score (ISS)], length of hospital stay and mortality were compared between groups. The need for tube thoracostomy and clinical outcome were also analysed. Patients with bilateral OPs (N=8) had significantly more associated thoracic injuries (median: 2 vs. 1, p=0.01), higher ISS (median: 35 vs. 23, p=0.02) and longer hospital stay (median: 20 days vs. 11 days, p=0.01) than those with a unilateral OP (N=28). Basal OPs (N=7) were significantly larger than apical (N=10) and non-apical/basal Ops (N=11). Basal OPs were associated with significantly more associated thoracic injuries (median: 2 vs. 1, p=0.01), higher ISS (median: 35 vs. 25, p=0.04) and longer hospital stays (median: 23 days vs. 17 days, p=0.02) than apical Ops, which had higher ISS (median: 35 vs. 25, p=0.04) and longer hospital stays (median: 23 days vs. 15 days, p=0.02) than non-apical/basal OPs. Non-apical/basal OPs were associated with more related injuries (median: 2

  14. Sensitivity of sensor-based sit-to-stand peak power to the effects of training leg strength, leg power and balance in older adults.

    Science.gov (United States)

    Regterschot, G Ruben H; Folkersma, Marjanne; Zhang, Wei; Baldus, Heribert; Stevens, Martin; Zijlstra, Wiebren

    2014-01-01

    Increasing leg strength, leg power and overall balance can improve mobility and reduce fall risk. Sensor-based assessment of peak power during the sit-to-stand (STS) transfer may be useful for detecting changes in mobility and fall risk. Therefore, this study investigated whether sensor-based STS peak power and related measures are sensitive to the effects of increasing leg strength, leg power and overall balance in older adults. A further aim was to compare sensitivity between sensor-based STS measures and standard clinical measures of leg strength, leg power, balance, mobility and fall risk, following an exercise-based intervention. To achieve these aims, 26 older adults (age: 70-84 years) participated in an eight-week exercise program aimed at improving leg strength, leg power and balance. Before and after the intervention, performance on normal and fast STS transfers was evaluated with a hybrid motion sensor worn on the hip. In addition, standard clinical tests (isometric quadriceps strength, Timed Up and Go test, Berg Balance Scale) were performed. Standard clinical tests as well as sensor-based measures of peak power, maximal velocity and duration of normal and fast STS showed significant improvements. Sensor-based measurement of peak power, maximal velocity and duration of normal STS demonstrated a higher sensitivity (absolute standardized response mean (SRM): ≥ 0.69) to the effects of training leg strength, leg power and balance than standard clinical measures (absolute SRM: ≤ 0.61). Therefore, the presented sensor-based method appears to be useful for detecting changes in mobility and fall risk. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Demonstration tokamak fusion power plant for early realization of net electric power generation

    International Nuclear Information System (INIS)

    Hiwatari, R.; Okano, K.; Asaoka, Y.; Shinya, K.; Ogawa, Y.

    2005-01-01

    A demonstration tokamak fusion power plant Demo-CREST is proposed as the device for early realization of net electric power generation by fusion energy. The plasma configuration for Demo-CREST is optimized to satisfy the electric breakeven condition (the condition for net electric power, P e net = 0 MW) with the plasma performance of the ITER reference operation mode. This optimization method is considered to be suitable for the design of a demonstration power plant for early realization of net electric power generation, because the demonstration power plant has to ensure the net electric generation. Plasma performance should also be more reliably achieved than in past design studies. For the plasma performance planned in the present ITER programme, net electric power from 0 to 500 MW is possible with Demo-CREST under the following engineering conditions: maximum magnetic field 16 T, thermal efficiency 30%, NBI system efficiency 50% and NBI current drive power restricted to 200 MW. By replacing the blanket system with one of higher thermal efficiency, a net electric power of about 1000 MW is also possible so that the performance of the commercial plant with Demo-CREST can also be studied from the economic point of view. The development path from the experimental reactor 'ITER' to the commercial plant 'CREST' through the demonstration power plant 'Demo-CREST' is proposed as an example of the fast track concept. (author)

  16. Troubleshooting of signal power supply system for Shanghai metro line 7

    Science.gov (United States)

    Lu, Kaixia; Xiao, Jie

    2018-03-01

    With the rapid development of Urban Rail Transit Signal Technology, the demand of signal power supply system for signal equipment is higher and higher. The signal intelligent power supply panel is the main component of the urban rail traffic signal power supply system. Whether the intelligent power supply panel working or not is directly related to traffic safety. The maintenance of intelligent signal power supply panel is particularly important. Line 7 of Shanghai Metro adopts PMZG Signal Intelligent Power Supply Panel, which is produced by Beijing Jinyujiaxin Polytron Technologies Inc. Maintenance of power supply system mainly includes routine maintenance and troubleshooting. This article will make clear the routine maintenance contents of PMZG Signal Intelligent Power Supply Panel, and put forward the common fault information and troubleshooting methods of PMZG Signal Intelligent Power Supply Panel. In accordance with the steps of fault handling, the faults can be eliminated in the shortest possible time, and PMZG Signal Intelligent Power Supply Panel can be quickly restored to normal working state.

  17. Shunt hybrid active power filter for harmonic mitigation: A practical ...

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... The increasing importance of Power Quality problems has been responsible for several improvements in Active Power Filter (APF) typologies in the last decade. The increased cost and switching losses make a pure shunt APF economically impractical for high power applications. In higher power levels ...

  18. Shunt hybrid active power filter for harmonic mitigation: A practical ...

    Indian Academy of Sciences (India)

    The increasing importance of Power Quality problems has been responsible for several improvements in Active Power Filter (APF) typologies in the last decade. The increased cost and switching losses make a pure shunt APF economically impractical for high power applications. In higher power levels shunt Hybrid Active ...

  19. Low power constant fraction discriminator

    International Nuclear Information System (INIS)

    Krishnan, Shanti; Raut, S.M.; Mukhopadhyay, P.K.

    2001-01-01

    This paper describes the design of a low power ultrafast constant fraction discriminator, which significantly reduces the power consumption. A conventional fast discriminator consumes about 1250 MW of power whereas this low power version consumes about 440 MW. In a multi detector system, where the number of discriminators is very large, reduction of power is of utmost importance. This low power discriminator is being designed for GRACE (Gamma Ray Atmospheric Cerenkov Experiments) telescope where 1000 channels of discriminators are required. A novel method of decreasing power consumption has been described. (author)

  20. Power grid operation risk management: V2G deployment for sustainable development

    Science.gov (United States)

    Haddadian, Ghazale J.

    The production, transmission, and delivery of cost--efficient energy to supply ever-increasing peak loads along with a quest for developing a low-carbon economy require significant evolutions in the power grid operations. Lower prices of vast natural gas resources in the United States, Fukushima nuclear disaster, higher and more intense energy consumptions in China and India, issues related to energy security, and recent Middle East conflicts, have urged decisions makers throughout the world to look into other means of generating electricity locally. As the world look to combat climate changes, a shift from carbon-based fuels to non-carbon based fuels is inevitable. However, the variability of distributed generation assets in the electricity grid has introduced major reliability challenges for power grid operators. While spearheading sustainable and reliable power grid operations, this dissertation develops a multi-stakeholder approach to power grid operation design; aiming to address economic, security, and environmental challenges of the constrained electricity generation. It investigates the role of Electric Vehicle (EV) fleets integration, as distributed and mobile storage assets to support high penetrations of renewable energy sources, in the power grid. The vehicle-to-grid (V2G) concept is considered to demonstrate the bidirectional role of EV fleets both as a provider and consumer of energy in securing a sustainable power grid operation. The proposed optimization modeling is the application of Mixed-Integer Linear Programing (MILP) to large-scale systems to solve the hourly security-constrained unit commitment (SCUC) -- an optimal scheduling concept in the economic operation of electric power systems. The Monte Carlo scenario-based approach is utilized to evaluate different scenarios concerning the uncertainties in the operation of power grid system. Further, in order to expedite the real-time solution of the proposed approach for large-scale power systems

  1. Power Doppler Ultrasound Evaluation of Peripheral Joint, Entheses, Tendon, and Bursa Abnormalities in Psoriatic Patients: A Clinical Study.

