WorldWideScience

Sample records for power subscription strategy

  1. Power Subscription Strategy

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1998-12-21

    This document lays out the Bonneville Power Administration`s Power Subscription Strategy, a process that will enable the people of the Pacific Northwest to share the benefits of the Federal Columbia river Power System after 2001 while retaining those benefits within the region for future generations. The strategy also addresses how those who receive the benefits of the region`s low-cost federal power should share a corresponding measure of the risks. This strategy seeks to implement the subscription concept created by the Comprehensive Review in 1996 through contracts for the sale of power and the distribution of federal power benefits in the deregulated wholesale electricity market. The success of the subscription process is fundamental to BPA`s overall business purpose to provide public benefits to the Northwest through commercially successful businesses.

  2. Power Subscription Strategy: Administrator`s Record of Decision.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration

    1998-12-01

    The Bonneville Power Administration (BPA) has decided to adopt a Power Subscription Strategy for entering into new power sales contracts with its Pacific Northwest customers. The Strategy equitably distributes the electric power generated by the Federal Columbia River Power System (FCRPS) within the framework of existing law. The Power Subscription Strategy addresses the availability of power; describes power products; lays out strategies for pricing, including risk management; and discusses contract elements. In proceeding with this Subscription Strategy, BPA is guided by and committed to the Fish and Wildlife funding Principles for the BPA announced by the Vice President of the US in September 1998. This Record of Decision (ROD) addresses the issues raised by commenters who responded to BPA`s Power Subscription Strategy Proposal during and after the comment period that began with the release of the Proposal on September 18, 1998. The ROD is organized in approximately the same way as the Proposal and the Power Subscription Strategy that BPA developed based on the comments received. Abbreviations of party names used in citations appear in the section just preceding this introduction; a list of all the commenters follows the text of the ROD.

  3. Further Analysis of Boiling Points of Small Molecules, CH[subscript w]F[subscript x]Cl[subscript y]Br[subscript z

    Science.gov (United States)

    Beauchamp, Guy

    2005-01-01

    A study to present specific hypothesis that satisfactorily explain the boiling point of a number of molecules, CH[subscript w]F[subscript x]Cl[subscript y]Br[subscript z] having similar structure, and then analyze the model with the help of multiple linear regression (MLR), a data analysis tool. The MLR analysis was useful in selecting the…

  4. Subscriptions

    African Journals Online (AJOL)

    ₤36.30 less 10% to Subscription Agent (₤32.67 + ₤9.33 Forex charges = ₤42.00 to ISEA, Rhodes University). $57.48 less 10% to Subscription Agent ($51.73 + $18.27 Forex charges = $70.00 to ISEA, Rhodes University). Airmail: Please add a further £9/$16. Africa: Individuals: R230.00 less 10% to Agent - (R 207.00 incl.

  5. Vibrational Spectroscopy of the CCl[subscript 4] v[subscript 1] Mode: Theoretical Prediction of Isotopic Effects

    Science.gov (United States)

    Gaynor, James D.; Wetterer, Anna M.; Cochran, Rea M.; Valente, Edward J.; Mayer, Steven G.

    2015-01-01

    Raman spectroscopy is a powerful experimental technique, yet it is often missing from the undergraduate physical chemistry laboratory curriculum. Tetrachloromethane (CCl[subscript 4]) is the ideal molecule for an introductory vibrational spectroscopy experiment and the symmetric stretch vibration contains fine structure due to isotopic variations…

  6. Vibrational Spectroscopy of the CCI[subscript 4]?[subscript 1] Mode: Effect of Thermally Populated Vibrational States

    Science.gov (United States)

    Gaynor, James D.; Wetterer, Anna M.; Cochran, Rea M.; Valente, Edward J.; Mayer, Steven G.

    2015-01-01

    In our previous article on CCl[subscript 4] in this "Journal," we presented an investigation of the fine structure of the symmetric stretch of carbon tetrachloride (CCl[subscript 4]) due to isotopic variations of chlorine in C[superscript 35]Cl[subscript x][superscript 37]Cl[subscript 4-x]. In this paper, we present an investigation of…

  7. Nitration of Phenols Using Cu(NO[subscript 3])[subscript 2]: Green Chemistry Laboratory Experiment

    Science.gov (United States)

    Yadav, Urvashi; Mande, Hemant; Ghalsasi, Prasanna

    2012-01-01

    An easy-to-complete, microwave-assisted, green chemistry, electrophilic nitration method for phenol using Cu(NO[subscript 3])[subscript 2] in acetic acid is discussed. With this experiment, students clearly understand the mechanism underlying the nitration reaction in one laboratory session. (Contains 4 schemes.)

  8. Subscriptions

    African Journals Online (AJOL)

    Subscriptions Contact. Dr Basil C Ezeanolue Department of Otorhinolaryngology College of Medicine University of Nigeria Teaching Hospital Enugu 400 001. Nigeria Email: editornjorl@yahoo.com. Individuals Nigeria - 600.00 Naira Africa - US$15.00. Other Countries - US$25.00. Institutions Nigeria - 1200.00 Naira

  9. 47 CFR 73.641 - Subscription TV definitions.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Subscription TV definitions. 73.641 Section 73.641 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Television Broadcast Stations § 73.641 Subscription TV definitions. (a) Subscription...

  10. Subscriptions

    African Journals Online (AJOL)

    Subscriptions Contact. Professor Dele Braimoh P.O. Box 392. UNISA 0003. Pretoria South Africa Email: dbraimoh@yahoo.com. The AJCPSF requires a token payment of N5000 (excluding Review fee) from Nigerian and $150 ( International) contributors for maintaining the initial cost of editorial works on submitted articles ...

  11. Subscriptions

    African Journals Online (AJOL)

    US$80 per volume (Institutional) US$45 per volume (Individuals) Single copies: US$35. Southern African Subscriptions: R70 per volume (Institutional) R50 per volume (Individuals) Single copies: R30 European sales from Intervention Press, Castenschioldsvej 7, DK 8270 Hojbjerg, Denmark. E-mail: interven@inet.uni2.dk.

  12. subscription information

    Indian Academy of Sciences (India)

    Administrator

    PROCEEDINGS IN ENGINEERING JOURNAL OF. SCIENCE EDUCATION SADHANA (PROCEEDINGS. ENGINEERING SCIENCES) SUBSCRIPTION JOUR-. NAL OF ASTROPHYSICS AND ASTRONOMY. JOURNAL OF BIOSCIENCES JOURNAL OF. CHEMICAL SCIENCES JOURNAL OF EARTH SYS. No. Journal.

  13. Subscriptions

    African Journals Online (AJOL)

    Subscriptions Contact. Rachel Rege Kenya Agricultural Research Institute, P O Box 57811, Nairobi, KENYA Email: rrege@kari.org. East Africa Kssh 4000; Sterling 40; USA $62; including postage by surface mail. Postage by air mail can be arranged at cost on request. Payments to be made to the Editor, East African ...

  14. L[subscript 1] and L[subscript 2] Spoken Word Processing: Evidence from Divided Attention Paradigm

    Science.gov (United States)

    Shafiee Nahrkhalaji, Saeedeh; Lotfi, Ahmad Reza; Koosha, Mansour

    2016-01-01

    The present study aims to reveal some facts concerning first language (L[subscript 1]) and second language (L[subscript 2]) spoken-word processing in unbalanced proficient bilinguals using behavioral measures. The intention here is to examine the effects of auditory repetition word priming and semantic priming in first and second languages of…

  15. Improved Syntheses and Expanded Analyses of the Enantiomerically Enriched Chiral Cobalt Complexes Co(en)[subscript 3]I[subscript 3] and Co(diNOsar)Br[subscript 3

    Science.gov (United States)

    McClellan, Michael J.; Cass, Marion E.

    2015-01-01

    This communication is a collection of additions and modifications to two previously published classic inorganic synthesis laboratory experiments. The experimental protocol for the synthesis and isolation of enantiomerically enriched ?- (or ?-)Co(en)[subscript 3]I[subscript 3] has been modified to increase reproducibility, yield, and enantiomeric…

  16. Utilization of office computer for journal subscription

    International Nuclear Information System (INIS)

    Yonezawa, Minoru; Shimizu, Tokiyo

    1993-01-01

    Integrated library automation system has been operating in Japan Atomic Energy Research Institute library, which consists of three subsystems for serials control, book acquisition and circulation control. Functions of the serials control subsystem have been improved to reduce the work load of journal subscription work. Subscription price(both in foreign currency and Japanese yen), conversion factor, foreign currency exchange rate are newly introduced as data elements to a master file for automatic calculation and totalization in the system, e.g. conversion of subscription price from foreign currency into Japanese yen. Some kinds of journal lists are also printed out, such as journal subscription list, journal distribution list for each laboratory, etc. (author)

  17. Using a Subscription Agent for E-Journal Management

    Science.gov (United States)

    Grogg, Jill E.

    2010-01-01

    Subscription agents have had to reinvent themselves over the past 15 years as the numbers of print subscriptions have dramatically dwindled. Many libraries have chosen to bypass the subscription agent and its extra fees in favor of dealing directly with the publisher for e-journal and e-journal package procurement and management. Especially in…

  18. Managing Distributed Systems with Smart Subscriptions

    Science.gov (United States)

    Filman, Robert E.; Lee, Diana D.; Swanson, Keith (Technical Monitor)

    2000-01-01

    We describe an event-based, publish-and-subscribe mechanism based on using 'smart subscriptions' to recognize weakly-structured events. We present a hierarchy of subscription languages (propositional, predicate, temporal and agent) and algorithms for efficiently recognizing event matches. This mechanism has been applied to the management of distributed applications.

  19. Optimization Performance of a CO[subscript 2] Pulsed Tuneable Laser

    Science.gov (United States)

    Ribeiro, J. H. F.; Lobo, R. F. M.

    2009-01-01

    In this paper, a procedure is presented that will allow (i) the power and (ii) the energy of a pulsed and tuneable TEA CO[subscript 2] laser to be optimized. This type of laser represents a significant improvement in performance and portability. Combining a pulse mode with a grating tuning facility, it enables us to scan the working wavelength…

  20. OAS :: Email subscriptions

    Science.gov (United States)

    subscriptions Videos Photos Live Webcast Social Media Facebook @oasofficial Facebook Twitter @oas_official Webcast Videos Audios Photos Social Media Facebook Twitter Newsletters Press and Communications Department Rights Actions against Corruption C Children Civil Registry Civil Society Contact Us Culture Cyber

  1. Internet Access from CERN GSM subscriptions

    CERN Multimedia

    IT Department

    2008-01-01

    The data service on GSM subscriptions has been improved, allowing CERN users to access the Internet directly. A CERN GSM subscription with data option now allows you to connect to the Internet from a mobile phone or a PC equipped with a GSM modem. The previous access (CERN intranet) still exists. To get access to the new service, you will find all the information on configurations at: http://cern.ch/gprs The use of this service on the Sunrise network is charged on a flat-rate basis (no extra charge related to the volume of downloaded data). Depending on your CERN subscription type (standard or master), you can also connect to foreign GSM data networks (roaming), but this is strongly discouraged, except where absolutely necessary, due to international roaming charges. Telecom Section, IT/CS

  2. K[subscript a] and K[subscript b] from pH and Conductivity Measurements: A General Chemistry Laboratory Exercise

    Science.gov (United States)

    Nyasulu, Frazier; Moehring, Michael; Arthasery, Phyllis; Barlag, Rebecca

    2011-01-01

    The acid ionization constant, K[subscript a], of acetic acid and the base ionization constant, K[subscript b], of ammonia are determined easily and rapidly using a datalogger, a pH sensor, and a conductivity sensor. To decrease sample preparation time and to minimize waste, sequential aliquots of a concentrated standard are added to a known volume…

  3. CERN Library - Reduction of subscriptions to scientific journals

    CERN Multimedia

    2005-01-01

    The Library Working Group for Acquisitions has identified some scientific journal subscriptions as candidates for cancellation. Although the 2005 budget is unchanged with respect to 2004 thanks to the efforts of the Management, it does not take account of inflation, which for many years has been much higher for scientific literature than the normal cost-of-living index. For 2006, the inflation rate is estimated to be 7-8%. Moreover, the Library does not only intend to compensate for the loss of purchasing power but also to make available some funds to promote new Open Access publishing models. (See Bulletin No.15/2005) The list of candidates can be found on the Library homepage (http://library.cern.ch/). In addition, some subscriptions will be converted to online-only, i.e. CERN will no longer order the print version of certain journals. We invite users to carefully check the list (http://library.cern.ch/). Comments on this proposal should be sent to the WGA Chairman, Rudiger Voss, with a copy to the Hea...

  4. 46 CFR 201.42 - Subscription, authentication of documents.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Subscription, authentication of documents. 201.42 Section 201.42 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION POLICY, PRACTICE AND... Subscription, authentication of documents. (a) Documents filed shall be subscribed: (1) By the person or...

  5. Pricing Strategies for CD-ROM Products.

    Science.gov (United States)

    Rowley, J. E.

    1994-01-01

    Pricing strategies for subscriptions and licenses for CD-ROMs are different for single users and networks. The basic components of pricing strategies are charges for subscription, connect line, display/print, telecommunication, session rate, special commands, and special services. Highlights selected supplier pricing strategies for single users…

  6. 41 CFR 101-25.108 - Multiyear subscriptions for publications.

    Science.gov (United States)

    2010-07-01

    ... for publications. 101-25.108 Section 101-25.108 Public Contracts and Property Management Federal...-GENERAL 25.1-General Policies § 101-25.108 Multiyear subscriptions for publications. Subscriptions for periodicals, newspapers, and other publications for which it is known in advance that a continuing requirement...

  7. Managing without a subscription agent: the experience of doing it yourself

    Directory of Open Access Journals (Sweden)

    Lisa Lovén

    2017-11-01

    Full Text Available In October 2015 Stockholm University Library (SUB decided to no longer use the services of a subscription agent for managing individual journal subscriptions. Instead, SUB has taken a do-it-yourself (DIY approach to subscriptions management and now renews and orders new journals directly from each publisher. In the light of two years of experience, this article discusses the key findings of this new way of working with subscriptions, the differences between the first and second year of renewing directly with publishers and the pros and cons of not using an agent. The article ends with a few recommendations and things for other libraries to consider before making the decision to do without a subscription agent and explains why SUB has decided to continue with the DIY approach. 'Based on a breakout session presented at the 40th UKSG Annual Conference, Harrogate, April 2017 '

  8. Synthesis of "trans"-4,5-Bis-dibenzylaminocyclopent-2-Enone from Furfural Catalyzed by ErCl[subscript 3]·6H[subscript 2]O

    Science.gov (United States)

    Estevão, Mónica S.; Martins, Ricardo J. V.; Alfonso, Carlos A. M.

    2017-01-01

    An experiment exploring the chemistry of the carbonyl group for the one-step synthesis of "trans"-4,5- dibenzylaminocyclopent-2-enone is described. The reaction of furfural and dibenzylamine in the environmentally friendly solvent ethanol and catalyzed by the Lewis acid ErCl[subscript 3]·6H[subscript 2]O afforded the product in high…

  9. Food advertising on children's popular subscription television channels in Australia.

    Science.gov (United States)

    Hebden, Lana; King, Lesley; Chau, Josephine; Kelly, Bridget

    2011-04-01

    Trends on Australian free-to-air television show children continue to be exposed to a disproportionate amount of unhealthy food advertising. This study describes the nature and extent of food marketing on the Australian subscription television channels most popular with children. Advertisements broadcast on the six subscription television channels most popular with children were recorded over four days in February 2009. Advertised foods were coded as core/healthy, non-core/unhealthy or miscellaneous/other, and for persuasive marketing techniques (promotional characters, premium offers and nutrition claims). The majority of foods advertised were non-core (72%), with a mean rate of 0.7 non-core food advertisements broadcast per hour, per channel. The frequency of non-core food advertisements differed significantly across channels. Persuasive techniques were used to advertise non-core foods less frequently than core and miscellaneous foods. Non-core foods make up the majority of foods advertised on children's popular subscription channels. However, Australian children currently view less non-core food advertising on subscription television compared with free-to-air. Unlike free-to-air television, subscription services have the unique opportunity to limit inappropriate food marketing to children, given they are less reliant on advertising revenue. © 2011 The Authors. ANZJPH © 2011 Public Health Association of Australia.

  10. CERN GSM SUBSCRIPTIONS

    CERN Multimedia

    Labo Telecom

    2002-01-01

    AS Division has created a new EDH document for handling all GSM subscription requests and amendments. This procedure will enter force immediately and from now on the Labo Telecom stores will no longer be able to deal with requests submitted on paper forms. Detailed information on the subject can be found here and the Labo Telecom stores will continue to open every day between 11.00 a.m. and 12.00 midday. IT-CS-TEL, Labo Telecom

  11. Regionally Selective Requirement for D[subscript 1]/D[subscript 5] Dopaminergic Neurotransmission in the Medial Prefrontal Cortex in Object-in-Place Associative Recognition Memory

    Science.gov (United States)

    Savalli, Giorgia; Bashir, Zafar I.; Warburton, E. Clea

    2015-01-01

    Object-in-place (OiP) memory is critical for remembering the location in which an object was last encountered and depends conjointly on the medial prefrontal cortex, perirhinal cortex, and hippocampus. Here we examined the role of dopamine D[subscript 1]/D[subscript 5] receptor neurotransmission within these brain regions for OiP memory. Bilateral…

  12. Open Access, Library Subscriptions, and Article Processing Charges

    KAUST Repository

    Vijayakumar, J.K.

    2016-05-01

    Hybrid journals contains articles behind a pay-wall to be subscribed, as well as papers made open access when author pays article processing charge (APC). In such cases, an Institution will end up paying twice and Publishers tend to double-dip. Discussions and pilot models are emerging on pricing options, such as “offset pricing,” [where APCs are adjusted or discounted with subscription costs as vouchers or reductions in next year subscriptions, APCs beyond the subscription costs are modestly capped etc] and thus reduce Institutions’ cost. This presentation will explain different models available and how can we attain a transparent costing structure, where the scholarly community can feel the fairness in Publishers’ pricing mechanisms. Though most of the offset systems are developed through national level or consortium level negotiations, experience of individual institutions, like KAUST that subscribe to large e-journals collections, is important in making right decisions on saving Institutes costs and support openness in scholarly communications.

  13. Open Access, Library Subscriptions, and Article Processing Charges

    KAUST Repository

    Vijayakumar, J.K.; Tamarkin, Molly

    2016-01-01

    Hybrid journals contains articles behind a pay-wall to be subscribed, as well as papers made open access when author pays article processing charge (APC). In such cases, an Institution will end up paying twice and Publishers tend to double-dip. Discussions and pilot models are emerging on pricing options, such as “offset pricing,” [where APCs are adjusted or discounted with subscription costs as vouchers or reductions in next year subscriptions, APCs beyond the subscription costs are modestly capped etc] and thus reduce Institutions’ cost. This presentation will explain different models available and how can we attain a transparent costing structure, where the scholarly community can feel the fairness in Publishers’ pricing mechanisms. Though most of the offset systems are developed through national level or consortium level negotiations, experience of individual institutions, like KAUST that subscribe to large e-journals collections, is important in making right decisions on saving Institutes costs and support openness in scholarly communications.

  14. Open access versus subscription journals: a comparison of scientific impact.

    Science.gov (United States)

    Björk, Bo-Christer; Solomon, David

    2012-07-17

    In the past few years there has been an ongoing debate as to whether the proliferation of open access (OA) publishing would damage the peer review system and put the quality of scientific journal publishing at risk. Our aim was to inform this debate by comparing the scientific impact of OA journals with subscription journals, controlling for journal age, the country of the publisher, discipline and (for OA publishers) their business model. The 2-year impact factors (the average number of citations to the articles in a journal) were used as a proxy for scientific impact. The Directory of Open Access Journals (DOAJ) was used to identify OA journals as well as their business model. Journal age and discipline were obtained from the Ulrich's periodicals directory. Comparisons were performed on the journal level as well as on the article level where the results were weighted by the number of articles published in a journal. A total of 610 OA journals were compared with 7,609 subscription journals using Web of Science citation data while an overlapping set of 1,327 OA journals were compared with 11,124 subscription journals using Scopus data. Overall, average citation rates, both unweighted and weighted for the number of articles per journal, were about 30% higher for subscription journals. However, after controlling for discipline (medicine and health versus other), age of the journal (three time periods) and the location of the publisher (four largest publishing countries versus other countries) the differences largely disappeared in most subcategories except for journals that had been launched prior to 1996. OA journals that fund publishing with article processing charges (APCs) are on average cited more than other OA journals. In medicine and health, OA journals founded in the last 10 years are receiving about as many citations as subscription journals launched during the same period. Our results indicate that OA journals indexed in Web of Science and/or Scopus are

  15. Sustainable funding for biocuration: The Arabidopsis Information Resource (TAIR) as a case study of a subscription-based funding model.

    Science.gov (United States)

    Reiser, Leonore; Berardini, Tanya Z; Li, Donghui; Muller, Robert; Strait, Emily M; Li, Qian; Mezheritsky, Yarik; Vetushko, Andrey; Huala, Eva

    2016-01-01

    Databases and data repositories provide essential functions for the research community by integrating, curating, archiving and otherwise packaging data to facilitate discovery and reuse. Despite their importance, funding for maintenance of these resources is increasingly hard to obtain. Fueled by a desire to find long term, sustainable solutions to database funding, staff from the Arabidopsis Information Resource (TAIR), founded the nonprofit organization, Phoenix Bioinformatics, using TAIR as a test case for user-based funding. Subscription-based funding has been proposed as an alternative to grant funding but its application has been very limited within the nonprofit sector. Our testing of this model indicates that it is a viable option, at least for some databases, and that it is possible to strike a balance that maximizes access while still incentivizing subscriptions. One year after transitioning to subscription support, TAIR is self-sustaining and Phoenix is poised to expand and support additional resources that wish to incorporate user-based funding strategies. Database URL: www.arabidopsis.org. © The Author(s) 2016. Published by Oxford University Press.

  16. Evaluation of Maximal O[subscript 2] Uptake with Undergraduate Students at the University of La Reunion

    Science.gov (United States)

    Tarnus, Evelyne; Catan, Aurelie; Verkindt, Chantal; Bourdon, Emmanuel

    2011-01-01

    The maximal rate of O[subscript 2] consumption (VO[subscript 2max]) constitutes one of the oldest fitness indexes established for the measure of cardiorespiratory fitness and aerobic performance. Procedures have been developed in which VO[subscript 2max]is estimated from physiological responses during submaximal exercise. Generally, VO[subscript…

  17. 11 CFR 100.111 - Gift, subscription, loan, advance or deposit of money.

    Science.gov (United States)

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Gift, subscription, loan, advance or deposit of... DEFINITIONS (2 U.S.C. 431) Definition of Expenditure (2 U.S.C. 431(9)) § 100.111 Gift, subscription, loan, advance or deposit of money. (a) A purchase, payment, distribution, loan (except for a loan made in...

  18. Data-Driven Transition: Joint Reporting of Subscription Expenditure and Publication Costs

    Directory of Open Access Journals (Sweden)

    Irene Barbers

    2018-04-01

    Full Text Available The transition process from the subscription model to the open access model in the world of scholarly publishing brings a variety of challenges to libraries. Within this evolving landscape, the present article takes a focus on budget control for both subscription and publication expenditure with the opportunity to enable the shift from one to the other. To reach informed decisions with a solid base of data to be used in negotiations with publishers, the diverse already-existing systems for managing publications costs and for managing journal subscriptions have to be adapted to allow comprehensive reporting on publication expenditure and subscription expenditure. In the case presented here, two separate systems are described and the establishment of joint reporting covering both these systems is introduced. Some of the results of joint reporting are presented as an example of how such a comprehensive monitoring can support management decisions and negotiations. On a larger scale, the establishment of the National Open Access Monitor in Germany is introduced, bringing together a diverse range of data from several already-existing systems, including, among others, holdings information, usage data, and data on publication fees. This system will enable libraries to access all relevant data with a single user interface.

  19. Global and regional emissions estimates of 1,1-difluoroethane (HFC-152a, CH[subscript 3]CHF[subscript 2]) from in situ and air archive observations

    OpenAIRE

    Prinn, Ronald G.

    2015-01-01

    High frequency, in situ observations from 11 globally distributed sites for the period 1994–2014 and archived air measurements dating from 1978 onward have been used to determine the global growth rate of 1,1-difluoroethane (HFC-152a, CH[subscript 3]CHF[subscript 2]). These observations have been combined with a range of atmospheric transport models to derive global emission estimates in a top-down approach. HFC-152a is a greenhouse gas with a short atmospheric lifetime of about 1.5 years. Si...

  20. 47 CFR 73.642 - Subscription TV service.

    Science.gov (United States)

    2010-10-01

    ... expressed or implied, that: (1) Prevents or hinders it from rejecting or refusing any subscription TV..., service may be terminated. (ii) Charges, terms and conditions of service to subscribers must be applied... impositions of different sets of terms and conditions may be applied to subscribers in different...

  1. Synthesis and Characterization of a Perovskite Barium Zirconate (BaZrO[subscript 3]): An Experiment for an Advanced Inorganic Chemistry Laboratory

    Science.gov (United States)

    Thananatthanachon, Todsapon

    2016-01-01

    In this experiment, the students explore the synthesis of a crystalline solid-state material, barium zirconate (BaZrO3) by two different synthetic methods: (a) the wet chemical method using BaCl[subscript 2]·2H[subscript 2]O and ZrOCl[subscript 2]·8H[subscript 2]O as the precursors, and (b) the solid-state reaction from BaCO[subscript 3] and…

  2. mRNA and Protein Levels for GABA[subscript A][alpha]4, [alpha]5, [beta]1 and GABA[subscript B]R1 Receptors are Altered in Brains from Subjects with Autism

    Science.gov (United States)

    Fatemi, S. Hossein; Reutiman, Teri J.; Folsom, Timothy D.; Rooney, Robert J.; Patel, Diven H.; Thuras, Paul D.

    2010-01-01

    We have shown altered expression of gamma-aminobutyric acid A (GABA[subscript A]) and gamma-aminobutyric acid B (GABA[subscript B]) receptors in the brains of subjects with autism. In the current study, we sought to verify our western blotting data for GABBR1 via qRT-PCR and to expand our previous work to measure mRNA and protein levels of 3…

  3. The power of strategy metaphors

    DEFF Research Database (Denmark)

    Lystbæk, Christian Tang; Holmgren, Jens

    2016-01-01

    and post-structuralism. The paper reports on an action research study of a strategy workshop with the strategic team of a Human Resource Management Department in a Danish Municipality. It identifies two structural dimensions and four generic spatial metaphors were identified. Thus, the paper shows......This paper explores the power of spatial metaphors in strategy making. I seek to unfold a conception of the power of spatial metaphors in strategy making that stresses their creative and critical capacity as well as their constraints on strategic thinking. In order to identify the power of spatial...

  4. New types of subscriptions for CERN GSM

    CERN Multimedia

    IT Department

    2010-01-01

    A recent renegotiation of our commercial conditions with our mobile telephony operator allows us today to deploy new GSM mobile services, reduce communication costs, as well as put in place a new subscription system. First of all, the "email to SMS" service has already been extended to all Swiss numbers. This service allows you to send SMS messages (Short Message Service) to any Swiss mobile telephone from your CERN e-mail account. For further details, please refer to the web site http://cern.ch/sms. The sending of MMS messages (Multi-media Message Service) will be activated by default on all CERN subscriptions by the end of March 2010. This service allows users to attach to a text message an image, a video or an audio recording. All the necessary details for configuring this new service on CERN mobile phones will be published on the web site http://cern.ch/mms. Concerning mobile service costs, new rates have been put in place since 1st January 2010. All tariffs have dramatically decrea...

  5. Anon-Pass: Practical Anonymous Subscriptions.

    Science.gov (United States)

    Lee, Michael Z; Dunn, Alan M; Katz, Jonathan; Waters, Brent; Witchel, Emmett

    2013-12-31

    We present the design, security proof, and implementation of an anonymous subscription service. Users register for the service by providing some form of identity, which might or might not be linked to a real-world identity such as a credit card, a web login, or a public key. A user logs on to the system by presenting a credential derived from information received at registration. Each credential allows only a single login in any authentication window, or epoch . Logins are anonymous in the sense that the service cannot distinguish which user is logging in any better than random guessing. This implies unlinkability of a user across different logins. We find that a central tension in an anonymous subscription service is the service provider's desire for a long epoch (to reduce server-side computation) versus users' desire for a short epoch (so they can repeatedly "re-anonymize" their sessions). We balance this tension by having short epochs, but adding an efficient operation for clients who do not need unlinkability to cheaply re-authenticate themselves for the next time period. We measure performance of a research prototype of our protocol that allows an independent service to offer anonymous access to existing services. We implement a music service, an Android-based subway-pass application, and a web proxy, and show that adding anonymity adds minimal client latency and only requires 33 KB of server memory per active user.

  6. An ecological solution in power development strategy: hydroelectric Power

    International Nuclear Information System (INIS)

    Ionescu, S.; Teodorescu, D.

    1994-01-01

    One of the fundamental criteria in establishing the power development strategy is represented by the environmental protection. Besides increasing the power efficiency for users, the hydro power stands for a handy alternative to generate thermal power. Comparatively, if hydro power is properly planed and developed, it could allow conservation of fossil fuel resources (as it makes use of a renewable resources) and avoids air and water pollution and in addition would lead to certain positive effects upon the natural and anthropic environment (flood routing, optimizes the power supply-demand relationship, and so on). By making use of the data available in the international specific literature and the information on the power development strategy in Romania the effects incurred by hydro power are both qualitatively and quantitatively emphasized as compared to alternative power generation by fossil fuel combustion. The proposal is made to adopt certain law regulations as well as a methodology to evaluate the general efficiency of various types of power generating devices suiting the particular conditions of Romania and taking into account the social cost as well as environmental effects. Hence a power development strategy could be undertaking at the national level provided it meets the requirements of both power system and environment protection. (Author)

  7. An Experiment Illustrating the Change in Ligand p"K"[subscript a] upon Protein Binding

    Science.gov (United States)

    Chenprakhon, Pirom; Panijpan, Bhinyo; Chaiyen, Pimchai

    2012-01-01

    The modulation of ligand p"K"[subscript a] due to its surrounding environment is a crucial feature that controls many biological phenomena. For example, the shift in the p"K"[subscript a] of substrates or catalytic residues at enzyme active sites upon substrate binding often triggers and controls enzymatic reactions. In this work, we developed an…

  8. Olfactory Bulb [alpha][subscript 2]-Adrenoceptor Activation Promotes Rat Pup Odor-Preference Learning via a cAMP-Independent Mechanism

    Science.gov (United States)

    Shakhawat, Amin MD.; Harley, Carolyn W.; Yuan, Qi

    2012-01-01

    In this study, three lines of evidence suggest a role for [alpha][subscript 2]-adrenoreceptors in rat pup odor-preference learning: olfactory bulb infusions of the [alpha][subscript 2]-antagonist, yohimbine, prevents learning; the [alpha][subscript 2]-agonist, clonidine, paired with odor, induces learning; and subthreshold clonidine paired with…

  9. price list 2015.pdf | Subscription | Journals | Resources | public ...

    Indian Academy of Sciences (India)

    Home; public; Resources; Journals; Subscription; price list 2015.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. 29th Mid-year meeting. Posted on 19 January 2018. The 29th Mid-year ...

  10. How Einstein Discovered "E[subscript 0] = mc[squared]"

    Science.gov (United States)

    Hecht, Eugene

    2012-01-01

    This paper traces Einstein's discovery of "the equivalence of mass [m] and energy ["E[subscript 0]"]." He came to that splendid insight in 1905 while employed by the Bern Patent Office, at which time he was not an especially ardent reader of physics journals. How then did the young savant, working outside of academia in semi-isolation, realize…

  11. Nuclear power development strategy through 2020 in China

    International Nuclear Information System (INIS)

    Wang Yongping; Zhao Shoufeng; Yuan Yujun; Rao Shuang; Liu Qun; Ding Ruijie

    2005-10-01

    Through the analysis of the nuclear power situation of China, it is emphasized that the nuclear power development strategy is an important part of electric power development strategy and national energy security strategy in China, but nuclear power development in accelerant way will face greater challenge. The uranium demand and supply, the treatment and disposal of radioactive wastes, and other primary problems through 2020 in China are discussed. The nuclear power development strategy till 2020 are described. The relevant measures and recommendations are proposed. (authors)

  12. Energy security strategy and nuclear power

    International Nuclear Information System (INIS)

    Toichi, Tsutomu; Shibata, Masaharu; Uchiyama, Yoji; Suzuki, Tatsujiro; Yamazaki, Kazuo

    2006-01-01

    This special edition of 'Energy security strategy and nuclear power' is abstracts of the 27 th Policy Recommendations 'The Establishment of an International Energy Security System' by the Japan Forum on International Relations, Inc on May 18 th , 2006. It consists of five papers: Energy security trend in the world and Japan strategy by Tsutomu Toichi, Establishment of energy strategy supporting Japan as the focus on energy security by Masaharu Shibata, World pays attention to Japan nuclear power policy and nuclear fuel cycle by Yoji Uchiyama, Part of nuclear power in the energy security - the basic approach and future problems by Tatsujiro Suzuki, and Drawing up the energy strategy focused on the national interests - a demand for the next government by Kazuo Yamazaki. (S.Y.)

  13. 29 CFR 1905.7 - Form of documents; subscription; copies.

    Science.gov (United States)

    2010-07-01

    ... UNDER THE WILLIAMS-STEIGER OCCUPATIONAL SAFETY AND HEALTH ACT OF 1970 General § 1905.7 Form of documents... 29 Labor 5 2010-07-01 2010-07-01 false Form of documents; subscription; copies. 1905.7 Section 1905.7 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION...

  14. Immunoassay for Visualization of Protein-Protein Interactions on Ni-Nitrilotriacetate Support: Example of a Laboratory Exercise with Recombinant Heterotrimeric G[alpha][subscript i2][beta][subscript 1[gamma]2] Tagged by Hexahistidine from sf9 Cells

    Science.gov (United States)

    Bavec, Aljosa

    2004-01-01

    We have developed an "in vitro assay" for following the interaction between the [alpha][subscript i2] subunit and [beta][subscript 1[gamma]2] dimer from sf9 cells. This method is suitable for education purposes because it is easy, reliable, nonexpensive, can be applied for a big class of 20 students, and avoid the commonly used kinetic approach,…

  15. The Essence Of Government Shares Subscription A Review The Implementation Of State-Owned Enterprises

    Directory of Open Access Journals (Sweden)

    Urbanisasi

    2015-08-01

    Full Text Available The purpose of this study was to determine and explain the mechanisms and the implementation of government share subscription in the implementation of SOEs legal standing of the government shares subscription in the implementation of the state budget that separated in the implementation of SOEs and its legal implications of state loss or not and also legal accountability for losses arising out of shares subscription of SOE. In this study the authors use normative legal research. The data obtained in this study will be analyzed using qualitative normative method with inductive logic. Results from the study indicate that state shares subscription in the establishment of SOE or limited company with funds derived from State Budget are separated. Thus the government no longer has any authority in the field of civil law as a business entity. A clear separation of the status of country as business and as government organizer carries consequences. With the separation then there is clarity about the concept of the state financial losses. SOE as one form of business entity that aim to make a profit is a separate legal entity and has responsibilities that are separately anyway though formed and capital originating from the state finances and the loss of one transaction or in legal entity cannot be categorized as a state finance loss because the state has functioned as a private legal entity.

  16. Optimized Power Dispatch Strategy for Offshore Wind Farms

    DEFF Research Database (Denmark)

    Hou, Peng; Hu, Weihao; Zhang, Baohua

    2016-01-01

    which are related to electrical system topology. This paper proposed an optimized power dispatch strategy (OPD) for minimizing the levelized production cost (LPC) of a wind farm. Particle swarm optimization (PSO) is employed to obtain final solution for the optimization problem. Both regular shape......Maximizing the power production of offshore wind farms using proper control strategy has become an important issue for wind farm operators. However, the power transmitted to the onshore substation (OS) is not only related to the power production of each wind turbine (WT) but also the power losses...... and irregular shape wind farm are chosen for the case study. The proposed dispatch strategy is compared with two other control strategies. The simulation results show the effectiveness of the proposed strategy....

  17. GRID[subscript C] Renewable Energy Data Streaming into Classrooms

    Science.gov (United States)

    DeLuca, V. William; Carpenter, Pam; Lari, Nasim

    2010-01-01

    For years, researchers have shown the value of using real-world data to enhance instruction in mathematics, science, and social studies. In an effort to help develop students' higher-order thinking skills in a data-rich learning environment, Green Research for Incorporating Data in the Classroom (GRID[subscript C]), a National Science…

  18. Strategies for growth of thermal power

    International Nuclear Information System (INIS)

    Shah, R.K.D.

    1998-01-01

    The power generating industry in India is at the cross roads. Massive investments are required to achieve GDP growth of 7-8% per annum over the next 10 years. For this, appropriate strategies have to be evolved which will give the country best returns. With coal being the major fuel resource in India, thermal power generation will continue to be the mainstay in the next decade. This paper covers various key issues to be addressed covering the plan and perspectives of thermal power, environmental issues, technology strategies for growth, power policy and R and D. (author)

  19. Killeen's (2005) "p[subscript rep]" Coefficient: Logical and Mathematical Problems

    Science.gov (United States)

    Maraun, Michael; Gabriel, Stephanie

    2010-01-01

    In his article, "An Alternative to Null-Hypothesis Significance Tests," Killeen (2005) urged the discipline to abandon the practice of "p[subscript obs]"-based null hypothesis testing and to quantify the signal-to-noise characteristics of experimental outcomes with replication probabilities. He described the coefficient that he…

  20. National strategy of nuclear power intellectual property

    International Nuclear Information System (INIS)

    Bo Huaitao

    2008-01-01

    The IP strategy includes four strategic levels: international level, national level, industry level and enterprise level. The national nuclear power IP strategy is an industry level strategy, which is also one part of national IP strategy, permeating with the IP strategy of the international level and enterprise level mutually. Commencing from the angles of the national level and the industry level, the author tries to provide a reference for IP strategy by an initial study about IP strategy in nuclear power industry.. The author holds that independent innovation is at the root of strategic establishment; enterprise is the main body for strategic implementation; and evaluating index must be consummated in the strategic evaluation. (authors)

  1. Axial power deviation control strategy and computer simulation for Daya Bay Nuclear Power Station

    International Nuclear Information System (INIS)

    Liao Yehong; Zhou Xiaoling, Xiao Min

    2004-01-01

    Daya Bay Nuclear Power Station has very tight operation diagram especially at its right side. Therefore the successful control of axial power deviation for PWR is crucial to nuclear safety. After analyzing various core characters' effect on axial power distribution, several axial power deviation control strategies has been proposed to comply with different power varying operation scenario. Application and computer simulation of the strategies has shown that our prediction of axial power deviation evolution are comparable to the measurement values, and that our control strategies are effective. Engineering experience shows that the application of our methodology can predict accurately the transient of axial power deviation, and therefore has become a useful tool for reactor operation and safety control. This paper presents the axial power control characteristics, reactor operation strategy research, computer simulation, and comparison to measurement results in Daya Bay Nuclear Power Station. (author)

  2. Evaluation of Advanced Data Centre Power Management Strategies

    NARCIS (Netherlands)

    Postema, Björn F.; Haverkort, Boudewijn R.

    2018-01-01

    In recent work, we proposed a new specification language for power management strategies as an extension to our AnyLogic-based simulation framework for the trade-off analysis of power and performance in data centres. In this paper, we study the quality of such advanced power management strategies

  3. Blockade of IP[subscript 3]-Mediated SK Channel Signaling in the Rat Medial Prefrontal Cortex Improves Spatial Working Memory

    Science.gov (United States)

    Brennan, Avis R.; Dolinsky, Beth; Vu, Mai-Anh T.; Stanley, Marion; Yeckel, Mark F.; Arnsten, Amy F. T.

    2008-01-01

    Planning and directing thought and behavior require the working memory (WM) functions of prefrontal cortex. WM is compromised by stress, which activates phosphatidylinositol (PI)-mediated IP[subscript 3]-PKC intracellular signaling. PKC overactivation impairs WM operations and in vitro studies indicate that IP[subscript 3] receptor (IP[subscript…

  4. Study on emergency power control strategy for AC/DC hybrid power system containing VSC-HVDC

    Science.gov (United States)

    Liu, Lin; Hu, Zhenda; Ye, Rong; Lin, Zhangsui; Yang, Xiaodong; Yi, Yang

    2018-04-01

    This paper presents a comprehensive emergency power control strategy for AC/DC hybrid power systems containing VSC-HVDC. Firstly, the paper analyzes the power support of the VSC-HVDC to the AC lines using the Power Transferring Relativity Factor (PTRF). Then the power adjustment of the VSC-HVDC in several different circumstances are calculated. Finally, the online power control strategies of VSC-HVDC are designed, which could rapidly control the power of the VSC-HVDC, keeping the power flow of AC lines below the upper limit. Furthermore, the strategy is proven to be effective by the simulations with EMTDC/PSCAD.

  5. Measurement of Levitation Forces of High-"T[subscript c] Superconductors

    Science.gov (United States)

    Becker, M.; Koblischka, M. R.; Hartmann, U.

    2010-01-01

    We show the construction of a so-called levitation balance which is capable of measuring the levitation forces between a permanent magnet and a superconducting high-T[subscript c] thin film sample. The underlying theoretical basis is discussed in detail. The experiment is performed as an introductory physics experiment for school students as well…

  6. Extending the Mertonian Norms: Scientists' Subscription to Norms of Research

    Science.gov (United States)

    Anderson, Melissa S.; Ronning, Emily A.; De Vries, Raymond; Martinson, Brian C.

    2010-01-01

    This analysis, based on focus groups and a national survey, assesses scientists' subscription to the Mertonian norms of science and associated counternorms. It also supports extension of these norms to governance (as opposed to administration), as a norm of decision-making, and quality (as opposed to quantity), as an evaluative norm. (Contains 1…

  7. Using a Spreadsheet to Solve the Schro¨dinger Equations for the Energies of the Ground Electronic State and the Two Lowest Excited States of H[subscript2

    Science.gov (United States)

    Ge, Yingbin; Rittenhouse, Robert C.; Buchanan, Jacob C.; Livingston, Benjamin

    2014-01-01

    We have designed an exercise suitable for a lab or project in an undergraduate physical chemistry course that creates a Microsoft Excel spreadsheet to calculate the energy of the S[subscript 0] ground electronic state and the S[subscript 1] and T[subscript 1] excited states of H[subscript 2]. The spreadsheet calculations circumvent the…

  8. Axial power difference control strategy and computer simulation for GNPS during stretch-out and power decrease

    International Nuclear Information System (INIS)

    Liao Yehong; Xiao Min; Li Xianfeng; Zhu Minhong

    2004-01-01

    Successful control of the axial power difference for PWR is crucial to nuclear safety. After analyzing various elements' effect on the axial power distribution, different axial power deviation control strategies have been proposed to comply with different power decrease scenarios. Application of the strategy to computer simulation shows that our prediction of axial power deviation evolution is comparable to the measurement value, and that our control strategy is effective

  9. An improved AVC strategy applied in distributed wind power system

    Science.gov (United States)

    Zhao, Y. N.; Liu, Q. H.; Song, S. Y.; Mao, W.

    2016-08-01

    Traditional AVC strategy is mainly used in wind farm and only concerns about grid connection point, which is not suitable for distributed wind power system. Therefore, this paper comes up with an improved AVC strategy applied in distributed wind power system. The strategy takes all nodes of distribution network into consideration and chooses the node having the most serious voltage deviation as control point to calculate the reactive power reference. In addition, distribution principles can be divided into two conditions: when wind generators access to network on single node, the reactive power reference is distributed according to reactive power capacity; when wind generators access to network on multi-node, the reference is distributed according to sensitivity. Simulation results show the correctness and reliability of the strategy. Compared with traditional control strategy, the strategy described in this paper can make full use of generators reactive power output ability according to the distribution network voltage condition and improve the distribution network voltage level effectively.

  10. Downregulation of GABA[Subscript A] Receptor Protein Subunits a6, ß2, d, e, ?2, ?, and ?2 in Superior Frontal Cortex of Subjects with Autism

    Science.gov (United States)

    Fatemi, S. Hossein; Reutiman, Teri J.; Folsom, Timothy D.; Rustan, Oyvind G.; Rooney, Robert J.; Thuras, Paul D.

    2014-01-01

    We measured protein and mRNA levels for nine gamma-aminobutyric acid A (GABA[subscript A]) receptor subunits in three brain regions (cerebellum, superior frontal cortex, and parietal cortex) in subjects with autism versus matched controls. We observed changes in mRNA for a number of GABA[subscript A] and GABA[subscript B] subunits and overall…

  11. Alternative evacuation strategies for nuclear power accidents

    International Nuclear Information System (INIS)

    Hammond, Gregory D.; Bier, Vicki M.

    2015-01-01

    In the U.S., current protective-action strategies to safeguard the public following a nuclear power accident have remained largely unchanged since their implementation in the early 1980s. In the past thirty years, new technologies have been introduced, allowing faster computations, better modeling of predicted radiological consequences, and improved accident mapping using geographic information systems (GIS). Utilizing these new technologies, we evaluate the efficacy of alternative strategies, called adaptive protective action zones (APAZs), that use site-specific and event-specific data to dynamically determine evacuation boundaries with simple heuristics in order to better inform protective action decisions (rather than relying on pre-event regulatory bright lines). Several candidate APAZs were developed and then compared to the Nuclear Regulatory Commission’s keyhole evacuation strategy (and full evacuation of the emergency planning zone). Two of the APAZs were better on average than existing NRC strategies at reducing either the radiological exposure, the population evacuated, or both. These APAZs are especially effective for larger radioactive plumes and at high population sites; one of them is better at reducing radiation exposure, while the other is better at reducing the size of the population evacuated. - Highlights: • Developed framework to compare nuclear power accident evacuation strategies. • Evacuation strategies were compared on basis of radiological and evacuation risk. • Current strategies are adequate for smaller scale nuclear power accidents. • New strategies reduced radiation exposure and evacuation size for larger accidents

  12. Simplified reactive power management strategy for complex power grids under stochastic operation and incomplete information

    International Nuclear Information System (INIS)

    Vlachogiannis, John G.

    2009-01-01

    In the current released energy market, the large-scale complex transmission networks and the distribution ones with dispersed energy sources and 'intelligent' components operate under uncertainties, stochastic and prior incomplete information. A safe and reliable operation of such complex power grids is a major issue for system operators. Under these circumstances an online reactive power management strategy with minimum risk concerning all uncertain and stochastic parameters is proposed. Therefore, new concepts such as reactive power-weighted node-to-node linking and reactive power control capability are introduced. A distributed and interconnected stochastic learning automata system is implemented to manage, in a unified and unique way, the reactive power in complex power grids with stochastic reactive power demand and detect the vulnerable part. The proposed simplified strategy can also consider more stochastic aspects such as variable grid's topology. Results of the proposed strategy obtained on the networks of IEEE 30-bus and IEEE 118-bus systems demonstrate the effectiveness of the proposed strategy.

  13. [Reading behavior and preferences regarding subscriptions to scientific journals : Results of a survey of members of the German Society for General and Visceral Surgery].

    Science.gov (United States)

    Ronellenfitsch, U; Klinger, C; Buhr, H J; Post, S

    2015-11-01

    The purpose of surgical literature is to publish the latest study results and to provide continuing medical education to readers. For optimal allocation of resources, institutional subscribers, professional societies and scientific publishers require structured data on reading and subscription preferences of potential readers of surgical literature. To obtain representative data on the preferences of German general and visceral surgeons regarding reading of and subscription to scientific journals. All members of the German Society for General and Visceral Surgery (DGAV) were invited to participate in a web-based survey. Questions were asked on the affiliation and position of the member, individual journal subscriptions, institutional access to scientific journals, preferences regarding electronic or print articles and special subscriptions for society members. Answers were descriptively analyzed. A total of 630 out of 4091 (15 %) members participated in the survey and 73 % of the respondents had at least 1 individual subscription to a scientific journal. The most frequently subscribed journal was Der Chirurg (47 % of respondents). The institutional access to journals was deemed insufficient by 48 % of respondents, predominantly in primary care hospitals and outpatient clinics. Almost half of the respondents gave sufficient importance to reading printed versions of articles for which they would pay extra fees. A group subscription for society members was perceived as advantageous as long as no relevant extra costs were incurred. This structured survey among members of the DGAV provides data on preferences regarding reading of and subscription to scientific journals. Individual subscriptions to journals are still common, possibly due to suboptimal institutional access particularly at smaller non-academic institutions. In an age of online publications it seems surprising that many respondents place a high value on printed versions. The results are relevant for

  14. Iran's Sea Power Strategy: Goals and Evolution

    National Research Council Canada - National Science Library

    Walker, John

    1997-01-01

    This thesis examines the intent of Iran's sea power strategy using a multipart analysis including a historical review of the transition of Iran's naval power through the Iranian Revolution, Iran-Iraq...

  15. Power supply strategy in Lithuania

    International Nuclear Information System (INIS)

    Galinis, A.

    2000-01-01

    Nuclear power plant produces about 80% of electricity in Lithuania. However, national energy strategy as a result of comprehensive assessment of technical, economic and political factors foresees closure of its first unit by 2005. Future fate of the second unit will be defined later in 2004 . Electricity demand requirements will be covered by other modernised power plants burning fossil fuel. This may create some environmental problems, especially if unit 2 would be closed. Earlier closure of the nuclear power plant is a great economical burden not only for the power sector but also to the whole national economy. This requires substantial technical and financial support from EU and other developed countries. (author)

  16. Specification of data centre power management strategies

    NARCIS (Netherlands)

    Postema, Björn F.; Haverkort, Boudewijn R.

    2017-01-01

    In recent work, we proposed a flexible simulation framework (using AnyLogic) for the trade-off. analysis of power and performance in data centres. We now extend this framework with a versatile module to study the effect of advanced power management strategies based on both power and performance

  17. How Often Is p[subscript rep] Close to the True Replication Probability?

    Science.gov (United States)

    Trafimow, David; MacDonald, Justin A.; Rice, Stephen; Clason, Dennis L.

    2010-01-01

    Largely due to dissatisfaction with the standard null hypothesis significance testing procedure, researchers have begun to consider alternatives. For example, Killeen (2005a) has argued that researchers should calculate p[subscript rep] that is purported to indicate the probability that, if the experiment in question were replicated, the obtained…

  18. Bidding Strategy of Virtual Power Plant with Energy Storage Power Station and Photovoltaic and Wind Power

    Directory of Open Access Journals (Sweden)

    Zhongfu Tan

    2018-01-01

    Full Text Available For the virtual power plants containing energy storage power stations and photovoltaic and wind power, the output of PV and wind power is uncertain and virtual power plants must consider this uncertainty when they participate in the auction in the electricity market. In this context, this paper studies the bidding strategy of the virtual power plant with photovoltaic and wind power. Assuming that the upper and lower limits of the combined output of photovoltaic and wind power are stochastically variable, the fluctuation range of the day-ahead energy market and capacity price is stochastically variable. If the capacity of the storage station is large enough to stabilize the fluctuation of the output of the wind and photovoltaic power, virtual power plants can participate in the electricity market bidding. This paper constructs a robust optimization model of virtual power plant bidding strategy in the electricity market, which considers the cost of charge and discharge of energy storage power station and transmission congestion. The model proposed in this paper is solved by CPLEX; the example results show that the model is reasonable and the method is valid.

  19. Generating optimized stochastic power management strategies for electric car components

    Energy Technology Data Exchange (ETDEWEB)

    Fruth, Matthias [TraceTronic GmbH, Dresden (Germany); Bastian, Steve [Technische Univ. Dresden (Germany)

    2012-11-01

    With the increasing prevalence of electric vehicles, reducing the power consumption of car components becomes a necessity. For the example of a novel traffic-light assistance system, which makes speed recommendations based on the expected length of red-light phases, power-management strategies are used to control under which conditions radio communication, positioning systems and other components are switched to low-power (e.g. sleep) or high-power (e.g. idle/busy) states. We apply dynamic power management, an optimization technique well-known from other domains, in order to compute energy-optimal power-management strategies, sometimes resulting in these strategies being stochastic. On the example of the traffic-light assistant, we present a MATLAB/Simulink-implemented framework for the generation, simulation and formal analysis of optimized power-management strategies, which is based on this technique. We study capabilities and limitations of this approach and sketch further applications in the automotive domain. (orig.)

  20. Optimal generator bidding strategies for power and ancillary services

    Science.gov (United States)

    Morinec, Allen G.

    As the electric power industry transitions to a deregulated market, power transactions are made upon price rather than cost. Generator companies are interested in maximizing their profits rather than overall system efficiency. A method to equitably compensate generation providers for real power, and ancillary services such as reactive power and spinning reserve, will ensure a competitive market with an adequate number of suppliers. Optimizing the generation product mix during bidding is necessary to maximize a generator company's profits. The objective of this research work is to determine and formulate appropriate optimal bidding strategies for a generation company in both the energy and ancillary services markets. These strategies should incorporate the capability curves of their generators as constraints to define the optimal product mix and price offered in the day-ahead and real time spot markets. In order to achieve such a goal, a two-player model was composed to simulate market auctions for power generation. A dynamic game methodology was developed to identify Nash Equilibria and Mixed-Strategy Nash Equilibria solutions as optimal generation bidding strategies for two-player non-cooperative variable-sum matrix games with incomplete information. These games integrated the generation product mix of real power, reactive power, and spinning reserve with the generators's capability curves as constraints. The research includes simulations of market auctions, where strategies were tested for generators with different unit constraints, costs, types of competitors, strategies, and demand levels. Studies on the capability of large hydrogen cooled synchronous generators were utilized to derive useful equations that define the exact shape of the capability curve from the intersections of the arcs defined by the centers and radial vectors of the rotor, stator, and steady-state stability limits. The available reactive reserve and spinning reserve were calculated given a

  1. Brand Strategy and Japan’s Soft Power

    Institute of Scientific and Technical Information of China (English)

    Xing; YAN

    2015-01-01

    The 21st century is the time of brand strategy showing its position and importance in operation of enterprises.Rapid rise of the brand strategy in operation and management of enterprises has profound social and operation background.The development process of brand strategy also reflects evolution of market economy.A country’s cultural influence power depends on its brand equity.An essential task of brand promotion for a county is to narrow the gap between original image and target image,change the past or one-sided image of the public to products of the country,and implement effective communication and propaganda with the aid of related resource system in the country’s soft power,and accept new excellent image.Fundamentally,lifting national soft power is to set up distinct and charming national brand or national image.The influence power with culture and communication as core is the direct manifestation of a country’s core competitiveness.Brand is an outstanding feature of a country’s strength.Brand stretching can promote liftoff of national economy.In expanding international market,famous brands will play a more and more important role.

  2. Optimal energy management strategy for battery powered electric vehicles

    International Nuclear Information System (INIS)

    Xi, Jiaqi; Li, Mian; Xu, Min

    2014-01-01

    Highlights: • The power usage for battery-powered electrical vehicles with in-wheel motors is maximized. • The battery and motor dynamics are examined emphasized on the power conversion and utilization. • The optimal control strategy is derived and verified by simulations. • An analytic expression of the optimal operating point is obtained. - Abstract: Due to limited energy density of batteries, energy management has always played a critical role in improving the overall energy efficiency of electric vehicles. In this paper, a key issue within the energy management problem will be carefully tackled, i.e., maximizing the power usage of batteries for battery-powered electrical vehicles with in-wheel motors. To this end, the battery and motor dynamics will be thoroughly examined with particular emphasis on the power conversion and power utilization. The optimal control strategy will then be derived based on the analysis. One significant contribution of this work is that an analytic expression for the optimal operating point in terms of the component and environment parameters can be obtained. Owing to this finding, the derived control strategy is also rendered a simple structure for real-time implementation. Simulation results demonstrate that the proposed strategy works both adaptively and robustly under different driving scenarios

  3. Dyadic Power Profiles: Power-Contingent Strategies for Value Creation in Negotiation

    Science.gov (United States)

    Olekalns, Mara; Smith, Philip Leigh

    2013-01-01

    Using a simulated employment negotiation, we tested the conditional relationships among dyadic power profiles (symmetric high, symmetric low, and asymmetric), the choice and sequencing of strategies, and value creation. We showed that negotiators in symmetric high, symmetric low, and asymmetric power dyads took distinctly different paths to value…

  4. Power Generation Strategy Development in Croatia

    International Nuclear Information System (INIS)

    Curkovic, A.; Androcec, I.; Tarnik, T.

    2010-01-01

    Electricity generation as an economic sector contributes to the national GDP through increasing investments and exports. In the period from 2000 to 2008 the annual growth rate of final electricity demand was 3,8% which was higher than for any other energy form. Almost 1200 MW of thermal power plants will go out of system due to lifetime (more than 30 years). Energy Strategy is a basic document of the Energy Act with the purpose to define energy policy and future plans for energy development of the Republic of Croatia till 2020. Based on the adopted strategy the Government will create the Energy Strategy Implementation Programme for the four-year period. Croatian's energy development should be based on best available technologies as well as on energy-related, economic and environmental assessment of all available energy options. Energy strategy of Croatia (NN 130/09) puts up next goals: 300 MW hydro power plants (bigger than 10 MW), 1200 MW gas-fired thermal power plants (including 300 MW of cogeneration), 1200 MW of coal-fired thermal power plants, and 35% of renewable (including hydro). The market, i.e. a competitive generation, is the driving force in the construction of new power plants. The main stimulus for the construction is the possibility of definite return of invested capital as well as earning of reasonable profit for investors. Choose of location, environmental impact and competitiveness are main criteria for decision making. Technological and financial terms of new power plant is under influence of the law of supply and demand, so short marginal costs are in the first view - power plant life is at least 30 years - how to deal with this conditions, who will invest in long-term projects with condition of short pay-back period. Climate change and greenhouse gas emissions have become a priority development issue. The main challenge is a long-term development of economy with decreased emission of carbon dioxide. Kyoto protocol obligations, Copenhagen Accord

  5. 76 FR 31957 - Buckeye Power, Inc.; Notice of Filing

    Science.gov (United States)

    2011-06-02

    ... to supply of Reactive Power and Voltage Control from Generation Sources Services, as provided by... Washington, DC. There is an ``eSubscription'' link on the Web site that enables subscribers to receive e-mail...

  6. Strategies for growth of hydro electric power

    International Nuclear Information System (INIS)

    Khera, D.V.

    1998-01-01

    Hydro power on account of its several inherent advantages has a key role to play in the development of long term energy strategies based on diversified and balance use of natural national resources. Our country is fortunate to be endowed with large hydro-electric potential. It is estimated that the hydro potential while fully developed may yield to an installed capacity of 1,50,000 MW. An attempt has been made in this paper to examine and analyse the status and trend of hydro power development, need for accelerated development of hydro power, myths about hydro electric projects, principal causes responsible for scaling down of hydro share in the total installed capacity and strategies which could restore optimum hydro thermal mix. (author)

  7. 77 FR 61595 - Northern Illinois Municipal Power; Notice of Filing

    Science.gov (United States)

    2012-10-10

    ... Illinois Municipal Power filed its Revised and Superseding Proposed Revenue Requirement for reactive supply... Reference Room in Washington, DC. There is an ``eSubscription'' link on the web site that enables...

  8. Information is Power, Using Information is Powerful: Components of a National Information Strategy

    National Research Council Canada - National Science Library

    Parks, Wayne

    2004-01-01

    .... The current National Security Strategy addresses diplomatic, economic, and military power, but does not provide any substantial effort to instill an information campaign into the overall national strategy...

  9. Delta Power Control Strategy for Multistring Grid-Connected PV Inverters

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

    2017-01-01

    , is required for grid support (e.g., during frequency deviation). In this paper, a cost-effective solution to realize delta power control (DPC) for grid-connected PV systems is presented, where the multistring PV inverter configuration is adopted. This control strategy is a combination of maximum power point...... tracking (MPPT) and constant power generation (CPG) modes. In this control scheme, one PV string operating in the MPPT mode estimates the available power, whereas the other PV strings regulate the total PV power by the CPG control strategy in such a way that the delta power constraint for the entire PV...... system is achieved. Simulations and experiments have been performed on a 3-kW single-phase grid-connected PV system. The results have confirmed the effectiveness of the proposed DPC strategy, where the power reserve according to the delta power constraint is achieved under several operating conditions....

  10. 11 CFR 100.52 - Gift, subscription, loan, advance or deposit of money.

    Science.gov (United States)

    2010-01-01

    ... money. 100.52 Section 100.52 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS..., advance or deposit of money. (a) A gift, subscription, loan (except for a loan made in accordance with 11 CFR 100.72 and 100.73), advance, or deposit of money or anything of value made by any person for the...

  11. Energy management strategies for vehicle power nets

    NARCIS (Netherlands)

    Koot, M.W.T.; Jager, de A.G.; Kessels, J.T.B.A.; Heemels, W.P.M.H.; Bosch, van den P.P.J.

    2004-01-01

    In the near future a significant increase in electric power consumption in vehicles is to be expected. To limit the associated increase in fuel consumption and exhaust emissions, smart strategies for the generation, storage/retrieval, distribution, and consumption of the electric power can be used.

  12. 76 FR 26282 - Buckeye Power, Inc.; Notice of Filing

    Science.gov (United States)

    2011-05-06

    ... requirement for its contribution to the supply of Reactive Power and Voltage Control from Generation Sources... Washington, DC. There is an ``eSubscription'' link on the Web site that enables subscribers to receive e-mail...

  13. Role of library's subscription licenses in promoting open access to scientific research

    KAUST Repository

    Buck, Stephen

    2018-01-01

    This presentation, based on KAUST’’s experience to date, will attempt to explain the different ways of bringing Open Access models to scientific Publisher’s licenses. Our dual approach with offset pricing is to redirect subscription money to publishing money and embed green open access deposition terms in understandable language in our license agreements. Resolving the inherent complexities in open access publishing, repository depositions and offsetting models will save libraries money and also time wasted on tedious and unnecessary administration work. Researchers will also save their time with overall clarity and transparency. This will enable trust and, where mistakes are made, and there inevitably will be with untried models, we can learn from these mistakes and make better, more robust services with auto deposition of our articles to our repository fed by Publishers’ themselves. The plan is to cover all Publishers with OA license terms for KAUST author’s right while continuing our subscription to them. There are marketing campaigns, awareness sessions are planned, in addition to establishing Libguides to help researchers, in addition to manage offset pricing models.

  14. Role of library's subscription licenses in promoting open access to scientific research

    KAUST Repository

    Buck, Stephen

    2018-04-30

    This presentation, based on KAUST’’s experience to date, will attempt to explain the different ways of bringing Open Access models to scientific Publisher’s licenses. Our dual approach with offset pricing is to redirect subscription money to publishing money and embed green open access deposition terms in understandable language in our license agreements. Resolving the inherent complexities in open access publishing, repository depositions and offsetting models will save libraries money and also time wasted on tedious and unnecessary administration work. Researchers will also save their time with overall clarity and transparency. This will enable trust and, where mistakes are made, and there inevitably will be with untried models, we can learn from these mistakes and make better, more robust services with auto deposition of our articles to our repository fed by Publishers’ themselves. The plan is to cover all Publishers with OA license terms for KAUST author’s right while continuing our subscription to them. There are marketing campaigns, awareness sessions are planned, in addition to establishing Libguides to help researchers, in addition to manage offset pricing models.

  15. Does SDDS Subscription Reduce Borrowing Costs for Emerging Market Economies?

    OpenAIRE

    John Cady

    2005-01-01

    Does macroeconomic data transparency-as signaled by subscription to the IMF's Special Data Dissemination Standard (SDDS)-help reduce borrowing costs in international capital markets? This question is examined using data on new issues of sovereign foreign-currency-denominated (U.S. dollar, yen, and euro) bonds for several emerging market economies. Panel econometric estimates indicate that spreads on new bond issues declined on average by close to 20 percent, or by an average of about 55 basis...

  16. Global power: Markets and strategies

    International Nuclear Information System (INIS)

    Poirer, J.L.

    1998-01-01

    The author will first present an updated view of the global power market activity, including opportunities in power generation, transmission and distribution. This will include a review of the trends in closings and transaction flowed by type of activity and geographic area. Estimates will be based on Hagler Bailly's comprehensive database on global power transactions and project announcements. The firm has also worked with dozens of global power companies since 1990. Second, the author will review trends in terms of regulatory changes, project cost trends, developers' project experiences, and financing issues. This systematic review will be the foundation for projection of future market activity (e.g., number of closing by type of project through 2000). A forecast of future greenfield and privatization activity will be provided and the key markets will be highlighted. Third, the author will present an updated view of the competition in the global power market (including the various types of competitors and changes in their respective market posture). Finally, the author will discuss the various types of strategies and business models that are followed by key global power players

  17. Active power control strategies for inverter-based distributed power generation adapted to grid-fault ride-through requirements

    NARCIS (Netherlands)

    Wang, F.; Duarte, J.L.; Hendrix, M.A.M.

    2009-01-01

    Distributed power generation is expected to deliver power into the grid without interruption during voltage dips. To improve system ride-through capabilities, a generalized active power control strategy is proposed for grid-interfacing inverters. Specifically, a current reference generation strategy

  18. Strategies for competitive nuclear power plants

    International Nuclear Information System (INIS)

    1999-11-01

    This technical publication on competitive strategies for nuclear power plants (NPPs) is part of an ongoing project on management of NPP operations in a competitive environment. The overall objective of this project is to assist the management of operating organizations and NPPs in identifying and implementing appropriate measures to remain competitive in a rapidly changing business environment. Other documents that have been written on this topic have focused on how the environment in which NPPs operate is changing. This report instead focuses on strategies and techniques that operating organization and NPP managers can use to succeed in this environment. Of particular note is ongoing OECD/NEA work to describe the environment for nuclear power in competitive electricity markets. The main objective of the OECD/NEA study is to review the impacts of increasing market competition on the nuclear power sectors in OECD Member countries. The OECD/NEA study is identifying various nuclear aspects which have to be considered in relation to the regulatory reform of the electricity sector in OECD Member States. The OECD/NEA work was co-ordinated with the development of this IAEA report; staff members from the two organizations participated in the development and review of the associated documents. Thus, the strategies and techniques identified in this report are consistent with the impacts of increasing market competition identified in the OECD/NEA study

  19. Priority Control Strategy of VSC-MTDC System for Integrating Wind Power

    Directory of Open Access Journals (Sweden)

    Wen-ning Yan

    2015-01-01

    Full Text Available For the obvious advantages in integrating wind power, multiterminal HVDC transmission system (VSC-MTDC is widely used. The priority control strategy is proposed in this paper considering the penetration rate of wind power for the AC grid. The strategy aims to solve the problems of power allocation and DC voltage control of the DC system. The main advantage of this strategy is that the demands for wind power of different areas can be satisfied and a power reference for the wind power trade can also be provided when wind farms transmit active power to several AC grids through the DC network. The objective is that power is well distributed according to the output power of wind farm with the demand of AC system and satisfactory control performance of DC voltage is obtained.

  20. Flexible fault ride through strategy for wind farm clusters in power systems with high wind power penetration

    International Nuclear Information System (INIS)

    Wang, Songyan; Chen, Ning; Yu, Daren; Foley, Aoife; Zhu, Lingzhi; Li, Kang; Yu, Jilai

    2015-01-01

    Highlights: • A flexible fault ride through strategy is proposed. • The strategy comprises of grid code requirements and power restrictions. • Slight faults and moderate faults are the main defending objectives. • Temporary overloading capability of the doubly fed induction generator is considered. - Abstract: This paper investigates a flexible fault ride through strategy for power systems in China with high wind power penetration. The strategy comprises of adaptive fault ride through requirements and maximum power restrictions of the wind farms with weak fault ride through capabilities. The slight faults and moderate faults with high probability are the main defending objective of the strategy. The adaptive fault ride through requirement in the strategy consists of two sub fault ride through requirements, a temporary slight voltage ride through requirement corresponding to a slight fault incident, with a moderate voltage ride through requirement corresponding to a moderate fault. The temporary overloading capability of the wind farm is reflected in both requirements to enhance the capability to defend slight faults and to avoid tripping when the crowbar is disconnected after moderate faults are cleared. For those wind farms that cannot meet the adaptive fault ride through requirement, restrictions are put on the maximum power output. Simulation results show that the flexible fault ride through strategy increases the fault ride through capability of the wind farm clusters and reduces the wind power curtailment during faults

  1. 77 FR 47061 - Northern Illinois Municipal Power Agency; Notice of Filing

    Science.gov (United States)

    2012-08-07

    ... Municipal Power Agency filed a Proposed Revenue Requirement for reactive supply service under Midwest... Reference Room in Washington, DC. There is an ``eSubscription'' link on the web site that enables...

  2. Nuclear power plant outage optimisation strategy

    International Nuclear Information System (INIS)

    2002-10-01

    Competitive environment for electricity generation has significant implications for nuclear power plant operations, including among others the need of efficient use of resources, effective management of plant activities such as on-line maintenance and outages. Nuclear power plant outage management is a key factor for good, safe and economic nuclear power plant performance which involves many aspects: plant policy, co-ordination of available resources, nuclear safety, regulatory and technical requirements and, all activities and work hazards, before and during the outage. This technical publication aims to communicate these practices in a way they can be used by operators and utilities in the Member States of the IAEA. It intends to give guidance to outage managers, operating staff and to the local industry on planning aspects, as well as examples and strategies experienced from current plants in operation on the optimization of outage period. This report discusses the plant outage strategy and how this strategy is actually implemented. The main areas identified as most important for outage optimization by the utilities and government organizations participating in this report are: organization and management; outage planning and preparation, outage execution, safety outage review, and counter measures to avoid extension of outages and to easier the work in forced outages. This report was based on discussions and findings by the authors of the annexes and the participants of an Advisory Group Meeting on Determinant Causes for Reducing Outage Duration held in June 1999 in Vienna. The report presents the consensus of these experts regarding best common or individual good practices that can be used at nuclear power plants with the aim to optimize

  3. Novel deadbeat power control strategy for grid connected systems

    Directory of Open Access Journals (Sweden)

    Yousry Atia

    2015-09-01

    Full Text Available This paper introduces a novel approach for power control of three phase voltage source inverter (VSI in grid connected distribution generation system. In this approach, the control of active and reactive power is based on deadbeat control strategy. First, the difference between the reference and actual currents are introduced in different approach. Then current to power substitutions are carried out to obtain direct relationship between the required inverter voltage and instantaneous power errors. There is no need for coordinate transformation or PLL, where the required inverter voltage vector calculations carried out in α–β stationary reference frame. The proposed technique introduces two cross coupling components in the control function. Including these two components, the controller can achieve nearly zero steady-state tracking error of the controlled variables. To obtain fixed switching frequency operations, space vector modulation (SVM is used to synthesize the required inverter voltage vector and to generate the switching pulses for the VSI. The proposed strategy has the simplicity of the direct power control (DPC technique and doesn’t require any current control loops. The proposed strategy is experimentally implemented using fixed-point microcontroller. Simulation and experimental results are presented to confirm the superiority of the proposed strategy.

  4. Nuclear Power Plant Outage Optimization Strategy. 2016 Edition

    International Nuclear Information System (INIS)

    2016-10-01

    This publication is an update of IAEA-TECDOC-1315, Nuclear Power Plant Outage Optimisation Strategy, which was published in 2002, and aims to communicate good outage management practices in a manner that can be used by operators and utilities in Member States. Nuclear power plant outage management is a key factor for safe and economic nuclear power plant performance. This publication discusses plant outage strategy and how this strategy is actually implemented. The main areas that are important for outage optimization that were identified by the utilities and government organizations participating in this report are: 1) organization and management; 2) outage planning and preparation; 3) outage execution; 4) safety outage review; and 5) counter measures to avoid the extension of outages and to facilitate the work in forced outages. Good outage management practices cover many different areas of work and this publication aims to communicate these good practices in a way that they can be used effectively by operators and utilities

  5. Simplified reactive power management strategy for complex power grids under stochastic operation and incomplete information

    DEFF Research Database (Denmark)

    Vlachogiannis, Ioannis (John)

    2009-01-01

    grids is a major issue for system operators. Under these circumstances an online reactive power management strategy with minimum risk concerning all uncertain and stochastic parameters is proposed. Therefore, new concepts such as reactive power-weighted node-to-node linking and reactive power control......In the current released energy market, the large-scale complex transmission networks and the distribution ones with dispersed energy sources and "intelligent" components operate under uncertainties, stochastic and prior incomplete information. A safe and reliable operation of such complex power...... capability are introduced. A distributed and interconnected stochastic learning automata system is implemented to manage, in a unified and unique way, the reactive power in complex power grids with stochastic reactive power demand and detect the vulnerable part. The proposed simplified strategy can also...

  6. The L-Type Voltage-Gated Calcium Channel Ca [subscript V] 1.2 Mediates Fear Extinction and Modulates Synaptic Tone in the Lateral Amygdala

    Science.gov (United States)

    Temme, Stephanie J.; Murphy, Geoffrey G.

    2017-01-01

    L-type voltage-gated calcium channels (LVGCCs) have been implicated in both the formation and the reduction of fear through Pavlovian fear conditioning and extinction. Despite the implication of LVGCCs in fear learning and extinction, studies of the individual LVGCC subtypes, Ca[subscript V]1.2 and Ca[subscript V] 1.3, using transgenic mice have…

  7. Strategy of nuclear power in Korea, non-nuclear-weapon state and peaceful use of nuclear power

    International Nuclear Information System (INIS)

    Nagasaki, Takao

    2005-01-01

    The nuclear power plant started at Kori in Korea in April, 1978. Korea has carried out development of nuclear power as a national policy. The present capacity of nuclear power plants takes the sixes place in the world. It supplies 42% total power generation. The present state of nuclear power plant, nuclear fuel cycle facility, strategy of domestic production of nuclear power generation, development of next generation reactor and SMART, strategy of export in corporation with industry, government and research organization, export of nuclear power generation in Japan, nuclear power improvement project with Japan, Korea and Asia, development of nuclear power system with nuclear diffusion resistance, Hybrid Power Extraction Reactor System, radioactive waste management and construction of joint management and treatment system of spent fuel in Asia are stated. (S.Y.)

  8. Operational Experience of an Open-Access, Subscription-Based Mass Spectrometry and Proteomics Facility

    Science.gov (United States)

    Williamson, Nicholas A.

    2018-03-01

    This paper discusses the successful adoption of a subscription-based, open-access model of service delivery for a mass spectrometry and proteomics facility. In 2009, the Mass Spectrometry and Proteomics Facility at the University of Melbourne (Australia) moved away from the standard fee for service model of service provision. Instead, the facility adopted a subscription- or membership-based, open-access model of service delivery. For a low fixed yearly cost, users could directly operate the instrumentation but, more importantly, there were no limits on usage other than the necessity to share available instrument time with all other users. All necessary training from platform staff and many of the base reagents were also provided as part of the membership cost. These changes proved to be very successful in terms of financial outcomes for the facility, instrument access and usage, and overall research output. This article describes the systems put in place as well as the overall successes and challenges associated with the operation of a mass spectrometry/proteomics core in this manner. [Figure not available: see fulltext.

  9. PAQ Types and Power Strategies Used in Intimate Relationships.

    Science.gov (United States)

    Falbo, Toni

    1982-01-01

    Examined kinds of power strategies used by masculine, feminine, androgynous, and undifferentiated people in their intimate relationships. Androgynous people reported using primarily bilateral strategies, such as persuasion. Undifferentiated people reported using primarily unilateral strategies, such as doing what they wanted, regardless of their…

  10. Wind Farm Active Power Dispatch for Output Power Maximizing Based on a Wind Turbine Control Strategy for Load Minimizing

    DEFF Research Database (Denmark)

    Zhang, Baohua; Hu, Weihao; Hou, Peng

    2015-01-01

    Inclusion of the wake effect in the wind farm control design (WF) can increase the total captured power by wind turbines (WTs), which is usually implemented by derating upwind WTs. However, derating the WT without a proper control strategy will increase the structural loads, caused by operation...... in stall mode. Therefore, the WT control strategy for derating operation should be considered in the attempt at maximizing the total captured power while reducing structural loads. Moreover, electrical power loss on the transmission system inside a WF is also not negligible for maximizing the total output...... power of the WF. In this paper, an optimal active power dispatch strategy based on a WT derating strategy and considering the transmission loss is proposed for maximizing the total output power. The active power reference of each WT is chosen as the optimization variable. A partial swarm optimizing...

  11. Energy managment strategies for vehicular electric power systems

    NARCIS (Netherlands)

    Koot, M.W.T.; Kessels, J.T.B.A.; Jager, de A.G.; Heemels, W.P.M.H.; Bosch, van den P.P.J.; Steinbuch, M.

    2005-01-01

    In the near future, a significant increase in electric power consumption in vehicles is expected. To limit the associated increase in fuel consumption and exhaust emissions, smart strategies for the generation, storage/retrieval, distribution, and consumption of electric power will be used. Inspired

  12. 31 CFR 344.8 - What other provisions apply to subscriptions for Demand Deposit securities?

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false What other provisions apply to subscriptions for Demand Deposit securities? 344.8 Section 344.8 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY BUREAU OF THE PUBLIC...

  13. Feedback power control strategies in wireless sensor networks with joint channel decoding.

    Science.gov (United States)

    Abrardo, Andrea; Ferrari, Gianluigi; Martalò, Marco; Perna, Fabio

    2009-01-01

    In this paper, we derive feedback power control strategies for block-faded multiple access schemes with correlated sources and joint channel decoding (JCD). In particular, upon the derivation of the feasible signal-to-noise ratio (SNR) region for the considered multiple access schemes, i.e., the multidimensional SNR region where error-free communications are, in principle, possible, two feedback power control strategies are proposed: (i) a classical feedback power control strategy, which aims at equalizing all link SNRs at the access point (AP), and (ii) an innovative optimized feedback power control strategy, which tries to make the network operational point fall in the feasible SNR region at the lowest overall transmit energy consumption. These strategies will be referred to as "balanced SNR" and "unbalanced SNR," respectively. While they require, in principle, an unlimited power control range at the sources, we also propose practical versions with a limited power control range. We preliminary consider a scenario with orthogonal links and ideal feedback. Then, we analyze the robustness of the proposed power control strategies to possible non-idealities, in terms of residual multiple access interference and noisy feedback channels. Finally, we successfully apply the proposed feedback power control strategies to a limiting case of the class of considered multiple access schemes, namely a central estimating officer (CEO) scenario, where the sensors observe noisy versions of a common binary information sequence and the AP's goal is to estimate this sequence by properly fusing the soft-output information output by the JCD algorithm.

  14. Feedback Power Control Strategies inWireless Sensor Networks with Joint Channel Decoding

    Directory of Open Access Journals (Sweden)

    Fabio Perna

    2009-11-01

    Full Text Available In this paper, we derive feedback power control strategies for block-faded multiple access schemes with correlated sources and joint channel decoding (JCD. In particular, upon the derivation of the feasible signal-to-noise ratio (SNR region for the considered multiple access schemes, i.e., the multidimensional SNR region where error-free communications are, in principle, possible, two feedback power control strategies are proposed: (i a classical feedback power control strategy, which aims at equalizing all link SNRs at the access point (AP, and (ii an innovative optimized feedback power control strategy, which tries to make the network operational point fall in the feasible SNR region at the lowest overall transmit energy consumption. These strategies will be referred to as “balanced SNR” and “unbalanced SNR,” respectively. While they require, in principle, an unlimited power control range at the sources, we also propose practical versions with a limited power control range. We preliminary consider a scenario with orthogonal links and ideal feedback. Then, we analyze the robustness of the proposed power control strategies to possible non-idealities, in terms of residual multiple access interference and noisy feedback channels. Finally, we successfully apply the proposed feedback power control strategies to a limiting case of the class of considered multiple access schemes, namely a central estimating officer (CEO scenario, where the sensors observe noisy versions of a common binary information sequence and the AP’s goal is to estimate this sequence by properly fusing the soft-output information output by the JCD algorithm.

  15. Battery Peak Power Shaving Strategy to Prolong Battery Life for Electric Buses

    NARCIS (Netherlands)

    Pham, T.H.; Rosea, B.; Wilkins, S.

    2016-01-01

    This paper presents a battery peak power shaving strategy for battery electric buses. The developed strategy restricts the battery charge/discharge power when the propulsion power demand is high to avoid high deterioration of the battery capacity during operation. Without reducing the propulsion

  16. Control Strategy of Active Power Filter Based on Modular Multilevel Converter

    Science.gov (United States)

    Xie, Xifeng

    2018-03-01

    To improve the capacity, pressure resistance and the equivalent switching frequency of active power filter (APF), a control strategy of APF based on Modular Multilevel Converter (MMC) is presented. In this Control Strategy, the indirect current control method is used to achieve active current and reactive current decoupling control; Voltage Balance Control Strategy is to stabilize sub-module capacitor voltage, the predictive current control method is used to Track and control of harmonic currents. As a result, the harmonic current is restrained, and power quality is improved. Finally, the simulation model of active power filter controller based on MMC is established in Matlab/Simulink, the simulation proves that the proposed strategy is feasible and correct.

  17. Rethinking the Subscription Paradigm for Journals: Using Interlibrary Loan in Collection Development for Serials

    Science.gov (United States)

    Barton, Gail Perkins; Relyea, George E.; Knowlton, Steven A.

    2018-01-01

    Many librarians evaluate local Interlibrary Loan (ILL) statistics as part of collection development decisions concerning new subscriptions. In this study, the authors examine whether the number of ILL article requests received in one academic year can predict the use of those same journal titles once they are added as library resources. There is…

  18. Non-Exercise Estimation of VO[subscript 2]max Using the International Physical Activity Questionnaire

    Science.gov (United States)

    Schembre, Susan M.; Riebe, Deborah A.

    2011-01-01

    Non-exercise equations developed from self-reported physical activity can estimate maximal oxygen uptake (VO[subscript 2]max) as well as sub-maximal exercise testing. The International Physical Activity Questionnaire is the most widely used and validated self-report measure of physical activity. This study aimed to develop and test a VO[subscript…

  19. A control strategy for multi-functional converter to improve grid power quality

    DEFF Research Database (Denmark)

    Li, Fei; Wang, Xiongfei; Chen, Zhe

    2011-01-01

    The extensive use of converter-interfacing distributed energy resources (DER), combined with a large amount of nonlinear and unbalanced loads connected to the distribution power system, has led to power quality problem. This paper proposes a control strategy for a three-phase four-leg multi-funct......) for multi-functional converter is described. Simulation and hardware in the loop real time test results carried on a three-phase four-wire distributed generation system illustrate the effectiveness of the proposed control strategy.......The extensive use of converter-interfacing distributed energy resources (DER), combined with a large amount of nonlinear and unbalanced loads connected to the distribution power system, has led to power quality problem. This paper proposes a control strategy for a three-phase four-leg multi......-functional converter which can compensate reactive power, harmonic currents, unbalance, and neutral current simultaneously under distorted voltage conditions, besides the active power exchange. The capacity of the converter is taken into account. The proposed control strategy based on synchronous reference frame (SRF...

  20. Evaluation of Electric Power Procurement Strategies by Stochastic Dynamic Programming

    Science.gov (United States)

    Saisho, Yuichi; Hayashi, Taketo; Fujii, Yasumasa; Yamaji, Kenji

    In deregulated electricity markets, the role of a distribution company is to purchase electricity from the wholesale electricity market at randomly fluctuating prices and to provide it to its customers at a given fixed price. Therefore the company has to take risk stemming from the uncertainties of electricity prices and/or demand fluctuation instead of the customers. The way to avoid the risk is to make a bilateral contact with generating companies or install its own power generation facility. This entails the necessity to develop a certain method to make an optimal strategy for electric power procurement. In such a circumstance, this research has the purpose for proposing a mathematical method based on stochastic dynamic programming and additionally considering the characteristics of the start-up cost of electric power generation facility to evaluate strategies of combination of the bilateral contract and power auto-generation with its own facility for procuring electric power in deregulated electricity market. In the beginning we proposed two approaches to solve the stochastic dynamic programming, and they are a Monte Carlo simulation method and a finite difference method to derive the solution of a partial differential equation of the total procurement cost of electric power. Finally we discussed the influences of the price uncertainty on optimal strategies of power procurement.

  1. Performance evaluation of control strategies for power maneuvering event of the KALIMER-600

    International Nuclear Information System (INIS)

    Seong, Seong-Hwan; Kim, Seong-O

    2012-01-01

    Highlights: ► The performance of three power control strategies of the KALIMER-600 was evaluated. ► There are turbine-, reactor- and feedwater-leading strategies in this study. ► For this, a performance analysis code was developed in this study. ► Simulation results show the turbine-leading is the best alternative. ► The feedwater-leading seems to be the second option. - Abstract: A sodium-cooled fast reactor named KALIMER-600 has been under development at KAERI. It is a pool-type reactor with the intermediate loops filled with sodium and has a superheated steam cycle with the once-through steam generators. Since the characteristic of the power control of the KALIMER-600 is expected to be different with that of a conventional power plant, the performance of the turbine-leading, reactor-leading and feedwater-leading control strategies for a power maneuvering event of the KALIMER-600 was evaluated in this study. The turbine-leading and reactor-leading strategies are very similar to those of a conventional water reactor but the feedwater-leading strategy is very similar to that of a fossil plant. Also, a performance analysis code which can analyze the plant dynamics of the KALIMER-600 and simulate the control actions during a power maneuvering event was developed. To evaluate the performance of control strategies, a simple power maneuvering event including a 10% step change and a ramp change with a rate of 5%/min was assumed and simulated. Through the simulation results, the turbine-leading strategy is proven to be very suitable for the KALIMER-600 and the feedwater-leading strategy for power maneuvering seems to be a good alternative for the power control. In further studies, various performance-related events such as the reactor power cutback, turbine runback and some transients will be evaluated and the best control strategy will be suggested.

  2. Minimal average consumption downlink base station power control strategy

    OpenAIRE

    Holtkamp H.; Auer G.; Haas H.

    2011-01-01

    We consider single cell multi-user OFDMA downlink resource allocation on a flat-fading channel such that average supply power is minimized while fulfilling a set of target rates. Available degrees of freedom are transmission power and duration. This paper extends our previous work on power optimal resource allocation in the mobile downlink by detailing the optimal power control strategy investigation and extracting fundamental characteristics of power optimal operation in cellular downlink. W...

  3. Magazine "Companion Websites" and the Demand for Newsstand Sales and Subscriptions

    DEFF Research Database (Denmark)

    Kaiser, Ulrich; Kongsted, H.C.

    2012-01-01

    analysis finds some support for the widespread belief that the Internet cannibalizes print media. On average, a 1% increase in companion website traffic is associated with a weakly significant decrease in total print circulation by 0.15%. This association is mainly driven by a statistically significant...... and negative mapping between website visits and kiosk sales, although they do not find any statistically significant relationship between website visits and subscriptions. The latter finding is reassuring for publishers because advertisers value a large subscriber base. Moreover, the authors show...

  4. Peer review quality and transparency of the peer-review process in open access and subscription journals

    NARCIS (Netherlands)

    Wicherts, J.M.

    2016-01-01

    Background Recent controversies highlighting substandard peer review in Open Access (OA) and traditional (subscription) journals have increased the need for authors, funders, publishers, and institutions to assure quality of peer-review in academic journals. I propose that transparency of the

  5. Bidding strategy in pay-as-bid power markets

    International Nuclear Information System (INIS)

    Oloomi-Buygi, M.; Nazarian, H.

    2007-01-01

    Electricity markets around the world can be classified as pool-based electricity markets; pure bilateral contract markets; and hybrid markets. The bidding strategy has emerged as an important issue for producers in pool-based electricity markets. Power producers can use several approaches to develop bidding strategies that determine the optimal bid to maximize profit. The various approaches fall into 2 categories, notably forecasting market clearing prices, and estimating the behaviour of other competitors. This paper presented a simple and efficient approach for developing a bidding strategy in pay-as-bid electricity markets. It used the multiple step bid to estimate the optimal bid. One step was allocated to revenue earning while the other steps were allocated to information acquiring. Information acquiring steps obtain information from the market for estimating the optimal bid of the next day. The proposed method was used at a specified power generating unit operating in the Iranian electricity market. The study showed that the proposed bidding strategy can increase the total revenue of the unit by thirty nine per cent. 22 refs., 8 figs

  6. Space nuclear power: a strategy for tomorrow

    International Nuclear Information System (INIS)

    Buden, D.; Angelo, J. Jr.