    Science.gov (United States)

    Tang, Yuanjiao; Yang, Yujia; Xiang, Xi; Wang, Liyun; Zhang, Lingyan; Qiu, Li

    2018-04-15

    To evaluate the prevalence rates of peripheral joint, enthesis, tendon, and bursa abnormalities by power Doppler (PD) ultrasonic examination in patients with psoriatic arthritis (PsA), psoriatic patients without clinical signs of arthritis (non-PsA psoriasis group), and healthy individuals, to detect subclinical PsA. A total of 253 healthy volunteers, 242 non-PsA psoriatic patients, and 86 patients with PsA were assessed by 2-dimensional and power Doppler (PD) ultrasound. Peripheral joint, enthesis, tendon, and bursa abnormalities were observed, characterizing abnormal PD. The affected patients and sites with abnormalities in various ages were compared among groups; PD signal grades for the abnormalities were also compared. In the PsA group, significantly higher percentages of sites showing joint effusion/synovitis, enthesitis, and tenosynovitis in all age groups, and markedly higher rates of sites with bursitis were found in young and middle age groups, compared with the non-PsA and control groups (all p the non-PsA group showed significantly higher rates of joint effusion/synovitis and enthesitis sites, and elevated PD signal grades of synovitis, enthesitis, and tenosynovitis in comparison with the control group, both in young and middle age groups (all p tenosynovitis.

  2. Solar cells from 120 PPMA carbon-contaminated feedstock without significantly higher reverse current or shunt

    Energy Technology Data Exchange (ETDEWEB)

    Manshanden, P.; Coletti, G. [ECN Solar Energy, Petten (Netherlands)

    2012-09-15

    In a bid to drive down the cost of silicon wafers, several options for solar grade silicon feedstock have been investigated over the years. All methods have in common that the resulting silicon contains higher levels of impurities like dopants, oxygen, carbon or transition metals, the type and level of impurities depending on the raw materials and refining processes. In this work wafers from a p-type mc-Si ingot made with feedstock contaminated with 120 ppma of carbon have been processed into solar cells together with reference uncontaminated feedstock from semiconductor grade polysilicon with <0.4 ppma carbon. The results show that comparable reverse current, shunts, and efficiencies can be reached for both types of wafers. Gettering and defect hydrogenation effectiveness also did not deviate from the reference. Electroluminescence pictures do not show increased hotspot formation, even at -16V.

  3. Cycling peak power in obese and lean 6- to 8-year-old girls and boys.

    Science.gov (United States)

    Aucouturier, Julien; Lazaar, Nordine; Doré, Eric; Meyer, Martine; Ratel, Sebastien; Duché, Pascale

    2007-06-01

    The purpose of this study was to investigate the possible effect of the difference in percentage body fat (%BF) and fat-free mass (FFM) on cycling peak power (CPP) in 6- to 8-year-old obese and lean untrained girls and boys. Obese (35 girls, 35 boys) and lean (35 girls, 35 boys) children were measured for obesity, %BF, calculated from skinfold measurements. FFM was calculated as body mass (BM) minus body fat. A force-velocity test on a cycle ergometer was used to measure CPP. CPP was related to anthropometric variables using standard and allometric models. CPP in absolute terms was higher in obese children than in lean children irrespective of gender. BM-related CPP was significantly lower in obese children than in lean ones, whereas no effect of obesity appeared on FFM-related CPP. Velocity at CPP (Vopt) was significantly lower and force at CPP (Fopt) was significantly higher in girls than in boys. Muscle power production was unaffected by obesity in children. Low BM-related CPP could explain the difficulty of taking up physical activities that are body-mass related in obese children. Gender difference for Vopt and Fopt shows that girls and boys may have different maturation patterns affecting CPP.

  4. Carbon price instead of support schemes: wind power investments by the electricity market

    International Nuclear Information System (INIS)

    Petitet, Marie; Finon, Dominique; Janssen, Tanguy

    2014-10-01

    In this paper we study the development of wind power by the electricity market without any usual support scheme which is aimed at subsidizing non mature renewables, with the sole incentive of a significant carbon price. Long term electricity market and investment decisions simulation by system dynamics modelling is used to trace the electricity generation mix evolution over a 20-year period in a pure thermal system. A range of stable carbon price, as a tax could be, is tested in order to determine the value above which wind power development by market forces becomes economically possible. Not only economic competitiveness in terms of cost price, but also profitability against traditional fossil fuel technologies are necessary for a market-driven development of wind power. Results stress that wind power is really profitable for investors only if the carbon price is very significantly higher than the price required for making wind power MWh's cost price competitive with CCGT and coal-fired plants on the simplistic basis of levelized costs. In this context, the market-driven development of wind power seems only possible if there is a strong commitment to climate policy, reflected by the preference for a stable and high carbon price rather than a fuzzy price of an emission trading scheme. Besides, results show that market-driven development of wind power would require a sky-rocketing carbon price if the initial technology mix includes a share of nuclear plants even with a moratorium on new nuclear development. (authors)

  5. Flexibility in 21st Century Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, J.; Miller, M.; Zinaman, O.; Milligan, M.; Arent, D.; Palmintier, B.; O' Malley, M.; Mueller, S.; Lannoye, E.; Tuohy, A.; Kujala, B.; Sommer, M.; Holttinen, H.; Kiviluoma, J.; Soonee, S. K.

    2014-05-01

    Flexibility of operation--the ability of a power system to respond to change in demand and supply--is a characteristic of all power systems. Flexibility is especially prized in twenty-first century power systems, with higher levels of grid-connected variable renewable energy (primarily, wind and solar). This paper summarizes the analytic frameworks that have emerged to measure this characteristic and distills key principles of flexibility for policy makers.

  6. Simulation of interaction between wind farm and power system[Flicker

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, P.; Hansen, A.; Janosi, L.; Bech, J.; Bak-Jensen, B.

    2001-12-01

    A dynamic model of the wind farm Hagesholm has been implemented in the dedicated power system simulation program DIgSILENT. The wind farm consists of six 2MW NM2000/72 wind turbines from NEG-Micon. The model has been verified using simultaneous power quality measurements on the 10 kV terminals of a single wind turbine and power performance measurements on two wind turbines. The verification shows a generally good agreement between simulations and measurements, although the simulations at higher wind speeds seem to underestimate the power and voltage fluctuations. A way to improve the simulation at higher wind speeds is suggested. (au)

  7. Significance of acceleration period in a dynamic strength testing study.

    Science.gov (United States)

    Chen, W L; Su, F C; Chou, Y L

    1994-06-01

    The acceleration period that occurs during isokinetic tests may provide valuable information regarding neuromuscular readiness to produce maximal contraction. The purpose of this study was to collect the normative data of acceleration time during isokinetic knee testing, to calculate the acceleration work (Wacc), and to determine the errors (ERexp, ERwork, ERpower) due to ignoring Wacc during explosiveness, total work, and average power measurements. Seven male and 13 female subjects attended the test by using the Cybex 325 system and electronic stroboscope machine for 10 testing speeds (30-300 degrees/sec). A three-way ANOVA was used to assess gender, direction, and speed factors on acceleration time, Wacc, and errors. The results indicated that acceleration time was significantly affected by speed and direction; Wacc and ERexp by speed, direction, and gender; and ERwork and ERpower by speed and gender. The errors appeared to increase when testing the female subjects, during the knee flexion test, or when speed increased. To increase validity in clinical testing, it is important to consider the acceleration phase effect, especially in higher velocity isokinetic testing or for weaker muscle groups.

  8. Effect of pedaling rates and myosin heavy chain composition in the vastus lateralis muscle on the power generating capability during incremental cycling in humans.

    Science.gov (United States)

    Majerczak, J; Szkutnik, Z; Duda, K; Komorowska, M; Kolodziejski, L; Karasinski, J; Zoladz, J A

    2008-01-01

    In this study, we have determined power output reached at maximal oxygen uptake during incremental cycling exercise (P(I, max)) performed at low and at high pedaling rates in nineteen untrained men with various myosin heavy chain composition (MyHC) in the vastus lateralis muscle. On separate days, subjects performed two incremental exercise tests until exhaustion at 60 rev min(-1) and at 120 rev min(-1). In the studied group of subjects P(I, max) reached during cycling at 60 rev min(-1) was significantly higher (p=0.0001) than that at 120 rev min(-1) (287+/-29 vs. 215+/-42 W, respectively for 60 and 120 rev min(-1)). For further comparisons, two groups of subjects (n=6, each) were selected according to MyHC composition in the vastus lateralis muscle: group H with higher MyHC II content (56.8+/-2.79 %) and group L with lower MyHC II content in this muscle (28.6+/-5.8 %). P(I, max) reached during cycling performed at 60 rev min(-1) in group H was significantly lower than in group L (p=0.03). However, during cycling at 120 rev min(-1), there was no significant difference in P(I, max) reached by both groups of subjects (p=0.38). Moreover, oxygen uptake (VO(2)), blood hydrogen ion [H(+)], plasma lactate [La(-)] and ammonia [NH(3)] concentrations determined at the four highest power outputs completed during the incremental cycling performed at 60 as well as 120 rev min(-1), in the group H were significantly higher than in group L. We have concluded that during an incremental exercise performed at low pedaling rates the subjects with lower content of MyHC II in the vastus lateralis muscle possess greater power generating capabilities than the subjects with higher content of MyHC II. Surprisingly, at high pedaling rate, power generating capabilities in the subjects with higher MyHC II content in the vastus lateralis muscle did not differ from those found in the subjects with lower content of MyHC II in this muscle, despite higher blood [H(+)], [La(-)] and [NH(3

  9. Serum Inhibin B and follicle-stimulating hormone levels as tools in the evaluation of infertile men: significance of adequate reference values from proven fertile men

    DEFF Research Database (Denmark)

    Andersson, A.-M.; Petersen, Jørgen Holm; Jørgensen, N.