    1981-01-01

    Energy: reliable, portable, abundant and low cost will be a most critical factor, perhaps the sine qua non, for the unfolding of man's permanent presence in space. Space-based nuclear power, in turn, is a key technology for developing such space platforms and the transportation systems necessary to service them. A strategy for meeting space power requirements is the development of a 100-kW(e) nuclear reactor system for high earth orbit missions, transportation from Shuttle orbits to geosynchronous orbit, and for outer planet exploration. The component technology for this nuclear power plant is now underway at the Los Alamos National Laboratory. As permanent settlements are established on the Moon and in space, multimegawatt power plants will be needed. This would involve different technology similar to terrestrial nuclear power plants

  7. Optimal Offering Strategies for Wind Power in Energy and Primary Reserve Markets

    DEFF Research Database (Denmark)

    Soares, Tiago; Pinson, Pierre; Jensen, Tue Vissing

    2016-01-01

    generation from the turbines. These offering strategies aim at maximizing expected revenues from both market floors using probabilistic forecasts for wind power generation, complemented with estimated regulation costs and penalties for failing to provide primary reserve. A set of numerical examples, as well......Wind power generation is to play an important role in supplying electric power demand, and will certainly impact the design of future energy and reserve markets. Operators of wind power plants will consequently develop adequate offering strategies, accounting for the market rules...... and the operational capabilities of the turbines, e.g., to participate in primary reserve markets. We consider two different offering strategies for joint participation of wind power in energy and primary reserve markets, based on the idea of proportional and constant splitting of potentially available power...

  8. Health sciences libraries' subscriptions to journals: expectations of general practice departments and collection-based analysis.

    Science.gov (United States)

    Barreau, David; Bouton, Céline; Renard, Vincent; Fournier, Jean-Pascal

    2018-04-01

    The aims of this study were to (i) assess the expectations of general practice departments regarding health sciences libraries' subscriptions to journals and (ii) describe the current general practice journal collections of health sciences libraries. A cross-sectional survey was distributed electronically to the thirty-five university general practice departments in France. General practice departments were asked to list ten journals to which they expected access via the subscriptions of their health sciences libraries. A ranked reference list of journals was then developed. Access to these journals was assessed through a survey sent to all health sciences libraries in France. Adequacy ratios (access/need) were calculated for each journal. All general practice departments completed the survey. The total reference list included 44 journals. This list was heterogeneous in terms of indexation/impact factor, language of publication, and scope (e.g., patient care, research, or medical education). Among the first 10 journals listed, La Revue Prescrire (96.6%), La Revue du Praticien-Médecine Générale (90.9%), the British Medical Journal (85.0%), Pédagogie Médicale (70.0%), Exercer (69.7%), and the Cochrane Database of Systematic Reviews (62.5%) had the highest adequacy ratios, whereas Family Practice (4.2%), the British Journal of General Practice (16.7%), Médecine (29.4%), and the European Journal of General Practice (33.3%) had the lowest adequacy ratios. General practice departments have heterogeneous expectations in terms of health sciences libraries' subscriptions to journals. It is important for librarians to understand the heterogeneity of these expectations, as well as local priorities, so that journal access meets users' needs.

  9. A Game Theoretical Approach Based Bidding Strategy Optimization for Power Producers in Power Markets with Renewable Electricity

    Directory of Open Access Journals (Sweden)

    Yi Tang

    2017-05-01

    Full Text Available In a competitive electricity market with substantial involvement of renewable electricity, maximizing profits by optimizing bidding strategies is crucial to different power producers including conventional power plants and renewable ones. This paper proposes a game-theoretic bidding optimization method based on bi-level programming, where power producers are at the upper level and utility companies are at the lower level. The competition among the multiple power producers is formulated as a non-cooperative game in which bidding curves are their strategies, while uniform clearing pricing is considered for utility companies represented by an independent system operator. Consequently, based on the formulated game model, the bidding strategies for power producers are optimized for the day-ahead market and the intraday market with considering the properties of renewable energy; and the clearing pricing for the utility companies, with respect to the power quantity from different power producers, is optimized simultaneously. Furthermore, a distributed algorithm is provided to search the solution of the generalized Nash equilibrium. Finally, simulation results were performed and discussed to verify the feasibility and effectiveness of the proposed non-cooperative game-based bi-level optimization approach.

  10. Cognitive strategies in the mental rotation task revealed by EEG spectral power.

    Science.gov (United States)

    Gardony, Aaron L; Eddy, Marianna D; Brunyé, Tad T; Taylor, Holly A

    2017-11-01

    The classic mental rotation task (MRT; Shepard & Metzler, 1971) is commonly thought to measure mental rotation, a cognitive process involving covert simulation of motor rotation. Yet much research suggests that the MRT recruits both motor simulation and other analytic cognitive strategies that depend on visuospatial representation and visual working memory (WM). In the present study, we investigated cognitive strategies in the MRT using time-frequency analysis of EEG and independent component analysis. We scrutinized sensorimotor mu (µ) power reduction, associated with motor simulation, parietal alpha (pα) power reduction, associated with visuospatial representation, and frontal midline theta (fmθ) power enhancement, associated with WM maintenance and manipulation. µ power increased concomitant with increasing task difficulty, suggesting reduced use of motor simulation, while pα decreased and fmθ power increased, suggesting heightened use of visuospatial representation processing and WM, respectively. These findings suggest that MRT performance involves flexibly trading off between cognitive strategies, namely a motor simulation-based mental rotation strategy and WM-intensive analytic strategies based on task difficulty. Flexible cognitive strategy use may be a domain-general cognitive principle that underlies aptitude and spatial intelligence in a variety of cognitive domains. We close with discussion of the present study's implications as well as future directions. Published by Elsevier Inc.

  11. Purchasing Power and Purchasing Strategies - Insights From the Humanitarian Sector

    OpenAIRE

    Pazirandeh, Ala

    2014-01-01

    In this dissertation, we discuss how buyers practice purchasing strategies in an asymmetric power situation favoring suppliers, and how their purchasing strategies practiced impact their purchasing power and buyer-supplier relationships. Organizations enter exchange relationships to access required resources not produced internally, and are exposed to uncertainty from not being able to fully control or predict flow of resources. Consequently they become dependent on their partners. Their leve...

  12. Comparison of Power Control Strategies for DFIG Wind Turbines

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Luna, A.; Rodríguez, P.

    2008-01-01

    The classical control techniques for regulating the active and reactive power delivery in doubly fed induction generators (DFIG), for wind power applications, are normally based on voltage oriented control (VOC) strategies. Among these algorithms, those that work in a synchronous reference frame...... VOC strategy able to control the operation of a DFIG in the αβ reference frame, with no need of flux position estimation, something that conducts to a more simple and robust algorithm. In order to evaluate the advantages of this new control proposal, namely VOC-RRF, their performance will be compared...

  13. Piracy versus Netflix : Subscription Video on Demand Dissatisfaction as an Antecedent of Piracy

    OpenAIRE

    Riekkinen, Janne

    2018-01-01

    Drawing from cognitive dissonance and neutralization theories, this study seeks to improve the understanding on consumer decision-making between the current legal and illegal video consumption alternatives. We develop and test a research model featuring Subscription Video on Demand (SVOD) satisfaction and various dimensions of SVOD quality as antecedents of video piracy neutralizations and attitudes. Based on results from an online survey among Finnish SVOD users, SVOD satisfaction is primari...

  14. Technical strategy map to employing nuclear power plant aging management

    International Nuclear Information System (INIS)

    Sekimura, Naoto; Kanno, Masanori

    2008-01-01

    Stated in this report are back ground of technical strategy map for nuclear power plant aging management, result of the first road map, significance of technical strategy map, introduction scenario, technology map, road map, upgrade in every year, three groups of academia, industry and government, plan of technical strategy map, upgrade system, comprehensive introduction scenario, measures of nuclear power plant aging management in Japan and the world, new inspection system, outline of 'technical strategy map 2008', preparation of technical information bases in industry, academia and government, collaboration of them, safety researches of neutron radiation damage, stress corrosion crack, fatigue, piping thinning, insulation degradation, concrete degradation, thermal aging, evaluation technologies of earthquake resistance, preparation of rules and standards, ideal maintenance, and training talent. (S.Y.)

  15. A low-power multi port register file design using a low-swing strategy

    International Nuclear Information System (INIS)

    Yan Hao; Liu Yan; Hua Siliang; Wang Donghui; Hou Chaohuan

    2012-01-01

    A low-power register file is designed by using a low-swing strategy and modified NAND address decoders. The proposed low-swing strategy is based on the feedback scheme and uses dynamic logic to reduce the active feedback power. This method contains two parts: WRITE and READ strategy. In the WRITE low-swing scheme, the modified memory cell is used to support low-swing WRITE. The modified NAND decoder not only dissipates less power, but also enables a great deal of area reduction. Compared with the conventional single-ended register file, the low-swing strategy saves 34.5% and 51.15% bit-line power in WRITE and READ separately. The post simulation results indicate a 39.4% power improvement when the twelve ports are all busy. (semiconductor integrated circuits)

  16. Sierra Leone : Power Sector Recovery Strategy, Phase I

    OpenAIRE

    World Bank

    2007-01-01

    Power Planning Associates has been appointed by the World Bank to prepare a strategy for the recovery of the National Power Authority (NPA). This Preliminary Report presents the findings of the audit and proposes potential counter measures to improve NPA s technical and financial performance. These counter measures are presented at the end of each section of the report and are summarised...

  17. Strategies of development of European power producers

    International Nuclear Information System (INIS)

    Heddebaut, D.

    2007-12-01

    This economical study answers the following questions: what is the dynamics of European power markets? What is the relative competitiveness of the different power production means? What are the determining factors of electricity wholesale prices? Who are the operators the most threatened by the rise of wholesale prices? To what extend power producers are impacted by the CO 2 constrain? Who are the most efficient producers? The analysis is based on 18 of the most representative groups of the European electric utilities. The first volume of the study presents the strategic perspectives of European power producers: dynamics and basic characteristics of European power markets, strategic options of European operators, typology and financial results of European power producers, scenarios of market reorganization according to Eurostaf (possible mega-mergers in the future, competition). Volume 2 makes a detailed analysis of the positioning and perspectives of the 18 selected groups: key figures, sourcing strategies, production means management, Eurostaf's diagnosis. (J.S.)

  18. Stochastic Optimal Wind Power Bidding Strategy in Short-Term Electricity Market

    DEFF Research Database (Denmark)

    Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte

    2012-01-01

    Due to the fluctuating nature and non-perfect forecast of the wind power, the wind power owners are penalized for the imbalance costs of the regulation, when they trade wind power in the short-term liberalized electricity market. Therefore, in this paper a formulation of an imbalance cost...... minimization problem for trading wind power in the short-term electricity market is described, to help the wind power owners optimize their bidding strategy. Stochastic optimization and a Monte Carlo method are adopted to find the optimal bidding strategy for trading wind power in the short-term electricity...... market in order to deal with the uncertainty of the regulation price, the activated regulation of the power system and the forecasted wind power generation. The Danish short-term electricity market and a wind farm in western Denmark are chosen as study cases due to the high wind power penetration here...

  19. Integral Representation of the Pictorial Proof of Sum of [superscript n][subscript k=1]k[superscript 2] = 1/6n(n+1)(2n+1)

    Science.gov (United States)

    Kobayashi, Yukio

    2011-01-01

    The pictorial proof of the sum of [superscript n][subscript k=1] k[superscript 2] = 1/6n(n+1)(2n+1) is represented in the form of an integral. The integral representations are also applicable to the sum of [superscript n][subscript k-1] k[superscript m] (m greater than or equal to 3). These representations reveal that the sum of [superscript…

  20. FORMULATION STRATEGY UNDER THE INFLUENCE OF POWER COMPETITION

    Directory of Open Access Journals (Sweden)

    Ljiljana Stošić Mihajlović

    2014-10-01

    Full Text Available In this work, the subject of the research is defined starting hypothesis that formulation in the form of answers to the question: What factors - competitive forces shape strategy? Strategy formulation essentially boils down to competition. Competitors are all - customers, suppliers, potential new entrants to the market and producers of substitutes - and depending on the industry, may be more or less important or active. The first primary determinant of a firm's profitability is the attractiveness of the system to which it belongs. Competitive strategy must be developed from the basic knowledge of the rules of competition that determine the attractiveness of an economic system. The ultimate aim of competitive strategy is to apply, or - ideally - a change these rules in favor of the company. In any economic system, regardless of Whether it is domestic or international, and Whether products or services, the rules of competition are embodied in five competitive factors, the five basic forces: the entry of new competitors into the market, the threat of substitution, bargaining power of the buyer, bargaining power of suppliers and rivalry among existing competitors. Joint strength of these forces determines the ultimate potential of an activity to make a profit.

  1. Knowledge preservation strategies for nuclear power plants

    International Nuclear Information System (INIS)

    Koruna, S.; Bachmann, H.

    2004-01-01

    The nuclear industry is currently facing several challenges. An internal threat to the safety and operations of nuclear power plants is the loss of those employees who hold knowledge that is either critical to operations or safety. This report discusses the possibilities to preserve knowledge in nuclear power plants. Dependent on the degree of tacitness two different knowledge preservation strategies can be discerned: personalization and codification. The knowledge preservation activities discussed are valued according to the criteria: cost, immediacy of availability and completeness

  2. Delta Power Control Strategy for Multi-String Grid-Connected PV Inverters

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

    2016-01-01

    With a still increasing penetration level of grid-connected PV systems, more advanced active power control functionalities have been introduced in certain grid regulations. A delta power constraint, where a portion of the active power from the PV panels is reserved during operation, is required...... for grid support (e.g., during frequency deviation). In this paper, a cost-effective solution to realize delta power control for grid-connected PV systems is presented, where the residential/commercial multi-string PV inverter configuration is adopted. This control strategy is a combination of Maximum...... for the entire PV system is achieved. Simulations and experiments have been performed on a 3-kW single-phase grid-connected PV system. The results have confirmed the effectiveness of the delta power control strategy, where the power reserve according to the delta power constraint is achieved under several...

  3. Reactive Power Injection Strategies for Single-Phase Photovoltaic Systems Considering Grid Requirements

    DEFF Research Database (Denmark)

    Yang, Yongheng; Wang, Huai; Blaabjerg, Frede

    2014-01-01

    .g. Germany and Italy. Those advanced features can be provided by next generation PV systems, and will be enhanced in the future to ensure an even efficient and reliable utilization of PV systems. In light of this, Reactive Power Injection (RPI) strategies for single-phase PV systems are explored...... in this paper. The RPI possibilities are: a) constant average active power control, b) constant active current control, c) constant peak current control and d) thermal optimized control strategy. All those strategies comply with the currently active grid codes, but are with different objectives. The proposed...... RPI strategies are demonstrated firstly by simulations and also tested experimentally on a 1 kW singe-phase grid-connected system in LVRT operation mode. Those results show the effectiveness and feasibilities of the proposed strategies with reactive power control during LVRT operation. The design...

  4. Dissonance and Neutralization of Subscription Streaming Era Digital Music Piracy : An Initial Exploration

    OpenAIRE

    Riekkinen, Janne

    2016-01-01

    Both legal and illegal forms of digital music consumption continue to evolve with wider adoption of subscription streaming services. With this paper, we aim to extend theory on digital music piracy by showing that the rising controversy and diminishing acceptance of illegal forms of consumption call for new theoretical components and interactions. We introduce a model that integrates insights from neutralization and cognitive dissonance theories. As an initial empirical test of th...

  5. A Free-Piston Linear Generator Control Strategy for Improving Output Power

    Directory of Open Access Journals (Sweden)

    Chi Zhang

    2018-01-01

    Full Text Available This paper presents a control strategy to improve the output power for a single-cylinder two-stroke free-piston linear generator (FPLG. The comprehensive simulation model of this FPLG is established and the operation principle is introduced. The factors that affect the output power are analyzed theoretically. The characteristics of the piston motion are studied. Considering the different features of the piston motion respectively in acceleration and deceleration phases, a ladder-like electromagnetic force control strategy is proposed. According to the status of the linear electric machine, the reference profile of the electromagnetic force is divided into four ladder-like stages during one motion cycle. The piston motions, especially the dead center errors, are controlled by regulating the profile of the electromagnetic force. The feasibility and advantage of the proposed control strategy are verified through comparison analyses with two conventional control strategies via MatLab/Simulink. The results state that the proposed control strategy can improve the output power by around 7–10% with the same fuel cycle mass.

  6. A new self-scheduling strategy for integrated operation of wind and pumped-storage power plants in power markets

    International Nuclear Information System (INIS)

    Varkani, Ali Karimi; Daraeepour, Ali; Monsef, Hassan

    2011-01-01

    Highlights: → A strategy for integrated operation of wind and pumped-storage plants is proposed. → Participation of both plants in energy and ancillary service markets is modeled. → The uncertainty of wind production is modeled by a novel probabilistic function. → The proposed strategy is tested on a real case in the Spanish electricity market. -- Abstract: Competitive structure of power markets causes various challenges for wind resources to participate in these markets. Indeed, production uncertainty is the main cause of their low income. Thus, they are usually supported by system operators, which is in contrast with the competitive paradigm of power markets. In this paper, a new strategy for increasing the profits of wind resources is proposed. In the suggested strategy, a Generation Company (GenCo), who owns both wind and pumped-storage plants, self-schedules the integrated operation of them regarding the uncertainty of wind power generation. For presenting an integrated self-schedule and obtaining a real added value of the strategy, participation of the GenCo in energy and ancillary service markets is modeled. The self-scheduling strategy is based on stochastic programming techniques. Outputs of the problem include generation offers in day-ahead energy market and ancillary service markets, including spinning and regulation reserve markets. A Neural Network (NN) based technique is used for modeling the uncertainty of wind power production. The proposed strategy is tested on a real wind farm in mainland, Spain. Moreover, added value of the strategy is presented in different conditions of the market.

  7. Nanosized TiO[subscript 2] for Photocatalytic Water Splitting Studied by Oxygen Sensor and Data Logger

    Science.gov (United States)

    Zhang, Ruinan; Liu, Song; Yuan, Hongyan; Xiao, Dan; Choi, Martin M. F.

    2012-01-01

    Photocatalytic water splitting by semiconductor photocatalysts has attracted considerable attention in the past few decades. In this experiment, nanosized titanium dioxide (nano-TiO[subscript 2]) particles are used to photocatalytically split water, which is then monitored by an oxygen sensor. Sacrificial reagents such as organics (EDTA) and metal…

  8. Forward Link Power Control Strategy and its Optimum Issue in CDMA Cellular Networks

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper, we propose a theoretical method in order to estimate the forward link outage probability and user capacity of a cellular system which are based on IS-95 CDMA standard, especialy impact of power control strategy and voice activity monitoring in the system under long-term fading effects, in which the light and heavy fadings are considered. According to the numerical results obtained in this paper, the power control strategy leads to approximately the threefold user capacity in contrast to the situation without power control strategy. The reults are compared with Interference-to-Signal Ratio (ISR) driven power control scheme[6][9] which can be used only for simulation of the system. The power control strategy not only improves the desired signal to the interference ratio in the reference user's receiver, but also offers uniform service to the user wherever it is located in the cell.

  9. Stand-alone excitation synchronous wind power generators with power flow management strategy

    Directory of Open Access Journals (Sweden)

    Tzuen-Lih Chern

    2014-09-01

    Full Text Available This study presents a stand-alone excitation synchronous wind power generator (SESWPG with power flow management strategy (PFMS. The rotor speed of the excitation synchronous generator tracks the utility grid frequency by using servo motor tracking technologies. The automatic voltage regulator governs the exciting current of generator to achieve the control goals of stable voltage. When wind power is less than the needs of the consumptive loading, the proposed PFMS increases motor torque to provide a positive power output for the loads, while keeping the generator speed constant. Conversely, during the periods of wind power greater than output loads, the redundant power of generator production is charged to the battery pack and the motor speed remains constant with very low power consumption. The advantage of the proposed SESWPG is that the generator can directly output stable alternating current (AC electricity without using additional DC–AC converters. The operation principles with software simulation for the system are described in detail. Experimental results of a laboratory prototype are shown to verify the feasibility of the system.

  10. Advanced power cycler with intelligent monitoring strategy of IGBT module under test

    DEFF Research Database (Denmark)

    Choi, U. M.; Blaabjerg, F.; Iannuzzo, F.

    2017-01-01

    and diode, which for the wear-out condition monitoring are presented. This advanced power cycler allows to perform power cycling test cost-effectively under conditions close to real power converter applications. In addition, an intelligent monitoring strategy for the separation of package-related wear......-out failure mechanisms has been proposed. By means of the proposed method, the wear-out failure mechanisms of an IGBT module can be separated without any additional efforts during the power cycling tests. The validity and effectiveness of the proposed monitoring strategy are also verified by experiments....

  11. Bringing together the work of subscription and open access specialists: challenges and changes at the University of Sussex

    Directory of Open Access Journals (Sweden)

    Eleanor Craig

    2017-03-01

    Full Text Available The rise in open access (OA publishing has required library staff across many UK academic institutions to take on new roles and responsibilities to support academics. At the same time, the long-established work of negotiating with publishers around journal subscriptions is changing as such deals now usually include OA payment or discount plans in many different forms that vary from publisher to publisher. This article outlines some of the issues we encountered at the University of Sussex Library whilst trying to pull together the newer strand of OA advocacy and funder compliance work with existing responsibilities for managing subscription deals. It considers the challenges faced in effectively bringing together Library staff with knowledge in these areas, and outlines the steps we have taken so far to ensure OA publishing is taken into account wherever appropriate.

  12. Effects of GABA[subscript A] Modulators on the Repeated Acquisition of Response Sequences in Squirrel Monkeys

    Science.gov (United States)

    Campbell, Una C.; Winsauer, Peter J.; Stevenson, Michael W.; Moerschbaecher, Joseph M.

    2004-01-01

    The present study investigated the effects of positive and negative GABA[subscript A] modulators under three different baselines of repeated acquisition in squirrel monkeys in which the monkeys acquired a three-response sequence on three keys under a second-order fixed-ratio (FR) schedule of food reinforcement. In two of these baselines, the…

  13. Regulation strategies for wind power fluctuations depending on demand in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Martin-Martinez, Sergio; Vigueras-Rodriguez, Antonio; Gomez-Lazaro, Emilio [Universidad de Castilla-La Mancha, Albacete (Spain). Energy Research Inst.; Fuentes, Juan Alvaro; Molina-Garcia, Angel [Cartagena Univ. (Spain). Dept. of Electrical Engineering

    2010-07-01

    Power systems need more flexibility as far as significant amounts of load are being covered by wind power. The variations of large wind power production impose some adverse effects on the power system. Some of these effects are the cycling losses on centralized units, discarded wind energy and increase of reserve requirements. Cycling losses derived from a non-optimal operation on great thermal and hydro power plants is an important issue produced by the stochastic wind power nature. Discarded wind energy is produced when the system can not assimilate all the wind power production. Reserve requirements are increased to keep the system balance with the secondary control. Different control functions have been developed for active power production. Some of them are balance control, delta control and power gradient limitation. Balance control consists in adjusting the production in steps to a set point constant production. The delta production constraint consists on limiting the current production to a fix delta power value below the possible production. This constraint is usually used for increasing the regulation capabilities in the wind farm. The Delta constraint can also be used jointly with the negative ramp limiting strategy, allowing then also to fix a maximum negative gradient for the cases in which the wind speed is decreasing and it is possible to limit that descend by reducing the delta value. The power gradient limiting strategy consists in a limitation of the maximum increasing gradient of the current production, i.e. it prevents the farm production from increasing too fast when the wind speed is rising or when the farm is to be started in high wind. It the wind speed is decreasing, then the constraint does not have any function. On the other hand, the negative ramp limiting strategy consists in a limitation of the maximum decreasing gradient of the current production. If the wind speed is increasing, then the constraint does not have any function. This

  14. Research on Control Strategy of Free-Piston Stirling Power Generating System

    Directory of Open Access Journals (Sweden)

    Jigui Zheng

    2017-10-01

    Full Text Available As a clean and fuel adaptive alternative power plant, the Stirling power generating system has drawn attention of experts and scholars in the energy field. In practical application, the instability of free-piston Stirling power generating system caused by abrupt load change is an inevitable problem. Thus, methods to improve the output frequency response and stability of the free-piston Stirling power generating system are necessary. The model of free-piston Stirling power generating system is built by isothermal analysis firstly, and the initial control strategy based on given voltage system is put forward. To further improve the performance of power system, a current feedback decoupling control strategy is proposed, and the mathematical model is established. The influence of full decoupled quadrature-direct (d-q axis currents is analyzed with respect to the output voltage adjusting time and fluctuation amplitude under the variations of piston displacement and output load. The simulation results show that the system performance is significantly improved, but the dynamic regulation lags caused by the decoupled current control still exist. To solve this problem and improve the performance of decoupled-state feedback current control that relies on parameter accuracy, internal model control based on sliding mode (IMC-SM current decoupling control strategy is proposed, the system model is established, and then the performance of voltage ripple in generating mode is improved. Finally, the test bench is built, and the steady state and transient voltage control performances are tested. The feasibility and priority of the control strategy is verified by experiment and simulation results.

  15. A New Generalized Discontinuous-PWM Strategy for Active Power Filters

    DEFF Research Database (Denmark)

    Asiminoaei, Lucian; Rodriguez, Pedro; Blaabjerg, Frede

    2007-01-01

    losses in any operating point. This paper proposes a new discontinuous pulse width modulation strategy applied to shunt active power filters. The proposed modulation strategy detects the current vector position relative to the inverter voltage reference and determines instantaneously the optimum clamped...

  16. Nuclear power development: global challenges and strategies

    International Nuclear Information System (INIS)

    Mourogov, Victor M.; )

    1997-01-01

    This article highlights key factors that will determine today and tomorrow's optimal energy strategies. It addresses methods to utilize the high potential energy content of uranium. Plutonium used as fuel in a nuclear reactors is discussed as is the future potential of a thorium fuel cycle. Various strategies to increase the economic viability of nuclear power are brought out. Technological means to further minimize environmental impacts and to enhance safety are covered as they are a major factor in public acceptance. Also covered are advances anticipated by mid-century in nuclear reactor and fuel cycle technologies

  17. Highly Radiative Plasmas for Local Transport Studies and Power and Particle Handling in Reactor Regimes

    International Nuclear Information System (INIS)

    Bell, M.G.; Bell, R.E.; Budny, R.; Bush, C.E.; Hill, K.W.

    1998-01-01

    To study the applicability of artificially enhanced impurity radiation for mitigation of the plasma-limiter interaction in reactor regimes, krypton and xenon gases were injected into the Tokamak Fusion Test Reactor (TFTR) supershots and high-l(subscript) plasmas. At neutral beam injection (NBI) powers P(subscript B) greater than or equal to 30 MW, carbon influxes (blooms) were suppressed, leading to improved energy confinement and neutron production in both deuterium (D) and deuterium-tritium (DT) plasmas, and the highest DT fusion energy production (7.6 MJ) in a TFTR pulse. Comparisons of the measured radiated power profiles with predictions of the MIST impurity transport code have guided studies of highly-radiative plasmas in the International Thermonuclear Experimental Reactor (ITER). The response of the electron and ion temperatures to greatly increased radiative losses from the electrons was used to study thermal transport mechanisms

  18. Keeping current, June 1998. Issues 98: Securing the value of the federal Columbia River power system

    International Nuclear Information System (INIS)

    1998-06-01

    This report focuses on issues which will enhance the value of the Columbia River for the future. Many important decisions must be made about the Bonneville Power Administration in the coming months. These issues include the following: cost management; future fish and wildlife funding; power markets, revenues and subscription; transmission issues; and risk management

  19. Securing the Value of the Federal Columbia River Power System, Keeping Current, June 1998, Issue 98.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1998-06-01

    This report focuses on issues which will enhance the value of the Columbia River for the future. Many important decisions must be made about the Bonneville Power Administration in the coming months. These issues include the following: cost management; future fish and wildlife funding; power markets, revenues and subscription; transmission issues; and risk management.

  20. Comparison among nonlinear excitation control strategies used for damping power system oscillations

    International Nuclear Information System (INIS)

    Leon, A.E.; Solsona, J.A.; Valla, M.I.

    2012-01-01

    Highlights: ► A description and comparison of nonlinear control strategies for synchronous generators are presented. ► Advantages of using nonlinear controllers are emphasized against the use of classical PSSs. ► We find that a particular selection of IDA gains achieve the same performance that FL controllers. - Abstract: This work is focused on the problem of power system stability. A thorough description of nonlinear control strategies for synchronous generator excitation, which are designed for damping oscillations and improving transient stability on power systems, is presented along with a detailed comparison among these modern strategies and current solutions based on power system stabilizers. The performance related to damping injection in each controller, critical time enhancement, robustness against parametric uncertainties, and control signal energy consumption is analyzed. Several tests are presented to validate discussions on various advantages and disadvantages of each control strategy.

  1. Turbine Control Strategies for Wind Farm Power Optimization

    DEFF Research Database (Denmark)

    Mirzaei, Mahmood; Göçmen Bozkurt, Tuhfe; Giebel, Gregor

    2015-01-01

    In recent decades there has been increasing interest in green energies, of which wind energy is the most important one. In order to improve the competitiveness of the wind power plants, there are ongoing researches to decrease cost per energy unit and increase the efficiency of wind turbines...... and wind farms. One way of achieving these goals is to optimize the power generated by a wind farm. One optimization method is to choose appropriate operating points for the individual wind turbines in the farm. We have made three models of a wind farm based on three difference control strategies...... the generated power by changing the power reference of the individual wind turbines. We use the optimization setup to compare power production of the wind farm models. This paper shows that for the most frequent wind velocities (below and around the rated values), the generated powers of the wind farms...

  2. Strategy Design of Hybrid Energy Storage System for Smoothing Wind Power Fluctuations

    Directory of Open Access Journals (Sweden)

    Jingyu Liu

    2016-11-01

    Full Text Available With the increasing contribution of wind power plants, the reliability and security of modern power systems have become a huge challenge due to the uncertainty and intermittency of wind energy sources. In this paper, a hybrid energy storage system (HESS consisting of battery and supercapacitor is built to smooth the power fluctuations of wind power. A power allocation strategy is proposed to give full play to the respective advantages of the two energy storage components. In the proposed strategy, the low-frequency and high-frequency components of wind power fluctuations are absorbed by battery groups and supercapacitor groups, respectively. By inhibiting the low-frequency components of supercapacitor current, the times of charging-discharging of battery groups can be significantly reduced. A DC/AC converter is applied to achieve the power exchange between the HESS and the grid. Adjustment rules for regulating state-of-charge (SOC of energy storage elements are designed to avoid overcharge and deep discharge considering the safety and the high efficiency of the energy storage elements. Experimental results on the test platform verify the effectiveness of the proposed power allocation strategy in DC/AC converter and battery SOC adjustment rules for regulating SOC levels.

  3. A real time fuzzy logic power management strategy for a fuel cell vehicle

    International Nuclear Information System (INIS)

    Hemi, Hanane; Ghouili, Jamel; Cheriti, Ahmed

    2014-01-01

    Highlights: • We present a real time fuzzy logic power management strategy. • This strategy is applied to hybrid electric vehicle dynamic model. • Three configurations evaluated during a drive cycle. • The hydrogen consumption is analysed for the three configurations. - Abstract: This paper presents real time fuzzy logic controller (FLC) approach used to design a power management strategy for a hybrid electric vehicle and to protect the battery from overcharging during the repetitive braking energy accumulation. The fuel cell (FC) and battery (B)/supercapacitor (SC) are the primary and secondary power sources, respectively. This paper analyzes and evaluates the performance of the three configurations, FC/B, FC/SC and FC/B/SC during real time driving conditions and unknown driving cycle. The MATLAB/Simulink and SimPowerSystems software packages are used to model the electrical and mechanical elements of hybrid vehicles and implement a fuzzy logic strategy

  4. Power Management Strategy of Hybrid Electric Vehicles Based on Quadratic Performance Index

    Directory of Open Access Journals (Sweden)

    Chaoying Xia

    2015-11-01

    Full Text Available An energy management strategy (EMS considering both optimality and real-time performance has become a challenge for the development of hybrid electric vehicles (HEVs in recent years. Previous EMSes based on the optimal control theory minimize the fuel consumption, but cannot be directly implemented in real-time because of the requirement for a prior knowledge of the entire driving cycle. This paper presents an innovative design concept and method to obtain a power management strategy for HEVs, which is independent of future driving conditions. A quadratic performance index is designed to ensure the vehicle drivability, maintain the battery energy sustainability and average and smooth the engine power and motor power to indirectly reduce fuel consumption. To further improve the fuel economy, two rules are adopted to avoid the inefficient engine operation by switching control modes between the electric and hybrid modes according to the required driving power. The derived power of the engine and motor are related to current vehicle velocity and battery residual energy, as well as their desired values. The simulation results over different driving cycles in Advanced Vehicle Simulator (ADVISOR show that the proposed strategy can significantly improve the fuel economy, which is very close to the optimal strategy based on Pontryagin’s minimum principle.

  5. Rio Branco, grand strategy and naval power

    Directory of Open Access Journals (Sweden)

    João Paulo Alsina Jr.

    2014-12-01

    Full Text Available This article addresses Baron of Rio Branco's grand strategy and the role played by the naval reorganization program (1904-1910 in this context. The ensuing case study determined the domestic and international constraints that affected the program, as well as the worldview of the patron of Brazilian diplomacy regarding military power's instrumentality to foreign policy.

  6. The A[subscript 1c] Blood Test: An Illustration of Principles from General and Organic Chemistry

    Science.gov (United States)

    Kerber, Robert C.

    2007-01-01

    The glycated hemoglobin blood test, usually designated as the A[subscript 1c] test, is a key measure of the effectiveness of glucose control in diabetics. The chemistry of glucose in the bloodstream, which underlies the test and its impact, provides an illustration of the importance of chemical equilibrium and kinetics to a major health problem.…

  7. Statistical power of model selection strategies for genome-wide association studies.

    Directory of Open Access Journals (Sweden)

    Zheyang Wu

    2009-07-01

    Full Text Available Genome-wide association studies (GWAS aim to identify genetic variants related to diseases by examining the associations between phenotypes and hundreds of thousands of genotyped markers. Because many genes are potentially involved in common diseases and a large number of markers are analyzed, it is crucial to devise an effective strategy to identify truly associated variants that have individual and/or interactive effects, while controlling false positives at the desired level. Although a number of model selection methods have been proposed in the literature, including marginal search, exhaustive search, and forward search, their relative performance has only been evaluated through limited simulations due to the lack of an analytical approach to calculating the power of these methods. This article develops a novel statistical approach for power calculation, derives accurate formulas for the power of different model selection strategies, and then uses the formulas to evaluate and compare these strategies in genetic model spaces. In contrast to previous studies, our theoretical framework allows for random genotypes, correlations among test statistics, and a false-positive control based on GWAS practice. After the accuracy of our analytical results is validated through simulations, they are utilized to systematically evaluate and compare the performance of these strategies in a wide class of genetic models. For a specific genetic model, our results clearly reveal how different factors, such as effect size, allele frequency, and interaction, jointly affect the statistical power of each strategy. An example is provided for the application of our approach to empirical research. The statistical approach used in our derivations is general and can be employed to address the model selection problems in other random predictor settings. We have developed an R package markerSearchPower to implement our formulas, which can be downloaded from the

  8. Comparison of the Velocity and Power Parameters during Loaded-Squat Jump Exercise of National Athletes in Different Branches*

    Science.gov (United States)

    Can, Ibrahim; Cihan, Hamit; Ari, Erdal; Bayrakdaroglu, Serdar

    2018-01-01

    The aim of this investigation is to compare velocity and power variables during loaded-squat jump (SJ[subscript Loaded]) exercise of national athletes dealing with different sports branches and to identify whether velocity and power parameters become different or not according to branches. In accordance with this purpose, a total of 36 national…

  9. Research on wind power grid-connected operation and dispatching strategies of Liaoning power grid

    Science.gov (United States)

    Han, Qiu; Qu, Zhi; Zhou, Zhi; He, Xiaoyang; Li, Tie; Jin, Xiaoming; Li, Jinze; Ling, Zhaowei

    2018-02-01

    As a kind of clean energy, wind power has gained rapid development in recent years. Liaoning Province has abundant wind resources and the total installed capacity of wind power is in the forefront. With the large-scale wind power grid-connected operation, the contradiction between wind power utilization and peak load regulation of power grid has been more prominent. To this point, starting with the power structure and power grid installation situation of Liaoning power grid, the distribution and the space-time output characteristics of wind farm, the prediction accuracy, the curtailment and the off-grid situation of wind power are analyzed. Based on the deep analysis of the seasonal characteristics of power network load, the composition and distribution of main load are presented. Aiming at the problem between the acceptance of wind power and power grid adjustment, the scheduling strategies are given, including unit maintenance scheduling, spinning reserve, energy storage equipment settings by the analysis of the operation characteristics and the response time of thermal power units and hydroelectric units, which can meet the demand of wind power acceptance and provide a solution to improve the level of power grid dispatching.

  10. Capacity subscription and its market design impact

    International Nuclear Information System (INIS)

    Doorman, Gerard; Solem, Gerd

    2005-04-01

    Capacity Subscription (CS) implies that consumers buy (subscribe to) a certain amount of capacity. Their demand is limited to this capacity when the total power system is short of capacity and the System Operator activates controllable Load Limiting Devices (LLDs). The objective is to maintain system security by avoiding involuntary load shedding. The report describes a market design with CS. As a case study, an analysis is made of the changes in the market design of the Nordic system that would be necessary to implement CS. First the present Nordic market design is described. Focus is on the various market participants, their roles within various time horizons and their interactions. So it is described how CS works, why it works and what is necessary to make it work. Subsequently the necessary changes in the Nordic market structure are described. The major changes are the installation of the LLDs, the establishment of the necessary infrastructure to control the LLDs and the rules governing their control and the establishment of a capacity market. The major rule is that the System Operator announces LLD activation when a shortage situation is expected. In the capacity market generators offer available capacity during system peak conditions, while consumers bid their need for capacity. Market participants are the same as on the spot market, while small consumers buy through retailer. Generators are obliged to offer the capacity sold on the capacity market on the spot market during LLD activation. Failure to do so results in a penalty payment. The report further discusses issues like the need for verification procedures, import and export, generation pooling, the handling of small consumers, reserves and a possible implementation path of CS. With respect to transmission constraints it is argued that market splitting can be a viable option. It is concluded that CS can be a possible solution to maintain generation adequacy, but there are some serious challenges. The

  11. Blowing in the Wind: A Review of Wind Power Technology

    Science.gov (United States)

    Harris, Frank

    2014-01-01

    The use of wind as a replenishable energy resource has come back into favour in recent decades. It is much promoted as a viable, clean energy option that will help towards reducing CO[subscript 2] emissions in the UK. This article examines the history of wind power and considers the development of wind turbines, together with their economic,…

  12. Power Stabilization Strategy of Random Access Loads in Electric Vehicles Wireless Charging System at Traffic Lights

    Directory of Open Access Journals (Sweden)

    Linlin Tan

    2016-10-01

    Full Text Available An opportunity wireless charging system for electric vehicles when they stop and wait at traffic lights is proposed in this paper. In order to solve the serious power fluctuation caused by random access loads, this study presents a power stabilization strategy based on counting the number of electric vehicles in a designated area, including counting method, power source voltage adjustment strategy and choice of counting points. Firstly, the circuit model of a wireless power system with multi-loads is built and the equation of each load is obtained. Secondly, after the counting method of electric vehicles is stated, the voltage adjustment strategy, based on the number of electric vehicles when the system is at a steady state, is set out. Then, the counting points are chosen according to power curves when the voltage adjustment strategy is adopted. Finally, an experimental prototype is implemented to verify the power stabilization strategy. The experimental results show that, with the application of this strategy, the charging power is stabilized with the fluctuation of no more than 5% when loads access randomly.

  13. Security strategy of powered-off SRAM for resisting physical attack to data remanence

    International Nuclear Information System (INIS)

    Yu Kai; Zou Xuecheng; Yu Guoyi; Wang Weixu

    2009-01-01

    This paper presents a security strategy for resisting a physical attack utilizing data remanence in powered-off static random access memory (SRAM). Based on the mechanism of physical attack to data remanence, the strategy intends to erase data remanence in memory cells once the power supply is removed, which disturbs attackers trying to steal the right information. Novel on-chip secure circuits including secure power supply and erase transistor are integrated into conventional SRAM to realize erase operation. Implemented in 0.25 μm Huahong-NEC CMOS technology, an SRAM exploiting the proposed security strategy shows the erase operation is accomplished within 0.2 μs and data remanence is successfully eliminated. Compared with conventional SRAM, the retentive time of data remanence is reduced by 82% while the operation power consumption only increases by 7%.

  14. Frequency Control Strategy for Black Starts via PMSG-Based Wind Power Generation

    Directory of Open Access Journals (Sweden)

    Yi Tang

    2017-03-01

    Full Text Available The use of wind power generation (WPG as a source for black starts will significantly enhance the resiliency of power systems and shorten their recovery time from blackouts. Given that frequency stability is the most serious issue during the initial recovery period, virtual inertia control can enable wind turbines to provide frequency support to an external system. In this study, a general procedure of WPG participating in black starts is presented, and the key issues are discussed. The adaptability of existing virtual inertia control strategies is analyzed, and improvement work is performed. A new coordinated frequency control strategy is proposed based on the presented improvement work. A local power network with a permanent-magnet synchronous generator (PMSG-based wind farm is modeled and used to verify the effectiveness of the strategy.

  15. The sales strategies of electric power and natural gas in France

    International Nuclear Information System (INIS)

    Heddebaut, D.

    2005-01-01

    This study presents a whole panorama of the commercial strategies developed by the electric power and natural gas suppliers. Based on interviews, this study provides data keys and development strategies of 13 operators of the energy french market. (A.L.B.)

  16. Best control strategy for unified power quality conditioner (UPQC) based on simulation

    Energy Technology Data Exchange (ETDEWEB)

    Shayanfar, H.A. [Iran Univ. of Science and Technology, Tehran (Iran, Islamic Republic of). Dept. of Electrical Engineering; Tabatabaei, N.M. [Azarbaijan Univ. of Tarbiat Moallem, Tabriz (Iran, Islamic Republic of). Dept. of Electrical Engineering; Mokhtarpour, A. [Islamic Azad Univ., Tabriz (Iran, Islamic Republic of). Dept. of Electrical Engineering

    2007-07-01

    Electronic devices used in both industry and residences need high-quality energy to work properly. Unified Power Quality Conditioners (UPQC) solve any power quality problems faced by these devices. Three new control strategies for UPQCs were presented and their operation was investigated and compared using the MATLAB Simulink simulation software package. A UPQC consists of a Shunt-Active Filter and a Series Active Filter with a common direct current link to compensate for any source currents and delivered voltage to the load. As such, it isolates the utility from current quality problems associated with load. It also isolates the load from the voltage quality problems of the utility. In the first control strategy, the Parallel Active Filter (PAF) and Series Active Filter (SAF) are based on the Fourier transform theory. In the second control strategy, the Parallel Active Filter is based on the power quality theory and the Series Active Filter is based on the Fourier transform theory. In the third control strategy, the Parallel Active Filter is based on Fourier transform theory and the Series Active Filter is based on positive sequence detection. Operating the PAF using these methods compensates for reactive power and current harmonics, while operating the SAF compensates for imbalances, voltage harmonics and positive and zero sequences of utility voltages. MATLAB simulation software was used to explain the compensation resolution and speed of the 3 new control strategies. According to simulation test results, it was concluded that the best compensation speed and resolution can be obtained using the third control strategy. 7 refs., 2 tabs., 24 figs.

  17. LHC Inner Triplet Powering Strategy

    CERN Document Server

    Bordry, Frederick

    2001-01-01

    In order to achieve a luminosity in excess of 10**34 cm**-2s**-1 at the Large Hadron Collider (LHC), special high gradient quadrupoles are required for the final focusing triplets. These low-b triplets, located in the four experimental insertions (ATLAS, CMS, ALICE, LHC-B), consist of four wide-aperture superconducting magnets: two outer quadrupoles, Q1 and Q3, with a maximum current of 7 kA and a central one divided into two identical magnets, Q2a and Q2b, with a maximum current of 11.5 kA. To optimise the powering of these mixed quadrupoles, it was decided to use two nested high-current power converters : [8kA, 8V] and [6kA, 8V]. This paper presents the consequence of the interaction between the two galvanically coupled circuits. A control strategy, using two independent, standard, LHC digital controllers, to decouple the two systems is proposed and described. The converter protection during the discharge of the magnet energy due to quenches or interlocks of the magnets are discussed. Simulation and experim...