    2004-01-01

    Inhibin B and FSH levels in 289 idiopathic infertile men were compared with reference materials consisting of 303 proven fertile men (reference group 1) and 307 healthy men from the general population with unknown fertility status (reference group 2). The diagnostic power of these two serum markers...... of spermatogenesis was evaluated by the use of receiver operating characteristic plot analysis, and an example of how both markers can be used simultaneously in a bivariate reference chart is presented. Inhibin B levels were significantly lower and FSH levels were significantly higher in the infertile men, compared...

  10. Modeling of high power ICRF heating experiments on TFTR

    International Nuclear Information System (INIS)

    Phillips, C.K.; Wilson, J.R.; Bell, M.; Fredrickson, E.; Hosea, J.C.; Majeski, R.; Ramsey, A.; Rogers, J.H.; Schilling, G.; Skinner, C.; Stevens, J.E.; Taylor, G.; Wong, K.L.; Murakami, M.

    1993-01-01

    Over the past two years, ICRF heating experiments have been performed on TFTR in the hydrogen minority heating regime with power levels reaching 11.2 MW in helium-4 majority plasmas and 8.4 MW in deuterium majority plasmas. For these power levels, the minority hydrogen ions, which comprise typically less than 10% of the total electron density, evolve into la very energetic, anisotropic non-Maxwellian distribution. Indeed, the excess perpendicular stored energy in these plasmas associated with the energetic minority tail ions is often as high as 25% of the total stored energy, as inferred from magnetic measurements. Enhanced losses of 0.5 MeV protons consistent with the presence of an energetic hydrogen component have also been observed. In ICRF heating experiments on JET at comparable and higher power levels and with similar parameters, it has been suggested that finite banana width effects have a noticeable effect on the ICRF power deposition. In particular, models indicate that finite orbit width effects lead to a reduction in the total stored energy and of the tail energy in the center of the plasma, relative to that predicted by the zero banana width models. In this paper, detailed comparisons between the calculated ICRF power deposition profiles and experimentally measured quantities will be presented which indicate that significant deviations from the zero banana width models occur even for modest power levels (P rf ∼ 6 MW) in the TFTR experiments

  11. Power exhaust scenarios and control for projected high-power NSTX-U operation

    Science.gov (United States)

    Menard, Jonathan; Gerhardt, S. P.; Myers, C. E.; Reinke, M. L.; Brooks, A.; Mardenfeld, M.; NSTX Upgrade Team

    2017-10-01

    An important goal of the NSTX Upgrade (NSTX-U) research program is to characterize energy confinement in the low-aspect-ratio spherical tokamak configuration over a significantly expanded range of plasma current, toroidal field, and heating power, while increasing flattop durations up to 5 seconds. However, the narrowing of the scrape-off layer at higher current combined with an improved understanding of expected halo-current loads has motivated a significant re-design of NSTX-U plasma facing components in the high-heat-flux regions of the divertor. In order to reduce the expected divertor heat flux to acceptable levels, a combination of mitigation techniques will be used: increased divertor poloidal flux expansion, increased divertor radiation, and controlled strike-point sweeping. The machine requirements for these various mitigation techniques are studied here using a newly implemented reduced heat-flux model. Systematic equilibrium scans are used to quantify the required divertor coil currents and to verify vertical stability for a range of plasma shapes. Free-boundary control schemes to constrain the strike-point location and field-line angle-of-incidence will also be discussed. Work supported by DOE contract DE-AC02- 09CH11466.

  12. Quantifying the hurricane catastrophe risk to offshore wind power.

    Science.gov (United States)

    Rose, Stephen; Jaramillo, Paulina; Small, Mitchell J; Apt, Jay

    2013-12-01

    The U.S. Department of Energy has estimated that over 50 GW of offshore wind power will be required for the United States to generate 20% of its electricity from wind. Developers are actively planning offshore wind farms along the U.S. Atlantic and Gulf coasts and several leases have been signed for offshore sites. These planned projects are in areas that are sometimes struck by hurricanes. We present a method to estimate the catastrophe risk to offshore wind power using simulated hurricanes. Using this method, we estimate the fraction of offshore wind power simultaneously offline and the cumulative damage in a region. In Texas, the most vulnerable region we studied, 10% of offshore wind power could be offline simultaneously because of hurricane damage with a 100-year return period and 6% could be destroyed in any 10-year period. We also estimate the risks to single wind farms in four representative locations; we find the risks are significant but lower than those estimated in previously published results. Much of the hurricane risk to offshore wind turbines can be mitigated by designing turbines for higher maximum wind speeds, ensuring that turbine nacelles can turn quickly to track the wind direction even when grid power is lost, and building in areas with lower risk. © 2013 Society for Risk Analysis.

  13. Endurance Wind Power : practical insights into small wind

    International Nuclear Information System (INIS)

    Hicks, D.

    2008-01-01

    This presentation discussed practical issues related to purchasing and installing small wind turbines in Canada. Wind power capacity can be estimated by looking at provincial wind maps as well as by seeking wind data at local airports. Wind resources are typically measured at heights of between 20 meters and 50 m. The height of a wind turbine tower can significantly increase the turbine's wind generating capacity. Turbine rotors should always be placed 30 feet higher than obstacles within 500 feet. Many provinces have now mandated utilities to accept renewable energy resources from grid-connected wind energy plants. Net billing systems are used to determine the billing relationship between power-producing consumers and the utilities who will buy the excess power and sell it to other consumers. Utilities are not yet mandated to purchase excess power, and it is likely that federal and provincial legislation will be needed to ensure that net billing systems continue to grow. Many Canadian municipalities have no ordinances related to wind turbine placements. Consumers interested in purchasing small wind turbines should ensure that the turbine has been certified by an accredited test facility and has an adequate safety system. The noise of the turbine as well as its power performance in relation to the purchaser's needs must also be considered. It was concluded that small wind turbines can provide a means for electricity consumers to reduce their carbon footprint and hedge against the inflationary costs of fossil-fuelled energy resources. tabs., figs

  14. Fuel cycle comparison of distributed power generation technologies

    International Nuclear Information System (INIS)

    Elgowainy, A.; Wang, M.Q.

    2008-01-01

    The fuel-cycle energy use and greenhouse gas (GHG) emissions associated with the application of fuel cells to distributed power generation were evaluated and compared with the combustion technologies of microturbines and internal combustion engines, as well as the various technologies associated with grid-electricity generation in the United States and California. The results were primarily impacted by the net electrical efficiency of the power generation technologies and the type of employed fuels. The energy use and GHG emissions associated with the electric power generation represented the majority of the total energy use of the fuel cycle and emissions for all generation pathways. Fuel cell technologies exhibited lower GHG emissions than those associated with the U.S. grid electricity and other combustion technologies. The higher-efficiency fuel cells, such as the solid oxide fuel cell (SOFC) and molten carbonate fuel cell (MCFC), exhibited lower energy requirements than those for combustion generators. The dependence of all natural-gas-based technologies on petroleum oil was lower than that of internal combustion engines using petroleum fuels. Most fuel cell technologies approaching or exceeding the DOE target efficiency of 40% offered significant reduction in energy use and GHG emissions

  15. Dimensionless Energy Conversion Characteristics of an Air-Powered Hydraulic Vehicle

    OpenAIRE

    Dongkai Shen; Qilong Chen; Yixuan Wang

    2018-01-01

    Due to the advantages of resource conservation and less exhaust emissions, compressed air-powered vehicle has attracted more and more attention. To improve the power and efficiency of air-powered vehicle, an air-powered hydraulic vehicle was proposed. As the main part of the air-powered hydraulic vehicles, HP transformer (short for Hydropneumatic transformer) is used to convert the pneumatic power to higher hydraulic power. In this study, to illustrate the energy conversion characteristics of...

  16. College-Based Case Studies in Using PowerPoint Effectively

    Science.gov (United States)

    Inoue-Smith, Yukiko

    2016-01-01

    This study reexamined PowerPoint's potential to enhance traditional pedagogical practices in higher education. The study addressed (1) the conditions under which PowerPoint meets students' needs in typical lecture-based classrooms, (2) whether professors consider PowerPoint-based lectures more effective than lectures supported by material on…

  17. Power and welfare

    DEFF Research Database (Denmark)

    Mik-Meyer, Nanna; Villadsen, Kasper

    readily evident that power is at stake when institutions educate, counsel or ‘empower’ citizens. This book offers a framework for understanding and analyzing these complex and implicit forms of power at play in the encounters between citizens and welfare institutions. Taking as its starting point the idea......In the welfare provision of today, power takes both the shape of juridical sanctions and of attractive offers for self-development. When state institutions punish criminals, remove children at risk, or enforce sanctions upon welfare recipients the question of power is immediately urgent. It is less...... that power takes many different shapes, and that different approaches to power may be necessary in the diverse contexts where citizens encounter welfare professionals, the book demonstrates how significant social theorists, spanning from Goffman to Foucault, can be used for inquiries into these encounters...

  18. Power and Welfare

    DEFF Research Database (Denmark)

    Mik-Meyer, Nanna; Villadsen, Kaspar

    readily evident that power is at stake when institutions educate, counsel or 'empower' citizens. This book offers a framework for understanding and analyzing these complex and implicit forms of power at play in the encounters between citizens and welfare institutions. Taking as its starting point the idea......In the welfare provision of today, power takes both the shape of juridical sanctions and of attractive offers for self-development. When state institutions punish criminals, remove children at risk, or enforce sanctions upon welfare recipients the question of power is immediately urgent. It is less...... that power takes many different shapes, and that different approaches to power may be necessary in the diverse contexts where citizens encounter welfare professionals, the book demonstrates how significant social theorists, spanning from Goffman to Foucault, can be used for inquiries into these encounters...

  19. Power Electronics Thermal Management R&D (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Waye, S.

    2014-11-01

    This project will investigate and develop thermal-management strategies for wide bandgap (WBG)-based power electronics systems. Research will be carried out to deal with thermal aspects at the module- and system-level. Module-level research will focus on die- and substrate-integrated cooling strategies and heat-transfer enhancement technologies. System-level research will focus on thermal-management strategies for the entire power electronics system to enable smart packaging solutions. One challenge with WBG device-based power electronics is that although losses in the form of heat may be lower, the footprint of the components is also likely to be reduced to reduce cost, weight, and volume. Combined with higher operational temperatures, this creates higher heat fluxes which much be removed from a smaller footprint, requiring advanced cooling strategies.

  20. High power communication satellites power systems study

    Science.gov (United States)

    Josloff, Allan T.; Peterson, Jerry R.

    1995-01-01

    This paper discusses a planned study to evaluate the commercial attractiveness of high power communication satellites and assesses the attributes of both conventional photovoltaic and reactor power systems. These high power satellites can play a vital role in assuring availability of universally accessible, wide bandwidth communications, for high definition TV, super computer networks and other services. Satellites are ideally suited to provide the wide bandwidths and data rates required and are unique in the ability to provide services directly to the users. As new or relocated markets arise, satellites offer a flexibility that conventional distribution services cannot match, and it is no longer necessary to be near population centers to take advantage of the telecommunication revolution. The geopolitical implications of these substantially enhanced communications capabilities can be significant.

  1. Modeling and control of sustainable power systems. Towards smarter and greener electric grids

    Energy Technology Data Exchange (ETDEWEB)

    Lingfeng Wang (ed.) [Toledo Univ., OH (United States). Electrical Engineering and Computer Science Dept.

    2012-07-01

    The concept of the smart grid promises the world an efficient and intelligent approach of managing energy production, transportation, and consumption by incorporating intelligence, efficiency, and optimality into the power grid. Both energy providers and consumers can take advantage of the convenience, reliability, and energy savings achieved by real-time and intelligent energy management. To this end, the current power grid is experiencing drastic changes and upgrades. For instance, more significant green energy resources such as wind power and solar power are being integrated into the power grid, and higher energy storage capacity is being installed in order to mitigate the intermittency issues brought about by the variable energy resources. At the same time, novel power electronics technologies and operating strategies are being invented and adopted. For instance, Flexible AC transmission systems and phasor measurement units are two promising technologies for improving the power system reliability and power quality. Demand side management will enable the customers to manage the power loads in an active fashion. As a result, modeling and control of modern power grids pose great challenges due to the adoption of new smart grid technologies. In this book, chapters regarding representative applications of smart grid technologies written by world-renowned experts are included, which explain in detail various innovative modeling and control methods. (orig.)

  2. Power transistor module for high current applications

    International Nuclear Information System (INIS)

    Cilyo, F.F.

    1975-01-01

    One of the parts needed for the control system of the 400-GeV accelerator at Fermilab was a power transistor with a safe operating area of 1800A at 50V, dc current gain of 100,000 and 20 kHz bandwidth. Since the commercially available discrete devices and power hybrid packages did not meet these requirements, a power transistor module was developed which performed satisfactorily. By connecting 13 power transistors in parallel, with due consideration for network and heat dissipation problems, and by driving these 13 with another power transistor, a super power transistor is made, having an equivalent current, power, and safe operating area capability of 13 transistors. For higher capabilities, additional modules can be conveniently added. (auth)

  3. Dynamics of massless higher spins in the second order in curvatures

    Energy Technology Data Exchange (ETDEWEB)

    Vasiliev, M A [International Centre for Theoretical Physics, Trieste (Italy)

    1990-04-05

    The consistent equations of motion of interacting massless fields of all spins s=0, 1/2, 1, ..., {infinity} are constructed explicitly to the second order of the expansion in powers of the higher spin strengths. (orig.).

  4. Innovation on high-power long-pulse gyrotrons

    International Nuclear Information System (INIS)

    Litvak, Alexander; Sakamoto, Keishi; Thumm, Manfred

    2011-01-01

    Progress in the worldwide development of high-power gyrotrons for magnetic confinement fusion plasma applications is described. After technology breakthroughs in research on gyrotron components in the 1990s, significant progress has been achieved in the last decade, in particular, in the field of long-pulse and continuous wave (CW) gyrotrons for a wide range of frequencies. At present, the development of 1 MW-class CW gyrotrons has been very successful; these are applicable for self-ignition experiments on fusion plasmas and their confinement in the tokamak ITER, for long-pulse confinement experiments in the stellarator Wendelstein 7-X (W7-X) and for EC H and CD in the future tokamak JT-60SA. For this progress in the field of high-power long-pulse gyrotrons, innovations such as the realization of high-efficiency stable oscillation in very high order cavity modes, the use of single-stage depressed collectors for energy recovery, highly efficient internal quasi-optical mode converters and synthetic diamond windows have essentially contributed. The total tube efficiencies are around 50% and the purity of the fundamental Gaussian output mode is 97% and higher. In addition, activities for advanced gyrotrons, e.g. a 2 MW gyrotron using a coaxial cavity, multi-frequency 1 MW gyrotrons and power modulation technology, have made progress.

  5. Microbial Reverse Electrodialysis Cells for Synergistically Enhanced Power Production

    KAUST Repository

    Kim, Younggy

    2011-07-01

    A new type of bioelectrochemical system for producing electrical power, called a microbial reverse-electrodialysis cell (MRC), was developed to increase voltages and power densities compared to those generated individually by microbial fuel cells (MFCs) or reverse electrodialysis (RED) systems. In RED systems, electrode overpotentials create significant energy losses due to thermodynamically unfavorable electrode reactions, and therefore a large number of stacked cells must be used to have significant energy recovery. This results in high capital costs for the large number of membranes, and increases energy losses from pumping water through a large number of cells. In an MRC, high overpotentials are avoided through oxidation of organic matter by exoelectrogenic bacteria on the anode and oxygen reduction on the cathode. An MRC containing only five pairs of RED cells, fed solutions typical of seawater (600 mM NaCl) and river water (12 mM NaCl) at 0.85 mL/min, produced up to 3.6 W/m2 (cathode surface area) and 1.2-1.3 V with acetate as a substrate. Pumping accounted for <2% of the produced power. A higher flow rate (1.55 mL/min) increased power densities up to 4.3 W/m2. COD removal was 98% with a Coulombic efficiency of 64%. Power production by the individual components was substantially lower with 0.7 W/m2 without salinity driven energy, and <0.015 W/m2 with reduced exoelectrogenic activity due to substrate depletion. These results show that the combination of an MFC and a RED stack synergistically increases performance relative to the individual systems, producing a new type of system that can be used to more efficiently capture salinity driven energy from seawater and river water. © 2011 American Chemical Society.