  18. Short-term strategies for Dutch wind power producers to reduce imbalance costs

    International Nuclear Information System (INIS)

    Chaves-Ávila, José Pablo; Hakvoort, Rudi A.; Ramos, Andrés

    2013-01-01

    The paper assesses bidding strategies for a wind power producer in the Netherlands. To this end, a three-stage stochastic optimization framework is used, maximizing wind power producer's profit using the day-ahead and cross-border intraday market, taking into account available interconnection capacity. Results show that the wind power producer can increase its profits by trading on the intraday market and – under certain imbalance prices – by intentionally creating imbalances. It has been considered uncertainties about prices, power forecast and interconnection capacity at the day-ahead and intraday timeframes. - Highlights: ► A cross-border bidding strategy model for wind power producers has been developed. ► The model was applied to a real case study of a Dutch offshore wind power producer. ► Under certain imbalance prices, it is not profitable to deliver all possible power. ► Intraday markets give the possibility to reduce imbalance costs. ► Integration of intraday markets will increase liquidity.

  19. Management of fluctuations in wind power and CHP comparing two possible Danish strategies

    International Nuclear Information System (INIS)

    Lund, H.; Clark, W.W.

    2002-01-01

    Both CHP (combined heat and power production) and wind power are important elements of Danish energy policy. Today, approximately 50% of both the Danish electricity and heat demand are produced in CHP and more than 15% of the electricity demand is produced by wind turbines. Both technologies are essential for the implementation of Danish climate change response objectives, and both technologies are intended for further expansion in the coming decade. Meanwhile, the integration of CHP and wind power is subject to fluctuations in electricity production. Wind turbines depend on the wind, and CHP depends on the heat demand. This article discusses and analyses two different national strategies for solving this problem. One strategy, which is the current official government policy known as the export strategy, proposes to take advantage of the Nordic and European markets for selling and buying electricity. In this case, surplus electricity from wind power and CHP simply will be sold to neighbouring countries. Another strategy, the self-supply strategy, runs the CHP units to meet both demand and the fluctuations in the wind scheduling. In this case, investments in heat storages are necessary and heat pumps have to be added to the CHP units. Based on official Danish energy policy and energy plans, this article quantifies the problem for the year 2015 in terms of the amount of surplus electricity, and investments in heat pumps, etc. needed to solve the problem are calculated. Based on these results between the two different strategies, the conclusion is that the self-supply strategy is recommended over the official export strategy. (author)

  20. A Fuzzy-Logic Power Management Strategy Based on Markov Random Prediction for Hybrid Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    Yanzi Wang

    2016-01-01

    Full Text Available Over the last few years; issues regarding the use of hybrid energy storage systems (HESSs in hybrid electric vehicles have been highlighted by the industry and in academic fields. This paper proposes a fuzzy-logic power management strategy based on Markov random prediction for an active parallel battery-UC HESS. The proposed power management strategy; the inputs for which are the vehicle speed; the current electric power demand and the predicted electric power demand; is used to distribute the electrical power between the battery bank and the UC bank. In this way; the battery bank power is limited to a certain range; and the peak and average charge/discharge power of the battery bank and overall loss incurred by the whole HESS are also reduced. Simulations and scaled-down experimental platforms are constructed to verify the proposed power management strategy. The simulations and experimental results demonstrate the advantages; feasibility and effectiveness of the fuzzy-logic power management strategy based on Markov random prediction.

  1. Control strategy research of two stage topology for pulsed power supply

    International Nuclear Information System (INIS)

    Shi Chunfeng; Wang Rongkun; Huang Yuzhen; Chen Youxin; Yan Hongbin; Gao Daqing

    2013-01-01

    A kind of pulsed power supply of HIRFL-CSR was introduced, the ripple and the current error of the topological structure of the power in the operation process were analyzed, and two stage topology of pulsed power supply was given. The control strategy was simulated and the experiment was done in digital power platform. The results show that the main circuit structure and control method are feasible. (authors)

  2. Maximum wind energy extraction strategies using power electronic converters

    Science.gov (United States)

    Wang, Quincy Qing

    2003-10-01

    This thesis focuses on maximum wind energy extraction strategies for achieving the highest energy output of variable speed wind turbine power generation systems. Power electronic converters and controls provide the basic platform to accomplish the research of this thesis in both hardware and software aspects. In order to send wind energy to a utility grid, a variable speed wind turbine requires a power electronic converter to convert a variable voltage variable frequency source into a fixed voltage fixed frequency supply. Generic single-phase and three-phase converter topologies, converter control methods for wind power generation, as well as the developed direct drive generator, are introduced in the thesis for establishing variable-speed wind energy conversion systems. Variable speed wind power generation system modeling and simulation are essential methods both for understanding the system behavior and for developing advanced system control strategies. Wind generation system components, including wind turbine, 1-phase IGBT inverter, 3-phase IGBT inverter, synchronous generator, and rectifier, are modeled in this thesis using MATLAB/SIMULINK. The simulation results have been verified by a commercial simulation software package, PSIM, and confirmed by field test results. Since the dynamic time constants for these individual models are much different, a creative approach has also been developed in this thesis to combine these models for entire wind power generation system simulation. An advanced maximum wind energy extraction strategy relies not only on proper system hardware design, but also on sophisticated software control algorithms. Based on literature review and computer simulation on wind turbine control algorithms, an intelligent maximum wind energy extraction control algorithm is proposed in this thesis. This algorithm has a unique on-line adaptation and optimization capability, which is able to achieve maximum wind energy conversion efficiency through

  3. QoE-based transmission strategies for multi-user wireless information and power transfer

    Directory of Open Access Journals (Sweden)

    Taehun Jung

    2015-12-01

    Full Text Available One solution to the problem of supplying energy to wireless networks is wireless power transfer. One such technology–electromagnetic radiation enabled wireless power transfer–will change traditional wireless networks. In this paper, we investigate a transmission strategy for multi-user wireless information and power transfer. We consider a multi-user multiple-input multiple-output (MIMO channel that includes one base station (BS and two user terminals (UT consisting of one energy harvesting (EH receiver and one information decoding (ID receiver. Our system provides transmission strategies that can be executed and implemented in practical scenarios. The paper then analyzes the rate–energy (R–E pair of our strategies and compares them to those of the theoretical optimal strategy. We furthermore propose a QoE-based mode selection algorithm by mapping the R–E pair to the utility functions.

  4. Bomber Deployments: A New Power Projection Strategy

    Science.gov (United States)

    2016-08-21

    AIR COMMAND AND STAFF COLLEGE DISTANCE LEARNING AIR UNIVERSITY BOMBER DEPLOYMENTS: A NEW POWER PROJECTION STRATEGY by...operating base (FOB), main operating base ( MOB ) and intermediate staging base (ISB).10 Each type of base requires certain actions to make it suitable for...closure of many main operating bases ( MOB ) overseas and the reluctance of many nations to permit permanent military bases on their soil.”15 This

  5. Review of reactive power dispatch strategies for loss minimization in a DFIG-based wind farm

    DEFF Research Database (Denmark)

    Zhang, Baohua; Hu, Weihao; Hou, Peng

    2017-01-01

    power control strategies are investigated. All of the combined strategies are formulated based on the comprehensive loss models of WFs, including the loss models of DFIGs, converters, filters, transformers, and cables of the collection system. Optimization problems are solved by a Modified Particle......This paper reviews and compares the performance of reactive power dispatch strategies for the loss minimization of Doubly Fed Induction Generator (DFIG)-based Wind Farms (WFs). Twelve possible combinations of three WF level reactive power dispatch strategies and fourWind Turbine (WT) level reactive...... Swarm Optimization (MPSO) algorithm. The effectiveness of these strategies is evaluated by simulations on a carefully designed WF under a series of cases with different wind speeds and reactive power requirements of the WF. The wind speed at each WT inside the WF is calculated using the Jensen wake...

  6. Power flow control strategy in distribution network for dc type distributed energy resource at load bus

    International Nuclear Information System (INIS)

    Hanif, A.; Choudhry, M.A.

    2013-01-01

    This research work presents a feed forward power flow control strategy in the secondary distribution network working in parallel with a DC type distributed energy resource (DER) unit with SPWM-IGBT Voltage Source Converter (VSC). The developed control strategy enables the VSC to be used as power flow controller at the load bus in the presence of utility supply. Due to the investigated control strategy, power flow control from distributed energy resource (DER) to common load bus is such that power flows to the load without facing any power quality problem. The technique has an added advantage of controlling power flow without having a dedicated power flow controller. The SPWM-IGBT VSC is serving the purpose of dc-ac converter as well as power flow controller. Simulations for a test system using proposed power flow control strategy are carried out using SimPower Systems toolbox of MATLAB at the rate and Simulink at the rate. The results show that a reliable, effective and efficient operation of DC type DER unit in coordination with main utility network can be achieved. (author)

  7. An improved power control strategy for hybrid AC-DC microgrids

    DEFF Research Database (Denmark)

    Baharizadeh, Mehdi; Karshenas, Hamid Reza; Guerrero, Josep M.

    2018-01-01

    This paper presents a new droop-based control strategy for hybrid microgrids (HMG) with improved power sharing. When ac microgrids (AC-MG) and dc microgrids (DC-MG) are present in a distribution grid, there is an opportunity to interconnect them via an interlinking converter (IC) and form a HMG......, the possibility of participation of IC in AC-MG reactive power adds some complexity to a HMG control system. In this paper, a new decentralized control strategy is presented for a HMG which relies on regulating the voltage magnitude of a common bus in each microgrid. In this regard, new droop characteristics...... for sources across both microgrids as well as IC are proposed. The proposed droop characteristics result in better active/reactive power sharing across both microgrids and at the same time results in better voltage regulation. The derivation of new droop characteristics is thoroughly discussed in this paper...

  8. Pool Strategy of a Price-Maker Wind Power Producer

    DEFF Research Database (Denmark)

    Zugno, Marco; Morales González, Juan Miguel; Pinson, Pierre

    2013-01-01

    We consider the problem of a wind power producer trading energy in short-term electricity markets. The producer is a price-taker in the day-ahead market, but a price-maker in the balancing market, and aims at optimizing its expected revenues from these market floors. The problem is formulated...... or median forecast of wind power distribution. Finally, sensitivity analyses are carried out to assess the impact on the offering strategy of the producer's penetration in the market, of the correlation between wind power production and residual system deviation, and of the shape of the forecast...

  9. Fault analysis and strategy of high pulsed power supply for high power laser

    International Nuclear Information System (INIS)

    Liu Kefu; Qin Shihong; Li Jin; Pan Yuan; Yao Zonggan; Zheng Wanguo; Guo Liangfu; Zhou Peizhang; Li Yizheng; Chen Dehuai

    2001-01-01

    according to the requirements of driving flash-lamp, a high pulsed power supply (PPS) based on capacitors as energy storage elements is designed. The author analyzes in detail the faults of high pulsed power supply for high power laser. Such as capacitor internal short-circuit, main bus breakdown to ground, flashlamp sudden short or break. The fault current and voltage waveforms were given by circuit simulations. Based on the analysis and computation, the protection strategy with the fast fuse and ZnO was put forward, which can reduce the damage of PPS to the lower extent and provide the personnel safe and collateral property from the all threats. The preliminary experiments demonstrated that the design of the PPS can satisfy the project requirements

  10. Coordinated Control Strategies of VSC-HVDC-Based Wind Power Systems for Low Voltage Ride Through

    Directory of Open Access Journals (Sweden)

    Xinyin Zhang

    2015-07-01

    Full Text Available The Voltage Source Converter-HVDC (VSC-HVDC system applied to wind power generation can solve large scale wind farm grid-connection and long distance transmission problems. However, the low voltage ride through (LVRT of the VSC-HVDC connected wind farm is a key technology issue that must be solved, and it is currently lacking an economic and effective solution. In this paper, a LVRT coordinated control strategy is proposed for the VSC-HVDC-based wind power system. In this strategy, the operation and control of VSC-HVDC and wind farm during the grid fault period is improved. The VSC-HVDC system not only provides reactive power support to the grid, but also effectively maintains the power balance and DC voltage stability by reducing wind-farm power output, without increasing the equipment investment. Correspondingly, to eliminate the influence on permanent magnet synchronous generator (PMSG-based wind turbine (WT systems, a hierarchical control strategy is designed. The speed and validity of the proposed LVRT coordinated control strategy and hierarchical control strategy were verified by MATLAB/Simulink simulations.

  11. The Effect of Teachers' Memory-Relevant Language on Children's Strategy Use and Knowledge

    Science.gov (United States)

    Grammer, Jennie; Coffman, Jennifer L.; Ornstein, Peter

    2013-01-01

    Building on longitudinal findings of linkages between aspects of teachers' language during instruction and children's use of mnemonic strategies, this investigation was designed to examine experimentally the impact of instruction on memory development. First and second graders ("N" = 54, "M"[subscript age] = 7 years)…

  12. PEMFC Optimization Strategy with Auxiliary Power Source in Fuel Cell Hybrid Vehicle

    Directory of Open Access Journals (Sweden)

    Tinton Dwi Atmaja

    2012-02-01

    Full Text Available Page HeaderOpen Journal SystemsJournal HelpUser You are logged in as...aulia My Journals My Profile Log Out Log Out as UserNotifications View (27 new ManageJournal Content SearchBrowse By Issue By Author By Title Other JournalsFont SizeMake font size smaller Make font size default Make font size largerInformation For Readers For Authors For LibrariansKeywords CBPNN Displacement FLC LQG/LTR Mixed PMA Ventilation bottom shear stress direct multiple shooting effective fuzzy logic geoelectrical method hourly irregular wave missile trajectory panoramic image predator-prey systems seawater intrusion segmentation structure development pattern terminal bunt manoeuvre Home About User Home Search Current Archives ##Editorial Board##Home > Vol 23, No 1 (2012 > AtmajaPEMFC Optimization Strategy with Auxiliary Power Source in Fuel Cell Hybrid VehicleTinton Dwi Atmaja, Amin AminAbstractone of the present-day implementation of fuel cell is acting as main power source in Fuel Cell Hybrid Vehicle (FCHV. This paper proposes some strategies to optimize the performance of Polymer Electrolyte Membrane Fuel Cell (PEMFC implanted with auxiliary power source to construct a proper FCHV hybridization. The strategies consist of the most updated optimization method determined from three point of view i.e. Energy Storage System (ESS, hybridization topology and control system analysis. The goal of these strategies is to achieve an optimum hybridization with long lifetime, low cost, high efficiency, and hydrogen consumption rate improvement. The energy storage system strategy considers battery, supercapacitor, and high-speed flywheel as the most promising alternative auxiliary power source. The hybridization topology strategy analyzes the using of multiple storage devices injected with electronic components to bear a higher fuel economy and cost saving. The control system strategy employs nonlinear control system to optimize the ripple factor of the voltage and the current

  13. Resins characterization strategy at Kozloduy Nuclear Power Plant

    International Nuclear Information System (INIS)

    Fenoy, A.; González, R.; Molleda, P.; Sánchez, L.; Herrera, J.

    2013-01-01

    The Consortium ENSA- Gas Natural Fenosa Engineering has a contract with Kozloduy Nuclear Power Plant (KNPP) for the retrieval and conditioning of the resins. Before that, the project deals with resins characterization to verify the fulfillment the Bulgarian authorities’ requirements. The project includes all the resins generated during the operation of the BACKGROUND Resins characterization strategy at Kozloduy Nuclear Power Plant units 1, 2, 3 and 4, which were stored into six big dimensions tanks: four low tanks and two intermediate tanks. They only have a manhole above for tanks access. The methodology and the progress of the work are presented

  14. Optimum investment strategy in the power industry mathematical models

    CERN Document Server

    Bartnik, Ryszard; Hnydiuk-Stefan, Anna

    2016-01-01

    This book presents an innovative methodology for identifying optimum investment strategies in the power industry. To do so, it examines results including, among others, the impact of oxy-fuel technology on CO2 emissions prices, and the specific cost of electricity production. The technical and economic analysis presented here extend the available knowledge in the field of investment optimization in energy engineering, while also enabling investors to make decisions involving its application. Individual chapters explore the potential impacts of different factors like environmental charges on costs connected with investments in the power sector, as well as discussing the available technologies for heat and power generation. The book offers a valuable resource for researchers, market analysts, decision makers, power engineers and students alike.

  15. Some characteristics of the Hungarian power systems long term expansion strategy

    International Nuclear Information System (INIS)

    Fazekas, A.

    1995-01-01

    The formulation of the power system expansion strategy meeting the targets of the Hungarian energy policy is justified by the ageing of the existing power plants, the technology change unavoidable because of the more and more rigorous environment protection regulations, the requirement of updating and by the compliance with the expectation of safe electric power supply. These requirements (fuel supply and diversification, economic considerations, operational and environmental considerations) call for the construction of new power plant units even if the demand for electric power would not show any further increase in future. 1 tab

  16. Economical analysis of an alternative strategy for CO2 mitigation based on nuclear power

    International Nuclear Information System (INIS)

    Alonso, Gustavo; Valle, Edmundo del

    2013-01-01

    Many countries are pursuing greenhouse gas (GHG) mitigation policies resulting in the increase of use of renewable sources in the electricity sector to mitigate CO 2 emissions. Nuclear energy is a non-emitting CO 2 source that could be used as part of that policy. However, its main drawback is the high investment required for its deployment. On the other hand, wind power is the clean source preferred option to mitigate CO 2 emissions. However, due to its intermittence backup power is needed, in most of the cases it must be provided with combined cycle thermal plants using natural gas. This study performs an economical comparison of a hypothetical implementation of a nuclear strategy to meet the same CO 2 emissions reduction goal that has been obtained by the actual Spaniard strategy (2005–2010) based on wind power. The investment required in both strategies is assessed under different investment scenarios and electricity production conditions for nuclear power. Also, the cost of electricity generation is compared for both strategies. - Highlights: ► Wind power electricity cost including its backup in Spain is assessed. ► Nuclear power is proposed as an alternative to produce the same CO 2 reduction. ► Nuclear power requires less installed capacity deployment. ► Investment to produce the same CO 2 reduction is smaller using nuclear power. ► Electricity generating cost is less expensive using the nuclear option

  17. Power Electronics Design of a Solar Powered In-car Wireless Tag for Asset Tracking and Parking Applications

    Science.gov (United States)

    Zhu, D.; Henaut, J.; Beeby, S. P.

    2014-11-01

    This paper reports the design and testing of a power conditioning circuit for a solar powered in-car wireless tag for asset tracking and parking application. Existing long range asset tracking is based on the GSM/GPRS network, which requires expensive subscriptions. The EU FP7 project CEWITT aims at developing a credit card sized autonomous wireless tag with GNSS geo-positioning capabilities to ensure the integrity and cost effectiveness for parking applications. It was found in previous research that solar cells are the most suitable energy sources for this application. This study focused on the power electronics design for the wireless tag. A suitable solar cell was chosen for its high power density. Charging circuit, hysteresis control circuit and LDO were designed and integrated to meet the system requirement. Test results showed that charging efficiency of 80 % had been achieved.

  18. Power Electronics Design of a Solar Powered In-car Wireless Tag for Asset Tracking and Parking Applications

    International Nuclear Information System (INIS)

    Zhu, D; Beeby, S P; Henaut, J

    2014-01-01

    This paper reports the design and testing of a power conditioning circuit for a solar powered in-car wireless tag for asset tracking and parking application. Existing long range asset tracking is based on the GSM/GPRS network, which requires expensive subscriptions. The EU FP7 project CEWITT aims at developing a credit card sized autonomous wireless tag with GNSS geo-positioning capabilities to ensure the integrity and cost effectiveness for parking applications. It was found in previous research that solar cells are the most suitable energy sources for this application. This study focused on the power electronics design for the wireless tag. A suitable solar cell was chosen for its high power density. Charging circuit, hysteresis control circuit and LDO were designed and integrated to meet the system requirement. Test results showed that charging efficiency of 80 % had been achieved

  19. Economics of Scholarly Publishing: Exploring the Causes of Subscription Price Variations of Scholarly Journals in Business Subject-Specific Areas

    Science.gov (United States)

    Liu, Lewis G.

    2011-01-01

    This empirical research investigates subscription price variations of scholarly journals in five business subject-specific areas using the semilogarithmic regression model. It has two main purposes. The first is to address the unsettled debate over whether or not and to what extent commercial publishers reap monopoly profits by overcharging…

  20. RF Power Transfer, Energy Harvesting, and Power Management Strategies

    Science.gov (United States)

    Abouzied, Mohamed Ali Mohamed

    sources in the far field, dc energy combining, wireless power transfer in the near field, the underlying power management strategies, and the integration on silicon. This integration is the ultimate goal for cheap solutions to enable the technology for broader use. All systems were designed, implemented and tested to demonstrate proof-of concept prototypes.

  1. Optimized control strategy for crowbarless solid state modular power supply

    International Nuclear Information System (INIS)

    Upadhyay, R.; Badapanda, M.K.; Tripathi, A.; Hannurkar, P.R.; Pithawa, C.K.

    2009-01-01

    Solid state modular power supply with series connected IGBT based power modules have been employed as high voltage bias power supply of klystron amplifier. Auxiliary compensation of full wave inverter bridge with ZVS/ZCS operations of all IGBTs over entire operating range is incorporated. An optimized control strategy has been adopted for this power supply needing no output filter, making this scheme crowbarless and is presented in this paper. DSP based fully digital control with same duty cycle for all power modules, have been incorporated for regulating this power supply along with adequate protection features. Input to this power supply is taken directly from 11 kV line and the input system is intentionally made 24 pulsed to reduce the input harmonics, improve the input power factor significantly, there by requiring no line filters. Various steps have been taken to increase the efficiency of major subsystems, so as to improve the overall efficiency of this power supply significantly. (author)

  2. Power generation assets. Energy constraints, upper bounds and hedging strategies

    Energy Technology Data Exchange (ETDEWEB)

    Enge, Thomas

    2010-09-20

    The overall topic of this thesis is the valuation of power generation assets under energy and risk constraints. Our focus is on the modeling aspect i.e. to find the right balance between accuracy and computational feasibility. We define a new not yet investigated unit commitment problem that introduces an energy constraint to a thermal power plant. We define a continuous stochastic dynamic program with a nested mixed integer program (MIP). We introduce a fast implementation approach by replacing the MIP with an efficient matrix calculation and use principal component analysis to reduce the number of risk factors. We also provide a fast heuristic valuation approach for comparison. As both models can only provide lower bounds of the asset value, we investigate the theory of upper bounds for a proper validation of our power plant results. We review the primal dual algorithm for swing options by Meinshausen and Hambly and in particular clarify their notation and implementation. Then we provide an extension for swing options with multiple exercises at the same stage that we developed together with Prof. Bender, University of Braunschweig. We outline Prof. Bender's proof and describe the implementation in detail. Finally we provide a risk analysis for our thermal power plant. In particular we investigate strategies to reduce spot price risk to which power plants are significantly exposed. First, we focus on the measurement of spot price risk and propose three appropriate risk figures (Forward delta as opposed to Futures delta, synthetic spot delta and Earnings-at-Risk) and illustrate their application using a business case. Second we suggest risk mitigation strategies for both periods, before and in delivery. The latter tries to alter the dispatch policy i.e. pick less risky hours and accept a (desirably only slightly) smaller return. We introduce a benchmark that weighs risk versus return and that we will call EaR-efficient option value. We propose a mitigation

  3. Smart — STATCOM control strategy implementation in wind power plants

    DEFF Research Database (Denmark)

    Sintamarean, Nicolae Christian; Cantarellas, Antoni Mir; Miranda, H.

    2012-01-01

    High penetration of wind energy into the grid may introduce stability and power quality problems due to the fluctuating nature of the wind and the increasing complexity of the power system. By implementing advanced functionalities in power converters, it is possible to improve the performance...... of the wind farm and also to provide grid support, as it is required by the grid codes. One of the main compliance difficulties that can be found in such power plants are related to reactive power compensation and to keep the harmonics content between the allowed limits, even if the power of the WPP...... converters is increasing. This paper deals with an advanced control strategy design of a three-level converter performing STATCOM and Active Filter functionalities. The proposed system is called Smart-STATCOM since it has the capability of self-controlling reactive power and harmonic voltages at the same...

  4. Power Flow Distribution Strategy for Improved Power Electronics Energy Efficiency in Battery Storage Systems: Development and Implementation in a Utility-Scale System

    Directory of Open Access Journals (Sweden)

    Michael Schimpe

    2018-03-01

    Full Text Available Utility-scale battery storage systems typically consist of multiple smaller units contributing to the overall power dispatch of the system. Herein, the power distribution among these units is analyzed and optimized to operate the system with increased energy efficiency. To improve the real-life storage operation, a holistic system model for battery storage systems has been developed that enables a calculation of the energy efficiency. A utility-scale Second-Life battery storage system with a capacity of 3.3 MWh/3 MW is operated and evaluated in this work. The system is in operation for the provision of primary control reserve in combination with intraday trading for controlling the battery state of charge. The simulation model is parameterized with the system data. Results show that losses in power electronics dominate. An operational strategy improving the energy efficiency through an optimized power flow distribution within the storage system is developed. The power flow distribution strategy is based on the reduction of the power electronics losses at no-load/partial-load by minimizing their in-operation time. The simulation derived power flow distribution strategy is implemented in the real-life storage system. Field-test measurements and analysis prove the functionality of the power flow distribution strategy and reveal the reduction of the energy throughput of the units by 7%, as well as a significant reduction of energy losses in the units by 24%. The cost savings for electricity over the system’s lifetime are approximated to 4.4% of its investment cost.

  5. Benchmarking of Constant Power Generation Strategies for Single-Phase Grid-Connected Photovoltaic Systems

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

    2018-01-01

    strategies based on: 1) a power control method (P-CPG), 2) a current limit method (I-CPG) and 3) the Perturb and Observe algorithm (P&O-CPG). However, the operational mode changes (e.g., from the maximum power point tracking to a CPG operation) will affect the entire system performance. Thus, a benchmarking...... of the presented CPG strategies is also conducted on a 3-kW single-phase grid-connected PV system. Comparisons reveal that either the P-CPG or I-CPG strategies can achieve fast dynamics and satisfactory steady-state performance. In contrast, the P&O-CPG algorithm is the most suitable solution in terms of high...

  6. The Role of Subscription-Based Patrol and Restitution in the Future of Liberty

    Directory of Open Access Journals (Sweden)

    Gil Guillory

    2009-02-01

    Full Text Available Market anarchists are often keen to know how we might rid ourselves of the twin evils institutionalized in the state: taxation and monopoly. A possible future history for North America is suggested, focusing upon the implications of the establishment of a subscription-based patrol and restitution business sector. We favor Rothbard over Higgs regarding crises and liberty. We favor Barnett over Rothbard regarding vertical integration of security. We examine derived demand for adjudication, mediation and related goods; and we advance the thesis that private adjudication will tend to libertarianly just decisions. We show how firms will actively build civil society, strengthening and coordinating Nisbettian intermediating institutions.

  7. Environment, renewable sources and NPPs: Strategy of Slovak Republic for the back end of nuclear power

    International Nuclear Information System (INIS)

    Timulak, J.

    2009-01-01

    The term 'back end of nuclear power' means set of activities corresponding to the final stage of utilizing the nuclear energy for peaceful purposes, or at the border of nuclear facilities with the environment. Strategy of back end of nuclear power is a basic document that specifies strategy of the Slovak Republic and all relevant subjects for the next five years in detail and for the period up to 2025 in general terms, with the prospect till the end of 21 st century. It provides proposals for implementation of the back end strategy in accordance with requirements for the health and environmental protection so that its consequences are not unacceptably transferred to next generations. The goal of the back end strategy is: - to set acceptable bases back end of nuclear power in Slovakia; - to create framework for decision-making in financial covering of the strategy activities; - to provide information on conceptual solutions of back end of nuclear power to all relevant subjects and to the public. (author)

  8. Financing strategy for Indonesian Nuclear Power Project

    International Nuclear Information System (INIS)

    Subki, I.M.; Arbie, B.; Adiwardojo; Seotrisnanto, A.Y.

    1998-01-01

    In anticipation of the introduction in the early 2000s of a nuclear power plant, the Government of Indonesia (GOI), through the National Atomic Energy Agency (BATAN) , has formulated a Bid Invitation Specification (BIS) in parallel with the completion of the NPP Feasibility Study. This BIS formulation assumed an open international tender for the first unit of the NPP with project financing as a conventional loan. The GOI's recent policy is to minimize government financial support for power development. This paper summarizes a financing strategy for the Indonesian NPP project to make the NPP economically viable, and provides a general discussion on project financing using a conventional approach, Build--Own-Operate (BOO) and a counter-purchase approach. Innovative approaches for financing are still being pursued in order to obtain an optimum solution for investors and owners, to fulfill the Indonesian government's requirements. (author)

  9. Reactive power and voltage control strategy based on dynamic and adaptive segment for DG inverter

    Science.gov (United States)

    Zhai, Jianwei; Lin, Xiaoming; Zhang, Yongjun

    2018-03-01

    The inverter of distributed generation (DG) can support reactive power to help solve the problem of out-of-limit voltage in active distribution network (ADN). Therefore, a reactive voltage control strategy based on dynamic and adaptive segment for DG inverter is put forward to actively control voltage in this paper. The proposed strategy adjusts the segmented voltage threshold of Q(U) droop curve dynamically and adaptively according to the voltage of grid-connected point and the power direction of adjacent downstream line. And then the reactive power reference of DG inverter can be got through modified Q(U) control strategy. The reactive power of inverter is controlled to trace the reference value. The proposed control strategy can not only control the local voltage of grid-connected point but also help to maintain voltage within qualified range considering the terminal voltage of distribution feeder and the reactive support for adjacent downstream DG. The scheme using the proposed strategy is compared with the scheme without the reactive support of DG inverter and the scheme using the Q(U) control strategy with constant segmented voltage threshold. The simulation results suggest that the proposed method has a significant improvement on solving the problem of out-of-limit voltage, restraining voltage variation and improving voltage quality.

  10. Prediction of VO[subscript 2]max in Children and Adolescents Using Exercise Testing and Physical Activity Questionnaire Data

    Science.gov (United States)

    Black, Nate E.; Vehrs, Pat R.; Fellingham, Gilbert W.; George, James D.; Hager, Ron

    2016-01-01

    Purpose: The purpose of this study was to evaluate the use of a treadmill walk-jog-run exercise test previously validated in adults and physical activity questionnaire data to estimate maximum oxygen consumption (VO[subscript 2]max) in boys (n = 62) and girls (n = 66) aged 12 to 17 years old. Methods: Data were collected from Physical Activity…

  11. Cyber attacks against state estimation in power systems: Vulnerability analysis and protection strategies

    Science.gov (United States)

    Liu, Xuan

    Power grid is one of the most critical infrastructures in a nation and could suffer a variety of cyber attacks. With the development of Smart Grid, false data injection attack has recently attracted wide research interest. This thesis proposes a false data attack model with incomplete network information and develops optimal attack strategies for attacking load measurements and the real-time topology of a power grid. The impacts of false data on the economic and reliable operations of power systems are quantitatively analyzed in this thesis. To mitigate the risk of cyber attacks, a distributed protection strategies are also developed. It has been shown that an attacker can design false data to avoid being detected by the control center if the network information of a power grid is known to the attacker. In practice, however, it is very hard or even impossible for an attacker to obtain all network information of a power grid. In this thesis, we propose a local load redistribution attacking model based on incomplete network information and show that an attacker only needs to obtain the network information of the local attacking region to inject false data into smart meters in the local region without being detected by the state estimator. A heuristic algorithm is developed to determine a feasible attacking region by obtaining reduced network information. This thesis investigates the impacts of false data on the operations of power systems. It has been shown that false data can be designed by an attacker to: 1) mask the real-time topology of a power grid; 2) overload a transmission line; 3) disturb the line outage detection based on PMU data. To mitigate the risk of cyber attacks, this thesis proposes a new protection strategy, which intends to mitigate the damage effects of false data injection attacks by protecting a small set of critical measurements. To further reduce the computation complexity, a mixed integer linear programming approach is also proposed to

  12. Brazil’s Soft-Power Strategy: The Political Aspirations of South–South Development Cooperation

    DEFF Research Database (Denmark)

    Bry, Sandra

    2017-01-01

    By trading upon the principles of South-South cooperation, Brazil is widely viewed as having gained a positive image worldwide. Brazil’s South-South development cooperation was one of the foreign policy instruments it used to raise this profile. However, studies of the generation of soft power...... are still lacking in the international relations literature,and where empirical research exists it focuses more on the results of soft power strategies than on how soft power is created. Therefore,this article explores how Brazil’s soft power strategy is conceptualized in Brazil’s development cooperation...... of its cooperation agency and guided it towards sectors and targets that contribute to the creation of positive outcomes. This article contributes to the debate on the state’s behavior in soft power, that is, the ‘behavior’ of the Brazilian government in the design of its cooperation agency’s activities...

  13. Strategy and system of fire protection at Guangdong Daya Bay Nuclear Power Plant

    International Nuclear Information System (INIS)

    Zhou Weihong

    1999-12-01

    The fire protection is an important safety issue of nuclear power utilities. The author depicts the strategy and management system of fire protection implemented successfully at Guangdong Daya Bay Nuclear Power Plant of China

  14. Model-based power control strategy development of a fuel cell hybrid vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Haitao, Yun [School of Automobile and Traffic, Qingdao Technological University, Qingdao Shandong 266033 (China); School of Automobile, Tongji University, ShangHai 201804 (China); Yulan, Zhao [School of Automobile and Traffic, Qingdao Technological University, Qingdao Shandong 266033 (China); Zechang, Sun; Gang, Wan [School of Automobile, Tongji University, ShangHai 201804 (China)

    2008-06-01

    An integrated procedure for math modeling and power control strategy design for a fuel cell hybrid vehicle (FCHV) is presented in this paper. Dynamic math model of the powertrain is constructed firstly, which includes four modules: fuel cell engine, DC/DC inverter, motor-driver, and power battery. Based on the mathematic model, a power control principle is designed, which uses full-states closed-loop feedback algorithm. To implement full-states feedback, a Luenberger state observer is designed to estimate open circuit voltage (OCV) of the battery, which make the control principle not sensitive to the battery SOC (state of charge) estimated error. Full-states feedback controller is then designed through analyzing step responding of the powertrain and test data. At last of the paper, the results of simulation and field test are illustrated. The results show that the power control strategy designed takes into account the performance and economy characteristics of components of the FCHV powertrain and achieves the control object excellently. (author)

  15. Dispatching strategies for coordinating environmental awareness and risk perception in wind power integrated system

    International Nuclear Information System (INIS)

    Jin, Jingliang; Zhou, Dequn; Zhou, Peng; Qian, Shuqu; Zhang, Mingming

    2016-01-01

    Wind power plays a significant role in economic and environmental operation of electric power system. Meanwhile, the variability and uncertainty characteristics of wind power generation bring technical and economical challenges for power system operation. In order to harmonize the relationship between environmental protection and risk management in power dispatching, this paper presents a stochastic dynamic economic emission dispatch model combining risk perception with environmental awareness of decision-makers by following the principle of chance-constrained programming. In this power dispatching model, the description of wind power uncertainty is derived from the probability statistic character of wind speed. Constraints-handling techniques as a heuristic strategy are embedded into non-dominated sorting genetic algorithm-II. In addition, more information is digested from the Pareto optimum solution set by cluster analysis and fuzzy set theory. The simulation results eventually demonstrate that the increase of the share of wind power output will bring higher risk, though it is beneficial for economic cost and environmental protection. Since different risk perception and environmental awareness can possibly lead to diverse non-dominated solutions, decision-makers may choose an appropriate dispatching strategy according to their specific risk perception and environmental awareness. - Highlights: • A dispatch model combining environmental awareness and risk perception is proposed. • The uncertain characteristic of available wind power is determined. • Constraints-handling techniques are embedded into genetic algorithm. • An appropriate decision-making method is designed. • Dispatching strategies can be coordinated by the proposed model and method.

  16. Promoting public transport as a subscription service: Effects of a free month travel card

    DEFF Research Database (Denmark)

    Thøgersen, John

    2009-01-01

    Newspapers, book clubs, telephone services and many other subscription services are often marketed to new customers by means of a free or substantially discounted trial period. This article evaluates this method as a means to promote commuting by public transport in a field experiment and based...... that had an effect was the free month travel card, which led to a significant increase in commuting by public transport.As expected, the effect was mediated through a change in behavioural intentions rather than a change in perceived constraints. As expected, the effect became weaker when the promotion...

  17. Strategies for sustainable development of the Polish electric power system

    International Nuclear Information System (INIS)

    Janiczek, R.

    1996-01-01

    The key features of sustainable development of the Polish electric power industry are discussed. Priorities and limitations for changes and power demand forecasts are described. Results of least-cost planning for existing power plants' modernization and generation expansion with environmental impacts are presented. The least-cost strategy is given by the optimal upgrades of older plants until year 2002 and by expansion of gas-fired units. The limited availability of gas after 2010 will lead to the construction of new coal-fired plants. For the next planning process, an integrated resource planning methodology is proposed, which includes dynamic optimization of supply and demand side options. Innovative mechanisms are shown to overcome barriers of development like long-terms contracts and decentralization of the power system planning process. (author)

  18. Optimal sizing and control strategy of isolated grid with wind power and energy storage system

    International Nuclear Information System (INIS)

    Luo, Yi; Shi, Lin; Tu, Guangyu

    2014-01-01

    Highlights: • An energy storage sizing scheme for wind powered isolated grid is developed. • A bi-level control strategy for wind-battery isolated grid is proposed. • The energy storage type selection method for Nan’ao island grid is presented. • The sizing method and the control strategy are verified based on the Nan’ao island. • The wind-battery demonstration system has great benefit for remote areas. - Abstract: Integrating renewable energy and energy storage system provides a prospective way for power supply of remote areas. Focused on the isolated grids comprising renewable energy generation and energy storage, an energy storage sizing method for taking account of the reliability requirement and a bi-level control strategy of the isolated grids are presented in this paper. Based on comparative analysis of current energy storage characteristics and practicability, Sodium–sulfur battery is recommended for power balance control in the isolated grids. The optimal size of the energy storage system is determined by genetic algorithm and sequential simulation. The annualized cost considering the compensation cost of curtailed wind power and load is minimized when the reliability requirement can be satisfied. The sizing method emphasizes the tradeoff between energy storage size and reliability of power supply. The bi-level control strategy is designed as upper level wide area power balance control in dispatch timescale and lower level battery energy storage system V/f control in real-time range for isolated operation. The mixed timescale simulation results of Nan’ao Island grid verify the effectiveness of the proposed sizing method and control strategy

  19. The development strategies of the european electric power companies

    International Nuclear Information System (INIS)

    Heddebaud, D.

    2005-01-01

    This study takes stock on the european market of the electric power and of its development perspectives. It details the strategy and the place of the main operators and shows their forces and weaknesses. It provides a comparison of the financial performances of 28 companies (growth, margins, profitability, debt and war chest). (A.L.B.)

  20. Control Strategy Based on Wavelet Transform and Neural Network for Hybrid Power System

    Directory of Open Access Journals (Sweden)

    Y. D. Song

    2013-01-01

    Full Text Available This paper deals with an energy management of a hybrid power generation system. The proposed control strategy for the energy management is based on the combination of wavelet transform and neural network arithmetic. The hybrid system in this paper consists of an emulated wind turbine generator, PV panels, DC and AC loads, lithium ion battery, and super capacitor, which are all connected on a DC bus with unified DC voltage. The control strategy is responsible for compensating the difference between the generated power from the wind and solar generators and the demanded power by the loads. Wavelet transform decomposes the power difference into smoothed component and fast fluctuated component. In consideration of battery protection, the neural network is introduced to calculate the reference power of battery. Super capacitor (SC is controlled to regulate the DC bus voltage. The model of the hybrid system is developed in detail under Matlab/Simulink software environment.

  1. 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.

  2. Bidding strategies for virtual power plants considering CHPs and intermittent renewables

    International Nuclear Information System (INIS)

    Zapata Riveros, J.; Bruninx, K.; Poncelet, K.; D’haeseleer, W.

    2015-01-01

    Highlights: • A stochastic optimization evaluates the optimal bidding strategy of a VPP. • Three different strategies were assessed: ‘static’, ‘flexible DA’ and ‘flexible RT’. • The ‘flexible RT’ attains the largest profits. It adapts the VPP output in real-time. - Abstract: Energy efficiency and renewable-energy sources (RES) are fundamental parts of the European energy policy. For this reason, efficient distributed generation technologies such as combined heat and power coupled to district heating (CHP–DH) and RES based electricity are largely promoted. Additionally, the flexibility that CHP–DH offers to the power system is seen as an option to balance the intermittent output of RES-based generation. This could be done by aggregating RES based electricity generation and CHP DH in a virtual power plant (VPP). In this framework, the present work presents a methodology to evaluate the optimal bidding strategy of a VPP composed of a CHP–DH and RES based generators. The objective is to investigate the optimal bidding strategy for a VPP that uses CHP DH to compensate for the uncertainties regarding RES-based electricity generation and market prices. The VPP operator nominates its energy to the day ahead market the day before the actual delivery (D-1). In real time, any deviation from the day-ahead schedule is settled in the imbalance market. The uncertainties are modeled using a two stage stochastic programming approach. Three different bidding strategies are studied: ‘static’, ‘flexible DA’ and ‘flexible RT’. The major difference between the studied strategies lies in the dispatch decisions. The ‘static’ strategy does not adjust the scheduled output of the CHP. Whereas, the ‘flexible DA’ and ‘flexible RT’ strategies differ from each other in terms of the information available at the moment of performing the reschedule (second stage decision). The ‘flexible DA’ reschedules the CHP output for the whole day assuming

  3. Autonomous Active and Reactive Power Distribution Strategy in Islanded Microgrids

    DEFF Research Database (Denmark)

    Wu, Dan; Tang, Fen; Guerrero, Josep M.

    2014-01-01

    This paper proposes an autonomous active and reactive power distribution strategy that can be applied directly on current control mode (CCM) inverters, being compatible as well with conventional droop-controlled voltage control mode (VCM) converters. In a microgrid, since renewable energy sources...

  4. Using the "K[subscript 5]Connected Cognition Diagram" to Analyze Teachers' Communication and Understanding of Regions in Three-Dimensional Space

    Science.gov (United States)

    Moore-Russo, Deborah; Viglietti, Janine M.

    2012-01-01

    This paper reports on a study that introduces and applies the "K[subscript 5]Connected Cognition Diagram" as a lens to explore video data showing teachers' interactions related to the partitioning of regions by axes in a three-dimensional geometric space. The study considers "semiotic bundles" (Arzarello, 2006), introduces "semiotic connections,"…

  5. 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.

  6. Assessment of Soft Power Strategies: Towards an Aggregative Analytical Model for Country-Focused Case Study Research

    Directory of Open Access Journals (Sweden)

    Patalakh Artem

    2016-10-01

    Full Text Available The paper advances a realist analytical model for case studies of national soft power policies. First, it argues that for the purposes of realist analysis, a soft power policy must be considered as a rational strategy pursued under the conditions of competition. Furthermore, it emphasises the importance of taking into account the specificities of the recipient state as well as the fact that a soft power strategy is targeted at both its elite and its public. In addition, the article substantiates the necessity to draw a clear-cut distinction between soft power sources and instruments and shows possible shortcomings that research can have should this distinction fail to be made. Finally, the paper discusses the impact of a competitor’s presence on a soft power strategy and specifies the terms under which disregarding this impact may engender a wrong conclusion.

  7. Swords into ploughshares? China's Soft Power strategy in Southeast Asia and its challenges1

    Directory of Open Access Journals (Sweden)

    Tony Tai-Ting Liu

    2014-01-01

    Full Text Available Since the 1990s, alongside China's economic growth, the international community has fostered a general anxiety towards a "China threat." In order to relieve itself from suspicion, China adopted the dual strategies of "harmonious worldview" and "good neighbor policy." The strategies led to the use of soft power in China's foreign policy. China aimed to reduce security concerns implied by the threat theory by supporting an image that caters to international peace and development. This article seeks to explain how China achieves its interests in Southeast Asia through the use of soft power. The authors address the concepts of "harmonious worldview" and "good neighbor policy" and how the twin strategies and soft power have shaped China's foreign policy in recent years. This article aims to provide insights into China's policy options in Southeast Asia in the near future.