  6. Detecting, categorizing and forecasting large romps in wind farm power output using meteorological observations and WPPT

    DEFF Research Database (Denmark)

    Cutler, N.; Kay, M.; Jacka, K.

    2007-01-01

    The Wind Power Prediction Tool (WPPT) has been installed in Australia for the first time, to forecast the power output from the 65MW Roaring 40s Renewable Energy P/L Woolnorth Bluff Point wind form. This article analyses the general performance of WPPT as well as its performance during large romps...... (swings) in power output. In addition to this, detected large ramps are studied in detail and categorized. WPPT combines wind speed and direction forecasts from the Australian Bureau of Meteorology regional numerical weather prediction model, MesoLAPS, with real-time wind power observations to make hourly...... forecasts of the wind farm power output. The general performances of MesoLAPS and WPPTore evaluated over I year using the root mean square error (RMSE). The errors are significantly lower than for basic benchmark forecasts but higher than for many other WPPT installations, where the site conditions...

  7. Design of Instantaneous High Power Supply System with power distribution management for portable military devices

    Science.gov (United States)

    Kwak, Kiho; Kwak, Dongmin; Yoon, Joohong

    2015-08-01

    A design of an Instantaneous High Power Supply System (IHPSS) with a power distribution management (PDM) for portable military devices is newly addressed. The system includes a power board and a hybrid battery that can not only supply instantaneous high power but also maintain stable operation at critical low temperature (-30 °C). The power leakage and battery overcharge are effectively prevented by the optimal PDM. The performance of the proposed system under the required pulse loads and the operating conditions of a Korean Advanced Combat Rifle employed in the battlefield is modeled with simulations and verified experimentally. The system with the IHPSS charged the fuse setter with 1.7 times higher voltage (8.6 V) than the one without (5.4 V) under the pulse discharging rate (1 A at 0.5 duty, 1 ms) for 500 ms.

  8. Nuclear science and technology in higher education in the Philippines

    International Nuclear Information System (INIS)

    Bernido, C.C.

    2007-01-01

    Education and training in nuclear science and technology in the Philippines are obtained from higher education institutions, and from courses offered by the Philippine Nuclear Research Institute. The Philippine Nuclear Research Institute (PNRI), an institute under the Department of Science and Technology (DOST), is the sole government agency in charge of matters pertaining to nuclear science and technology, and the regulation of nuclear energy. The PNRI was tasked with fast-tracking nuclear education and information, together with the Department of Education, Culture and Sports (DECS), the Commission on Higher Education (CHED), and some other government agencies which constituted the Subcommittee on Nuclear Power Public Education and Information, by virtue of Executive Order 243 enacted by then President Ramos on May 12, 1995. This Executive Order created the Nuclear Power Steering Committee; the Subcommittee on Nuclear Power Public Education and Information was one of the subcommittees under it. The Nuclear Power Steering Committee was created when the government was again considering the feasibility of the nuclear power option; this Committee had since become inactive because the government has not re-embarked on a nuclear power program. The Philippines had a nuclear power program in the 1970's. The first nuclear power plant was nearing completion when Chernobyl and Three Mile Island happened. Due to the change in political climate and strong anti-nuclear sentiment, the first nuclear power plant had been mothballed. However, there is a possibility for the introduction of nuclear power in the country's projected energy sources by the year 2025. The country has one research reactor, a 3 MW Triga reactor, but at the present time it is not operational and is under extended shutdown. In the event that the Philippines will again implement a nuclear power program, there will be a great need for M.S. and Ph.D. holders in nuclear engineering. There are less than five

  9. Analysis and experimental study of wireless power transfer with HTS coil and copper coil as the intermediate resonators system

    Science.gov (United States)

    Wang, Xiufang; Nie, Xinyi; Liang, Yilang; Lu, Falong; Yan, Zhongming; Wang, Yu

    2017-01-01

    Intermediate resonator (repeater) between transmitter and receiver can significantly increase the distance of wireless power transfer (WPT) and the efficiency of wireless power transfer. The wireless power transfer via strongly coupled magnetic resonances with an high temperature superconducting (HTS) coil and copper coil as intermediate resonators was presented in this paper. The electromagnetic experiment system under different conditions with different repeating coils were simulated by finite element software. The spatial distribution patterns of magnetic induction intensity at different distances were plotted. In this paper, we examined transfer characteristics with HTS repeating coil and copper repeating coil at 77 K and 300 K, respectively. Simulation and experimental results show that HTS and copper repeating coil can effectively enhance the space magnetic induction intensity, which has significant effect on improving the transmission efficiency and lengthening transmission distance. We found that the efficiency and the distance of wireless power transfer system with an HTS coil as repeater is much higher by using of copper coil as repeater.

  10. Community benefits from wind power: a study of UK practice and comparison with leading European countries. Report to the Renewables Advisory Board and the DTI

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    The size and nature of local community benefits from wind power projects in the UK is investigated. These are compared with the benefits in Denmark, Germany, Spain and Ireland where wind power has enjoyed significantly higher rates of development and benefits come within the framework of all wind power projects. Ten wind power projects in the UK are examined and the remaining projects are surveyed. Support mechanisms, public acceptance, planning systems, community involvement (jobs, local income, ownership) in the UK and the other four countries are analysed. Typical community benefits from wind power in the different countries are listed, and recommendations are given.

  11. Felt power explains the link between position power and experienced emotions.

    Science.gov (United States)

    Bombari, Dario; Schmid Mast, Marianne; Bachmann, Manuel

    2017-02-01

    The approach/inhibition theory by Keltner, Gruenfeld, and Anderson (2003) predicts that powerful people should feel more positive and less negative emotions. To date, results of studies investigating this prediction are inconsistent. We fill this gap with four studies in which we investigated the role of different conceptualizations of power: felt power and position power. In Study 1, participants were made to feel more or less powerful and we tested how their felt power was related to different emotional states. In Studies 2, 3, and 4, participants were assigned to either a high or a low power role and engaged in an interaction with a virtual human, after which participants reported on how powerful they felt and the emotions they experienced during the interaction. We meta-analytically combined the results of the four studies and found that felt power was positively related to positive emotions (happiness and serenity) and negatively to negative emotions (fear, anger, and sadness), whereas position power did not show any significant overall relation with any of the emotional states. Importantly, felt power mediated the relationship between position power and emotion. In summary, we show that how powerful a person feels in a given social interaction is the driving force linking the person's position power to his or her emotional states. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  12. Multi-Time Scale Coordinated Scheduling Strategy with Distributed Power Flow Controllers for Minimizing Wind Power Spillage

    Directory of Open Access Journals (Sweden)

    Yi Tang

    2017-11-01

    Full Text Available The inherent variability and randomness of large-scale wind power integration have brought great challenges to power flow control and dispatch. The distributed power flow controller (DPFC has the higher flexibility and capacity in power flow control in the system with wind generation. This paper proposes a multi-time scale coordinated scheduling model with DPFC to minimize wind power spillage. Configuration of DPFCs is initially determined by stochastic method. Afterward, two sequential procedures containing day-head and real-time scales are applied for determining maximum schedulable wind sources, optimal outputs of generating units and operation setting of DPFCs. The generating plan is obtained initially in day-ahead scheduling stage and modified in real-time scheduling model, while considering the uncertainty of wind power and fast operation of DPFC. Numerical simulation results in IEEE-RTS79 system illustrate that wind power is maximum scheduled with the optimal deployment and operation of DPFC, which confirms the applicability and effectiveness of the proposed method.

  13. Dynamics of massless higher spins in the second order in curvatures

    International Nuclear Information System (INIS)

    Vasiliev, M.A.