  8. Different regulatory strategies in regulation of nuclear power projects: An Indian experience

    International Nuclear Information System (INIS)

    Khan, Sohail Ahmad

    2002-01-01

    Regulatory strategy needed for management of safety and safety culture involves careful planning and use of engineering concepts keeping in mind feasibility to implement certain safety requirements. It also requires adequate attention on working environment and mental conditions of designers, operating and maintenance staff and regulators. Different strategies followed during safety review and regulatory inspection of nuclear power projects for improving status of safety management and safety cultures have given certain results. The present paper brings out certain experience gained during regulation of Indian Nuclear Power Projects by Atomic Energy Regulatory Board of India in the area of management of safety and safety culture. (author)

  9. Predictive Power of Prospective Physical Education Teachers' Attitudes towards Educational Technologies for Their Technological Pedagogical Content Knowledge

    Science.gov (United States)

    Varol, Yaprak Kalemoglu

    2015-01-01

    The aim of the research is to determine the predictive power of prospective physical education teachers' attitudes towards educational technologies for their technological pedagogical content knowledge. In this study, a relational research model was used on a study group that consisted of 529 (M[subscript age]=21.49, SD=1.44) prospective physical…

  10. A review on the long-range strategy of nuclear power development

    International Nuclear Information System (INIS)

    An, Shigehiro; Kondo, Shunsuke; Ishida, Hiroshi.

    1979-01-01

    Nuclear power generation in Japan is proceeding steadily, such as the world's second in power generating capacity and the nation's own development of power reactors. Meanwhile, however, there are number of problems for future solution, like the establishment of nuclear fuel cycle, before nuclear energy is fully harnessed. Looking as far ahead as the 21st century, the long-range strategy of nuclear power development is reviewed: politics on uranium supply outlook, a compromise between uranium enrichment and nuclear nonproliferation, LWR technology with safety, FBR development scheme, uranium resources saving and heavy water reactor, HTGR development, a 2nd fuel reprocessing plant, high level wastes management, reactors decommissioning, research in nuclear energy development, and fostering of a nuclear power industry. (J.P.N.)

  11. Effect of Eight Weekly Aerobic Training Program on Auditory Reaction Time and MaxVO[subscript 2] in Visual Impairments

    Science.gov (United States)

    Taskin, Cengiz

    2016-01-01

    The aim of study was to examine the effect of eight weekly aerobic exercises on auditory reaction time and MaxVO[subscript 2] in visual impairments. Forty visual impairment children that have blind 3 classification from the Turkey, experimental group; (age = 15.60 ± 1.10 years; height = 164.15 ± 4.88 cm; weight = 66.60 ± 4.77 kg) for twenty…

  12. Optimal Bidding Strategies for Wind Power Producers in the Day-ahead Electricity Market

    Directory of Open Access Journals (Sweden)

    Xiaolin Liu

    2012-11-01

    Full Text Available Wind Power Producers (WPPs seek to maximize profit and minimize the imbalance costs when bidding into the day-ahead market, but uncertainties in the hourly available wind and forecasting errors make the bidding risky. This paper assumes that hourly wind power output given by the forecast follows a normal distribution, and proposes three different bidding strategies, i.e., the expected profit-maximization strategy (EPS, the chance-constrained programming-based strategy (CPS and the multi-objective bidding strategy (ECPS. Analytical solutions under the three strategies are obtained. Comparisons among the three strategies are conducted on a hypothetical wind farm which follows the Spanish market rules. Results show that bid under the EPS is highly dependent on market clearing price, imbalance prices, and also the mean value and standard deviation of wind forecast, and that bid under the CPS is largely driven by risk parameters and the mean value and standard deviation of the wind forecast. The ECPS combining both EPS and CPS tends to choose a compromise bid. Furthermore, the ECPS can effectively control the tradeoff between expected profit and target profit for WPPs operating in volatile electricity markets.

  13. Declining subscriptions to the Maliando Mutual Health Organisation in Guinea-Conakry (West Africa): what is going wrong?

    Science.gov (United States)

    Criel, Bart; Waelkens, Maria Pia

    2003-10-01

    Mutual Health Organisations (MHOs) are a type of community health insurance scheme that are being developed and promoted in sub-Saharan Africa. In 1998, an MHO was organised in a rural district of Guinea to improve access to quality health care. Households paid an annual insurance fee of about US$2 per individual. Contributions were voluntary. The benefit package included free access to all first line health care services (except for a small co-payment), free paediatric care, free emergency surgical care and free obstetric care at the district hospital. Also included were part of the cost of emergency transport to the hospital. In 1998, the MHO covered 8% of the target population, but, by 1999, the subscription rate had dropped to about 6%. In March 2000, focus groups were held with members and non-members of the scheme to find out why subscription rates were so low. The research indicated that a failure to understand the scheme does not explain these low rates. On the contrary, the great majority of research subjects, members and non-members alike, acquired a very accurate understanding of the concepts and principles underlying health insurance. They value the system's re-distributive effects, which goes beyond household, next of kin or village. The participants accurately point out the sharp differences that exist between traditional financial mechanisms and the principle of health insurance, as well as the advantages and disadvantages of both. The ease with which risk-pooling is accepted as a financial mechanism which addresses specific needs demonstrates that it is not, per se, necessary to build health insurance schemes on existing or traditional systems of mutual aid. The majority of the participants consider the individual premium of 2 US dollars to be fair. There is, however, a problem of affordability for many poor and/or large families who cannot raise enough money to pay the subscription for all household members in one go. However, the main reason for

  14. Call-related factors influencing output power from mobile phones.

    Science.gov (United States)

    Hillert, Lena; Ahlbom, Anders; Neasham, David; Feychting, Maria; Järup, Lars; Navin, Roshan; Elliott, Paul

    2006-11-01

    Mobile phone use is increasing but there is also concern for adverse health effects. Well-designed prospective studies to assess several health outcomes are required. In designing a study of mobile phone use, it is important to assess which factors need to be considered in classifying the exposure to radiofrequency fields (RF). A pilot study was performed in Sweden and in the UK 2002 to 2003 to test the feasibility of recruiting a cohort of mobile phone users from a random population sample and from mobile phone subscription lists for a prospective study. As one part of this pilot study, different factors were evaluated regarding possible influence on the output power of the phones. By local switch logging, information on calls made from predefined subscriptions or dedicated handsets were obtained and the output power of phones during calls made indoors and outdoors, in moving and stationary mode, and in rural as well in urban areas were compared. In this experiment, calls were either 1, 1.5 or 5 min long. The results showed that high mobile phone output power is more frequent in rural areas whereas the other factors (length of call, moving/stationary, indoor/outdoor) were of less importance. Urban and rural area should be considered in an exposure index for classification of the exposure to RF from mobile phones and may be assessed by first base station during mobile phone calls or, if this information is not available, possibly by using home address as a proxy.

  15. Application of MSHIM core control strategy for westinghouse AP1000 nuclear power plant

    International Nuclear Information System (INIS)

    Onoue, Masaaki; Kawanishi, Tomohiro; Carlson, William R.; Morita, Toshio

    2003-01-01

    Westinghouse has developed a new core control strategy, in which two independently moving Rod Cluster Control Assembly (RCCA) groups are utilized for core control; one group for reactivity/temperature control, the other for axial power distribution (Axial Offset) control. This control procedure eliminates the need for Chemical Shim adjustments during power maneuvers, such as load follow, and is designated MSHIM (Mechanical Shim). This core control strategy is utilized in the AP1000. In the AP1000, it is possible to perform MSHIM load follow maneuvers for up to 95% of cycle life without changing the soluble boron concentration in the moderator. This core control strategy has been evaluated, via computer simulations, to provide appropriate margins to core and fuel design limits during normal operation maneuvers (including load follow operations) and also during anticipated Condition II accident transients. The primary benefits of MSHIM as a control strategy are as follows; Power change operation can be totally automated due to the elimination of boron concentration adjustments. Full load follow capability is achievable for up to more than 95% of cycle life. Load follow operations performed solely by mechanical devices results in a significant reduction in the boron system requirements and a significant reduction in daily effluent to be processed. (author)

  16. Evaluating system reliability and targeted hardening strategies of power distribution systems subjected to hurricanes

    International Nuclear Information System (INIS)

    Salman, Abdullahi M.; Li, Yue; Stewart, Mark G.

    2015-01-01

    Over the years, power distribution systems have been vulnerable to extensive damage from hurricanes which can cause power outage resulting in millions of dollars of economic losses and restoration costs. Most of the outage is as a result of failure of distribution support structures. Over the years, various methods of strengthening distribution systems have been proposed and studied. Some of these methods, such as undergrounding of the system, have been shown to be unjustified from an economic point of view. A potential cost-effective strategy is targeted hardening of the system. This, however, requires a method of determining critical parts of a system that when strengthened, will have greater impact on reliability. This paper presents a framework for studying the effectiveness of targeted hardening strategies on power distribution systems subjected to hurricanes. The framework includes a methodology for evaluating system reliability that relates failure of poles and power delivery, determination of critical parts of a system, hurricane hazard analysis, and consideration of decay of distribution poles. The framework also incorporates cost analysis that considers economic losses due to power outage. A notional power distribution system is used to demonstrate the framework by evaluating and comparing the effectiveness of three hardening measures. - Highlight: • Risk assessment of power distribution systems subjected to hurricanes is carried out. • Framework for studying effectiveness of targeted hardening strategies is presented. • A system reliability method is proposed. • Targeted hardening is cost effective for existing systems. • Economic losses due to power outage should be considered for cost analysis.

  17. Emissions trading and firms' strategies. The case of power producers

    International Nuclear Information System (INIS)

    Rousse, O.

    2005-11-01

    This thesis deals with the impacts of a domestic emissions trading scheme on firms' strategies. As recent experiences of such programs (Acid Rain Program, RECLAIM Program, NOx Budget Program and the European Union Emissions Trading Scheme) concern mainly heat and power producers, we analyze especially strategies of these companies. In context of electricity market deregulation, our study takes two directions: uncertainty and competitive distortions. Concerning uncertainty, we are interested in portfolio management of emission permits, that is choice under uncertainty between buying, selling and banking permits. Concerning competitive distortions, we consider manipulations on the permits and/or products markets. Among others, we investigate interactions between a pollution market and the wholesale electricity market. From a general point of view, we show that a permits market, even competitive, gives to power producers more opportunities to act strategically on wholesale electricity markets. By this way, our study attempts to indicate when these market distortions are more likely to occur and to give some emissions market design instructions. (author)

  18. Decommissioning nuclear power plants. Policies, strategies and costs

    International Nuclear Information System (INIS)

    2003-01-01

    The decommissioning of nuclear power plants is a topic of increasing interest to governments and the industry as many nuclear units approach retirement. It is important in this context to assess decommissioning costs and to ensure that adequate funds are set aside to meet future financial liabilities arising after nuclear power plants are shut down. Furthermore, understanding how national policies and industrial strategies affect those costs is essential for ensuring the overall economic effectiveness of the nuclear energy sector. This report, based upon data provided by 26 countries and analysed by government and industry experts, covers a variety of reactor types and sizes. The findings on decommissioning cost elements and driving factors in their variance will be of interest to analysts and policy makers in the nuclear energy field. (author)

  19. Strategies for Power/Energy Saving in Distribution Networks

    Directory of Open Access Journals (Sweden)

    GRIGORAS, G.

    2010-05-01

    Full Text Available The power/energy losses reduction in distribution systems is an important issue during planning and operation, with important technical and economical implications. Thus, the energy losses minimization implies not only the technical improvement of the network, through its renewal with the introduction of the technological innovations in the equipment and circuit components as well as the optimal planning of the design and development of the network, but also requires the use of the methods and software tools to facilitate the operation process. The paper presents a strategy for power/energy saving which replacement of the 6 kV voltage level with 20 kV voltage level in correlation with the extent of using efficient transformers. In this line, different urban distribution networks were analyzed using fuzzy techniques.

  20. Autonomous Control Strategy of DC Microgrid for Islanding Mode Using Power Line Communication

    Directory of Open Access Journals (Sweden)

    Dong-Keun Jeong

    2018-04-01

    Full Text Available This paper proposes a DC-bus signaling (DBS method for autonomous power management in a DC microgrid, used to improve its reliability. Centralized power management systems require communication between the power sources and loads. However, the DBS method operates based on the common DC-bus voltage and does not require communication. Based on the DC-bus voltage band, the DC-bus voltage can be used to inform the status of the DC-bus in various scenarios. The DC microgrid operates independently to maintain the system stably in the DC-bus voltage band. The DC microgrid can be divided into a grid-connected mode and an islanding mode. This paper proposes a control strategy based on power management of various independent components in islanding mode. In addition, the autonomous control method for switching the converter’s operation between grid-connected mode and islanding mode is proposed. A DC microgrid test bed consisting of a grid-connected AC/DC converter, a bidirectional DC/DC converter, a renewable energy simulator, DC home appliances and a DC-bus protector is used to test the proposed control strategy. The proposed autonomous control strategy is experimentally verified using the DC microgrid test bed.

  1. Decommissioning of nuclear power plants: policies, strategies and costs

    International Nuclear Information System (INIS)

    Lund, I.

    2004-01-01

    As many nuclear power plants will reach the end of their lifetime during the next 20 years or so, decommissioning is an increasingly important topic for governments, regulators and industries. From a governmental viewpoint, particularly in a deregulated market, one essential aspect is to ensure that money for the decommissioning of nuclear installations will be available at the time it is needed, and that no 'stranded' liabilities will be left to be financed by the taxpayers rather than by the electricity consumers. For this reason, there is governmental interest in understanding decommissioning costs, and in periodically reviewing decommissioning cost estimates from nuclear installation owners. Robust cost estimates are key elements in designing and implementing a coherent and comprehensive national decommissioning policy including the legal and regulatory bases for the collection, saving and use of decommissioning funds. From the industry viewpoint, it is essential to assess and monitor decommissioning costs in order to develop a coherent decommissioning strategy that reflects national policy and assures worker and public safety, whilst also being cost effective. For these reasons, nuclear power plant owners are interested in understanding decommissioning costs as best as possible and in identifying major cost drivers, whether they be policy, strategy or 'physical' in nature. National policy considerations will guide the development of national regulations that are relevant for decommissioning activities. Following these policies and regulations, industrial managers responsible for decommissioning activities will develop strategies which best suit their needs, while appropriately meeting all government requirements. Decommissioning costs will be determined by technical and economic conditions, as well as by the strategy adopted. Against this backdrop, the study analyses the relationships among decommissioning policy as developed by governments, decommissioning

  2. Experimental Determination of pK[subscript a] Values and Metal Binding for Biomolecular Compounds Using [superscript 31]P NMR Spectroscopy

    Science.gov (United States)

    Swartz, Mason A.; Tubergen, Philip J.; Tatko, Chad D.; Baker, Rachael A.

    2018-01-01

    This lab experiment uses [superscript 31]P NMR spectroscopy of biomolecules to determine pK[subscript a] values and the binding energies of metal/biomolecule complexes. Solutions of adenosine nucleotides are prepared, and a series of [superscript 31]P NMR spectra are collected as a function of pH and in the absence and presence of magnesium or…

  3. Low power offloading strategy for femto-cloud mobile network

    Directory of Open Access Journals (Sweden)

    Anwesha Mukherjee

    2016-03-01

    Full Text Available Nowadays offloading is a popular method of mobile cloud computing where the required computation takes place remotely inside the cloud. But whether to process an application inside the mobile device or to the cloud is a challenging issue because communication with the cloud involves latency and power consumption. This paper has proposed a method of decision making regarding whether to offload or not-to-offload an application to the cloud. According to the proposed strategy, application is offloaded only if it results in lower power consumption than local execution within the mobile device itself. If this condition is satisfied, computation time and deadline of the job are considered as the basic parameters to decide whether to offload or not. Experimental results demonstrate that the proposed offloading algorithm reduces the power consumption to approximately 3–32%. To achieve power-efficiency and security both, femto-cloud architecture is used in the proposed work. In this case offloading from the mobile device to the cloud takes place through the low power and secure femtocell base station. Simulation results present that using femto-cloud architecture 70–83% and 52–66% power savings are achieved than using macrocell and microcell base stations respectively while offloading an application to the cloud.

  4. POWER STRATEGY OF THE AGRICULTURE DEVELOPMENT IN THE CONDITIONS OF CRISIS

    Directory of Open Access Journals (Sweden)

    Burdo O.G.

    2009-04-01

    Full Text Available Questions of the development of energetics in the world are examined. Specifics of the energy supply in agriculture are discussed and the basics of energy policy and strategy in crisis conditions are formulated. The methodology of power monitoring and basics of economy of power management are shown. Priorities at forma-tion of stages of projects implementation are proved. Ways of energy efficiency programs creation using partial projects self–financing mechanisms are shown.

  5. Power and Energy Management Strategy for Solid State Transformer Interfaced DC Microgrid

    Science.gov (United States)

    Yu, Xunwei

    As a result of more and more applications of renewable energy into our ordinary life, how to construct a microgrid (MG) based on the distributed renewable energy resources and energy storages, and then to supply a reliable and flexible power to the conventional power system are the hottest topics nowadays. Comparing to the AC microgrid (AC MG), DC microgrid (DC MG) gets more attentions, because it has its own advantages, such as high efficiency, easy to integrate the DC energy sources and energy storages, and so on. Furthermore, the interaction between DC MG system and the distribution system is also an important and practical issue. In Future Renewable Electric Energy Delivery and Management Systems Center (FREEDM), the Solid State Transformer (SST) is built, which can transform the distribution system to the low AC and DC system directly (usually home application level). Thus, the SST gives a new promising solution for low voltage level MG to interface the distribution level system instead of the traditional transformer. So a SST interfaced DC MG is proposed. However, it also brings new challenges in the design and control fields for this system because the system gets more complicated, which includes distributed energy sources and storages, load, and SST. The purpose of this dissertation is to design a reliable and flexible SST interfaced DC MG based on the renewable energy sources and energy storages, which can operate in islanding mode and SST-enabled mode. Dual Half Bridge (DHB) is selected as the topology for DC/DC converter in DC MG. The DHB operation procedure and average model are analyzed, which is the basis for the system modeling, control and operation. Furthermore, two novel power and energy management strategies are proposed. The first one is a distributed energy management strategy for the DC MG operating in the SST-enabled mode. In this method, the system is not only in distributed control to increase the system reliability, but the power sharing

  6. Overall strategy of Creys Malville power station dismantling

    International Nuclear Information System (INIS)

    Alphonse, P.

    2002-01-01

    The power station was stopped by a government decision following the elections in 1997. This shutdown was then made official by a letter dated April 1998 and the decree of December 1998. This was a non-technical shutdown and as such had not been envisaged; there has been no early warning. Current dismantling strategy: The studies leading to shutdown and then dismantling were engaged in 1998 based on a scenario with a status corresponding to IAEA level 2 until 2046. In 2001, EDF management made the decision to dismantle all the first generation power stations and Creys Malville between now and 2025. It should be noted that the presence of strongly irradiated stellite in the Creys Malville reactor would still require remote systems for working in the reactor block after 2046. The sequence of operations dictated by the dismantling strategy is as follows: eliminate the risks as soon as possible and in particular the risk related to the sodium, 3300 tonnes of which is kept in liquid form in the reactor vessel; dismantle the most active parts which are too radioactive to be sent to the existing or planned storage centres. This may lead to on-site storage to allow decay to occur before sending to a storage centre; planning of the work interventions in order to limit the costs

  7. Alterations in CNS Activity Induced by Botulinum Toxin Treatment in Spasmodic Dysphonia: An H[subscript 2][superscript 15]O PET Study

    Science.gov (United States)

    Ali, S. Omar; Thomassen, Michael; Schulz, Geralyn M.; Hosey, Lara A.; Varga, Mary; Ludlow, Christy L.; Braun, Allen R.

    2006-01-01

    Speech-related changes in regional cerebral blood flow (rCBF) were measured using H[subscript 2][superscript 15]O positron-emission tomography in 9 adults with adductor spasmodic dysphonia (ADSD) before and after botulinum toxin (BTX) injection and 10 age- and gender-matched volunteers without neurological disorders. Scans were acquired at rest…

  8. Evaluation of SO2 compliance strategies at Virginia Power

    International Nuclear Information System (INIS)

    Presley, J.V.; Tomlinson, M.; Ulmer, R.H.

    1992-01-01

    This paper will address the process undertaken by Virginia Power to assess SO 2 control strategies available for complying with the Revised Clean Air Act. In April 1990, in anticipation of the passage of an amended Clean Air Act, Virginia Power assembled a task force of personnel from a wide cross section of the company. This task force was given the responsibility of providing an assessment of the requirements of the new legislation, evaluating compliance alternatives and providing recommendations for implementation of the least cost alternative. Twenty-four potential SO 2 compliance options were identified for evaluation for Phase I. These options included various levels of coal switching, gas co-firing and scrubbing. Each option was evaluated and compared to a base case which assumed no SO 2 control. As a result of our evaluations, the lowest cost and least risk approach to Phase I SO 2 compliance for Virginia Power appears to be to construct a scrubber for one unit (550 MW g ) at our Mt. Storm Power Station

  9. Soft power as part of China's strategy for national image cultivation

    DEFF Research Database (Denmark)

    Overgaard, Signe

    In recent years soft power has become a key issue at the highest political level in China, focusing especially on cultural soft power. This is reflected in important political documents, such as five year plans, plenum meeting summaries, as well as speeches by Hu Jintao and other politicians...... at the highest level. This interest in soft power is generally seen as part of an important foreign policy shift, and the huge amounts of money spent by the government on cultural diplomacy testify to the importance attached to it. Understanding what might be the goal of China’s soft power strategy is however...... difficult. The question can be analysed from various perspectives focusing on the use of power, the peaceful development discourse, or national image cultivation, and finding a straight forward answer is therefore difficult. If we go deeper and see the soft power discourse in the context of the worries...

  10. Some problems of recent 'All Japan' strategy for nuclear power exports. Identification of its problems and a proposal for improvement based on international development strategies of the major three categories of businesses constituting nuclear power industry

    International Nuclear Information System (INIS)

    Tanabe, Tomoyuki

    2011-01-01

    In Japan, 'All Japan' strategy for nuclear power exports, which arranges engineering companies and electric utilities to sell nuclear power plants providing engineering, procurement, construction and operation abroad, with governmental support of expanded trade insurance, is strongly promoted today as a part of Japan's national growth strategy. However, 'All Japan' strategy generates some problems because the strategy does not consider difference of business strategies concerning international development of each enterprise. This report identifies problems of 'All Japan' strategy based on environmental scanning of major three categories of businesses, which are big nuclear technology companies, vendors and electric utilities constituting nuclear power industry. And this report proposes the way to improve the strategy as follows to resolve those problems. 1) It is necessary to assess the risk of the project that is to be undertaken by 'All Japan' approach carefully. 2) Governmental support for vendors is also needed because the vendors are source of strength of international development of the nuclear industry in Japan. 3) Where the cooperation among the electric utilities is necessary, imposing the risk burden on the utilities should be avoided. 4) It is necessary for government to take measures about 'Weakness' and 'Threat' that each category of business commonly faces. (author)

  11. Microgrid Control Strategy Utlizing Thermal Energy Storage With Renewable Solar And Wind Power Generation

    Science.gov (United States)

    2016-06-01

    iii Approved for public release; distribution is unlimited MICROGRID CONTROL STRATEGY UTLIZING THERMAL ENERGY STORAGE WITH RENEWABLE SOLAR AND WIND... control tracks increasing power generation in the morning. The batteries require a large amount of electrical power to charge every morning, as charge ...is 37 lost throughout the night. This causes the solar panels to output their maximum power generation. The MPPT control records when power

  12. Review of Active and Reactive Power Sharing Strategies in Hierarchical Controlled Microgrids

    DEFF Research Database (Denmark)

    Han, Yang; Li, Hong; Shen, Pan

    2017-01-01

    Microgrids consist of multiple parallel-connected distributed generation (DG) units with coordinated control strategies, which are able to operate in both grid-connected and islanded mode. Microgrids are attracting more and more attention since they can alleviate the stress of main transmission...... systems, reduce feeder losses, and improve system power quality. When the islanded microgrids are concerned, it is important to maintain system stability and achieve load power sharing among the multiple parallel-connected DG units. However, the poor active and reactive power sharing problems due...... in this paper for active power sharing. Moreover, nonlinear and unbalanced loads could further affect the reactive power sharing when regulating the active power, and it is difficult to share the reactive power accurately only by using the enhanced virtual impedance method. Therefore, the hierarchical control...

  13. Design of Energy Storage Control Strategy to Improve the PV System Power Quality

    DEFF Research Database (Denmark)

    Lei, Mingyu; Yang, Zilong; Wang, Yibo

    2016-01-01

    Random fluctuation of PV power is becoming a more and more serious problem affecting the power quality and stability of grid as the PV penetration keeps increasing recent years. Aiming at this problem, this paper proposed a control strategy of energy storage system based on Model Predictive Contr...

  14. Impact of DC link control strategies on the power-flow convergence of integrated AC–DC systems

    Directory of Open Access Journals (Sweden)

    Shagufta Khan

    2016-03-01

    Full Text Available For the power-flow solution of integrated AC–DC systems, five quantities are required to be solved per converter, against three independent equations available. These three equations consist of two basic converter equations and one DC network equation, corresponding to each converter. Thus, for solution, two additional equations are required. These two equations are derived from the control specifications adopted for the DC link. Depending on the application, several combinations of valid control specifications are possible. A set of valid control specifications constitutes a control strategy. It is observed that the control strategy adopted for the DC link strongly affects the power-flow convergence of integrated AC–DC systems. This paper investigates how different control strategies affect the power flow convergence of integrated AC–DC systems. Sequential method is used to solve the DC variables in the Newton Raphson (NR power flow model. Seven typical control strategies have been taken into consideration. This is validated by numerous case studies carried out with multiple DC links incorporated in the IEEE 118-bus and 300-bus test systems.

  15. Energy management strategies for combined heat and electric power micro-grid

    Directory of Open Access Journals (Sweden)

    Barbarić Marina

    2016-01-01

    Full Text Available The increasing energy production from variable renewable energy sources such as wind and solar has resulted in several challenges related to the system reliability and efficiency. In order to ensure the supply-demand balance under the conditions of higher variability the micro-grid concept of active distribution networks arising as a promising one. However, to achieve all the potential benefits that micro-gird concept offer, it is important to determine optimal operating strategies for micro-grids. The present paper compares three energy management strategies, aimed at ensuring economical micro-grid operation, to find a compromise between the complexity of strategy and its efficiency. The first strategy combines optimization technique and an additional rule while the second strategy is based on the pure optimization approach. The third strategy uses model based predictive control scheme to take into account uncertainties in renewable generation and energy consumption. In order to compare the strategies with respect to cost effectiveness, a residential micro-grid comprising photovoltaic modules, thermal energy storage system, thermal loads, electrical loads as well as combined heat and power plant, is considered.

  16. Pelvic movement strategies and leg extension power in patients with end-stage medial compartment knee osteoarthritis

    DEFF Research Database (Denmark)

    Kierkegaard, Signe; Jørgensen, Peter Bo; Dalgas, Ulrik

    2015-01-01

    advancing functional tasks, and how these strategies are associated with leg extension power. The aim of the study was to investigate pelvic movement strategies and leg extension power in patients with end-stage medial compartment knee osteoarthritis compared with controls. MATERIALS AND METHODS: 57...... patients (mean age 65.6 years) scheduled for medial uni-compartmental knee arthroplasty, and 29 age and gender matched controls were included in this cross-sectional study. Leg extension power was tested with the Nottingham Leg Extension Power-Rig. Pelvic range of motion was derived from an inertia......-based measurement unit placed over the sacrum bone during walking, stair climbing and stepping. RESULTS: Patients had lower leg extension power than controls (20-39 %, P

  17. Design of a nonlinear backstepping control strategy of grid interconnected wind power system based PMSG

    Science.gov (United States)

    Errami, Y.; Obbadi, A.; Sahnoun, S.; Benhmida, M.; Ouassaid, M.; Maaroufi, M.

    2016-07-01

    This paper presents nonlinear backstepping control for Wind Power Generation System (WPGS) based Permanent Magnet Synchronous Generator (PMSG) and connected to utility grid. The block diagram of the WPGS with PMSG and the grid side back-to-back converter is established with the dq frame of axes. This control scheme emphasises the regulation of the dc-link voltage and the control of the power factor at changing wind speed. Besides, in the proposed control strategy of WPGS, Maximum Power Point Tracking (MPPT) technique and pitch control are provided. The stability of the regulators is assured by employing Lyapunov analysis. The proposed control strategy for the system has been validated by MATLAB simulations under varying wind velocity and the grid fault condition. In addition, a comparison of simulation results based on the proposed Backstepping strategy and conventional Vector Control is provided.

  18. Control strategies to optimise power output in heave buoy energy convertors

    International Nuclear Information System (INIS)

    Abu Zarim, M A U A; Sharip, R M

    2013-01-01

    Wave energy converter (WEC) designs are always discussed in order to obtain an optimum design to generate the power from the wave. Output power from wave energy converter can be improved by controlling the oscillation in order to acquire the interaction between the WEC and the incident wave.The purpose of this research is to study the heave buoys in the interest to generate an optimum power output by optimising the phase control and amplitude in order to maximise the active power. In line with the real aims of this study which investigate the theory and function and hence optimise the power generation of heave buoys as renewable energy sources, the condition that influence the heave buoy must be understand in which to propose the control strategies that can be use to control parameters to obtain optimum power output. However, this research is in an early stage, and further analysis and technical development is require

  19. Implementing the strategy of multileveled PI activities to promote rapid nuclear power development

    International Nuclear Information System (INIS)

    Chen Gang

    2005-01-01

    The first two decades of the 21st century is the golden time for nuclear power development in China. According to the nuclear power development program laid down by the State Development and Reform Commission, nearly 30 units of 1000MW will be built in the next 15 years, so as to meet fastgrowing energy demand, to optimize energy mix and to alleviate environmental pollution. Under such a new situation, based on the public information practice and experience during the construction and operation of Qinshan Nuclear Power Complex where the first commercial NPP originated in the Mainland of China, this paper emphasizes on the necessity of establishment of an active and open strategy of multileveled nuclear energy public information activities and implementation of the strategy with adoption of various forms of nuclear energy popularization means, including seminars, contests, exhibitions, site tour to nuclear power plants, reports by mass media, hosting questions-answering dialogue by experts via Internet, TV and radio programs, newspapers and journals , etc.. Thus through the nuclear energy public information activity the recognition and confidence of the public, especially the local community and the public in vicinity of new nuclear power sites on the nuclear energy can be enhanced, and the nuclear power program can gain their support. Furthermore, the fine social environment for nuclear power development can be fostered. (authors)

  20. Strategies for the co-operation between power generation facilities and power sales organisations in the European electricity market

    International Nuclear Information System (INIS)

    Bammert, U.

    2003-01-01

    This article discusses how the public utilities in Hannover, Germany, have developed a strategy for the operation of their power generation facilities and power distribution network as independent yet co-operating units. Three models that were examined are described: 'free-sailing', where generation and distribution were kept completely independent, the 'wedding' model, where they were closely tied together and 'Enercity', a mixture of both models. The various rules necessary and the degrees of freedom needed to implement the 'Enercity' model are discussed, as are the advantages it offers to both the power generation and the sales units

  1. The GABA[subscript A] Receptor Agonist Muscimol Induces an Age- and Region-Dependent Form of Long-Term Depression in the Mouse Striatum

    Science.gov (United States)

    Zhang, Xiaoqun; Yao, Ning; Chergui, Karima

    2016-01-01

    Several forms of long-term depression (LTD) of glutamatergic synaptic transmission have been identified in the dorsal striatum and in the nucleus accumbens (NAc). Such experience-dependent synaptic plasticity might play important roles in reward-related learning. The GABA[subscript A] receptor agonist muscimol was recently found to trigger a…

  2. Students’ goal orientations and learning strategies in a powerful learning environment : a case study

    NARCIS (Netherlands)

    Koopman, M.; Bakx, A.W.E.A.; Beijaard, D.

    2014-01-01

    In Dutch secondary education, experiments with powerful social constructivist learning environments are conducted that aim to appeal to students’ intrinsic goal orientations, use of deep cognitive learning strategies, and self-direction of meta-cognitive learning strategies. The aim of this study is

  3. Power plant technology 2014. Strategies, systems engineering and operation; Kraftwerkstechnik 2014. Strategien, Anlagentechnik und Betrieb

    Energy Technology Data Exchange (ETDEWEB)

    Beckmann, Michael; Hurtado, Antonio

    2014-07-01

    The book on power plant technology 2014 (strategies, systems engineering and operation) covers the following issues: Climate, politics and economy; wind power; fossil-fuel power plants, flexible power plants - plant operation, flexible power plants- materials, materials for energy technology, fuel feed and incineration, modeling of the water-vapor-circuit, corrosion, deposits and cleaning, vapor turbines, GUD power plants, fluidized bed combustion, energetic biomass use, combined heat and power generation and decentralized units, storage facilities, emissions - mitigation and measuring techniques.

  4. Regenerative Braking Compensatory Control Strategy Considering CVT Power Loss for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Yang Yang

    2018-02-01

    Full Text Available Hybrid electric vehicles (HEV equipped with continuously variable transmission (CVT adjust the motor operating point continuously to achieve the optimal motor operating efficiency during regenerative braking. Traditional control strategies consider the CVT efficiency as constant, while the CVT efficiency varies in different operating conditions. In order to reflect the transmission efficiency more accurately during regenerative braking, the CVT theoretical torque loss model is firstly established which then leads to the battery–front motor–CVT joint operating efficiency model. The joint operating efficiency model indicates that the system efficiency is influenced by input speed, input torque, CVT speed ratio, and battery SOC (state of charge. The compensatory strategy for the front motor barking force is proposed to make full use of its braking power and the CVT speed ratio control strategy is modified to maintain the optimal operating efficiency of the system. The simulations are performed under three typical braking conditions and UDDS, NYCC, US06 respectively, the results show that the modified control strategy increases the front motor braking power and improves the system operating efficiency.

  5. A new strategy of axial power distribution control based on three axial offsets concept

    International Nuclear Information System (INIS)

    Shimazu, Yoichiro

    2009-01-01

    We have proposed a very simple control procedure for axial xenon oscillation control based on a characteristic trajectory. The trajectory is drawn by three offsets of power distributions, namely, AOp, AOi and AOx. They are defined as the offset of axial power distribution, the offset of the power distribution under which the current iodine distribution is obtained as the equilibrium and that for xenon distribution, respectively. When these offsets are plotted on X-Y plane for (AOp-AOx, AOi-AOx) the trajectory draws a quite characteristic ellipse (or an elliptic spiral). On the other hands, Constant Axial Offset Control (CAOC) procedure is adopted as axial power distribution control strategy during both base load and load following operations in domestic PWRs. In the previous paper, we have presented an innovative procedure of axial power distribution control during load following in PWRs based on this trajectory such that the AOp-AOx is to be controlled to zero when the value deviates the pre-determined limiting values. In this paper we propose a modified control strategy to get more stability of axial power distributions. In this strategy, we control the trajectory to be close to the major axis of the ellipse when the power distribution reaches the limiting values. In other words, the plot is not controlled only to reduce AOp-AOx but also AOi-AOx is taken into account at the same time. It is known that when the plot is controlled to the major axis, it means that the point gives the peak position of axial xenon oscillation. Therefore xenon oscillation will not increase its amplitude any more. Thus more stable axial power distribution control is attained. This kind of design concept is quite important especially for the future PWRs with elongated fuel length and longer core life. Because in a longer effective core and also the longer core life, it has been known that the stability of axial xenon oscillation becomes more unstable. In this paper, some simulation

  6. Utility-Marketer Partnerships. An Effective Strategy for Marketing Green Power?

    Energy Technology Data Exchange (ETDEWEB)

    Bird, L. A. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Brown, E. S. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2006-04-01

    This paper explores whether partnerships between utilities and independent marketers are an effective strategy for marketing green power. We present case studies of voluntary and mandatory partnerships covering green power program design and implementation in both regulated and restructured electricity markets. We also include perspectives (based on interviews) from utilities, marketers, and regulators involved in developing and implementing these partnerships. From these case studies and interviews, we describe lessons learned about developing effective partnerships, including such issues as respective roles in marketing and administration, product branding, and contract and incentive structures. Based on experience to date, strategic partnerships between utilities and marketers can be an effective approach to marketing green power. Partnerships leverage the sales and resource procurement experience of marketers and the utility’s reputation and access to customers. Further, partnerships can create greater incentives for success because marketers have a vested financial interest in maximizing customer participation and green power sales.

  7. Utility-Marketing Partnerships: An Effective Strategy for Marketing Green Power?

    Energy Technology Data Exchange (ETDEWEB)

    Bird, L. A.; Brown, E. S.

    2006-04-01

    This paper explores whether partnerships between utilities and independent marketers are an effective strategy for marketing green power. We present case studies of voluntary and mandatory partnerships covering green power program design and implementation in both regulated and restructured electricity markets. We also include perspectives (based on interviews) from utilities, marketers, and regulators involved in developing and implementing these partnerships. From these case studies and interviews, we describe lessons learned about developing effective partnerships, including such issues as respective roles in marketing and administration, product branding, and contract and incentive structures. Based on experience to date, strategic partnerships between utilities and marketers can be an effective approach to marketing green power. Partnerships leverage the sales and resource procurement experience of marketers and the utility?s reputation and access to customers. Further, partnerships can create greater incentives for success because marketers have a vested financial interest in maximizing customer participation and green power sales.

  8. Nuclear power enterprise tax planning strategy in the background of reform

    International Nuclear Information System (INIS)

    Wu Yimin

    2012-01-01

    The success of tax planning can be converted into enterprise's productivity, tax planning strategy can maximize the desired effects and bring out its full play to tax planning. Taking new round of tax reform in 12th five-year-plan and the reformation of professional groups as the background, the author detailedly conceived a frame of corporate tax planning strategy for nuclear power enterprises of China National Nuclear Corporation at the forefront of reformation from an all-round comprehensive view and multi-angle stand. (author)

  9. A Single-Degree-of-Freedom Energy Optimization Strategy for Power-Split Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Chaoying Xia

    2017-07-01

    Full Text Available This paper presents a single-degree-of-freedom energy optimization strategy to solve the energy management problem existing in power-split hybrid electric vehicles (HEVs. The proposed strategy is based on a quadratic performance index, which is innovatively designed to simultaneously restrict the fluctuation of battery state of charge (SOC and reduce fuel consumption. An extended quadratic optimal control problem is formulated by approximating the fuel consumption rate as a quadratic polynomial of engine power. The approximated optimal control law is obtained by utilizing the solution properties of the Riccati equation and adjoint equation. It is easy to implement in real-time and the engineering significance is explained in details. In order to validate the effectiveness of the proposed strategy, the forward-facing vehicle simulation model is established based on the ADVISOR software (Version 2002, National Renewable Energy Laboratory, Golden, CO, USA. The simulation results show that there is only a little fuel consumption difference between the proposed strategy and the Pontryagin’s minimum principle (PMP-based global optimal strategy, and the proposed strategy also exhibits good adaptability under different initial battery SOC, cargo mass and road slope conditions.

  10. A Power System Optimal Dispatch Strategy Considering the Flow of Carbon Emissions and Large Consumers

    Directory of Open Access Journals (Sweden)

    Jun Yang

    2015-08-01

    Full Text Available The carbon emissions trading market and direct power purchases by large consumers are two promising directions of power system development. To trace the carbon emission flow in the power grid, the theory of carbon emission flow is improved by allocating power loss to the load side. Based on the improved carbon emission flow theory, an optimal dispatch model is proposed to optimize the cost of both large consumers and the power grid, which will benefit from the carbon emissions trading market. Moreover, to better simulate reality, the direct purchase of power by large consumers is also considered in this paper. The OPF (optimal power flow method is applied to solve the problem. To evaluate our proposed optimal dispatch strategy, an IEEE 30-bus system is used to test the performance. The effects of the price of carbon emissions and the price of electricity from normal generators and low-carbon generators with regards to the optimal dispatch are analyzed. The simulation results indicate that the proposed strategy can significantly reduce both the operation cost of the power grid and the power utilization cost of large consumers.

  11. Using the noninformative families in family-based association tests : A powerful new testing strategy

    NARCIS (Netherlands)

    Lange, C; DeMeo, D; Silverman, EK; Weiss, ST; Laird, NM

    2003-01-01

    For genetic association studies with multiple phenotypes, we propose a new strategy for multiple testing with family-based association tests (FBATs). The strategy increases the power by both using all available family data and reducing the number of hypotheses tested while being robust against

  12. Diversity Strategies for Nuclear Power Plant Instrumentation and Control Systems

    International Nuclear Information System (INIS)

    Wood, Richard Thomas; Belles, Randy; Cetiner, Mustafa Sacit; Holcomb, David Eugene; Korsah, Kofi; Loebl, Andy; Mays, Gary T.; Muhlheim, Michael David; Mullens, James Allen; Poore, Willis P. III; Qualls, A.L.; Wilson, Thomas L.; Waterman, Michael E.

    2010-01-01

    This report presents the technical basis for establishing acceptable mitigating strategies that resolve diversity and defense-in-depth (D3) assessment findings and conform to U.S. Nuclear Regulatory Commission (NRC) requirements. The research approach employed to establish appropriate diversity strategies involves investigation of available documentation on D3 methods and experience from nuclear power and nonnuclear industries, capture of expert knowledge and lessons learned, determination of best practices, and assessment of the nature of common-cause failures (CCFs) and compensating diversity attributes. The research described in this report does not provide guidance on how to determine the need for diversity in a safety system to mitigate the consequences of potential CCFs. Rather, the scope of this report provides guidance to the staff and nuclear industry after a licensee or applicant has performed a D3 assessment per NUREG/CR-6303 and determined that diversity in a safety system is needed for mitigating the consequences of potential CCFs identified in the evaluation of the safety system design features. Succinctly, the purpose of the research described in this report was to answer the question, 'If diversity is required in a safety system to mitigate the consequences of potential CCFs, how much diversity is enough?' The principal results of this research effort have identified and developed diversity strategies, which consist of combinations of diversity attributes and their associated criteria. Technology, which corresponds to design diversity, is chosen as the principal system characteristic by which diversity criteria are grouped to form strategies. The rationale for this classification framework involves consideration of the profound impact that technology-focused design diversity provides. Consequently, the diversity usage classification scheme involves three families of strategies: (1) different technologies, (2) different approaches within the same

  13. Diversity Strategies for Nuclear Power Plant Instrumentation and Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Richard Thomas [ORNL; Belles, Randy [ORNL; Cetiner, Mustafa Sacit [ORNL; Holcomb, David Eugene [ORNL; Korsah, Kofi [ORNL; Loebl, Andy [ORNL; Mays, Gary T [ORNL; Muhlheim, Michael David [ORNL; Mullens, James Allen [ORNL; Poore III, Willis P [ORNL; Qualls, A L [ORNL; Wilson, Thomas L [ORNL; Waterman, Michael E. [U.S. Nuclear Regulatory Commission

    2010-02-01

    This report presents the technical basis for establishing acceptable mitigating strategies that resolve diversity and defense-in-depth (D3) assessment findings and conform to U.S. Nuclear Regulatory Commission (NRC) requirements. The research approach employed to establish appropriate diversity strategies involves investigation of available documentation on D3 methods and experience from nuclear power and nonnuclear industries, capture of expert knowledge and lessons learned, determination of best practices, and assessment of the nature of common-cause failures (CCFs) and compensating diversity attributes. The research described in this report does not provide guidance on how to determine the need for diversity in a safety system to mitigate the consequences of potential CCFs. Rather, the scope of this report provides guidance to the staff and nuclear industry after a licensee or applicant has performed a D3 assessment per NUREG/CR-6303 and determined that diversity in a safety system is needed for mitigating the consequences of potential CCFs identified in the evaluation of the safety system design features. Succinctly, the purpose of the research described in this report was to answer the question, 'If diversity is required in a safety system to mitigate the consequences of potential CCFs, how much diversity is enough?' The principal results of this research effort have identified and developed diversity strategies, which consist of combinations of diversity attributes and their associated criteria. Technology, which corresponds to design diversity, is chosen as the principal system characteristic by which diversity criteria are grouped to form strategies. The rationale for this classification framework involves consideration of the profound impact that technology-focused design diversity provides. Consequently, the diversity usage classification scheme involves three families of strategies: (1) different technologies, (2) different approaches within

  14. A Wireless Power Sharing Control Strategy for Hybrid Energy Storage Systems in DC Microgrids

    DEFF Research Database (Denmark)

    Yang, Jie; Jin, Xinmin; Wu, Xuezhi

    2017-01-01

    In order to compensate multiple time scales power fluctuation resulted from distributed energy resources and loads, hybrid energy storage systems are employed as the buffer unit in DC microgrid. In this paper, a wireless hierarchical control strategy is proposed to realize power sharing between...

  15. Prospects and strategy for large scale utility applications of photovoltaic power systems

    International Nuclear Information System (INIS)

    Cole, A.; Vigotti, R.; Lysen, E.