    1989-08-01

    The consistent equations of motion of interacting fields of all spins s=0,1/2,1...∞ are constructed explicitly to the second order of the expansion in powers of the higher spin strengths. (author). 14 refs

  14. Markov approach to evaluate the availability simulation model for power generation system in a thermal power plant ,

    Directory of Open Access Journals (Sweden)

    Avdhesh Kr. Sharma

    2012-10-01

    Full Text Available In recent years, the availability of power plants has become increasingly important issue in most developed and developing countries. This paper aims to propose a methodology based on Markov approach to evaluate the availability simulation model for power generation system (Turbine in a thermal power plant under realistic working environment. The effects of occurrence of failure/course of actions and availability of repair facilities on system performance have been investigated. Higher availability of the components/equipments is inherently associated with their higher reliability and maintainability. The power generation system consists of five subsystems with four possible states: full working, reduced capacity, reduced efficiency and failed state. So, its availability should be carefully evaluated in order to foresee the performance of the power plant. The availability simulation model (Av. has been developed with the help of mathematical formulation based on Markov Birth-Death process using probabilistic approach. For this purpose, first differential equations have been generated. These equations are then solved using normalizing condition so as to determine the steady state availability of power generation system. In fact, availability analysis is very much effective in finding critical subsystems and deciding their preventive maintenance program for improving availability of the power plant as well as the power supply. From the graphs illustrated, the optimum values of failure/repair rates for maximum availability, of each subsystem is analyzed and then maintenance priorities are decided for all subsystems.The present paper highlights that in this system, Turbine governing subsystem is most sensitive demands more improvement in maintainability as compared to the other subsystems. While Turbine lubrication subsystem is least sensitive.

  15. Opportunities for Combined Heat and Power in Data Centers

    Energy Technology Data Exchange (ETDEWEB)

    Darrow, Ken [ICF International; Hedman, Bruce [ICF International

    2009-03-01

    Data centers represent a rapidly growing and very energy intensive activity in commercial, educational, and government facilities. In the last five years the growth of this sector was the electric power equivalent to seven new coal-fired power plants. Data centers consume 1.5% of the total power in the U.S. Growth over the next five to ten years is expected to require a similar increase in power generation. This energy consumption is concentrated in buildings that are 10-40 times more energy intensive than a typical office building. The sheer size of the market, the concentrated energy consumption per facility, and the tendency of facilities to cluster in 'high-tech' centers all contribute to a potential power infrastructure crisis for the industry. Meeting the energy needs of data centers is a moving target. Computing power is advancing rapidly, which reduces the energy requirements for data centers. A lot of work is going into improving the computing power of servers and other processing equipment. However, this increase in computing power is increasing the power densities of this equipment. While fewer pieces of equipment may be needed to meet a given data processing load, the energy density of a facility designed to house this higher efficiency equipment will be as high as or higher than it is today. In other words, while the data center of the future may have the IT power of ten data centers of today, it is also going to have higher power requirements and higher power densities. This report analyzes the opportunities for CHP technologies to assist primary power in making the data center more cost-effective and energy efficient. Broader application of CHP will lower the demand for electricity from central stations and reduce the pressure on electric transmission and distribution infrastructure. This report is organized into the following sections: (1) Data Center Market Segmentation--the description of the overall size of the market, the size and

  16. Feed-Forward Control of Kite Power Systems

    International Nuclear Information System (INIS)

    Fechner, Uwe; Schmehl, Roland

    2014-01-01

    Kite power technology is a novel solution to harvest wind energy from altitudes that can not be reached by conventional wind turbines. The use of a lightweight but strong tether in place of an expensive tower provides an additional cost advantage, next to the higher capacity factor. This paper describes a method to estimate the wind velocity at the kite using measurement data at the kite and at the ground. Focussing on a kite power system, which is converting the traction power of a kite in a pumping mode of operation, a reel-out speed predictor is presented for use in feed-forward control of the tether reel-out speed of the winch. The results show, that the developed feedforward controller improves the force control accuracy by a factor of two compared to the previously used feedback controller. This allows to use a higher set force during the reel-out phase which in turn increases the average power output by more than 4%. Due to its straightforward implementation and low computational requirements feedforward control is considered a promising technique for the reliable and efficient operation of traction-based kite power systems

  17. Hearing the Voices of Disabled Students in Higher Education

    Science.gov (United States)

    Vickerman, Philip; Blundell, Milly

    2010-01-01

    Since the return of the Labour government to power in the UK in 1997 issues of social inclusion have risen up the political and statutory agenda within higher education (HE). This study reports the findings of disabled students lived experiences and views of transition from induction through to employability within one HE institution. The study…

  18. Higher Inductive Types as Homotopy-Initial Algebras

    Science.gov (United States)

    2016-08-01

    correspondence between Martin -Löf’s constructive type theory and ab- stract homotopy theory. We have a powerful interplay between these disciplines - we can...inductive types we call W-quotients which generalize Martin -Löf’s well-founded trees to a higher- dimensional setting. We have shown that a...27]). Among the most studied type theories is Martin -Löf’s intuition- istic type theory ([20, 22]), also known as constructive or dependent type

  19. Keys to success for wind power in isolated power systems

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, J C; Lundsager, P; Bindner, H; Hansen, L; Frandsen, S [Risoe National Lab., Wind Energy and Atmospheric Physics Dept., Roskilde (Denmark)

    1999-03-01

    It is generally expected that wind power could contribute significantly to the electricity supply in power systems of small and medium sized isolated communities. The market for such applications of wind power has not yet materialized. Wind power in isolated power systems have the main market potentials in developing countries. The money available world-wide for this technological development is limited and the necessary R and D and pilot programmes have difficult conditions. Consequently, technology developed exclusively for developing countries rarely becomes attractive for consumers, investors and funding agencies. A Danish research project is aimed at studying development of methods and guidelines rather than `universal solutions` for the use of wind energy in isolated communities. This paper report on the findings of the project regarding barriers removal and engineering methods development, with a focus on analysis and specification of user demand and priorities, numerical modeling requirements as well as wind power impact on power quality and power system operation. Input will be provided on these subjects for establishing of common guidelines on relevant technical issues, and thereby enabling the making of trustworthy project preparation studies. (au) EFP-97. 12 refs.

  20. Diamond encapsulated photovoltaics for transdermal power delivery.

    Science.gov (United States)

    Ahnood, A; Fox, K E; Apollo, N V; Lohrmann, A; Garrett, D J; Nayagam, D A X; Karle, T; Stacey, A; Abberton, K M; Morrison, W A; Blakers, A; Prawer, S

    2016-03-15

    A safe, compact and robust means of wireless energy transfer across the skin barrier is a key requirement for implantable electronic devices. One possible approach is photovoltaic (PV) energy delivery using optical illumination at near infrared (NIR) wavelengths, to which the skin is highly transparent. In the work presented here, a subcutaneously implantable silicon PV cell, operated in conjunction with an external NIR laser diode, is developed as a power delivery system. The biocompatibility and long-term biostability of the implantable PV is ensured through the use of an hermetic container, comprising a transparent diamond capsule and platinum wire feedthroughs. A wavelength of 980 nm is identified as the optimum operating point based on the PV cell's external quantum efficiency, the skin's transmission spectrum, and the wavelength dependent safe exposure limit of the skin. In bench-top experiments using an external illumination intensity of 0.7 W/cm(2), a peak output power of 2.7 mW is delivered to the implant with an active PV cell dimension of 1.5 × 1.5 × 0.06 mm(3). This corresponds to a volumetric power output density of ~20 mW/mm(3), significantly higher than power densities achievable using inductively coupled coil-based approaches used in other medical implant systems. This approach paves the way for further ministration of bionic implants. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. The Barkas effect and other higher-order Z1-contributions to the stopping power

    International Nuclear Information System (INIS)

    Andersen, H.H.

    1985-01-01

    The experimental evidence for contributions to the stopping power proportional to Z 1 3 (Barkas effect) and Z 1 4 (Bloch correction) at velocities around 10 v 0 is reviewed. Quantitative evidence is found for both terms but it is not possible experimentally to discern whether hard collisions contribute to the Barkas term. Evidence from single-collision events are drawn into the discussion and some experiments which may turn out to be decisive are discussed. (orig.)

  2. Optimum voltage of auxiliary systems for thermal and nuclear power plants

    International Nuclear Information System (INIS)

    Tokumitsu, Iwao; Segawa, Motomichi

    1979-01-01

    In the power plants in Japan, their unit power output has been greatly enhanced since the introduction of new powerful thermal power plants from 1950's to 1960's. In both thermal and nuclear power plants, 1,000 MW machines have been already in operation. The increase of unit power output results in the increase of in-plant load capacity. Of these the voltage adopted for in-plant low voltage systems is now mainly 440 V at load terminals, and the voltage for in-plant high voltage systems has been changing to 6 kV level via 3 kV and 4 kV levels. As plant capacity increases, the load of low voltage systems significantly increases, and it is required to raise the voltage of 400 V level. By the way, the low voltage in AC is specified to be not higher than 600 V. This makes the change within the above range comparatively easy. Considering these conditions, it is recommended to change the voltage for low voltage systems to 575 V at power source terminals and 550 V at load terminals. Some merits in constructing power systems and in economy by raising the voltage were examined. Though demerits are also found, they are only about 15% of total merits. The most advantageous point in raising the voltage is to be capable of increasing the supplying range to low voltage system loads. (Wakatsuki, Y.)

  3. Report of the ASSET (Assessment of Safety Significant Events Team) mission to the Cernavoda nuclear power plant in Romania 8-12 August 1994 Division of Nuclear Safety. Root cause analysis of a significant event that occurred during commissioning of unit 1

    International Nuclear Information System (INIS)

    1994-01-01

    The IAEA Assessment of Safety Significant Events Team (ASSET) report presents the results of the team's investigation of a significant event that occurred during commissioning of Unit 1 of Cernavoda nuclear power plant. The results, conclusions and suggestions presented herein reflect the views of the ASSET experts. They are provided for consideration by the responsible authorities in Romania. The ASSET team's views presented in this report are based on visits to the plant, on review of documentation made available by the operating organization and on discussions with utility personnel. The report is intended to enhance operational safety at Cernavoda by proposing improvements to the policy for the prevention of incidents at the plant. The report includes, as a usual practice, the official response of the Regulatory Body and Operating Organization to the ASSET recommendations. Figs

  4. What if there were no significance tests?

    CERN Document Server

    Harlow, Lisa L; Steiger, James H

    2013-01-01

    This book is the result of a spirited debate stimulated by a recent meeting of the Society of Multivariate Experimental Psychology. Although the viewpoints span a range of perspectives, the overriding theme that emerges states that significance testing may still be useful if supplemented with some or all of the following -- Bayesian logic, caution, confidence intervals, effect sizes and power, other goodness of approximation measures, replication and meta-analysis, sound reasoning, and theory appraisal and corroboration. The book is organized into five general areas. The first presents an overview of significance testing issues that sythesizes the highlights of the remainder of the book. The next discusses the debate in which significance testing should be rejected or retained. The third outlines various methods that may supplement current significance testing procedures. The fourth discusses Bayesian approaches and methods and the use of confidence intervals versus significance tests. The last presents the p...

  5. Significance of Lead Residues in Mallard Tissues

    Science.gov (United States)

    Longcore, J.R.; Locke, L.N.; Bagley, George E.; Andrews, R.

    1974-01-01

    Tissues of adult, lead-dosed mallards that either died or were sacrificed were analyzed for lead. Lead levels in brains, tibiae, and breast muscle of ducks that died and in tibiae of ducks that were sacrificed increased significantly from dosage until death. Lead in the heart, lung, and blood from sacrificed ducks decreased significantly from dosage until death. Lead concentrations in tissues from ducks in the two groups were not significantly different except for the liver, kidney, and lung. Average lead levels in the livers and kidneys of ducks that died were significantly higher than those in ducks that were sacrificed. The mean concentration of lead in the lungs of the ducks sacrificed was significantly higher than the mean level in the lungs of ducks that died. Measurements of the lead concentrations in this study, when compared with lead levels reported in the literature for avian and non-avian species, showed that arbitrary diagnostic levels indicating lead poisoning could be set. In mallard ducks, lead levels exceeding 3 ppm in the brain, 6 to 20 ppm in the kidney or liver, or 10 ppm in clotted blood from the heart indicated acute exposure to lead.

  6. Near-maximum-power-point-operation (nMPPO) design of photovoltaic power generation system

    Energy Technology Data Exchange (ETDEWEB)

    Huang, B.J.; Sun, F.S.; Ho, R.W. [Department of Mechanical Engineering, National Taiwan University, Taipei 106, Taiwan (China)

    2006-08-15

    The present study proposes a PV system design, called 'near-maximum power-point-operation' (nMPPO) that can maintain the performance very close to PV system with MPPT (maximum-power-point tracking) but eliminate hardware of the MPPT. The concept of nMPPO is to match the design of battery bank voltage V{sub set} with the MPP (maximum-power point) of the PV module based on an analysis using meteorological data. Three design methods are used in the present study to determine the optimal V{sub set}. The analytical results show that nMPPO is feasible and the optimal V{sub set} falls in the range 13.2-15.0V for MSX60 PV module. The long-term performance simulation shows that the overall nMPPO efficiency {eta}{sub nMPPO} is higher than 94%. Two outdoor field tests were carried out in the present study to verify the design of nMPPO. The test results for a single PV module (60Wp) indicate that the nMPPO efficiency {eta}{sub nMPPO} is mostly higher than 93% at various PV temperature T{sub pv}. Another long-term field test of 1kWp PV array using nMPPO shows that the power generation using nMPPO is almost identical with MPPT at various weather conditions and T{sub pv} variation from 24{sup o}C to 70{sup o}C. (author)

  7. Rethinking Rectification: AC-DC Power Supply in Package

    DEFF Research Database (Denmark)

    Pejtersen, Jens; Knott, Arnold; Jørgensen, Ivan Harald Holger

    efficiency, while drawing high input peak current with a high harmonic content. Mitigating these non-idealities requires higher order EMI filters and a subsequent power factor correction stage. Advanced active rectifier topologies can mitigate all three non-idealities simultaneously while balancing power...

  8. Nuclear power systems for Lunar and Mars exploration

    International Nuclear Information System (INIS)

    Sovie, R.J.; Bozek, J.M.

    1994-01-01

    Initial studies of a variety of mission scenarios for the new Space Exploration Initiative, and the technologies necessary to enable or significantly enhance them, have identified the development of advanced space power systems - whether solar, chemical or nuclear - to be of prime importance. Lightweight, compact, reliable power systems for planetary rovers and a variety of surface vehicles, utility surface power, and power for advanced propulsion systems were identified as critical needs for these missions. This paper discusses these mission scenarios, the concomitant power system requirements; the power system options considered and identifies the significant potential benefits of nuclear power for meeting the power needs of the above applications

  9. Four-quadrant flyback converter for direct audio power amplification

    OpenAIRE

    Ljusev, Petar; Andersen, Michael Andreas E.

    2005-01-01

    This paper presents a bidirectional, four-quadrant flyback converter for use in direct audio power amplification. When compared to the standard Class-D switching audio power amplifier with a separate power supply, the proposed four-quadrant flyback converter provides simple solution with better efficiency, higher level of integration and lower component count.

  10. On the Physical Significance of Infra-red Corrections to Inflationary Observables

    CERN Document Server

    Bartolo, N; Pietroni, M; Riotto, Antonio; Seery, D

    2008-01-01

    Inflationary observables, like the power spectrum, computed at one- and higher-order loop level seem to be plagued by large infra-red corrections. In this short note, we point out that these large infra-red corrections appear only in quantities which are not directly observable. This is in agreement with general expectations concerning infra-red effects.

  11. Future wind power forecast errors, need for regulating power, and costs in the Swedish system

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, Fredrik [Vattenfall Research and Development AB, Stockholm (Sweden). Power Technology

    2011-07-01

    Wind power is one of the renewable energy sources in the electricity system that grows most rapid in Sweden. There are however two market challenges that need to be addressed with a higher proportion of wind power - that is variability and predictability. Predictability is important since the spot market Nord Pool Spot requires forecasts of production 12 - 36 hours ahead. The forecast errors must be regulated with regulating power, which is expensive for the actors causing the forecast errors. This paper has investigated a number of scenarios with 10 - 55 TWh of wind power installed in the Swedish system. The focus has been on a base scenario with 10 TWh new wind power consisting of 3,5 GW new wind power and 1,5 GW already installed power, which gives 5 GW. The results show that the costs for the forecast errors will increase as more intermittent production is installed. However, the increase can be limited by for instance trading on intraday market or increase quality of forecasts. (orig.)

  12. High-power copper vapour lasers and applications

    Energy Technology Data Exchange (ETDEWEB)

    Chang, J.J.; Warner, B.E.; Boley, C.D.; Dragon, E.P.

    1995-08-01

    Expanded applications of copper vapor lasers has prompted increased demand for higher power and better beam quality. This paper reports recent progress in laser power scaling, MOPA operation, beam quality improvement, and applications in precision laser machining. Issues such as gas heating, radial delay, discharge instability, and window heating will also be discussed.