    1995-01-01

    The paper reviews the status and prospects of photovoltaic power systems and the R and D trends (silicon performances, thin films, balance of systems components), and describes the market diffusion strategy for the application of PV systems: at the short and medium term level, isolated systems for rural electricity supply in IEA member countries and decentralized energy supply (remote users and village power) in developing countries; at the medium and long term level, decentralized building integration in urban and rural areas, power stations for peak power and local grid support. The objectives of the IEA collaboration programme launched among 18 industrialized countries are summarized, with particular reference to technology transfer to developing countries. 4 figs

  16. Energy management strategy for solar-powered high-altitude long-endurance aircraft

    International Nuclear Information System (INIS)

    Gao, Xian-Zhong; Hou, Zhong-Xi; Guo, Zheng; Liu, Jian-Xia; Chen, Xiao-Qian

    2013-01-01

    Highlights: ► A new Energy Management Strategy (EMS) for high-altitude solar-powered aircraft is purposed. ► The simulations show that the aircraft can always keep the altitude above 16 km with the proposed EMS. ► The proposed EMS is capable to alleviate the power consumed for aircraft during night. ► The main technologies to improve the flight performance of aircraft are analyzed. - Abstract: Development of solar-powered High-Altitude Long-Endurance (HALE) aircraft has a great impact on both military and civil aviation industries since its features in high-altitude and energy source can be considered inexhaustible. Owing to the development constraints of rechargeable batteries, the solar-powered HALE aircraft must take amount of rechargeable batteries to fulfill the energy requirement in night, which greatly limits the operation altitude of aircraft. In order to solve this problem, a new Energy Management Strategy (EMS) is proposed based on the idea that the solar energy can be partly stored in gravitational potential in daytime. The flight path of HALE aircraft is divided into three stages. During the stage 1, the solar energy is stored in both lithium–sulfur battery and gravitational potential. The gravitational potential is released in stage 2 by gravitational gliding and the required power in stage 3 is supplied by lithium–sulfur battery. Correspondingly, the EMS is designed for each stage. The simulation results show that the aircraft can always keep the altitude above 16 km with the proposed EMS, and the power consumed during night can be also alleviated. Comparing with the current EMS, about 23.5% energy is remained in batteries with the proposed EMS during one day–night cycle. The sensitivities of the improvement of crucial technologies to the performance of aircraft are also analyzed. The results show that the enhancement of control and structural system, lithium–sulfur battery, and solar cell are ranked in descending order for the

  17. Carbon Emissions Trading and Combined Heat and Power Strategies: Unintended Consequences

    Science.gov (United States)

    Tysseling, John C.; Vosevich, Mary; Boersma, Benjamin R.; Zumwalt, Jefferey A.

    2009-01-01

    Facility professionals continuously search for projects that reduce energy consumption and operating costs so as to directly benefit their bottom line. Many institutions nationwide have contemplated or made investments in combined heat and power (CHP) projects as a life-cycle strategy to minimize operating costs. However, recent sustainability and…

  18. A new islanding detection technique for multiple mini hydro based on rate of change of reactive power and load connecting strategy

    International Nuclear Information System (INIS)

    Laghari, J.A.; Mokhlis, H.; Bakar, A.H.A.; Karimi, M.

    2013-01-01

    Highlights: • The requirement of DG interconnection with existing power system is discussed. • Various islanding detection techniques are discussed with their merits and demerits. • New islanding detection strategy is proposed for multiple mini hydro type DGs. • The proposed strategy is based on dq/dt and load connecting strategy. • The effectiveness of strategy is verified on various other cases. - Abstract: The interconnection of distributed generation (DG) into distribution networks is undergoing a rapid global expansion. It enhances the system’s reliability, while simultaneously reduces pollution problems related to the generation of electrical power. To fully utilize the benefits of DGs, certain technical issues need to be addressed. One of the most important issues in this context is islanding detection. This paper presents a new islanding detection technique that is suitable for multiple mini-hydro type DG units. The proposed strategy is based on the rate of change of reactive power and load connecting strategy to detect islanding within the system. For a large power mismatch, islanding is detected by rate of change of reactive power only. However, for a close power mismatch, the rate of change of reactive power initiates a load connecting strategy, which in turn alters the load on the distribution network. This load variation in the distribution network causes a variation in the rate of change of reactive power, which is utilized to distinguish islanding and other events. The simulation results show that the proposed strategy is effective in detecting islanding occurrence in a distribution network

  19. The Effect of Information Access Strategy on Power Consumption and Reliability in Wireless Sensor Network

    DEFF Research Database (Denmark)

    Tobgay, Sonam; Olsen, Rasmus Løvenstein; Prasad, Ramjee

    2013-01-01

    This paper examines the effect of different information access strategies on power consumption and information reliability, considering the wireless sensor network as the source of information. Basically, the paper explores three different access strategies, namely; reactive, periodic and hybrid...

  20. Implementation strategies for load center automation on the space station module/power management and distribution testbed

    Science.gov (United States)

    Watson, Karen

    1990-01-01

    The Space Station Module/Power Management and Distribution (SSM/PMAD) testbed was developed to study the tertiary power management on modules in large spacecraft. The main goal was to study automation techniques, not necessarily develop flight ready systems. Because of the confidence gained in many of automation strategies investigated, it is appropriate to study, in more detail, implementation strategies in order to find better trade-offs for nearer to flight ready systems. These trade-offs particularly concern the weight, volume, power consumption, and performance of the automation system. These systems, in their present implementation are described.

  1. A Pictorial Visualization of Normal Mode Vibrations of the Fullerene (C[subscript 60]) Molecule in Terms of Vibrations of a Hollow Sphere

    Science.gov (United States)

    Dunn, Janette L.

    2010-01-01

    Understanding the normal mode vibrations of a molecule is important in the analysis of vibrational spectra. However, the complicated 3D motion of large molecules can be difficult to interpret. We show how images of normal modes of the fullerene molecule C[subscript 60] can be made easier to understand by superimposing them on images of the normal…

  2. PI[subscript 3]-Kinase Cascade Has a Differential Role in Acquisition and Extinction of Conditioned Fear Memory in Juvenile and Adult Rats

    Science.gov (United States)

    Slouzkey, Ilana; Maroun, Mouna

    2016-01-01

    The basolateral amygdala (BLA), medial prefrontal cortex (mPFC) circuit, plays a crucial role in acquisition and extinction of fear memory. Extinction of aversive memories is mediated, at least in part, by the phosphoinositide-3 kinase (P[subscript 3]K)/Akt pathway in adult rats. There is recent interest in the neural mechanisms that mediate fear…

  3. Multi objective large power system planning under sever loading condition using learning DE-APSO-PS strategy

    International Nuclear Information System (INIS)

    Mahdad, Belkacem; Srairi, K.

    2014-01-01

    Highlights: • An efficient planning strategy using DE and APSO in coordination with PS algorithm is proposed. • An interactive process is proposed to balance the exploitation and exploration capability of (DE-APSO) and PS. • Fuel cost, power loss, and voltage deviation considering loading condition are optimized. • The proposed strategy (DE-APSO-PS) is validated on three large practical test systems. - Abstract: This paper introduces an efficient planning strategy using new hybrid interactive differential evolution (DE), adaptive particle swarm optimization (APSO), and pattern search (PS) for solving the security optimal power flow (SOPF) considering multi distributed static VAR compensator (SVC). Three objective functions such as fuel cost, power loss and voltage deviation are considered and optimized considering sever loading conditions. The main idea of the proposed strategy is that variable controls are optimized based on superposition mechanism, the best solutions evaluated by DE and APSO at specified stages are communicated to PS to exploit new regions around this solution, alternatively the new solution achieved by PS is also communicated to DE and APSO, this interactive mechanism search between global and local search is to balance the exploitation and exploration capability which allows individuals from different methods to react more by learning and changing experiences. The robustness of the proposed strategy is tested and validated on large practical power system test (IEEE 118-Bus, IEEE 300-Bus, and 40 units). Comparison results with the standard global optimization methods such as DE, APSO PS and to other recent techniques showed the superiority and perspective of the proposed hybrid technique for solving practical power system problems

  4. A Wind Farm Active Power Dispatch Strategy for Fatigue Load Reduction

    DEFF Research Database (Denmark)

    Zhang, Baohua; N. Soltani, Mohsen; Hu, Weihao

    2016-01-01

    One of the biggest challenges in wind farm management is to cope with requirements from the grid companies and to optimize efficiency and minimize wear on wind turbines. This paper addresses an optimized active power dispatch strategy of a wind farm to reduce the fatigue load of wind turbines, wh...

  5. Control strategies for wind farm power optimization: LES study

    Science.gov (United States)

    Ciri, Umberto; Rotea, Mario; Leonardi, Stefano

    2017-11-01

    Turbines in wind farms operate in off-design conditions as wake interactions occur for particular wind directions. Advanced wind farm control strategies aim at coordinating and adjusting turbine operations to mitigate power losses in such conditions. Coordination is achieved by controlling on upstream turbines either the wake intensity, through the blade pitch angle or the generator torque, or the wake direction, through yaw misalignment. Downstream turbines can be adapted to work in waked conditions and limit power losses, using the blade pitch angle or the generator torque. As wind conditions in wind farm operations may change significantly, it is difficult to determine and parameterize the variations of the coordinated optimal settings. An alternative is model-free control and optimization of wind farms, which does not require any parameterization and can track the optimal settings as conditions vary. In this work, we employ a model-free optimization algorithm, extremum-seeking control, to find the optimal set-points of generator torque, blade pitch and yaw angle for a three-turbine configuration. Large-Eddy Simulations are used to provide a virtual environment to evaluate the performance of the control strategies under realistic, unsteady incoming wind. This work was supported by the National Science Foundation, Grants No. 1243482 (the WINDINSPIRE project) and IIP 1362033 (I/UCRC WindSTAR). TACC is acknowledged for providing computational time.

  6. Selection of energy source and evolutionary stable strategies for power plants under financial intervention of government

    Science.gov (United States)

    Hafezalkotob, Ashkan; Mahmoudi, Reza

    2017-09-01

    Currently, many socially responsible governments adopt economic incentives and deterrents to manage environmental impacts of electricity suppliers. Considering the Stackelberg leadership of the government, the government's role in the competition of power plants in an electricity market is investigated. A one-population evolutionary game model of power plants is developed to study how their production strategy depends on tariffs levied by the government. We establish that a unique evolutionary stable strategy (ESS) for the population exists. Numerical examples demonstrate that revenue maximization and environment protection policies of the government significantly affect the production ESS of competitive power plants. The results reveal that the government can introduce a green energy source as an ESS of the competitive power plants by imposing appropriate tariffs.

  7. IMAGE - REPUTATION - BRAND: STRATEGY OF FORMING OF VALUE OF THE POWER

    Directory of Open Access Journals (Sweden)

    Н Н Розанова

    2017-12-01

    Full Text Available Article is devoted to consideration of process of forming of valuable symbolical space of the Russian power in the context of forming of the new model of development of society determined as one of the priority directions of the Concept of long-term social and economic development of the Russian Federation for the period till 2020. This vector of development of the relations of the state and society is determined by the author as strategy of forming of the valuable relation to the power - the purposeful, system, jointly performed activities of the power and society for creation of valuable space of the Russian power through transformation and consecutive transition each other of the following symbolical categories of the power: “identity” - “image” - “reputation” - “brand”. Content of the specified categories is opened, interpretation of measurements of the valuable field of a brand of the power on the basis of model of a four-dimensional brand of T. Ged is offered. The special attention is paid to process of forming of reputation of the power as to a subject of independent author research, on the example of studying of reputation of the regional power of the Smolensk region.

  8. Strategy of investment in electricity sources--Market value of a power plant and the electricity market

    Science.gov (United States)

    Bartnik, R.; Hnydiuk-Stefan, A.; Buryn, Z.

    2017-11-01

    This paper reports the results of the investment strategy analysis in different electricity sources. New methodology and theory of calculating the market value of the power plant and value of the electricity market supplied by it are presented. The financial gain forms the most important criteria in the assessment of an investment by an investor. An investment strategy has to involve a careful analysis of each considered project in order that the right decision and selection will be made while various components of the projects will be considered. The latter primarily includes the aspects of risk and uncertainty. Profitability of an investment in the electricity sources (as well as others) is offered by the measures applicable for the assessment of the economic effectiveness of an investment based on calculations e.g. power plant market value and the value of the electricity that is supplied by a power plant. The values of such measures decide on an investment strategy in the energy sources. This paper contains analysis of exemplary calculations results of power plant market value and the electricity market value supplied by it.

  9. Evaluation of a fast power demand response strategy using active and passive building cold storages for smart grid applications

    International Nuclear Information System (INIS)

    Cui, Borui; Wang, Shengwei; Yan, Chengchu; Xue, Xue

    2015-01-01

    Highlights: • A fast power demand response strategy is developed for smart grid applications. • The developed strategy can provide immediate and stepped power demand reduction. • The demand reduction and building indoor temperature can be predicted accurately. • The demand reduction during the DR event is stable. - Abstract: Smart grid is considered as a promising solution in improving the power reliability and sustainability where demand response is one important ingredient. Demand response (DR) is a set of demand-side activities to reduce or shift electricity use to improve the electric grid efficiency and reliability. This paper presents the investigations on the power demand alternation potential for buildings involving both active and passive cold storages to support the demand response of buildings connected to smart grids. A control strategy is developed to provide immediate and stepped power demand reduction through shutting chiller(s) down when requested. The primary control objective of the developed control strategy is to restrain the building indoor temperature rise as to maintain indoor thermal comfort within certain level during the DR event. The chiller power reduction is also controlled under certain power reduction set-point. The results show that stepped and significant power reduction can be achieved through shutting chiller(s) down when requested. The power demand reduction and indoor temperature during the DR event can be also predicted accurately. The power demand reduction is stable which is predictable for the system operators

  10. Pelvic movement strategies and leg extension power in patients with end-stage medial compartment knee osteoarthritis: a cross-sectional study.

    Science.gov (United States)

    Kierkegaard, Signe; Jørgensen, Peter Bo; Dalgas, Ulrik; Søballe, Kjeld; Mechlenburg, Inger

    2015-09-01

    During movement tasks, patients with medial compartment knee osteoarthritis use compensatory strategies to minimise the joint load of the affected leg. Movement strategies of the knees and trunk have been investigated, but less is known about movement strategies of the pelvis during advancing functional tasks, and how these strategies are associated with leg extension power. The aim of the study was to investigate pelvic movement strategies and leg extension power in patients with end-stage medial compartment knee osteoarthritis compared with controls. 57 patients (mean age 65.6 years) scheduled for medial uni-compartmental knee arthroplasty, and 29 age and gender matched controls were included in this cross-sectional study. Leg extension power was tested with the Nottingham Leg Extension Power-Rig. Pelvic range of motion was derived from an inertia-based measurement unit placed over the sacrum bone during walking, stair climbing and stepping. Patients had lower leg extension power than controls (20-39 %, P 0.06). Furthermore, an inverse association (coefficient: -0.03 to -0.04; R (2) = 13-22 %) between leg extension power and pelvic range of motion during stair and step descending was found in the patients. Compared to controls, patients with medial compartment knee osteoarthritis use greater pelvic movements during advanced functional performance tests, particularly when these involve descending tasks. Further studies should investigate if it is possible to alter these movement strategies by an intervention aimed at increasing strength and power for the patients.

  11. Optimization Strategy for Economic Power Dispatch Utilizing Retired EV Batteries as Flexible Loads

    Directory of Open Access Journals (Sweden)

    Shubo Hu

    2018-06-01

    Full Text Available With the increasing penetration of new and renewable energy, incorporating variable adjustable power elements on the demand side is of particular interest. The utilization of batteries as flexible loads is a hot research topic. Lithium-ion batteries are key components in electric vehicles (EVs in terms of capital cost, mass and size. They are retired after around 5 years of service, but still retain up to 80% of their nominal capacity. Disposal of waste batteries will become a significant issue for the automotive industry in the years to come. This work proposes the use of the second life of these batteries as flexible loads to participate in the economic power dispatch. The characteristics of second life batteries (SLBs are varied and diverse, requiring a new optimization strategy for power dispatch at the system level. In this work, SLBs are characterized and their operating curves are obtained analytically for developing an economic power dispatch model involving wind farms and second life batteries. In addition, a dispatch strategy is developed to reduce the dispatch complex brought by the disperse spatial and time distribution of EVs and decrease the system operating cost by introducing incentive and penalty costs in regulating the EV performance. In theory, SLBs are utilized to reduce the peak-valley difference of power loads and to stabilize the power system. Test results based on a ten-unit power system have verified the effectiveness of the proposed dispatch model and the economic benefit of utilizing SLBs as flexible loads in power systems. This work may provide a viable solution to the disposal of waste batteries from EVs and to the stable operation of fluctuating power systems incorporating stochastic renewable energy.

  12. Strategy and implementation of resources control of key equipments in nuclear power plant

    International Nuclear Information System (INIS)

    Zha Qing

    2014-01-01

    The strategic resources of the construction of nuclear power plant, which include the main equipment of nuclear island, heavy forgings, the bottleneck equipment and strategic materials, is one of the key issues in the construction of nuclear power projects. The control of these strategic resources has become the focus of competition in industry and the major nuclear power groups are willing to fight for this huge advantages. The resource control strategies of key equipment of nuclear power projects are analyzed in this paper. This paper put forward specific measures and methods for the strategic resources control. By the application to a plurality of nuclear power engineering construction projects, these specific measures and methods achieved good results and will be with important guidance and reference for the construction of future nuclear power projects in China. (author)

  13. The Effects of the Rope Jump Training Program in Physical Education Lessons on Strength, Speed and VO[subscript 2] Max in Children

    Science.gov (United States)

    Eler, Nebahat; Acar, Hakan

    2018-01-01

    The aim of this study is to examine the effects of rope-jump training program in physical education lessons on strength, speed and VO[subscript 2] max in 10-12 year old boys. 240 male students; rope-jump group (n = 120) and control group (n = 120) participated in the study. Rope-Jump group continued 10 weeks of regular physical education and sport…

  14. Regulatory oversight strategy for chemistry program at Canadian nuclear power plants

    International Nuclear Information System (INIS)

    Kameswaran; Ram

    2012-09-01

    Chemistry program is one of the essential programs for the safe operation of a nuclear power plant. It helps to ensure the necessary integrity, reliability and availability of plant structures, systems and components important to safety. Additionally, the program plays an important role in asset preservation, limiting radiation exposure and environmental protection. A good chemistry program will minimize corrosion of materials, reduce activation products, minimize of the buildup of radioactive material leading to occupational radiation exposure and it helps limit the release of chemicals and radioactive materials to the environment. The legal basis for the chemistry oversight at Canadian NPPs is established by the Nuclear Safety and Control Act and its associated regulations. It draws on the Canadian Nuclear Safety Commission's regulatory framework and NPP operating license conditions that include applicable standards such as CAN/CSA N286-05 Management System Requirements for Nuclear Power Plants. This paper focuses on the regulatory oversight strategy used in Canada to assess the performance of chemistry program at the nuclear power plants (NPPs) licensed by CNSC. The strategy consists of a combination of inspection and performance monitoring activities. The activities are further supported from information gathered through staff inspections of cross-cutting areas such as maintenance, corrective-action follow-ups, event reviews and safety related performance indicators. (authors)

  15. Optimal recharge and driving strategies for a battery-powered electric vehicle

    Directory of Open Access Journals (Sweden)

    Lee W. R.

    1999-01-01

    Full Text Available A major problem facing battery-powered electric vehicles is in their batteries: weight and charge capacity. Thus, a battery-powered electric vehicle only has a short driving range. To travel for a longer distance, the batteries are required to be recharged frequently. In this paper, we construct a model for a battery-powered electric vehicle, in which driving strategy is to be obtained such that the total travelling time between two locations is minimized. The problem is formulated as an optimization problem with switching times and speed as decision variables. This is an unconventional optimization problem. However, by using the control parametrization enhancing technique (CPET, it is shown that this unconventional optimization is equivalent to a conventional optimal parameter selection problem. Numerical examples are solved using the proposed method.

  16. Strategies for development and CO2 abatement in China`s power industry

    Energy Technology Data Exchange (ETDEWEB)

    Ying, R.

    1996-12-31

    Chinese Government has set a series sustainable energy development policies and strategies to alleviate atmospheric pollution and to mitigate the CO2 emission. Some major policies and measures that will be emphasized in China`s power industrial development will be addressed in this paper.

  17. Ukrainian Nuclear Society International Conference 'Strategy of the nuclear power development: The choice of Ukraine'

    International Nuclear Information System (INIS)

    Vishnevskij, I.N.; Trofimenko, A.P.

    2001-01-01

    Abstracts of the papers presented at the International Conference of the Ukrainian Nuclear Society 'Strategy of the nuclear power development'. The following problems are considered: present situation with the nuclear power and its safety; nuclear fuel cycle development; waste and spent nuclear fuel management; reactors' decommissioning issues; modernization of the NPP with WWER reactors; future reactors; economics of nuclear power; safety culture; legal and regulatory framework, state nuclear regulatory control; PR in nuclear power industry; staff training

  18. Inbound Marketing - the most important digital marketing strategy

    Directory of Open Access Journals (Sweden)

    PATRUTIU-BALTES Loredana

    2017-01-01

    Full Text Available Digital marketing has a major importance in the marketing strategy of any company regardless of sector, size or country of origin. Thus, more than ever, in order to remain competitive, companies are forced to exploit this form of marketing, which essentially can bring huge benefits at low costs. The main form of digital marketing is the inbound marketing, which represents an organic marketing form, based on the close relationship between the company and its prospects or customers, who have expressed their interest in the company’s products voluntarily (based on subscription to newsletters, blog, social networks, etc. and who have been attracted and involved by a high quality of the content marketing.

  19. A Comprehensive Strategy for Accurate Reactive Power Distribution, Stability Improvement, and Harmonic Suppression of Multi-Inverter-Based Micro-Grid

    Directory of Open Access Journals (Sweden)

    Henan Dong

    2018-03-01

    Full Text Available Among the issues of accurate power distribution, stability improvement, and harmonic suppression in micro-grid, each has been well studied as an individual, and most of the strategies about these issues aim at one inverter-based micro-grid, hence there is a need to establish a model to achieve these functions as a whole, aiming at a multi-inverter-based micro-grid. This paper proposes a comprehensive strategy which achieves this goal successfully; since the output voltage and frequency of micro-grid all consist of fundamental and harmonic components, the strategy contains two parts accordingly. On one hand, a fundamental control strategy is proposed upon the conventional droop control. The virtual impedance is introduced to solve the problem of accurate allocation of reactive power between inverters. Meanwhile, a secondary power balance controller is added to improve the stability of voltage and frequency while considering the aggravating problem of stability because of introducing virtual impedance. On the other hand, the fractional frequency harmonic control strategy is proposed. It can solve the influence of nonlinear loads, micro-grid inverters, and the distribution network on output voltage of inverters, which is focused on eliminating specific harmonics caused by the nonlinear loads, micro-grid converters, and the distribution network so that the power quality of micro-grid can be improved effectively. Finally, small signal analysis is used to analyze the stability of the multi-converter parallel system after introducing the whole control strategy. The simulation results show that the strategy proposed in this paper has a great performance on distributing reactive power, regulating and stabilizing output voltage of inverters and frequency, eliminating harmonic components, and improving the power quality of multi-inverter-based micro-grid.

  20. A new control strategy for nuclear power reactors

    International Nuclear Information System (INIS)

    Wakabayashi, H.; Sasaki, K.; Takegaki, M.

    1990-01-01

    A new automatic direct digital control strategy for nuclear power reactors is presented. It is based on a simple control logic of comparison between the available time (the time for the error signal to disappear) and the required time (the time for the time derivative to match that of the target trend). The method aims to control the system to an acceptable state within a minimum time under a number of restraints. The control capability of the method is shown for two typical transients. This method is generally applicable to process control in which time-optimal control based on the maximum principle is sought

  1. The strategy of experimental power reactor licensing in Indonesia

    International Nuclear Information System (INIS)

    Moch Djoko Birmano

    2015-01-01

    Currently, BATAN has being planned to develop Experimental Power Reactor (EPR), that is the research nuclear reactor that can generate power (electricity or heat). The EPR is planned will be built in the National Center for Research of Science and Technology (Puspiptek) area at Serpong, South Tangerang, Banten Province, with the choice of reactor types is HTGR with the power size of 10 MWth. As stated in the Act No. 10 year 1997 on Nuclear Power, that every construction and operation of nuclear reactors and other nuclear installations and decommissioning of nuclear reactors required to have a permit. Furthermore, the its implementation arrangements is regulated in Government Regulation (GR) No. 2 year 2014 on Licensing of Nuclear Installations and Nuclear Material Utilization, which contains the requirements and procedures for the licensing process since site, construction, commissioning, operation, and decommissioning, it means licensing is implemented during the activity of construction, operation and decommissioning of NPPs.While, for the more detailed licensing arrangements available in the guidelines of BAPETEN Chairman Regulation (BCR). This study was conducted to understand the legal and institutional aspects, types and stages, and the licensing process of RDE, and identify licensing strategy so that timely as planned. Methodologies used include the literature study, consultation with experts in BAPETEN, discussions in the national seminar including FGD. (author)

  2. The Acceptance Strategy for Nuclear Power Plant In Indonesia

    Science.gov (United States)

    Suhaemi, Tjipta; Syaukat, Achmad

    2010-06-01

    THE ACCEPTANCE STRATEGY FOR NUCLEAR POWER PLANT IN INDONESIA. Indonesia has planned to build nuclear power plants. Some feasibility studies have been conducted intensively. However, the processes of NPP introduction are still uncertain. National Energy Plan in Indonesia, which has been made by some governmental agencies, does not yet give positive impact to the government decision to construct the nuclear power plant (NPP). This paper discusses the process of NPP introduction in Indonesia, which has been colored with debate of stakeholder and has delayed decision for go-nuclear. The technology paradigm is used to promote NPP as an alternative of reliable energy resources. This paradigm should be complemented with international politic-economic point of view. The international politic-economic point of view shows that structural powers, consisting of security, production, finance, and knowledge structures, within which the NPP is introduced, have dynamic characteristics. The process of NPP introduction in Indonesia contains some infrastructure development (R&D, legislation, regulation, energy planning, site study, public acceptance efforts, etc), but they need a better coherent NPP implementation program and NPP Acceptance Program. Strategic patterns for NPP acceptance described in this paper are made by considering nuclear regulation development and the interest of basic domestic participation. The first NPP program in Indonesia having proven technology and basic domestic participation is and important milestone toward and optimal national energy-mix.

  3. Foundations of a long-term strategy for nuclear power development in Japan

    International Nuclear Information System (INIS)

    Murata, H.

    1975-01-01

    A long-term strategy for nuclear power developments in Japan is proposed. The situation in the world has greatly changed in the recent years due to the rise in oil prices as well as the considerable concern about the environmental problems caused by the nuclear power plants. Stress is being placed on the harmonization with the environmental protection rather than on the economical generation of the nuclear power. In order to meet the future requirements, five systems are given for the short, medium and long ranges beyond the year 2000. For the final stage a system is proposed that combines fusion-fission hybrid reactors with very high temperature gas cooled reactors to supply clean energy. (author)

  4. PMU Measurement-Based Intelligent Strategy for Power System Controlled Islanding

    Directory of Open Access Journals (Sweden)

    Yi Tang

    2018-01-01

    Full Text Available Controlled islanding is an effective remedy to prevent large-area blackouts in a power system under a critically unstable condition. When and where to separate the power system are the essential issues facing controlled islanding. In this paper, both tasks are studied to ensure higher time efficiency and a better post-splitting restoration effect. A transient stability assessment model based on extreme learning machine (ELM and trajectory fitting (TF is constructed to determine the start-up criterion for controlled islanding. This model works through prompt stability status judgment with ELM and selective result amendment with TF to ensure that the assessment is both efficient and accurate. Moreover, a splitting surface searching algorithm, subject to minimal power disruption, is proposed for determination of the controlled islanding implementing locations. A highlight of this algorithm is a proposed modified electrical distance concept defined by active power magnitude and reactance on transmission lines that realize a computational burden reduction without feasible solution loss. Finally, the simulation results and comparison analysis based on the New England 39-bus test system validates the implementation effects of the proposed controlled islanding strategy.

  5. Development of Emergency Operating Strategies for Beyond Design Basis External Event(BDBEE)s in Korean WH Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Duk-Joo; Lee, Seung-Chan; Sung, Je-Joong; Ha, Sang-Jun [KHNP CRI, Daejeon (Korea, Republic of); Hong, Soon-Joon; Hwang, Su-Hyun; Lee, Byung-Chul; Park, Kang-Min [FNC Tech. Co., Yongin (Korea, Republic of)

    2015-10-15

    Westinghouse developed and connected emergency operating procedures into a set of FLEX Support Guidelines(FSGs). This paper explains that Korean WH(Westinghouse) type nuclear power plants develop emergency operating strategies for ELAP(extended loss of all AC power), which include guidelines to use permanent and portable equipment as necessary to prevent core damage until AC power is restored from a reliable alternate source of AC power. The Korean emergency operating response strategies were developed to cope with a ELAP such as Fukushima event. The strategies include guidelines to prevent fuel damage using the FLEX equipment. Operators should take actions to prepare FLEX equipment within license basis SBO coping time. The loss of all AC power has been analyzed to identify the behavior of major NSSS process variables using RELAP computer code. The accident analysis showed that the plant does not result in fuel damage in 72 hours after an ELAP if operators take actions to cool RCS with opening of SG ADV in 5 gpm seal leak case. In this scenario, because ELAP is in process and all power cannot be used, operator should operate the FLEX equipment in order to actuate active equipment using the EOP fo SBO response. This strategy will prevent entering SAMG because this actions result in core cooling and stay in core exit temperature less than 650 .deg. C. Korean emergency operating guidelines(EOGs) will be developed using this strategies for response to the BDBEE.

  6. A strategy for improving the profitability of utility power plants in a deregulated industry

    International Nuclear Information System (INIS)

    Reinhart, E.R.

    1996-01-01

    When deregulation of the utility industry becomes a reality in the near future, power plant managers and engineers will face a completely changed business climate. Surviving in a competitive business world will require a dramatic alteration in the way most utility power plants are maintained and upgraded, and in their budget planning. Strategies will have to be developed and implemented that follow the guidelines of good business practices in competitive industries. Some utilities have already started to reduce overhead maintenance costs. Key aspects of their programs can serve as examples to other utilities who want to develop a strategy to improve their operating cost effectiveness. Cost-cutting measures have included development of procedures and data bases that allowed utilities to become independent of original equipment manufacturer (OEM) support and to keep their costs for maintenance, repairs, and replacement of power plant components to a minimum. Also, scheduled power plant outages based on the concepts of reliability-centered maintenance (Smith, 1993), remaining life assessment, and advanced integrity monitors instead of a fixed calendar (Swanekamp, 1996), have allowed utilities to extend the time between some outages by several years. These and other innovative approaches will become critical to power plants operating in the new, deregulated business climate. Examples of actual cost savings are presented here

  7. Strategies for monitoring and training strength and power in elite rugby union players.

    OpenAIRE

    Gannon, Edward

    2015-01-01

    Rugby union requires high levels of strength and power in order to support the physical requirements of the game. The competitive structure of rugby union in the English premiership places limitations on the time available for players’ physical development. The aim of this thesis was to analyse the scope and magnitude of strength and power adaptation potential, whilst identifying effective training strategies to support physical development in professional rugby union players. Chapter 3 monit...

  8. Experimental Research and Control Strategy of Pumped Storage Units Dispatching in the Taiwan Power System Considering Transmission Line Limits

    Directory of Open Access Journals (Sweden)

    Ming-Tse Kuo

    2013-07-01

    Full Text Available Taiwan’s power system is isolated and not supported by other interconnected systems. Consequently, the system frequency immediately reflects changes in the system loads. Pumped storage units are crucial for controlling power frequency. These units provide main or auxiliary capacities, reducing the allocation of frequency-regulating reserve (FRR and further reducing generation costs in system operations. Taiwan’s Longmen Nuclear Power Plant is set to be converted for commercial operations, which will significantly alter the spinning reserves in the power system. Thus, this study proposes a safe and economic pumped storage unit dispatch strategy. This strategy is used to determine the optimal FRR capacity and 1-min recovery frequency in a generator failure occurrence at the Longmen Power Plant. In addition, this study considered transmission capacity constraints and conducted power flow analysis of the power systems in Northern, Central, and Southern Taiwan. The results indicated that, in the event of a failure at Longmen Power Plant, the proposed strategy can not only recover the system frequency to an acceptable range to prevent underfrequency load-shedding, but can also mitigate transmission line overloading.

  9. Long Term Asset Management Strategy for Refurbishment and Replacement of Nuclear Power Plants in Korea

    International Nuclear Information System (INIS)

    Boo, M.H.; Lee, J.G.; Park, J.S.

    2012-01-01

    LTAM strategy was developed for the component level to efficiently manage aging and obsolescence. Systematic monitoring and proactive measures against aging mechanism will reduce unplanned loss due to failure of large components. Also, financial risk for lost power production will be minimized on the basis of fleet-wide LTAM strategies. (author)

  10. Research on intelligent power consumption strategy based on time-of-use pricing

    Science.gov (United States)

    Fu, Wei; Gong, Li; Chen, Heli; He, Yu

    2017-06-01

    In this paper, through the analysis of shortcomings of the current domestic and foreign household power consumption strategy: Passive way of power consumption, ignoring the different priority of electric equipment, neglecting the actual load pressure of the grid, ignoring the interaction with the user, to decrease the peak-valley difference and improve load curve in residential area by demand response (DR technology), an intelligent power consumption scheme based on time-of-use(TOU) pricing for household appliances is proposed. The main contribution of this paper is: (1) Three types of household appliance loads are abstracted from different operating laws of various household appliances, and the control models and DR strategies corresponding to these types are established. (2) The fuzzified processing for the information of TOU price, which is based on the time intervals, is performed to get the price priority, in accordance with such DR events as the maximum restricted load of DR, the time of DR and the duration of interruptible load and so on, the DR control rule and pre-scheduling mechanism are led in. (3) The dispatching sequence of household appliances in the control and scheduling queue are switched and controlled to implement the equilibrium of peak and valley loads. The equilibrium effects and economic benefits of power system by pre-scheduling and DR dispatching are compared and analyzed by simulation example, and the results show that using the proposed household appliance control (HAC) scheme the overall cost of consumers can be reduced and the power system load can be alleviated, so the proposed household appliance control (HAC) scheme is feasible and reasonable.

  11. Comparison of two voltage control strategies for a wind power plant

    DEFF Research Database (Denmark)

    Martinez, Jorge; Kjær, Philip C.; Rodriguez, Pedro

    2011-01-01

    plants. This paper addresses the analysis of two different voltage control strategies for a wind power plant, i.e. decentralized and centralized voltage control schemes. The analysis has been performed using the equivalent and simplified transfer functions of the system. Using this representation......Larger percentages of wind power penetration translate to more demanding requirements from grid codes. Recently, voltage support at the point of connection has been introduced by several grid codes from around the world, thus, making it important to analyze this control when applied to wind power......, it is possible to investigate the influence of the plant control gain, short circuit ratio, and time delays on the system stability, as well as the fulfillment of the design requirements. The implemented plant voltage control is based on a slope voltage controller, which calculates the references to be sent...

  12. An Optimal Reactive Power Control Strategy for a DFIG-Based Wind Farm to Damp the Sub-Synchronous Oscillation of a Power System

    Directory of Open Access Journals (Sweden)

    Bin Zhao

    2014-05-01

    Full Text Available This study presents the auxiliary damping control with the reactive power loop on the rotor-side converter of doubly-fed induction generator (DFIG-based wind farms to depress the sub-synchronous resonance oscillations in nearby turbogenerators. These generators are connected to a series capacitive compensation transmission system. First, the damping effect of the reactive power control of the DFIG-based wind farms was theoretically analyzed, and a transfer function between turbogenerator speed and the output reactive power of the wind farms was introduced to derive the analytical expression of the damping coefficient. The phase range to obtain positive damping was determined. Second, the PID phase compensation parameters of the auxiliary damping controller were optimized by a genetic algorithm to obtain the optimum damping in the entire subsynchronous frequency band. Finally, the validity and effectiveness of the proposed auxiliary damping control were demonstrated on a modified version of the IEEE first benchmark model by time domain simulation analysis with the use of DigSILENT/PowerFactory. Theoretical analysis and simulation results show that this derived damping factor expression and the condition of the positive damping can effectively analyze their impact on the system sub-synchronous oscillations, the proposed wind farms reactive power additional damping control strategy can provide the optimal damping effect over the whole sub-synchronous frequency band, and the control effect is better than the active power additional damping control strategy based on the power system stabilizator.

  13. Advanced nuclear power systems: Design, technology, safety and strategies for their deployment

    International Nuclear Information System (INIS)

    1994-01-01

    The objectives of the symposium were to provide high level decision makers with an overview of the discussion concerning the need for nuclear power and salient features of advanced nuclear power systems; a forum for discussing the design objectives and safety approaches for such systems and the views of regulatory bodies; a forum for identifying barriers to the deployment of these systems and for reviewing strategies to overcome these barriers; and a forum for reviewing options for international cooperation in the development and deployment of such systems. Refs, figs and tabs

  14. Peer Review Quality and Transparency of the Peer-Review Process in Open Access and Subscription Journals.

    Science.gov (United States)

    Wicherts, Jelte M

    2016-01-01

    Recent controversies highlighting substandard peer review in Open Access (OA) and traditional (subscription) journals have increased the need for authors, funders, publishers, and institutions to assure quality of peer-review in academic journals. I propose that transparency of the peer-review process may be seen as an indicator of the quality of peer-review, and develop and validate a tool enabling different stakeholders to assess transparency of the peer-review process. Based on editorial guidelines and best practices, I developed a 14-item tool to rate transparency of the peer-review process on the basis of journals' websites. In Study 1, a random sample of 231 authors of papers in 92 subscription journals in different fields rated transparency of the journals that published their work. Authors' ratings of the transparency were positively associated with quality of the peer-review process but unrelated to journal's impact factors. In Study 2, 20 experts on OA publishing assessed the transparency of established (non-OA) journals, OA journals categorized as being published by potential predatory publishers, and journals from the Directory of Open Access Journals (DOAJ). Results show high reliability across items (α = .91) and sufficient reliability across raters. Ratings differentiated the three types of journals well. In Study 3, academic librarians rated a random sample of 140 DOAJ journals and another 54 journals that had received a hoax paper written by Bohannon to test peer-review quality. Journals with higher transparency ratings were less likely to accept the flawed paper and showed higher impact as measured by the h5 index from Google Scholar. The tool to assess transparency of the peer-review process at academic journals shows promising reliability and validity. The transparency of the peer-review process can be seen as an indicator of peer-review quality allowing the tool to be used to predict academic quality in new journals.

  15. Spent-fuel management strategies at Carolina Power ampersand Light Company

    International Nuclear Information System (INIS)

    Thompson, M.F. Jr.; Kunita, R.K.

    1990-01-01

    Carolina Power ampersand Light (CP ampersand L) Company serves customers in portions of both North and South Carolina, and operates the Robinson 2, Brunswick 1 and 2, and Harris nuclear units. Due first to licensing delays in the Allied General Nuclear Service reprocessing plant and then to actions and inactions by the federal government, CP ampersand L like other utilities, is concerned with the storage of spent fuel. Despite pool reracking to the maximum practical, further actions have been necessary; hence, CP ampersand L undertook efforts to make both dry storage and transshipment viable alternatives. Based on experience, it is found that while both dry storage and transshipment are viable options, transshipment is the better strategy for CP ampersand L. Dry storage will be maintained as an alternative strategy

  16. Emission operational strategy for combined cooling, heating, and power systems

    International Nuclear Information System (INIS)

    Fumo, Nelson; Mago, Pedro J.; Chamra, Louay M.

    2009-01-01

    Integrated Energy Systems (IES), as technology that use thermal activated components to recover waste heat, are energy systems that offer key solution to global warming and energy security through high overall energy efficiency and better fuel use. Combined Cooling, Heating, and Power (CCHP) Systems are IES that use recovered thermal energy from the prime mover to produce heating and cooling for the building. The CCHP operational strategy is critical and it has to be considered in a well designed system since it defines the ultimate goal for the benefits expected from the system. One of the most common operational strategies is the cost-oriented strategy, which allows the system to operate at the lowest cost. A primary energy strategy (PES) optimizes energy consumption instead of cost. However, as a result of the worldwide concern about global warming, projects that target reduction of greenhouse gas (GHG) emissions have gained a lot of interest. Therefore, for a CCHP system, an emission strategy (ES) would be an operational strategy oriented to minimize emission of pollutants. In this study, the use of an ES is proposed for CCHP systems targeted to reduce emission of pollutants. The primary energy consumption (PEC) reduction and carbon dioxide (CO 2 ) emission reduction obtained using the proposed ES are compared with results obtained from the use of a PES. Results show that lower emission of CO 2 is achieved with the ES when compared with the PES, which prove the advantage of the ES for the design of CCHP systems targeted to emissions reduction.

  17. Wireless power and data transmission strategies for next-generation capsule endoscopes

    International Nuclear Information System (INIS)

    Puers, R; Carta, R; Thoné, J

    2011-01-01

    Capsular endoscopy is becoming increasingly popular as an alternative to traditional gastro-intestinal (GI) examination techniques. However, the breakthrough of these devices is hindered by the limited amount of power that can be stored in a tiny pill. Most commercial devices use two watch batteries that can only provide an average power of 25 mW for about 6 h, certainly not sufficient for advanced robotic features. A dedicated inductive powering system, operating at 1 MHz to limit the human body absorption, has been developed which was proven to support the transfer of over 300 mW. The system relies on a condensed set of orthogonal ferrite coils, embedded in the capsule, and an external unit based on a Helmholtz coil driven by a class E amplifier. Control data can be sent through the inductive link by modulating the power carrier, whereas a dedicated high data rate RF link is used to transfer the images from the capsule to the base station. Besides evaluating the compatibility with radio transmission, several demonstrators were assembled combining the wireless powering system with various locomotion strategies and LED illumination. This paper describes the design and implementation of the inductive powering system, its combination with data transmission techniques and the testing activity with other capsule-dedicated modules

  18. A robust control strategy for mitigating renewable energy fluctuations in a real hybrid power system combined with SMES

    Science.gov (United States)

    Magdy, G.; Shabib, G.; Elbaset, Adel A.; Qudaih, Yaser; Mitani, Yasunori

    2018-05-01

    Utilizing Renewable Energy Sources (RESs) is attracting great attention as a solution to future energy shortages. However, the irregular nature of RESs and random load deviations cause a large frequency and voltage fluctuations. Therefore, in order to benefit from a maximum capacity of the RESs, a robust mitigation strategy of power fluctuations from RESs must be applied. Hence, this paper proposes a design of Load Frequency Control (LFC) coordinated with Superconducting Magnetic Energy Storage (SMES) technology (i.e., an auxiliary LFC), using an optimal PID controller-based Particle Swarm Optimization (PSO) in the Egyptian Power System (EPS) considering high penetration of Photovoltaics (PV) power generation. Thus, from the perspective of LFC, the robust control strategy is proposed to maintain the nominal system frequency and mitigating the power fluctuations from RESs against all disturbances sources for the EPS with the multi-source environment. The EPS is decomposed into three dynamics subsystems, which are non-reheat, reheat and hydro power plants taking into consideration the system nonlinearity. The results by nonlinear simulation Matlab/Simulink for the EPS combined with SMES system considering PV solar power approves that, the proposed control strategy achieves a robust stability by reducing transient time, minimizing the frequency deviations, maintaining the system frequency, preventing conventional generators from exceeding their power ratings during load disturbances, and mitigating the power fluctuations from the RESs.

  19. Novel design methods and control strategies for oil and gas offshore power systems

    DEFF Research Database (Denmark)

    Pierobon, Leonardo

    content), or when the thermal stresses on the working fluid should be minimized. Additionally, the controller is demonstrated to improve the dynamic flexibility of the plant compared to the reference controller designed by the gas turbine manufacturer.The model predictive control can reduce the frequency......This doctoral thesis is devoted to the research of innovative design methods and control strategies for power systems supplying future and existing oshore oil and gas facilities.The author uses these methods to address five research challenges: i) the definitionof the optimal waste heat recovery...... technology, ii) the identification of the best working fluid to design ecient, light and cost-competitive waste heat recovery units, iii) the integration of dynamic criteria in the project phase to discard infeasible designs, iv) the development of a novel control strategy to optimally operate the power...

  20. The Research on Operation Strategy of Nuclear Power Plant with Multi-reactors

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Maoyao; Peng, Minjun; Cheng Shouyu [Harbin Engineering University, Harbin (China)

    2014-08-15

    In this paper, the operation characteristics and control strategy of nuclear power plant (NPP) with multi-modular pressurized water reactors (PWR) were researched through simulation. The main objective of this research was to ensure the coordinated operation and satisfy the convenience of turbine-generator and reactor's load adjustment in NPP with multi-reactors (MR). According to the operation characteristics of MR-NPP, the operation and control strategy was proposed, which was 'he average allocation of load for each reactor and maintaining average temperature of coolant at a constant? The control system was designed based the operation and control strategy. In order to research the operation characteristics and control strategy of MR-NPP, the paper established the transient analysis model which included the reactors and thermal hydraulic models, turbine model, could simulate and analyze on different operating conditions such as load reducing, load rising. Based on the proposed operation and control strategy and simulation models, the paper verified and validated the operation strategy and control system through load reducing, load rising. The results of research simulation showed that the operation strategy was feasible and can make the MR-NPP running safely as well as steadily on different operating conditions.

  1. The Research on Operation Strategy of Nuclear Power Plant with Multi-reactors

    International Nuclear Information System (INIS)

    Fang, Maoyao; Peng, Minjun; Cheng Shouyu

    2014-01-01

    In this paper, the operation characteristics and control strategy of nuclear power plant (NPP) with multi-modular pressurized water reactors (PWR) were researched through simulation. The main objective of this research was to ensure the coordinated operation and satisfy the convenience of turbine-generator and reactor's load adjustment in NPP with multi-reactors (MR). According to the operation characteristics of MR-NPP, the operation and control strategy was proposed, which was 'he average allocation of load for each reactor and maintaining average temperature of coolant at a constant? The control system was designed based the operation and control strategy. In order to research the operation characteristics and control strategy of MR-NPP, the paper established the transient analysis model which included the reactors and thermal hydraulic models, turbine model, could simulate and analyze on different operating conditions such as load reducing, load rising. Based on the proposed operation and control strategy and simulation models, the paper verified and validated the operation strategy and control system through load reducing, load rising. The results of research simulation showed that the operation strategy was feasible and can make the MR-NPP running safely as well as steadily on different operating conditions

  2. New maintenance strategy of Tokyo Electric Power Company and Fukushima Dai-ichi Nuclear Power Plant for effective ageing management and safe long-term operation

    International Nuclear Information System (INIS)

    Inagaki, Takeyuki; Yamashita, Norimichi

    2009-01-01

    Fukushima Dai-ichi Nuclear Power Plant is the oldest among three nuclear power plants owned and operated by Tokyo Electric Power Company, which consists of six boiling water reactor units. The commercial operation of Unit 1 was commenced in 1971 (37 years old) and Unit 6 in 1978 (29 years old). Currently ageing degradations of systems, structures and components are managed through maintenance programs, component replacement/refurbishment programs and long-term maintenance plans. The long-term maintenance plans are established through ageing management component replacement/refurbishment programs reviews performed before the 30th year of operation and they are for safe and reliable operation after 30 years (long-term operation). However the past maintenance actions and past component replacement/refurbishment programs were not always proactive and past operational experience and maintenance practices suggest that effective/proactive ageing management programs be introduced in earlier stage of the plant operation. In this circumstance, Tokyo Electric Power Company and Fukushima Dai-ichi Nuclear Power Plant are setting up a new maintenance strategy that includes 1) improving the normal maintenance programs by using ageing degradation data, 2) effective use of information on internal/external operational experience and maintenance practices related to ageing, and 3) proactive component/equipment refurbishment programs during a refreshment outage for safe and reliable long-term operation. To accomplish the goal of this strategy, strengthening engineering capability of plant staff members is a crucial required for the plant. The objective of this paper is to briefly explain main results ageing management reviews, past and current significant ageing issues and management programs against them, and the new maintenance strategy established by Tokyo Electric Power Company and Fukushima Dai-ichi Nuclear Power Plant. (author)

  3. Management strategies for nuclear power plant outages

    International Nuclear Information System (INIS)

    2006-01-01

    More competitive energy markets have significant implications for nuclear power plant operations, including, among others, the need for more efficient use of resources and effective management of plant activities such as on-line maintenance and outages. Outage management is a key factor for safe, reliable and economic plant performance and involves many aspects: plant policy, coordination of available resources, nuclear safety, regulatory and technical requirements, and all activities and work hazards, before and during the outage. The IAEA has produced this report on nuclear power plant outage management strategies to provide both a summary and an update of a follow-up to a series of technical documents related to practices regarding outage management and cost effective maintenance. The aim of this publication is to identify good practices in outage management: outage planning and preparation, outage execution and post-outage review. As in in the related technical documents, this report aims to communicate these practices in such a way that they can be used by operating organizations and regulatory bodies in Member States. The report was prepared as part of an IAEA project on continuous process improvement. The objective of this project is to increase Member State capabilities in improving plant performance and competitiveness through the utilization of proven engineering and management practices developed and transferred by the IAEA

  4. Strategies for Financing Large-scale Carbon Capture and Storage Power Plants in China

    OpenAIRE

    Liang, X.; Liu, H.; Reiner, D.

    2014-01-01

    Building on previous stakeholder consultations from 2006 to 2010, we conduct a financial analysis for a generic CCS power plant in China. In comparison with conventional thermal generation technologies, a coal-fired power plant with CCS requires either a 70% higher on-grid electricity tariff or carbon price support of approximately US$50/tonne CO2 in the absence of any other incentive mechanisms or financing strategies. Given the difficulties of relying on any one single measure to finance a ...

  5. Robustness analysis of complex networks with power decentralization strategy via flow-sensitive centrality against cascading failures

    Science.gov (United States)

    Guo, Wenzhang; Wang, Hao; Wu, Zhengping

    2018-03-01

    Most existing cascading failure mitigation strategy of power grids based on complex network ignores the impact of electrical characteristics on dynamic performance. In this paper, the robustness of the power grid under a power decentralization strategy is analysed through cascading failure simulation based on AC flow theory. The flow-sensitive (FS) centrality is introduced by integrating topological features and electrical properties to help determine the siting of the generation nodes. The simulation results of the IEEE-bus systems show that the flow-sensitive centrality method is a more stable and accurate approach and can enhance the robustness of the network remarkably. Through the study of the optimal flow-sensitive centrality selection for different networks, we find that the robustness of the network with obvious small-world effect depends more on contribution of the generation nodes detected by community structure, otherwise, contribution of the generation nodes with important influence on power flow is more critical. In addition, community structure plays a significant role in balancing the power flow distribution and further slowing the propagation of failures. These results are useful in power grid planning and cascading failure prevention.

  6. Design method of a power management strategy for variable battery capacities range-extended electric vehicles to improve energy efficiency and cost-effectiveness

    International Nuclear Information System (INIS)

    Du, Jiuyu; Chen, Jingfu; Song, Ziyou; Gao, Mingming; Ouyang, Minggao

    2017-01-01

    Energy management strategy and battery capacity are the primary factors for the energy efficiency of range-extended electric buses (REEBs). To improve the energy efficiency of REEBs developed by Tsinghua University, an optimal design method of global optimization-based strategy is investigated. It is real-time and adaptive to variable traction battery capacities of series REEBs. For simulation, the physical model of REEB and key components are established. The optimal strategy is first extracted by the power split ratio (PSR) from REEB simulation result with dynamic program (DP) algorithm. The power distribution map is obtained by series simulations for variable battery capacity options. The control law for developing optimal strategy are achieved by cluster regression for power distribution data. To verify the effect of the proposed energy management strategy, characteristics of powertrain, energy efficiency, operating cost, and computing time are ultimately analyzed. Simulation results show that the energy efficiency of the global optimization-based strategy presented in this paper is similar to that of the DP strategy. Therefore, the overall energy efficiency can be significantly improved compared with that of the CDCS strategy, and operating costs can be substantially reduced. The feasibility of candidate control strategies is thereby assessed via the employment of variable parameters. - Highlights: • Analysis method of powertrain energy efficiency and power distribution is proposed. • The power distribution rules of strategy with variable battery capacities are achieved. • The parametric method of proposed PSR-RB strategy is presented. • The energy efficiency of powertrain is analysis by flow analysis method. • The energy management strategy is global optimization-based and real-time.

  7. Annual report - Companhia Paulista de Forca e Luz - 1998

    International Nuclear Information System (INIS)

    1999-03-01

    The annual report of 1998 of Companhia Paulista de Forca e Luz - Brazilian electric power company - introduces the next main topics: management's report; economic scenario; the new brazilian energy sector; market strategy; business opportunities - electricity tariffs, economic and financial performance; financial aspects - domestic market, international market, capital subscriptions; investments; performance of CPFL; investors' relations, human resources; contribution to the community - personnel, cultural events, social contribution; environmental concern; and financial statements

  8. The alternative strategies of the development of the nuclear power industry in the 21st century

    Science.gov (United States)

    Goverdovskii, A. A.; Kalyakin, S. G.; Rachkov, V. I.

    2014-05-01

    This paper emphasizes the urgency of scientific-and-technical and sociopolitical problems of the modern nuclear power industry without solving of which the transition from local nuclear power systems now in operation to a large-scale nuclear power industry would be impossible. The existing concepts of the longterm strategy of the development of the nuclear power industry have been analyzed. On the basis of the scenarios having been developed it was shown that the most promising alternative is the orientation towards the closed nuclear fuel cycle with fast neutron reactors (hereinafter referred to as fast reactors) that would meet the requirements on the acceptable safety. It was concluded that the main provisions of "The Strategy of the Development of the Nuclear Power Industry of Russia for the First Half of the 21st Century" approved by the Government of the Russian Federation in the year 2000 remain the same at present as well, although they require to be elaborated with due regard for new realities in the market for fossil fuels, the state of both the Russian and the world economy, as well as tightening of requirements related to safe operation of nuclear power stations (NPSs) (for example, after the severe accident at the Fukushima nuclear power station, Japan) and nonproliferation of nuclear weapons.

  9. Substation Reactive Power Regulation Strategy

    Science.gov (United States)

    Zhang, Junfeng; Zhang, Chunwang; Ma, Daqing

    2018-01-01

    With the increasing requirements on the power supply quality and reliability of distribution network, voltage and reactive power regulation of substations has become one of the indispensable ways to ensure voltage quality and reactive power balance and to improve the economy and reliability of distribution network. Therefore, it is a general concern of the current power workers and operators that what kind of flexible and effective control method should be used to adjust the on-load tap-changer (OLTC) transformer and shunt compensation capacitor in a substation to achieve reactive power balance in situ, improve voltage pass rate, increase power factor and reduce active power loss. In this paper, based on the traditional nine-zone diagram and combining with the characteristics of substation, a fuzzy variable-center nine-zone diagram control method is proposed and used to make a comprehensive regulation of substation voltage and reactive power. Through the calculation and simulation of the example, this method is proved to have satisfactorily reconciled the contradiction between reactive power and voltage in real-time control and achieved the basic goal of real-time control of the substation, providing a reference value to the practical application of the substation real-time control method.

  10. Requirements on future energy supply. Analysis on the demand of future power plant capacity and strategy for a sustainable power utilization in Germany

    International Nuclear Information System (INIS)

    2003-08-01

    This strategy paper was drawn up with a view to maximum ecological compatibility of pwer plant modernization and sustainable power generation and use. The first part of the paper analyzes the power plants to be decommissioned on a medium-term basis and - against the background of several different scenarios for future power demand - an estimate of power plant capacities required by 2020. The second part describes the goals and concrete requirements of sustainable energy use. In the final part, the available instruments are presented, and those instruments are recommended that will be best suited for making power demand and supply efficient, sustainable and environment-friend.y [de

  11. Economy and Society: Strategies for a More Equal Distribution of Societal Power

    Directory of Open Access Journals (Sweden)

    Erich Hoedl

    2017-10-01

    Full Text Available Unequal distribution of societal power is to a large extent responsible for poverty, hunger, the destruction of nature, and inhuman living conditions. From the perspective of its redistribution, we distinguish three basic means of power: The ownership of material and immaterial properties, the kind of organisation and the values according to which properties and their organisation are handled. This framework permits us to identify crucial power structures in less industrialised and industrial countries and within the financial, real productive, political and social subsystems of the society and allows us to sketch strategies for redistribution of societal power: Industrial countries have to reduce their real and financial capital inputs in favour of higher human capital investments and increase their direct investments in less industrialised countries, supported by a Global Marshall Plan. Less industrialised countries need to enhance both their industrial and alternative sectors, establish more democratic structures and human-centered educational systems. By these cooperative strategies the costs of former colonialism can be partly refunded. The main obstacle for such global cooperation is the global financial system, which has to be decentralised towards a multi-currency system, including regional currencies and barter. In the real productive sector, financial governance and capital-oriented hierarchies should be markedly reduced, which will increase creativity and productivity of work, underpinned by an enlarged human-centered education. Redistributing the prevailing power of the financial and productive sector rests considerably on democratic governance, which has to include increasing informal and legitimate interests and prevent plutocratic tendencies. For this, an economic democracy should be evolved where each individual not only has a vote, but also a guaranteed minimum income. Individual security, welfare and well-being are the

  12. Design of intelligent comfort control system with human learning and minimum power control strategies

    International Nuclear Information System (INIS)

    Liang, J.; Du, R.

    2008-01-01

    This paper presents the design of an intelligent comfort control system by combining the human learning and minimum power control strategies for the heating, ventilating and air conditioning (HVAC) system. In the system, the predicted mean vote (PMV) is adopted as the control objective to improve indoor comfort level by considering six comfort related variables, whilst a direct neural network controller is designed to overcome the nonlinear feature of the PMV calculation for better performance. To achieve the highest comfort level for the specific user, a human learning strategy is designed to tune the user's comfort zone, and then, a VAV and minimum power control strategy is proposed to minimize the energy consumption further. In order to validate the system design, a series of computer simulations are performed based on a derived HVAC and thermal space model. The simulation results confirm the design of the intelligent comfort control system. In comparison to the conventional temperature controller, this system can provide a higher comfort level and better system performance, so it has great potential for HVAC applications in the future

  13. Damping control strategies of inter-area low-frequency oscillation for DFIG-based wind farms integrated into a power system

    DEFF Research Database (Denmark)

    Li, Hui; Liu, Shengquan; Ji, Haiting

    2014-01-01

    on the power system stabilizer (PSS) control method. Transient simulation on different damping gain coefficients are conducted for justification. Following the OTEF mechanism analysis, an additional fuzzy damping control strategy with the active/reactive power loop is proposed by identifying the oscillation......This study investigates the inter-area low-frequency damping control strategies of a doubly fed induction generator (DFIG)-based wind farm through oscillation transient energy function (OTEF) analysis. Based on the OTEF descent expressions, the feasibility of damping the inter-area low...... oscillation of the wind turbine shaft. The proposed additional fuzzy control strategy with the active/reactive power loop has better damping performance than the presented PSS control, especially for damping the inter-area low-frequency oscillation....

  14. Operation strategy for grid-tied DC-coupling power converter interface integrating wind/solar/battery

    Science.gov (United States)

    Jou, H. L.; Wu, J. C.; Lin, J. H.; Su, W. N.; Wu, T. S.; Lin, Y. T.

    2017-11-01

    The operation strategy for a small-capacity grid-tied DC-coupling power converter interface (GDPCI) integrating wind energy, solar energy and battery energy storage is proposed. The GDPCI is composed of a wind generator, a solar module set a battery bank, a boost DC-DC power converter (DDPC), a bidirectional DDPC power converter, an AC-DC power converter (ADPC) and a five-level DC-AC inverter (DAI). A solar module set, a wind generator and a battery bank are coupled to the common DC bus through the boost DDPC, the ADPC and the bidirectional DDPC, respectively. For verifying the performance of the GDPCI under different operation modes, computer simulation is carried out by PSIM.

  15. Carbon Emission Impact for Energy Strategy in which All Non-CSS Coal Power Plants Are Replaced by Nuclear Power Plants

    International Nuclear Information System (INIS)

    Knapp, V.; Matijevic, M.; Pevec, D.; Lale, D.

    2016-01-01

    The Paris climate conference recognized the urgency of measures to mitigate climate changes and achieved an agreement on the targets for future decades. We wish to show that advanced LWR initiated nuclear strategy can offer us long term carbon free energy future. Human action is putting carbon dioxide into atmosphere where it resides effectively for hundreds of years. We are forced to look ahead on the same time scale but we have much shorter time to act as we almost used up the quota of emission of carbon before disaster would be unavoidable, as shown in paper by Meinshausen et al. and IPCC report. We have to change our ways of relying on fossil fuel dramatically in the next few decades. It would be a change in use of fossil fuel which cannot be achieved with usual business practices. Arising awareness of reality and threat of global warming in parallel with fading promise of nuclear fusion and Carbon Capture and Storage (CCS) technology, should convince the public to accept nuclear fission contribution to climate change mitigation, at least for the climate critical years up to 2065. Nuclear fission has the additional value of supporting intermittent sources by covering the base load consumption. It can be available now, with proven reactors, such as advanced LWR reactors. Nuclear strategy in this paper outlines a proposal to replace all non-CCS coal power plants with nuclear power plants in the period 2025-2065. Assuming once through advanced LWR technology, one would need nuclear capacity of 1600 GW to replace coal power plants in the period 2025-2065. Corresponding reduction of emission would amount to 11.8 Gt of CO2. This energy strategy would reduce carbon emission by approximately 22 percent in the year 2065. The annual uranium requirements and the cumulative uranium requirements, as well as the annual plutonium production and cumulative plutonium production for the proposed nuclear strategy are determined. A possibility of larger reduction of carbon

  16. Evaluation of BWROG EPG level/power control strategy for Vermont Yankee

    International Nuclear Information System (INIS)

    Chandola, V.; Robichaud, J.D.

    1987-01-01

    The current Boiling Water Reactor Owner's Group (BWROG) emergency procedure guidelines (EPGs) direct reactor operators to manually lower the reactor pressure vessel (RPV) water level to the top of active fuel (TAF) during an anticipated transient without scram (ATWS) event. Lowering the water level reduces the core inlet flow, thereby reducing core power. However, reducing water level is contrary to current operator training, which requires that normal RPV water level be maintained to assure core cooling. In addition, the indicated water level near TAF using cold calibrated level instrumentation may not be reliable, which could potentially result in uncovering the core. This paper evaluates the EPGs' level/power control strategy for the Vermont Yankee plant and proposes alternative to the BWROG guidelines as applied to ATWS response

  17. Status of the Romanian nuclear power program and the strategy related to the public information

    International Nuclear Information System (INIS)

    Stiopol, Mihaela; Chirica, Teodor

    1999-01-01

    The year 1997 represented for the Romanian nuclear power sector the year of the performances and capabilities proved Cernavoda NPP s unit operation, after one year of successful operation. Good performances of this unit could represent a positive impact on further development of nuclear power in Romania, considering first the completion of Unit 2 and for National Heavy Water Reactor Program. On the other hand, 'The years of 1997 and 1998 marked for the Romanian Electricity Authority a new and completely different perception of the Romanian power sector'. Recently, the first step of the restructuring of power sector has been accomplished. The Romanian Government approved the creation of the National Power Grid Company and the moving-out of the nuclear activities. The present Nuclear Power Group from RENEL was transformed in a separate entity, the National 'Nuclear Ellectrica' Company, including three subsidiaries, no legal persons, one for nuclear power production CNE-PROD (Cernavoda Unit 1), one for nuclear power development CNE-INVEST (Cernavoda Unit 2 to 5) and one for nuclear fuel fabrication FCN (Pitesti Nuclear Fuel Plant). The other Units from Nuclear Power Group, such as the Heavy Water Plant - ROMAG, Center of Technology and Engineering for Nuclear Projects - CTON and the Institute for Nuclear Research-Pitesti - ICN have been transformed in a state owned company for nuclear activities. To better understand the aspects related to the nuclear power in Romania and the necessity of the continuation and development of a public information strategy based on the new look of the nuclear power sector, please, allow me to present you a few things with regard the Romanian nuclear program. The main targets of Public Information Program Strategy considered when assessing the strategy related to the public information were: education and built-up of a credibility on the construction of a nuclear power plant in general, and of the Cernavoda NPP, in particular; and once

  18. A proposed strategy for power optimization of a wind energy conversion system connected to the grid

    International Nuclear Information System (INIS)

    Taraft, S.; Rekioua, D.; Aouzellag, D.; Bacha, S.

    2015-01-01

    Highlights: • Wind energy conversion based doubly fed induction generator controlled by matrix converter. • Operation at both sub and super-synchronous regions is possible with the proposed drive system. • Double the power generated by the DFIG at a twice of speed rated. • Sliding mode control is used to achieve active and reactive power control. - Abstract: Many strategies have been developed in last decade to optimize power extracted from wind energy conversion system where many of them can produce only 30% more than the rated power. With the considered strategy, the generated wind power can reach twice its nominal value using a fast and reliable fully rugged electrical control. Indeed, by employing a suitable control technique where the produced power in super-synchronous mode is derived from both the stator and the rotor. Also, the rotor provided power in this case grows up 100% comparing to stator rated power. However, this solution permits to maintain the wind energy conversion system operation in its stable area. The considered system consists of a double fed induction generator whose stator is connected directly to the grid and its rotor is supplied by matrix converter. In this paper, the sliding mode approach to achieve active and reactive power control is used. This latter is combined with de Perturbation and Observation Maximum Power Point Tracking used in the second operation zone. The obtained simulations results are assessed and carried out using Matlab/Simulink package and show the performance and the effectiveness of the proposed control

  19. Virtual resistance-based control strategy for DC link regeneration protection and current sharing in uninterruptible power supply

    DEFF Research Database (Denmark)

    Lu, Jinghang; Guan, Yajuan; Savaghebi, Mehdi

    2017-01-01

    To address the DC link voltage regeneration issue in parallel Uninterruptible Power Supply (UPS) system, a DC link voltage protection (DCVP) method through online virtual resistance regulation is proposed. The proposed control strategy is able to protect the DC link from overvoltage that may...... trigger the protection mechanism of the UPS system. Moreover, a current sharing control strategy by regulating the virtual resistance is proposed to address the circulating current caused by the active power feeding. Finally, the feasibility of the proposed method is verified by experimental results from...

  20. Dynamic modeling and evaluation of solid oxide fuel cell - combined heat and power system operating strategies

    Science.gov (United States)

    Nanaeda, Kimihiro; Mueller, Fabian; Brouwer, Jacob; Samuelsen, Scott

    Operating strategies of solid oxide fuel cell (SOFC) combined heat and power (CHP) systems are developed and evaluated from a utility, and end-user perspective using a fully integrated SOFC-CHP system dynamic model that resolves the physical states, thermal integration and overall efficiency of the system. The model can be modified for any SOFC-CHP system, but the present analysis is applied to a hotel in southern California based on measured electric and heating loads. Analysis indicates that combined heat and power systems can be operated to benefit both the end-users and the utility, providing more efficient electric generation as well as grid ancillary services, namely dispatchable urban power. Design and operating strategies considered in the paper include optimal sizing of the fuel cell, thermal energy storage to dispatch heat, and operating the fuel cell to provide flexible grid power. Analysis results indicate that with a 13.1% average increase in price-of-electricity (POE), the system can provide the grid with a 50% operating range of dispatchable urban power at an overall thermal efficiency of 80%. This grid-support operating mode increases the operational flexibility of the SOFC-CHP system, which may make the technology an important utility asset for accommodating the increased penetration of intermittent renewable power.

  1. Intelligent approach to maximum power point tracking control strategy for variable-speed wind turbine generation system

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Whei-Min; Hong, Chih-Ming [Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung 80424 (China)

    2010-06-15

    To achieve maximum power point tracking (MPPT) for wind power generation systems, the rotational speed of wind turbines should be adjusted in real time according to wind speed. In this paper, a Wilcoxon radial basis function network (WRBFN) with hill-climb searching (HCS) MPPT strategy is proposed for a permanent magnet synchronous generator (PMSG) with a variable-speed wind turbine. A high-performance online training WRBFN using a back-propagation learning algorithm with modified particle swarm optimization (MPSO) regulating controller is designed for a PMSG. The MPSO is adopted in this study to adapt to the learning rates in the back-propagation process of the WRBFN to improve the learning capability. The MPPT strategy locates the system operation points along the maximum power curves based on the dc-link voltage of the inverter, thus avoiding the generator speed detection. (author)

  2. Renewable energy strategies to overcome power shortage in Kurdistan Region of Iraq

    Directory of Open Access Journals (Sweden)

    Al-Din Salar Salah Muhy

    2017-01-01

    Full Text Available The aim of this paper is to investigate the possibility of applying renewable energy strategies in Kurdistan Region of Iraq to overcome the shortage of electricity supply. Finding alternative renewable sources could overcome the problem. The renewable energy will reduce CO2 emission in the cities which considers the main source of pollution. That will participate in reducing the effect of global warming. The study tries to investigate the direct solar renewable energy through two of the main renewable energy categories to produce electricity based on a survey of literature review. Photovoltaic and wind power technologies are possible to be conducted in the region to overcome power shortage.

  3. The Influence of Gender on the Likelihood of Using Soft Social Power Strategies in School Consultation

    Science.gov (United States)

    Getty, Kimberly C.; Erchul, William P.

    2009-01-01

    The social power typology developed originally by French and Raven in 1959 and revised by Raven in 1965 and 1992 was applied to study school consultation. Specifically, we investigated how the gender of school psychologist consultants and teacher consultees influence how likely consultants are to use soft power strategies, identified as those…

  4. Plasma Profile and Shape Optimization for the Advanced Tokamak Power Plant, ARIES-AT

    International Nuclear Information System (INIS)

    Kessel, C.E.; Mau, T.K.; Jardin, S.C.; Najmabadi, F.

    2001-01-01

    An advanced tokamak plasma configuration is developed based on equilibrium, ideal-MHD stability, bootstrap current analysis, vertical stability and control, and poloidal-field coil analysis. The plasma boundaries used in the analysis are forced to coincide with the 99% flux surface from the free-boundary equilibrium. Using an accurate bootstrap current model and external current-drive profiles from ray-tracing calculations in combination with optimized pressure profiles, beta(subscript N) values above 7.0 have been obtained. The minimum current drive requirement is found to lie at a lower beta(subscript N) of 5.4. The external kink mode is stabilized by a tungsten shell located at 0.33 times the minor radius and a feedback system. Plasma shape optimization has led to an elongation of 2.2 and triangularity of 0.9 at the separatrix. Vertical stability could be achieved by a combination of tungsten shells located at 0.33 times the minor radius and feedback control coils located behind the shield. The poloidal-field coils were optimized in location and current, providing a maximum coil current of 8.6 MA. These developments have led to a simultaneous reduction in the power plant major radius and toroidal field

  5. Impact of Financing Instruments and Strategies on the Wind Power Production Costs: A Case of Lithuania

    Science.gov (United States)

    Bobinaite, V.; Konstantinaviciute, I.

    2018-04-01

    The paper aims at demonstrating the relevance of financing instruments, their terms and financing strategies in relation to the cost of wind power production and the ability of wind power plant (PP) to participate in the electricity market in Lithuania. The extended approach to the Levelized Cost of Energy (LCOE) is applied. The feature of the extended approach lies in considering the lifetime cost and revenue received from the support measures. The research results have substantiated the relevance of financing instruments, their terms and strategies in relation to their impact on the LCOE and competitiveness of wind PP. It has been found that financing of wind PP through the traditional financing instruments (simple shares and bank loans) makes use of venture capital and bonds coming even in the absence of any support. It has been estimated that strategies consisting of different proportions of hard and soft loans, bonds, own and venture capital result in the average LCOE of 5.1-5.7 EURct/kWh (2000 kW), when the expected electricity selling price is 5.4 EURct/kWh. The financing strategies with higher shares of equity could impact by around 6 % higher LCOE compared to the strategies encompassing higher shares of debt. However, seeking to motivate venture capitalists, bond holders or other new financiers entering the wind power sector, support measures (feed-in tariff or investment subsidy) are relevant in case of 250 kW wind PP. It has been estimated that under the unsupported financing strategies, the average LCOE of 250 kW wind PP will be 7.8-8.8 EURct/kWh, but it will reduce by around 50 % if feed-in tariff or 50 % investment subsidy is applied.

  6. Locational Prices in Capacity Subscription Market Considering Transmission Limitations

    Directory of Open Access Journals (Sweden)

    S. Babaeinejad Sarookolaee

    2013-06-01

    Full Text Available This study focuses on one of the most effective type of capacity markets named Capacity Subscription (CS market which is predicted to be widely used in the upcoming smart grids. Despite variant researches done about the mechanism and structure of capacity markets, their performances have been rarely tested in the presence of network constraints. Considering this deficiency, we tried to propose a new method to determine capacity prices in the network considering the transmission line flow limitations named Local capacity Prices (LP. This method is quite new and has not been tried before in any other similar researches. The philosophy of the proposed method is to determine capacity prices considering each consumer share of total peak demand. The first advantage of LP is that the consumers who benefit from the transmission facilities and are the responsible for transmission congestions, pay higher capacity prices than those whom their needed electricity is prepared locally. The second advantage of LP is that consumers connected to the same bus do not have to pay same capacity price due to their different shares of total peak demand. For more clarification, two other different methods named Branches Flow limit as a Global Limit (BFGL and Locational Capacity Prices (LCP are proposed and compared to the LP method in order to show LP method efficiency. The numerical results obtained from case studies show that the LP method follows more justice market procedure which results in more efficient capacity prices in comparison to BFGL and LCP methods.

  7. Economics of access versus ownership the costs and benefits of access to scholarly articles via interlibrary loan and journal subscriptions

    CERN Document Server

    Kingma, Bruce

    2013-01-01

    The Economics of Access Versus Ownership offers library professionals a model economic analysis of providing access to journal articles through interlibrary loan as compared to library subscriptions to the journals. This model enables library directors to do an economic analysis of interlibrary loan and collection development in their own libraries and to then make cost-efficient decisions about the use of these services.This practical book's analysis and conclusions are based on 1994/95 academic year research conducted by the State University of New York libraries at Albany, Binghamton, Buffa

  8. A comparative study of imbalance reduction strategies for virtual power plant operation

    International Nuclear Information System (INIS)

    Zapata, J.; Vandewalle, J.; D'haeseleer, W.

    2014-01-01

    The penetration of a large amount of distributed generation (DG) technologies with intermittent output, such as photovoltaic installations and wind turbines, yields an important challenge to the electric grid. It is believed that aggregating them with controllable technologies such as cogeneration devices (CHP) can help to balance fluctuations of renewable energy. This work evaluates the ability of a virtual power plant (VPP) to reduce the imbalance error of renewable generators. The study is undertaken in a VPP that consists of several cogeneration devices and photovoltaic (PV) installations. The virtual power plant operator bids electricity into the day-ahead market using the forecast for solar irradiation and for the thermal demand. During the actual day, the imbalance due to deviations between the forecasted electricity delivered and the real output has to be settled in the balancing market. Thus, in order to compensate these errors and possible economic drawbacks, the operation of the CHP is adjusted periodically in a so called reschedule. Two different rescheduling strategies are compared against a ‘reference scenario’ in which the imbalance error is settled in the market. The first one (‘forced strategy’) aims at reducing the imbalance error every time step regardless of the imbalance prices. The second (‘economic strategy’) considers the imbalance prices and takes only action if it is economically appropriate and thus intends to reduce the total operational cost. The results show that the rescheduling technique is able to reduce the imbalance error (up to 90% depending on the season and the strategy). Additionally, the total operational cost is estimated. However, the nowadays imbalance prices only lead to a minor financial advantage that is unlikely to motivate real life operators to perform a rescheduling strategy. - Highlights: • The VPP is dispatched by a day-ahead optimization followed by a rescheduling. • A forced rescheduling strategy

  9. THE STRATEGY OF EMPOWERMENT BASED ON ESQ POWER: A SOCIAL INNOVATION IN THE POVERTY OVERCOMING

    Directory of Open Access Journals (Sweden)

    Peribadi Peribadi

    2017-12-01

    Full Text Available This research aimed to develop an innovation of empowerment strategy on ESQ Power – Based. It was designed through a phenomenology deductive, a case study and the methodof research and development or the procedure of member check. The three of them were used eclectically in order to design an ideal formulation. The research findings indicated that the actors and actresses of poverty overcoming in Kendari City have not had the emotional intelligence and spiritual intelligence yet as ESQ Power. As a result, they were not optimal in performing their duties, roles and responsibilities. Therefore, the urgency of empowerment paradigm on ESQ Power – Based that has been formulated and validated by the skillful validator must be used in the future to increase the sense of responsibility of the actor network in overcoming the pauperization and poverty. Penelitian ini bertujuan untuk mengembangkan sebuah inovasi strategi pemberdayaan berbasis ESQ Power. Hal itu dirancang melalui deduksi fenomenologis, studi kasus serta metode penelitian dan pengembangan atau prosedur member check. Ketiganya digunakan secara eklektik untuk merancang formulasi ideal. Temuan penelitian menunjukkan bahwa aktor dan aktris penanggulangan kemiskinan di Kota Kendari belum memiliki kecerdasan emosional dan kecerdasan spiritual sebagai ESQ Power. Akibatnya, mereka tidak optimal dalam menjalankan tugas, peran dan tanggung jawabnya. Oleh karena itu, urgensi paradigma pemberdayaan berbasis ESQ Power yang telah dirumuskan dan divalidasi oleh validator ahli tersebut harus mulai digunakan ke depan untuk meningkatkan rasa tanggung jawab jaringan aktor dalam mengatasi pemiskinan dan kemiskinan.

  10. Strategy for improving instrumentation and control in operating nuclear power plants

    International Nuclear Information System (INIS)

    Abad Bassols, L.; Nino Perote, R.

    1996-01-01

    There are three basic reasons why nuclear power plants need to systematically upgrade their instrumentation and control equipment: Obsolete instrumentation and lack spares Little capacity of flexibility for extension Possibility of attaining better systems integration and improving systems-operations interface This article shows how to approach these issues using the following strategies: Use of distributed control systems and PLCs for control, signalling, command, communications, etc, in both nuclear and conventional applications Upgrading of process instrumentation equipment, sensors, transmitters, etc Upgrading of alarm-signalling systems In each group of equipment items consideration should be given to: Aspects regarding manufacturers-suppliers Effects on design, adaptation and documentation of operating plants Effects on the training and handling skills of operation and maintenance staff Strategy for incorporating the new system into the Plant with minimum impact on operation (Author)

  11. How Should We Assess the Fit of Rasch-Type Models? Approximating the Power of Goodness-of-Fit Statistics in Categorical Data Analysis

    Science.gov (United States)

    Maydeu-Olivares, Alberto; Montano, Rosa

    2013-01-01

    We investigate the performance of three statistics, R [subscript 1], R [subscript 2] (Glas in "Psychometrika" 53:525-546, 1988), and M [subscript 2] (Maydeu-Olivares & Joe in "J. Am. Stat. Assoc." 100:1009-1020, 2005, "Psychometrika" 71:713-732, 2006) to assess the overall fit of a one-parameter logistic model…

  12. POPS: the 60MW power converter for the PS accelerator: Control strategy and performances

    CERN Document Server

    Boattini, Fulvio; Skawinski, Gregory

    2015-01-01

    The main power supply of Proton-Synchrotron (PS) accelerator is one of the biggest at CERN. The old rotating machine system has been replaced with a new NPC based DC/DC power supply named POPS (Power system for PS main magnets) with capacitor banks as energy storage mean. POPS is in operation since February 2011. The operation of the PS accelerator requires a specific design of the control system with very high performance requirements in term of accuracy and precision. This paper describes the main lines of the control strategies analyzing the problems encountered and the solutions adopted. The performances of the converter are presented throughout the paper.

  13. The contracting risks of nuclear power engineering and the risk management strategies

    International Nuclear Information System (INIS)

    Ding Shuying

    2010-01-01

    With the trend of professional operation on the nuclear power engineering (thereafter using NPE for short) construction, the companies specialized on NPE whole-contracting are established one after the other, the mode of NPE whole-contracting has been wide adopted domestically. As people always concern for the safety of nuclear power, the risks exposed to NPE contractors are also concerned with the operator, the NPE corporations and the society. Therefore, it is very meaningful to analyze on the risks exposed to NPE contractors and the strategies they should take, for it not only determines whether the NPE construction will be finished on time, but also related to sustainable development of the NPE contracting corporations. The main content of this paper includes the analysis on the features and advantages of NPE whole contracting, the major NPE contracting risks, such as nuclear safety risks, strategic risks, market risks, legal risks, financial risks and operation risks, and the strategies to prevent or to control these risks. The paper focuses on identifying those business processes which risks may frequently take place, and how to manage them, illustrating practice cases to explain the theory, in order to make reference to NPE corporations. (author)

  14. Operation Strategy for a Power Grid Supplied by 100% Renewable Energy at a Cold Region in Japan

    Directory of Open Access Journals (Sweden)

    Jorge Morel

    2014-09-01

    Full Text Available This paper presents an operation strategy for a power system supplied from 100% renewable energy generation in Kitami City, a cold region in Japan. The main goal of this work is the complete elimination of the CO2 emissions of the city while keeping the power frequency within prescribed limits. Currently, the main energy related issue in Japan is the reduction of CO2 emissions without depending on nuclear generation. Also, there is a need for the adoption of distributed generation architecture in order to permit local autonomous operation of the system by the local generation of power. As a solution, this paper proposes a strategy to eliminate CO2 emissions that considers digital simulations using past hourly meteorological data and demand for one year. Results shows that Kitami City can be supplied entirely by renewable generation, reducing its CO2 emission to zero while keeping the quality of its power grid frequency within permitted limits.

  15. Conflict and Power Games in a Multinational Corporation : Sensegiving as a Strategy of Preservation

    NARCIS (Netherlands)

    Drori, Israel; Ellis, Shemuel

    In this paper, we seek to extend existing understandings of how sensegiving is associated with conflict and power games. We look specifically at sensegiving by managers that promotes strategies and actions geared toward preserving their positions against change. Formulating a conceptual framework

  16. Site Selection Strategy of Single-Frequency Tuned R-APF for Background Harmonic Voltage Damping in Power Systems

    DEFF Research Database (Denmark)

    Sun, Xiaofeng; Zeng, Jian; Chen, Zhe

    2013-01-01

    , and analyze the harmonic voltage propagation caused by the background harmonic voltage in power systems. Then, a new strategy is proposed for the site selection of resistive active power filter to damp the background harmonic voltage in power systems. Experiments have been performed to verify the theoretical......Series resonance between capacitance and line inductance may magnify background harmonic voltage and worsen the harmonic voltage distortion in power systems. To solve this problem, in this paper, the transmission line theory is used to set up the distributed parameter model of power system feeders...

  17. Large-scale integration of off-shore wind power and regulation strategies of cogeneration plants in the Danish electricity system

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    2005-01-01

    The article analyses how the amount of a small-scale CHP plants and heat pumps and the regulation strategies of these affect the quantity of off-shore wind power that may be integrated into Danish electricity supply......The article analyses how the amount of a small-scale CHP plants and heat pumps and the regulation strategies of these affect the quantity of off-shore wind power that may be integrated into Danish electricity supply...

  18. Systematic adaptation of data delivery

    Science.gov (United States)

    Bakken, David Edward

    2016-02-02

    This disclosure describes, in part, a system management component for use in a power grid data network to systematically adjust the quality of service of data published by publishers and subscribed to by subscribers within the network. In one implementation, subscribers may identify a desired data rate, a minimum acceptable data rate, desired latency, minimum acceptable latency and a priority for each subscription and the system management component may adjust the data rates in real-time to ensure that the power grid data network does not become overloaded and/or fail. In one example, subscriptions with lower priorities may have their quality of service adjusted before subscriptions with higher priorities. In each instance, the quality of service may be maintained, even if reduced, to meet or exceed the minimum acceptable quality of service for the subscription.

  19. Nurses' perception of the strategies to gaining professional power: A qualitative study.

    Science.gov (United States)

    Sepasi, Rana Rezai; Borhani, Fariba; Abbaszadeh, Abbas

    2017-07-01

    Power in nursing is a broad concept that has a determining effect on the achievement of professional goals. Gaining power is essential for promoting the roles of nurses, improving their professional image and the consistent improvement of healthcare systems. This study was conducted to identify and clarify strategies for gaining power in the nursing profession through the experiences of Iranian nurses. The present qualitative grounded theory study was conducted on fifteen participants selected through purposive sampling. Data were collected through individual, in-depth, semi-structured interviews. The data obtained were analyzed using the guidelines provided by Corbin and Strauss, (2008 edition). This study was carried out in Qazvin city of Iran and lasted fourteen months (2015-2016). The analysis of the data were classified under the main theme of gaining human-professional power based on individual and organizational capacities, divided into four main categories, including respecting human values and ethical principles (with two subcategories, keeping the human symbols of power and commitment to moral obligations of power), promoting professional interactions (with two subcategories, paying attention to intraprofessional communication and paying attention to interprofessional communication), attempting professional endurance (with two subcategories, raising self-confidence and having professional commitment), and valuing potential capacities (with two subcategories, regard for individual capacities and regard for organizational capacities). The findings obtained suggest that success in gaining power in nursing, requires a cumulative focus on human, ethical, professional, individual and organizational capacities.

  20. Maximum power extraction under different vector-control schemes and grid-synchronization strategy of a wind-driven Brushless Doubly-Fed Reluctance Generator.

    Science.gov (United States)

    Mousa, Mohamed G; Allam, S M; Rashad, Essam M

    2018-01-01

    This paper proposes an advanced strategy to synchronize the wind-driven Brushless Doubly-Fed Reluctance Generator (BDFRG) to the grid-side terminals. The proposed strategy depends mainly upon determining the electrical angle of the grid voltage, θ v and using the same transformation matrix of both the power winding and grid sides to ensure that the generated power-winding voltage has the same phase-sequence of the grid-side voltage. On the other hand, the paper proposes a vector-control (power-winding flux orientation) technique for maximum wind-power extraction under two schemes summarized as; unity power-factor operation and minimum converter-current. Moreover, a soft-starting method is suggested to avoid the employed converter over-current. The first control scheme is achieved by adjusting the command power-winding reactive power at zero for a unity power-factor operation. However, the second scheme depends on setting the command d-axis control-winding current at zero to maximize the ratio of the generator electromagnetic-torque per the converter current. This enables the system to get a certain command torque under minimum converter current. A sample of the obtained simulation and experimental results is presented to check the effectiveness of the proposed control strategies. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  1. DESIGN OF THE THREE-LEVEL MULTICRITERIAL STRATEGY OF HYBRID MARINE POWER PLANT CONTROL FOR A COMBINED PROPULSION COMPLEX

    Directory of Open Access Journals (Sweden)

    V.V. Budashko

    2017-04-01

    Full Text Available Purpose. Efficiency of hybrid ships power plants (SPP combined propulsion complexes (CPC by various criteria for energy management systems strategies. Methodology. Based on the classification system topologies SPP CPC for mechanical, electrical and hybrid types of motors schematic diagrams of management strategies for the criterion of minimum power consumption are defined. Changing the technical component of the traditional approach to building hybrid ships electric power systems (SEPS SPP CPC the principle of modifying the structure of SEPS is applied with the integration of additional static alternative power source as dynamic reserve, which allowed to meet modern requirements for energy efficiency, levels of vibration, noise and degradation effects produced to SPP CPC, in all areas of the energy for the transfer of power from energy to propellers. Modeling of power transmission of energy to propellers in MatLab/Simulink is conducted, using blocks of optimization library and definition of identity markers. Results. Major advantages and disadvantages SPP CPC depending on the topology of energy distribution systems are determined. According to the chosen structure system electricity characteristics were obtained in the process of power transmission SPP CPC and power systems and their control strategies in terms of increased efficiency and eliminate these drawbacks. And finally, mathematical apparatus for research in terms of the development of methods for designing and managing SPP hybrid CPC to reduced fuel consumption, emissions into the environment and improving maintainability, flexibility and comfort level are improved. Originality. The methodology for improving SPP CPC implementation by developing methods of identification markers mutually influencing processes in SPP CPC and the development of implementing these methods of settlement and information systems. Practical value. The method enables iterative optimization parameters SPP CPC, it

  2. Fusion power economy of scale

    International Nuclear Information System (INIS)

    Dolan, T.J.