  13. The development of market power in the Polish power generation sector: A 10-year perspective

    International Nuclear Information System (INIS)

    Kamiński, Jacek

    2012-01-01

    The paper examines how and to which extent consolidation in the Polish power generation sector has affected the potential for market power over the last 10 years. Although this sector has been undergoing liberalisation (privatisation, introduction of TPA regulations and competition etc.), the consolidation efforts shown by Polish governments have resulted in a significant increase in concentration of both installed capacity and production. The methodology applied in this study includes typical ex-post structural and behavioural measures employed to estimate potential for market power, namely: concentration ratios (for the largest and the three largest suppliers), the Herfindahl–Hirschman Index, entropy, Supply Margin Assessment, the Residual Supply Index and the Lerner Index. Furthermore, an analysis based on the Gini coefficient was employed to obtain an insight into inequalities. The results of this study show that governmental decisions led to a significant increase in the potential to exercise market power held by key power generation companies. Of key importance was the 2007 consolidation, resulting in an increase in the HHI to 1374 (in terms of installed capacity) and 1945 (in terms of electricity production). This consolidation resulted in the creation of the first Pivotal Supplier in the Polish power generation sector in 2008. - Highlights: ► Market power analysis based on structural and behavioural indices was carried out for the Polish power sector. ► Governmental policy resulted in significant increase in concentration of both installed capacity and generation. ► Increase in the Lerner Index of brown coal-based generation and decrease of the hard coal-based one were observed.

  14. Improving the Power out of a Piezoelectric Energy Harvester Using Segmented Electrodes

    Directory of Open Access Journals (Sweden)

    SAJID RAFIQUE

    2017-01-01

    Full Text Available Vibration-based EH (Energy Harvesting using piezoelectric materials have been investigated by several research groups with the aim of harvesting maximum energy and providing power to low-powered wireless electronic systems for their entire operational life. The main areas of research includes improvements in mathematical modelling, optimization of harvester geometry, developments in electrical circuitry, advancements in charge storage devices and investigating various piezoelectric materials to achieve maximum power output. This paper investigates and compares the electrical power output with whole length electrodes and with segmentation of electrodes for the same harvester length. It is found that the voltage generated by one electrode of length l/2 of the direction-fixed tip system is significantly greater than that produced by one electrode of length l of the free tip system. This paper also verifies the fact that segmentation of electrodes reduces the effect of strain nodes and charge cancellation particularly at higher mode frequencies. The paper presents the simulation results using DSM (Dynamic Stiffness Matrix which is a compact method of modelling piezoelectric beams

  15. Improving the power out of a piezoelectric energy harvester using segmented electrodes

    International Nuclear Information System (INIS)

    Rafiq, S.; Shah, S.A.

    2017-01-01

    Vibration-based EH (Energy Harvesting) using piezoelectric materials have been investigated by several research groups with the aim of harvesting maximum energy and providing power to low-powered wireless electronic systems for their entire operational life. The main areas of research includes improvements in mathematical modelling, optimization of harvester geometry, developments in electrical circuitry, advancements in charge storage devices and investigating various piezoelectric materials to achieve maximum power output. This paper investigates and compares the electrical power output with whole length electrodes and with segmentation of electrodes for the same harvester length. It is found that the voltage generated by one electrode of length l/2 of the direction-fixed tip system is significantly greater than that produced by one electrode of length l of the free tip system. This paper also verifies the fact that segmentation of electrodes reduces the effect of strain nodes and charge cancellation particularly at higher mode frequencies. The paper presents the simulation results using DSM (Dynamic Stiffness Matrix) which is a compact method of modelling piezoelectric beams. (author)

  16. Independent from muscle power and balance performance, a creatinine clearance below 65 ml/min is a significant and independent risk factor for falls and fall-related fractures in elderly men and women diagnosed with osteoporosis.

    Science.gov (United States)

    Dukas, L; Schacht, E; Runge, M

    2010-07-01

    We assessed in a cross-sectional study in elderly men and women with osteoporosis, the association between the creatinine clearance (CrCl) and the performance in different balance and muscle power and function tests and found that a decreasing creatinine clearance was significantly associated with lower balance and muscle power. To determine if a creatinine clearance of balance and an increased risk for falls and fractures. We assessed in a cross-sectional-study in 1781 German osteoporotic patients, the association between the CrCl, the physical performance, and the number of falls and fractures. Controlling for age, gender, BMI, and osteoporosis treatment (fracture analysis only), a decreasing CrCl was associated with lower physical performance in the timed-up-and-go test (corr -0.2337, P risk for falls (47.7% vs. 36.2%, P = 0.0008) and fall-related fractures (33.1% vs. 22.9%, P = 0.0003) compared with a CrCl of >or=65 ml/min. In this study, we found a significant gender-independent correlation between decreasing CrCl and lower performance in balance and muscle power tests. Reduced muscle power and balance may therefore be involved in the low creatinine clearance associated increased risk for falls and fall-related fractures. Furthermore, we found that a CrCl balance tests, is a significant risk factor for falls and fractures.

  17. Power from triticale straw

    Energy Technology Data Exchange (ETDEWEB)

    Dassanayake, M.; Kumar, A. [Alberta Univ., Edmonton, AB (Canada). Dept. of Mechanical Engineering

    2010-07-01

    This study examined the feasibility of using triticale straw for production of electricity in Canada. Triticale is a manmade hybrid of wheat and rye and it has a high potential of growth in Canada. The cost ($/MWh) of producing electricity from triticale straw was estimated using a data intensive techno-economic model. The study also determined the optimum size of a biomass power plant (MW) which is a trade-off between capital cost of the plant and transportation cost of biomass. Cost curves were also developed in order to evaluate the impact of scale on power production costs. The location of the power plant and the future expansion of triticale were among the factors considered in the techno-economic mode. The scope of the work included all the processes beginning with the collection of straw to the conversion to electricity through direct combustion at the power plant. According to the preliminary results, the cost of producing power from triticale straw is higher than coal-based electricity production in western Canada.

  18. Gas to Power in China. Gas-fired Power in China. Clearing the policy bottleneck

    International Nuclear Information System (INIS)

    Chen, Xavier

    2005-12-01

    Policy for gas-fired power is the single most serious and common issue that needs urgent resolution for all China's current and future gas projects, including LNG projects. This was the main conclusion of a national seminar on gas industry development policy that was held in July 2004. At the time of writing this paper, such a policy is still missing. In order to reduce pollution, improve energy security and meet the needs of the ever-growing economy for high-quality energies, the Chinese government has declared its firm intention to develop a natural gas market. The official target is to develop a gas market of 200 bcm/a by 2020, five times of the current size of around 40 bcm/a. Domestic supply is expected to provide 120 bcm/a, with the rest (80 bcm/a) by gas imports either in the form of piped gas or LNG. Gas-fired power generation plays a critical role in developing a sizeable gas market, especially for large-scale pipeline and LNG projects. Similar to the Guangdong and Fujian LNG projects where gas-fired power accounts for approximately 60% and 70% respectively of the first phase gas volume, each of the proposed LNG projects has allocated a large portion of the gas off-take volume to the power sector. In addition to the first two commercial CCGT plants that were commissioned in 2005, there are over 20 projects totalling 18 GW of capacity under construction. By 2020, China's planners foresee a total gas-fired power capacity of 60 GW, accounting for around 6% of the total installed capacity in the country. Despite these impressive projections, gas-fired power faces significant uncertainties in China: (1) there is an ongoing debate on whether China should develop gas-fired power, given the relative scarcity and higher cost of gas; (2) high gas prices and imported equipment limit the competitiveness of gas-fired power relative to a coal-fired one; (3) it lacks policy support. For the moment, gas-fired power plants are required to participate in a yet

  19. Solar cell power source system

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Yoichi; Toma, Kunio; Fukuwa, Shinji

    1988-05-14

    This invention aims to supply a power source system with stable power output by reducing the power loss due to switching in the voltage stabilization even when the power source is a solar cell with frequent voltage variation. For this purpose, in a solar cell power source system consisting of a solar cell, a storage battery, a switching regulator placed between the storage cell and the load, and a load, arrangement was made that, by judging the input voltage from the storage battery, switch-acting the transistor of the switching regulator, if the input voltage is higher than the specified voltage; is the input voltage is lower than the specified voltage, the transistor is put in a full-on state. By this, the supply voltage can be stabilized even when the voltage fluctuates, and system gets more efficient as the switching loss decreases in the voltage stabilizing means. (1 fig)

  20. Power and environmental assessment

    DEFF Research Database (Denmark)

    Cashmore, Matthew Asa; Richardson, Tim

    2013-01-01

    The significance of politics and power dynamics has long been recognised in environmental assessment (EA) research, but there has not been sustained attention to power, either theoretically or empirically. The aim of this special issue is to encourage the EA community to engage more consistently...