    1993-01-01

    In the next 50 yr, the world will need to develop hundreds of gigawatts of non-fossil-fuel energy sources for production of electricity and fuels. Nuclear fusion can probably provide much of the required energy economically, if large single-unit power plants are acceptable. Large power plants are more common than most people realize: There are already many multiple-unit power plants producing 2 to 5 GW(electric) at a single site. The cost of electricity (COE) from fusion energy is predicted to scale as COE ∼ COE 0 (P/P 0 ) -n , where P is the electrical power, the subscript zero denotes reference values, and the exponent n ∼ 0.36 to 0.7 in various designs. The validity ranges of these scalings are limited and need to be extended by future work. The fusion power economy of scale derives from four interrelated effects: improved operations and maintenance costs; scaling of equipment unit costs; a geometric effect that increases the mass power density; and reduction of the recirculating power fraction. Increased plasma size also relaxes the required confinement parameters: For the same neutron wall loading, larger tokamaks can use lower magnetic fields. Fossil-fuel power plants have a weaker economy of scale than fusion because the fuel costs constitute much of their COE. Solar and wind power plants consist of many small units, so they have little economy of scale. Fission power plants have a strong economy of scale but are unable to exploit it because the maximum unit size is limited by safety concerns. Large, steady-state fusion reactors generating 3 to 6 GW(electric) may be able to produce electricity for 4 to 5 cents/kW·h, which would be competitive with other future energy sources. 38 refs., 6 figs., 6 tabs

  3. Responsibility Towards The Customers Of Subscription-Based Software Solutions In The Context Of Using The Cloud Computing Technology

    Directory of Open Access Journals (Sweden)

    Bogdan Ștefan Ionescu

    2003-12-01

    Full Text Available The continuously transformation of the contemporary society and IT environment circumscribed its informational has led to the emergence of the cloud computing technology that provides the access to infrastructure and subscription-based software services, as well. In the context of a growing number of service providers with of cloud software, the paper aims to identify the perception of some current or potential users of the cloud solution, selected from among students enrolled in the accounting (professional or research master programs with the profile organized by the Bucharest University of Economic Studies, in terms of their expectations for cloud services, as well as the extent to which the SaaS providers are responsible for the provided services.

  4. 78 FR 20313 - American Municipal Power, Inc.; Michigan Public Power Agency; Notice of Filing

    Science.gov (United States)

    2013-04-04

    ... requirement for reactive supply and voltage control from generation or other sources service (Fremont Energy... Commission's Public Reference Room in Washington, DC. There is an ``eSubscription'' link on the Web site that...

  5. Wind power integration into the automatic generation control of power systems with large-scale wind power

    Directory of Open Access Journals (Sweden)

    Abdul Basit

    2014-10-01

    Full Text Available Transmission system operators have an increased interest in the active participation of wind power plants (WPP in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different possible future scenarios, when wind power production in the power system is high and conventional production from CHPs is at a minimum level. The investigation results of the proposed control strategy have shown that the WPPs can actively help the AGC, and reduce the real-time power imbalance in the power system, by down regulating their production when CHPs are unable to provide the required response.

  6. Wind power integration into the automatic generation control of power systems with large-scale wind power

    DEFF Research Database (Denmark)

    Basit, Abdul; Hansen, Anca Daniela; Altin, Müfit

    2014-01-01

    Transmission system operators have an increased interest in the active participation of wind power plants (WPP) in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC......) of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs) and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described...... and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different...

  7. Energy strategy 2025. Perspectives towards 2025 and introductory action plan for the future power infrastructure

    International Nuclear Information System (INIS)

    2005-01-01

    The Danish Government's long-term energy strategy follows up on the political agreement of 29 March 2004. The energy strategy is a coherent formulation of the Government's long-term energy policy. The pivotal point for the energy strategy is liberalized energy markets and market based tools for obtaining goals such as efficiency, security of supply and environment. The focus is increasingly on the substantial business potential within development of new and more efficient energy technology, in which Denmark takes up several globally strong positions. Furthermore, transportation energy consumption has been included directly in an energy strategy for the first time. At the same time as the energy strategy is presented, a summarizing background report from the Danish Energy Agency with facts, analyses and evaluations is published, as well as a report from energinet.dk that summarizes the system responsibilities' input to that part of the energy strategy that deals with power infrastructure. (BA)

  8. Power allocation strategies to minimize energy consumption in wireless body area networks.

    Science.gov (United States)

    Kailas, Aravind

    2011-01-01

    The wide scale deployment of wireless body area networks (WBANs) hinges on designing energy efficient communication protocols to support the reliable communication as well as to prolong the network lifetime. Cooperative communications, a relatively new idea in wireless communications, offers the benefits of multi-antenna systems, thereby improving the link reliability and boosting energy efficiency. In this short paper, the advantages of resorting to cooperative communications for WBANs in terms of minimized energy consumption are investigated. Adopting an energy model that encompasses energy consumptions in the transmitter and receiver circuits, and transmitting energy per bit, it is seen that cooperative transmission can improve energy efficiency of the wireless network. In particular, the problem of optimal power allocation is studied with the constraint of targeted outage probability. Two strategies of power allocation are considered: power allocation with and without posture state information. Using analysis and simulation-based results, two key points are demonstrated: (i) allocating power to the on-body sensors making use of the posture information can reduce the total energy consumption of the WBAN; and (ii) when the channel condition is good, it is better to recruit less relays for cooperation to enhance energy efficiency.

  9. The active control strategy on the output power for photovoltaic-storage systems based on extended PQ-QV-PV Node

    Science.gov (United States)

    Xu, Chen; Zhou, Bao-Rong; Zhai, Jian-Wei; Zhang, Yong-Jun; Yi, Ying-Qi

    2017-05-01

    In order to solve the problem of voltage exceeding specified limits and improve the penetration of photovoltaic in distribution network, we can make full use of the active power regulation ability of energy storage(ES) and the reactive power regulation ability of grid-connected photovoltaic inverter to provide support of active power and reactive power for distribution network. A strategy of actively controlling the output power for photovoltaic-storage system based on extended PQ-QV-PV node by analyzing the voltage regulating mechanism of point of commom coupling(PCC) of photovoltaic with energy storage(PVES) by controlling photovoltaic inverter and energy storage. The strategy set a small wave range of voltage to every photovoltaic by making the type of PCC convert among PQ, PV and QV. The simulation results indicate that the active control method can provide a better solution to the problem of voltage exceeding specified limits when photovoltaic is connectted to electric distribution network.

  10. PI and Fuzzy Control Strategies for High Voltage Output DC-DC Boost Power Converter - Hardware Implementation and Analysis

    DEFF Research Database (Denmark)

    Padmanaban, Sanjeevi Kumar; Blaabjerg, Frede; Siano, Pierluigi

    2016-01-01

    This paper presents the control strategies by Proportional-Integral (P-I) and Fuzzy Logic (FL) for a DC-DC boost power converter for high output voltage configuration. Standard DC-DC converters are traditionally used for high voltage direct current (HVDC) power transmission systems. But, lack its...... converter with inbuilt voltage-lift technique and overcome the aforementioned deficiencies. Further, the control strategy is adapted based on proportional-integral (P-I) and fuzzy logic, closed-loop controller to regulate the outputs and ensure the performances. Complete hardware prototype of EHV converter...... performances in terms of efficiency, reduced transfer gain and increased cost with sensor units. Moreover, the internal self-parasitic components reduce the output voltage and efficiency of classical high voltage converters (HVC). This investigation focused on extra high-voltage (EHV) DC-DC boost power...

  11. Nuclear power strategy: requirements for technology

    International Nuclear Information System (INIS)

    Orlov, V.V.; Rachkov, V.I.

    2001-01-01

    The possible role of nuclear power in sustainable development demands answers to at least three questions: Is large-scale nuclear power essential to future development? - Is it feasible to have modern nuclear power transformed for large-scale deployment? - When will large-scale nuclear power be practically needed? The questions are analysed with the requirements to be fulfilled concerning present-day technologies

  12. About the development strategies of power plant in energy market

    Science.gov (United States)

    Duinea, Adelaida Mihaela

    2017-12-01

    The paper aims at identifying and assessing the revenues and costs incurred by various modernization and modernization-development strategies for a power plant in order to optimize the electric and thermal energy are produced and to conduct a sensitivity analysis of the main performance indicators. The Romanian energy system and the energy market have gone a long transition way, from the vertically integrated model, the responsibility for the delivery of the electricity comes exclusively to a state monopoly, to a decentralized system, characterized by the decentralization of production and transport, respectively distribution activities. Romania chose the liberal market model where the relations between the actors in the market - producers and suppliers free to make sales and purchase transactions for electrical energy - are mostly governed by contracts, which may be either bilaterally negotiated or are already regulated. Therefore, the importance of understanding the development trend of the Romanian energy market lies in its economic effects upon the solutions which could be adopted for the evolution of the cogeneration power plant in question.

  13. New products from the power merchant to customer with time measurements and load management

    International Nuclear Information System (INIS)

    Solem, Gerd; Doorman, Gerard; Grande, Ove S.

    2003-01-01

    The main aim is to develop products from the power merchants that improve the consumer flexibility. For the development of the products the basis is that the consumption is measured by hours and that a connection to a load management scheme is present. Calculations for four products are made where the risk exposure is different for the customer and the supplier. The four products are ''Spot price with mark-up'', ''The combination of constant price and spot price'', ''Constant price with disconnection'' and ''Effect subscription''. The customers are exposed to the spot price in the first two products and may through disconnection reduce the costs by adapting to the market signals. Remote disconnection of parts of the consumption may be offered as a service jointly by the network companies and the power suppliers through a two-way communication but it is not realistic that the customers may pay much for this. ''Spot price with mark-up'' implies that the customer carries the entire risk while constant price may place considerable risk at the power supplier by long high consumption combined with high spot prices. '' Constant price with disconnection'' gives the power supplier the possibilities of reducing the risks. A disconnection possibility that is committing to the customers may be part of the product specification. The customers may be offered a discount calculated out from the costs for alternative price securing. Also '' Effect subscription'' reduces the merchant risks considerably at the disconnection of the consumption. The ''combined product of constant and spot price'' may be interesting from the supplier's viewpoint due to considerable risk reductions compared to solely using the constant price. The product gives the customers a guaranteed price for a part of the product and has an additional possibility of adapting the consumption to the market signals. The network company routines for handling of the hour values are a large challenge. It is important to

  14. Power control strategy of a photovoltaic power plant for microgrid applications

    Energy Technology Data Exchange (ETDEWEB)

    Li, Peng [Ecole Centrale de Lille, Cite Scientifique, Villeneuve d' Ascq (FR). Laboratoire d' Electrotechnique et d' Electronique de Puissance de Lille (L2EP); Ecole Nationale Superieure d' Arts et Metiers, Lille (FR). Laboratoire d' Electrotechnique et d' Electronique de Puissance de Lille (L2EP); Francois, Bruno [Ecole Centrale de Lille, Cite Scientifique, Villeneuve d' Ascq (FR). Laboratoire d' Electrotechnique et d' Electronique de Puissance de Lille (L2EP); Degobert, Philippe [Ecole Nationale Superieure d' Arts et Metiers, Lille (FR). Laboratoire d' Electrotechnique et d' Electronique de Puissance de Lille (L2EP); Robyns, Benoit [Hautes Etudes d' Ingenieur, Lille (FR). Laboratoire d' Electrotechnique et d' Electronique de Puissance de Lille (L2EP)

    2008-07-01

    Photovoltaic power plants operates currently maximal power point tracking (MPPT). For microgrid applications, however, a PV power plant can not operate in the MPPT mode in all conditions. When a microgrid is islanded from the grid with few loads, a limitation of the produced power by PV plants is required and prescribed by the Distribution System Operator. This paper proposes a power control technique integrated into a dynamic model of a PV power plant by using equivalent continuous models of power electronic converters. The power limitation mode of the PV is performed by applying the correct PV terminal voltage, which corresponds to the prescribed power reference. The proposed global model is validated by simulations with the help of Matlab-Simulink trademark. (orig.)

  15. Use of decision trees for evaluating severe accident management strategies in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Jae, Moosung [Hanyang Univ., Seoul (Korea, Republic of). Dept. of Nuclerar Engineering; Lee, Yongjin; Jerng, Dong Wook [Chung-Ang Univ., Seoul (Korea, Republic of). School of Energy Systems Engineering

    2016-07-15

    Accident management strategies are defined to innovative actions taken by plant operators to prevent core damage or to maintain the sound containment integrity. Such actions minimize the chance of offsite radioactive substance leaks that lead to and intensify core damage under power plant accident conditions. Accident management extends the concept of Defense in Depth against core meltdown accidents. In pressurized water reactors, emergency operating procedures are performed to extend the core cooling time. The effectiveness of Severe Accident Management Guidance (SAMG) became an important issue. Severe accident management strategies are evaluated with a methodology utilizing the decision tree technique.

  16. Development of strategies for communication with public on nuclear power

    International Nuclear Information System (INIS)

    Narayanan, K.K.

    2012-01-01

    Nuclear industry, as a whole, has so often communicated a lack of confidence in the public. There are historical reasons for this, including the fact that the tremendous power of atom was introduced to mankind in a most, destructive way by exploding two atomic devices at Hiroshima and Nagasaki. Other reasons are the secrecy rooted in its activities, problems in communicating scientific concepts with general public and use of jargons, which on occasions resulted in misinterpretation by the public. The resulting lack of public confidence is a major road-block in its development in many countries, including India. So it is essential to establish a trust between nuclear industry and general public. To achieve this, effective communication with public on issues related to nuclear power is imperative. The important components of this strategy are: 1. The goals 2. The message 3. The communicators 4.The audience 5.The tools. These components are briefly discussed below. The Goals: What are the goals to be achieved? The aim should be building awareness, understanding and public support for the nuclear power program across the country. If this is achieved half the battle is won. The Message: What are your messages to the public? At the outset you should be very clear about your message, believe it, and make it believable to your audience. The message should be positive, clear and simple. It should stress the inevitability of nuclear power in the energy scenario and the overall development of the country. The communicators: Who are the communicators? Identify, and prepare the communicators of the message. Put a human face on them. Make sure that those who deliver the message must really believe in the message. Third party communicators have a higher level of credibility, because they are not from the nuclear industry. It is vital that communicators be skilled in the art of listening to the audience - a two-way dialogue has to be maintained. Special training is essential for

  17. Hybrid wind power balance control strategy using thermal power, hydro power and flow batteries

    OpenAIRE

    Gelažanskas, Linas; Baranauskas, Audrius; Gamage, Kelum A.A.; Ažubalis, Mindaugas

    2016-01-01

    The increased number of renewable power plants pose threat to power system balance. Their intermittent nature makes it very difficult to predict power output, thus either additional reserve power plants or new storage and control technologies are required. Traditional spinning reserve cannot fully compensate sudden changes in renewable energy power generation. Using new storage technologies such as flow batteries, it is feasible to balance the variations in power and voltage within very short...

  18. Development of Flexible Active Power Control Strategies for Grid-Connected Photovoltaic Inverters by Modifying MPPT Algorithms

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

    2017-01-01

    As the penetration level of grid-connected PV systems increases, more advanced control functionality is demanded. In order to ensure smooth and friendly grid integration as well as enable more PV installations, the power generated by PV systems needs to be flexible and capable of: 1) limiting...... strategies for grid-connected PV inverters by modifying maximum power point tracking algorithms, where the PV power is regulated by changing the operating point of the PV system. In this way, no extra equipment is needed, being a cost-effective solution. Experiments on a 3-kW grid-connected PV system have...... the maximum feed-in power, 2) ensuring a smooth change rate, and 3) providing a power reserve. Besides, such flexible power control functionalities have to be achieved in a cost-effective way in order to ensure the competitiveness of solar energy. Therefore, this paper explores flexible active power control...

  19. Assessment of off-design performance of a small-scale combined cooling and power system using an alternative operating strategy for gas turbine

    International Nuclear Information System (INIS)

    Han, Wei; Chen, Qiang; Lin, Ru-mou; Jin, Hong-guang

    2015-01-01

    Highlights: • We develop an off-design model for a CCP system driven by gas turbine. • An alternative operating strategy is proposed to improve the system performance. • Off-design performance of the combined cooling and power system (CCP) is enhanced. • Effects of both the different operating strategy are analyzed and compared. • Performance enhancement mechanism of the proposed operating strategy is presented. - Abstract: A small-scale combined cooling and power (CCP) system usually serves district air conditioning apart from power generation purposes. The typical system consists of a gas turbine and an exhaust gas-fired absorption refrigerator. The surplus heat of the gas turbine is recovered to generate cooling energy. In this way, the CCP system has a high overall efficiency at the design point. However, the CCP system usually runs under off-design conditions because the users’ demand varies frequently. The operating strategy of the gas turbine will affect the thermodynamic performance of itself and the entire CCP system. The operating strategies for gas turbines include the reducing turbine inlet temperature (TIT) and the compressor inlet air throttling (IAT). A CCP system, consisting of an OPRA gas turbine and a double effects absorption refrigerator, is investigated to identify the effects of different operating strategies. The CCP system is simulated based on the partial-load model of gas turbine and absorption refrigerator. The off-design performance of the CCP system is compared under different operating strategies. The results show that the IAT strategy is the better one. At 50% rated power output of the gas turbine, the IAT operating strategy can increase overall system efficiency by 10% compared with the TIT strategy. In general, the IAT operating strategy is suited for other gas turbines. However, the benefits of IAT should be investigated in the future, when different gas turbine is adopted. This study may provide a new operating

  20. Adaptive control strategy for ECRH negative high-voltage power supply based on CMAC neural network

    International Nuclear Information System (INIS)

    Luo Xiaoping; Du Pengying; Du Shaowu

    2011-01-01

    In order to solve the problem that the negative high-voltage power supply in an electron cyclotron resonance heating (ECRH) system can not satisfy the requirements because of the nonlinearity and sensitivity, the direct inverse model control strategy was proposed by using cerebellar model articulation controller(CMAC) for better control, and experiments were carried out to study the system performances with CMAC tracing dynamic signals. The results show that this strategy is strong in self-learning and self-adaptation and easy to be realized. (authors)

  1. Intelligent Power Management of hybrid Wind/ Fuel Cell/ Energy Storage Power Generation System

    OpenAIRE

    A. Hajizadeh; F. Hassanzadeh

    2013-01-01

    This paper presents an intelligent power management strategy for hybrid wind/ fuel cell/ energy storage power generation system. The dynamic models of wind turbine, fuel cell and energy storage have been used for simulation of hybrid power system. In order to design power flow control strategy, a fuzzy logic control has been implemented to manage the power between power sources. The optimal operation of the hybrid power system is a main goal of designing power management strategy. The hybrid ...

  2. Suscripción de revistas en línea en la Argentina, 2007 On line journals subscription in Argentina, 2007

    Directory of Open Access Journals (Sweden)

    Susana Romanos de Tiratel

    2011-12-01

    Full Text Available El artículo presenta los resultados de una investigación orientada a describir aspectos del proceso de suscripción de revistas en línea en la Argentina. Entre abril y setiembre del año 2007 se aplicó una encuesta vía correo electrónico a bibliotecas especializadas y universitarias argentinas para indagar acerca de los actores involucrados en la identificación, evaluación y selección de títulos, en la negociación y firma de las licencias, las modalidades de suscripción y los tipos de recursos suscriptos por esas unidades de información. Se observó una alta participación de los bibliotecarios en todo el proceso que disminuía en la etapa de negociación y firma de los acuerdos de licencia donde los directores institucionales y los administradores tenían un rol más destacado.This paper presents the findings of an investigation aimed at describing aspects of the process of online journals subscription in Argentina. From April to September of 2007 a survey was conducted via electronic mail to special and academic libraries to inquire about Argentine actors involved in the identification, evaluation, and selection of titles, in the negotiation and signing of the licences, the subscription methods, and type of resources subscribed for those information units. There was a high participation of librarians in the process that decreased in the stage of negotiating and signing the licencing agreements where institutional managers and administrators had a more prominent role.

  3. Powering Kuwait into the 21. Century. Adopting a Sustainable Strategy

    International Nuclear Information System (INIS)

    Boncourt, Maite de

    2012-09-01

    of the new buildings. New refining activities will also be energy intensive. This in turn could increase the number of migrant workers and consequently the population would grow faster than on a business as usual trend. Consumption forecasts are well below neighbour countries estimates, and this report is also conservative compared to official forecasts data. Last but not least, other sectors such as transport or petrochemicals will need an increasing amount of oil. The domestic oil consumption will in any case in increase in the years to come. This report concludes that Kuwait's power sector fuel mix and consumption path is not sustainable. In the short term, rising power consumption could lead to shortages in power capacity. Due to this unexpected power demand, capacity utilisation has been almost complete. Successive black outs in the last years led to the installation of expensive to run emergency gas fired turbines. In the no change scenario, growing power consumption would lead to decrease in oil export revenues, representing 91.6% of the state 2010/2011 budget. This would have a very negative impact on the overall economy, which is not substantially diversified yet. Costs would on the other hand increase as more power capacity would need to be installed, a larger amount of increasingly expensive fuel will have to be purchased and the state power subsidies bill, already amounting to $9 billion, will explode. While rising oil prices could compensate to a certain extent, and wait and see strategy risks locking Kuwait into a non-viable path

  4. The state of the art in Japan's telecommunications energy systems - Strategy for Total Power Management -

    Energy Technology Data Exchange (ETDEWEB)

    Muroyama, Seiichi [NTT Power and Building Facilities Inc., Midori-cho, Musashino-shi, Tokyo (Japan)

    2000-07-01

    The ''strategy for total power management (STPM)'' was developed for managing problems in relation to energy for multimedia services in a comprehensive manner from the viewpoints of risk, cost, and environment. To provide integrated services based on STPM, a DC power supply system, a highly reliable UPS, and a co-generation system have been developed. (orig.)

  5. Advanced Control Strategy of DFIG Wind Turbines for Power System Fault Ride Through

    DEFF Research Database (Denmark)

    Yang, Lihui; Xu, Zhao; Ostergaard, Jacob

    2012-01-01

    , the rotor side controller can convert the imbalanced power into the kinetic energy of the WT by increasing its rotor speed, when a low voltage due to a grid fault occurs at, e.g., the point of common coupling (PCC). The proposed grid side control scheme introduces a compensation term reflecting...... the oscillations in the stator and rotor currents and the DC bus voltage. The effectiveness of the proposed control strategy has been demonstrated through various simulation cases. Compared with conventional crowbar protection, the proposed control method can not only improve the LVRT capability of the DFIG WT......, but also help maintaining continuous active and reactive power control of the DFIG during the grid faults....

  6. A three-phase to three-phase series-resonant power converter with optimal input current waveforms, Part I: control strategy

    NARCIS (Netherlands)

    Huisman, H.

    1988-01-01

    A control strategy for multiphase-input multiphase-output AC to AC series-resonant (SR) power converters is presented. After reviewing some basics in SR power converters, a hierarchy of control mechanisms is presented, together with their respective theoretical backgrounds and practical limitations.

  7. IT substitution for energy leads to a resilient structure for a survival strategy of Japan's electric power industry

    International Nuclear Information System (INIS)

    Watanabe, Chihiro; Kishioka, Miharu; Carvajal, C.A.

    2005-01-01

    The dramatic surge in information technology (IT) around the world, and an evolving global economy, are subjecting firms to megacompetition. This is the case, particularly in Japan's electric power industry, where the power rate is one of the highest in the world; hence it is noted that Japan's industry has lost its price competitiveness in the world market, resulting in stagnation of production, hence leading to stagnation in power demand. In addition, an increase in trends of customer's preferences and the variety of participants in the power supply race, have put electric power companies at the mercy of customers with alternative supply sources. Given that uncertainty with respect to energy security, as well as power generation and distribution systems safety increases, as strongly cautioned by the recent blackout in the US and Canada, a dramatic conversion of existing strategies would be indispensable for electric power companies. A conversion from a high-demand-elasticity dependent, supply structure to a resilient structure is required. While the former aims at constructing a high-demand-elasticity supply structure, based on the myth of high growth of demand, the latter aims at maintaining profit, while minimizing the elasticities of factors with high uncertainty, such as energy resources and costly capital investment linked to a fluctuating power demand. This paper demonstrates the significance of IT substitution for energy through consortia structure, thereby utilizing IT spillover and leading to resilience and leveraging consortia structure as Japan's electric power industry survival strategy. An empirical analysis using Japan's nine leading electric power companies over the last quarter century has been conducted

  8. Safety strategy and safety analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Franzen, L.F.

    1976-01-01

    The safety strategy for nuclear power plants is characterized by the fact that the high level of safety was attained not as a result of experience, but on the basis of preventive accident analyses and the finding derived from such analyses. Although, in these accident analyses, the deterministic approach is predominant, it is supplemented by reliability analyses. The accidents analyzed in nuclear licensing procedures cover a wide spectrum from minor incidents to the design basis accidents which determine the design of the safety devices. The initial and boundary conditions, which are essentail for accident analyses, and the determination of the loads occurring in various states during regular operation and in accidents flow into the design of the individual systems and components. The inevitable residual risk and its origins are discussed. (orig.) [de

  9. A matrix game model for analyzing FTR bidding strategies in deregulated electric power markets

    International Nuclear Information System (INIS)

    Das, Tapas K.; Rocha, Patricio; Babayigit, Cihan

    2010-01-01

    Suppliers in deregulated electric power markets compete for financial transmission rights (FTRs) to hedge against congestion charges. The system operator receives the bids for FTRs submitted by the suppliers and develops an allocation strategy by solving an optimization model. Each FTR bid is defined by a path, a quantity indicating the amount of FTRs the supplier is bidding for in that path, and the price that the supplier is willing to pay for each FTR. The FTR revenue is calculated only after the electricity market has been cleared by computing the differences in the LMPs at the pair of nodes that connect each path. Thus, suppliers rely on forecasts of locational marginal prices (LMPs) to develop their FTR bids. In this paper, we present a game theoretic modeling approach to develop FTR bidding strategies for power suppliers assuming that they have forecasts of LMPs. The game theoretic model considers multiple participants as well as network contingencies. We apply the game theoretic model on a sample network to assess impacts of variations of bid and network parameters on the FTR market outcome. (author)

  10. Application of Q-learning with temperature variation for bidding strategies in market based power systems

    International Nuclear Information System (INIS)

    Naghibi-Sistani, M.B.; Akbarzadeh-Tootoonchi, M.R.; Javidi-Dashte Bayaz, M.H.; Rajabi-Mashhadi, H.

    2006-01-01

    The electric power industry is confronted with restructuring in which the operation scheduling is going to be decided based on a competitive market. In this new arrangement, bidding strategy has become a major issue. Participants in this deregulated energy market place may be able to compete better by choosing a suitable bidding strategy for trading electricity. Different classical methods for decision making in the uncertain environment of the market can be applied to select a suitable strategy. Most of these methods, such as game theory, that insure reaching the best solution for all market participants, require a lot of information about the other market players and the market. However, in the real market place only a little information, such as the spot price, is available for all participants. In this paper, a modified reinforcement learning based on temperature variation has been first proposed and then applied to determine the optimal strategy for a power supplier in the electricity market. A Pool-Co model has been considered here, and the simulation results are shown to be the same as those of standard game theory. Adaptation of the method in the presence of parameter variation has been verified as well. The main advantage of the proposed method is that no information about other participants is required. Furthermore, our investigation shows that even if all participants use this method, they will stay in Nash equilibrium. (author)

  11. Development of master-slave energy management strategy based on fuzzy logic hysteresis state machine and differential power processing compensation for a PEMFC-LIB-SC hybrid tramway

    International Nuclear Information System (INIS)

    Peng, Fei; Zhao, Yuanzhe; Li, Xiaopeng; Liu, Zhixiang; Chen, Weirong; Liu, Yang; Zhou, Donghua

    2017-01-01

    Highlights: •A power system model for the PEMFC based commercial hybrid tramway was established. •An energy management strategy based on master FuHSM and slave DPPC was proposed. •The optimal OER operation of PEMFC subsystem was achieved. •The real-time EMS based HCM optimization was achieved. •The influence on system fuel economy and PEMFC performance degradation was verified. -- Abstract: A hybrid power system configuration based on proton exchange membrane fuel cell (PEMFC), lion-lithium battery (LIB) and supercapacitor (SC) was designed without grid connection for the hybrid tramway. To adapt to the rapid load power change and achieve higher fuel efficiency and optimal oxygen excess ratio (OER) operation of the PEMFC power subsystem, a master-slave energy management strategy based on fuzzy logic hysteresis state machine (FuHSM) and differential power processing compensation (DPPC) was proposed for the hybrid tramway, effectively taking into consideration of the dynamic response and optimum OER tracing of the integrated PEMFC subsystem. The master FuHSM controller was utilized to grantee the optimal power coordination of the multiple power sources and the slave DPPC controller was responsible for further compensating the load power demand to enhance the dynamic performance and bus voltage stability. Furthermore, the equivalent H 2 consumption minimization optimization considering characteristics of the proposed energy management strategy was realized by means of EIA-PSO algorithm to further improve the fuel economy of the overall hybrid power system. The results demonstrate that the proposed energy management strategy can guarantee the stability of the hybrid power system throughout the driving cycle. In addition, more efficient power coordination dynamics among the PEMFC, LIB and SC subsystems could be achieved without additional performance degradation of the integrated PEMFC subsystem, and the results of the comparisons with other control strategies

  12. Development of Abnormal Operating Strategies for Loss of Ultimate Heat Sink (LOUHS) at Shutdown Mode in Westinghouse Type Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Duk-Joo; Lee, Seung-Chan; Sung, Je-Joong; Ha, Sang Jun [KHNP CRI, Daejeon (Korea, Republic of); Hwang, Su-Hyun [FNC Tech. Co., Yongin (Korea, Republic of)

    2016-10-15

    Loss of all AC power is classified as one of multiple failure accident by regulatory guide of Korean accident management program. Therefore we need develop strategies for the abnormal operating procedure both of power operating and shutdown mode. This paper developed abnormal operating guideline for loss of all AC power by analysis of accident scenario in pressurized water reactor. This paper analyzed the extended SBO in shutdown operating mode and developed the operating strategy of the abnormal operation procedure. Operator action for the emergency are not required to take in 500 minutes and 60 minutes in intact and opened RCS state respectively.

  13. Prospects and strategy for large scale utility applications of photovoltaic power systems

    International Nuclear Information System (INIS)

    Vigotti, R.; Lysen, E.; Cole, A.

    1996-01-01

    The status and prospects of photovoltaic (PV) power systems are reviewed. The market diffusion strategy for the application of PV systems by utilities is described, and the mission, objectives and thoughts of the collaboration programme launched among 18 industrialized countries under the framework of the International Energy Agency are highly with particular reference to technology transfer to developing countries. Future sales of PV systems are expected to grow in the short and medium term mainly in the sector of isolated systems. (R.P.)

  14. Study on Stochastic Optimal Electric Power Procurement Strategies with Uncertain Market Prices

    Science.gov (United States)

    Sakchai, Siripatanakulkhajorn; Saisho, Yuichi; Fujii, Yasumasa; Yamaji, Kenji

    The player in deregulated electricity markets can be categorized into three groups of GENCO (Generator Companies), TRNASCO (Transmission Companies), DISCO (Distribution Companies). This research focuses on the role of Distribution Companies, which purchase electricity from market at randomly fluctuating prices, and provide it to their customers at given fixed prices. Therefore Distribution companies have to take the risk stemming from price fluctuation of electricity instead of the customers. This entails the necessity to develop a certain method to make an optimal strategy for electricity procurement. In such a circumstance, this research has the purpose for proposing the mathematical method based on stochastic dynamic programming to evaluate the value of a long-term bilateral contract of electricity trade, and also a project of combination of the bilateral contract and power generation with their own generators for procuring electric power in deregulated market.

  15. Establishment of KAERI Strategy and Organization for Fusion Power Technology Research

    International Nuclear Information System (INIS)

    Park, Jong Kyun; Kim, Sung Kyu; Park, Keun Bae

    2005-04-01

    International and domestic status of development activities of nuclear fusion energy technologies are analyzed and summarized. From these results a verifiable R and D strategy is derived which allows purposeful and successful participation in the ITER project and thus enables a domestic technological basis of the commercialization of nuclear fusion energy. A 45-year, three-stage plan is proposed with a detailed plan for the 10-year, 1st stage where a conceptual design of a Korean demonstration fusion power plant (KDEMO) will be developed as well as its key component designs such as breeder blanket

  16. Nash equilibrium strategies of generating companies (Gencos) in the simultaneous operation of active and reactive power market, with considering voltage stability margin

    International Nuclear Information System (INIS)

    Soleymani, S.

    2013-01-01

    Highlights: ► We model the behavior of Gencos in the active and reactive power markets. ► Genco’s strategy is modeled as a bi-level optimization problem. ► The ISO’s market clearing model is modified with applying generator APFs. ► Good forecast of Genco’s information will increase the accuracy of proposed method. ► Obtained profit of Gencos depend on their bidding strategy. - Abstract: As Gencos are responsible for providing active and reactive power generation, they should devise good bidding strategies for energy and reactive power market. The paper describes a method for analyzing the competition among transmission-constrained Gencos with incomplete information. The proposed methodology employs the Supply Function Equilibrium (SFE) for modeling a Genco’s bidding strategy in energy market and uses Expected Payment Function (EPF) to construct a bidding framework in the reactive power market. The problem of finding the optimum strategy of Gencos is modeled as a bi-level optimization problem, where the upper sub-problem represents individual Genco’s payoff and the lower sub-problem solves the ISO’s market clearing problem. The ISO’s market clearing model is modified with applying generator Active Participation Factors to improve the voltage stability margin. The IEEE 39 bus test system is used to verify the effectiveness of the proposed method.

  17. Balancing trust and power: a qualitative study of GPs perceptions and strategies for retaining patients in preventive health checks.

    Science.gov (United States)

    Broholm-Jørgensen, Marie; Guassora, Ann Dorrit; Reventlow, Susanne; Dalton, Susanne Oksbjerg; Tjørnhøj-Thomsen, Tine

    2017-03-01

    Little is known about how strategies of retaining patients are acted out by general practitioners (GPs) in the clinical encounter. With this study, we apply Grimens' (2009) analytical connection between trust and power to explore how trust and power appear in preventive health checks from the GPs' perspectives, and in what way trust and power affect and/or challenge strategies towards retaining patients without formal education. Data in this study were obtained through semi-structured interviews with GPs participating in an intervention project, as well as observations of clinical encounters. From the empirical data, we identified three dimensions of respect: respect for the patient's autonomy, respect for professional authority and respect as a mutual exchange. A balance of respect influenced trust in the relationship between GP and patients and the transfer of power in the encounter. The GPs articulated that a balance was needed in preventive health checks in order to establish trust and thus retain the patient in the clinic. One way this balance of respect was carried out was with the use of humour. To retain patients without formal education in the clinical encounter, the GPs balanced trust and power executed through three dimensions of respect. In this study, retaining patients was equivalent to maintaining a trusting relationship. A strategic use of the three dimensions of respect was applied to balance trust and power and thus build or maintain a trusting relationship with patients. KEY POINTS   Little is known about how strategies for retaining patients are acted out by GPs in preventive health checks.  •  Retaining patients requires a balance of trust and power, which is executed through three dimensions of respect by the GPs.  •  Challenges of recruiting and retaining patients in public health initiatives might be associated with the balance of respect.

  18. Visualizing Nanocatalysts in Action from Color Change Reaction to Magnetic Recycling and Reuse

    Science.gov (United States)

    Hudson, Reuben; Bishop, Alexandra; Glaisher, Samuel; Katz, Jeffrey L.

    2015-01-01

    A demonstration to highlight the utility and ease of handling environmentally benign magnetically recoverable nanoparticle catalysts is described. The demonstration offers two powerful visuals. The first is a color change oxidation of tetramethylbenzidine by hydrogen peroxide catalyzed by Fe[subscript 3]O[subscript 4] nanoparticles. The second,…

  19. Power Allocation Strategies for Distributed Space-Time Codes in Amplify-and-Forward Mode

    Directory of Open Access Journals (Sweden)

    Are Hjørungnes

    2009-01-01

    Full Text Available We consider a wireless relay network with Rayleigh fading channels and apply distributed space-time coding (DSTC in amplify-and-forward (AF mode. It is assumed that the relays have statistical channel state information (CSI of the local source-relay channels, while the destination has full instantaneous CSI of the channels. It turns out that, combined with the minimum SNR based power allocation in the relays, AF DSTC results in a new opportunistic relaying scheme, in which the best relay is selected to retransmit the source's signal. Furthermore, we have derived the optimum power allocation between two cooperative transmission phases by maximizing the average received SNR at the destination. Next, assuming M-PSK and M-QAM modulations, we analyze the performance of cooperative diversity wireless networks using AF opportunistic relaying. We also derive an approximate formula for the symbol error rate (SER of AF DSTC. Assuming the use of full-diversity space-time codes, we derive two power allocation strategies minimizing the approximate SER expressions, for constrained transmit power. Our analytical results have been confirmed by simulation results, using full-rate, full-diversity distributed space-time codes.

  20. Class and Home Problems: Carbon Dioxide Capture from Coal-Fired Power Plants Using Calcium Looping

    Science.gov (United States)

    Deshpande, Niranjani; Phalak, Nihar; Fan, Liang-Shih; Sundaresan, Sankaran

    2015-01-01

    Calcium looping is based on the simple premise of the reversible reaction between CO[subscript 2] and CaO. This reaction can be used for separation of CO2 from a mixture of gases; most notably the technology finds applications in CO[subscript 2] removal from gas streams in fossil fuel-based energy systems. This article gives a brief overview of…

  1. An optimal tuning strategy for tidal turbines.

    Science.gov (United States)

    Vennell, Ross

    2016-11-01

    Tuning wind and tidal turbines is critical to maximizing their power output. Adopting a wind turbine tuning strategy of maximizing the output at any given time is shown to be an extremely poor strategy for large arrays of tidal turbines in channels. This 'impatient-tuning strategy' results in far lower power output, much higher structural loads and greater environmental impacts due to flow reduction than an existing 'patient-tuning strategy' which maximizes the power output averaged over the tidal cycle. This paper presents a 'smart patient tuning strategy', which can increase array output by up to 35% over the existing strategy. This smart strategy forgoes some power generation early in the half tidal cycle in order to allow stronger flows to develop later in the cycle. It extracts enough power from these stronger flows to produce more power from the cycle as a whole than the existing strategy. Surprisingly, the smart strategy can often extract more power without increasing maximum structural loads on the turbines, while also maintaining stronger flows along the channel. This paper also shows that, counterintuitively, for some tuning strategies imposing a cap on turbine power output to limit loads can increase a turbine's average power output.

  2. Socio-economic impacts of low-carbon power generation portfolios: Strategies with and without CCS for the Netherlands

    International Nuclear Information System (INIS)

    Koelbl, Barbara S.; Broek, Machteld A. van den; Wilting, Harry C.; Sanders, Mark W.J.L.; Bulavskaya, Tatyana; Wood, Richard; Faaij, André P.C.; Vuuren, Detlef P. van

    2016-01-01

    Highlights: • We compare GHG mitigation policy including or excluding CCS on socio-economic impacts for the Netherlands. • We simulate these policy options in a global multiregional Input-Output Model with detailed bottom-up technology data. • Economy-wide differentials between these mitigation policies are small for Employment, GDP and Imports. • Notable impacts are found for the energy sector and some upstream sectors (natural gas, construction). • This pattern shows to base a choice on macroeconomic impacts is hard and it will affect strong and vested interests. - Abstract: Carbon Capture and Storage (CCS) could be an interesting option to mitigate greenhouse gas emissions in the Netherlands. This study compares a mitigation strategy for the Dutch power sector that includes CCS to one without on several socio-economic indicators. In particular, we calculate incremental gross value added (GVA), employment and import dependency impacts of two such low-carbon power production portfolios for the Netherlands. We combine technology specific techno-economic bottom-up data with a macro-economic multi-regional Input-Output-Table containing high sectoral detail. For the total economy, we find the differences between these scenarios to be small. Still, gross value added, and employment are lower under the CCS-inclusive strategy, while import dependency is higher. For the power sector, the differences between the scenarios are, however, considerable. Furthermore, our analysis shows that also for other sectors the differences between the scenarios could be large. For instance, a CCS-exclusive strategy leads to considerably higher GVA and employment in domestic construction services, while the CCS-inclusive strategy comes with considerably higher GVA and employment for natural gas mining and related upstream sectors.

  3. Group Theory and Crystal Field Theory: A Simple and Rigorous Derivation of the Spectroscopic Terms Generated by the t[subscript 2g][superscript 2] Electronic Configuration in a Strong Octahedral Field

    Science.gov (United States)

    Morpurgo, Simone

    2007-01-01

    The principles of symmetry and group theory are applied to the zero-order wavefunctions associated with the strong-field t[subscript 2g][superscript 2] configuration and their symmetry-adapted linear combinations (SALC) associated with the generated energy terms are derived. This approach will enable students to better understand the use of…

  4. Strategy for utilizing nuclear power

    International Nuclear Information System (INIS)

    Martens, E.J.

    1977-01-01

    One of the national goals is to achieve independence in the area of energy supplies in the next few years. It is believed that attaining this goal will require extensive utilization of nuclear power in conventional fission reactors. It is proposed that the best way to develop the nuclear resource is through government ownership of the reactors. It is argued that this will minimize the risks associated with the nuclear-power option and clear the way for its exploitation

  5. Fuel supply strategy for power projects in Asia

    International Nuclear Information System (INIS)

    Boyd, D.

    1997-01-01

    Electricity generation is forecast to grow in Asia over the next twenty years. This will bring with it a significant growth in demand for energy resources. Major Asian utility coal procurement strategy to date has aimed at securing a balance between two conflicting needs - security of supply and low cost of supply. Despite the oversupply of coal in the eighties, the two countries experiencing significant growth in demand, Japan and Korea, planned their fuel strategies to ensure security of supply. The supply shortage over the past two years has justified their forward thinking in keeping long term coal contracts in place. Changes are already happening. Recent developments are seeing a move towards the positive attributes of low ash/low sulphur coals appropriately focusing suppliers thoughts on the need in the future to develop and concentrate on environmentally attractive coals to achieve greater returns. Indeed, generally there is a trend in North Asia to demand coal with lower sulphur, and lower ash. The aim now should be to persuade consumers to amend the narrow benchmark view in favour of one that considers the value in use of a particular coal to the customer. The method of pricing thermal coals is also likely to be influenced by the liberalization of the electricity market itself. The introduction of competition amongst generators and the appearance and growth of the Independent Power Producers could well see further pressure on the current simplistic benchmark system. Those financing such projects will seek to reduce risk by every means possible and, in particular, will want to be confident of the long term security of coal supplies

  6. Effects of spatial location and household wealth on health insurance subscription among women in Ghana.

    Science.gov (United States)

    Kumi-Kyereme, Akwasi; Amo-Adjei, Joshua

    2013-06-17

    This study compares ownership of health insurance among Ghanaian women with respect to wealth status and spatial location. We explore the overarching research question by employing geographic and proxy means targeting through interactive analysis of wealth status and spatial issues. The paper draws on the 2008 Ghana Demographic and Health Survey. Bivariate descriptive analysis coupled with binary logistic regression estimation technique was used to analyse the data. By wealth status, the likelihood of purchasing insurance was significantly higher among respondents from the middle, richer and richest households compared to the poorest (reference category) and these differences widened more profoundly in the Northern areas after interacting wealth with zone of residence. Among women at the bottom of household wealth (poorest and poorer), there were no statistically significant differences in insurance subscription in all the areas. The results underscore the relevance of geographic and proxy means targeting in identifying populations who may be need of special interventions as part of the efforts to increase enrolment as well as means of social protection against the vulnerable.

  7. New nuclear power in the UK: A strategy for energy security?

    International Nuclear Information System (INIS)

    Watson, Jim; Scott, Alister

    2009-01-01

    The aim of this paper is to explore the extent to which the construction of new nuclear power plants in the UK can safeguard or enhance energy security. The paper starts with a discussion of energy security, and breaks it down into four main categories of threat. These include threats due to fossil fuel scarcity and external disruptions, problems due to a lack of investment in infrastructure, threats due to technology or infrastructure failure, and risks due to domestic activism or terrorism. The paper then discusses one of the most common strategies put forward to improve security-the promotion of diversity within energy systems. Following this, the paper assesses the potential for new nuclear investment to ameliorate security threats in each of the four categories introduced earlier in the paper. The paper concludes that whilst nuclear investment can help to mitigate some threats to UK energy security, the government's case for supporting this investment ignores some equally important security issues. As a result, the energy security case for nuclear power has not yet been made.

  8. New nuclear power in the UK. A strategy for energy security?

    Energy Technology Data Exchange (ETDEWEB)

    Watson, Jim; Scott, Alister [Sussex Energy Group, SPRU, The Freeman Centre, University of Sussex, Brighton, East Sussex BN1 9QE (United Kingdom)

    2009-12-15

    The aim of this paper is to explore the extent to which the construction of new nuclear power plants in the UK can safeguard or enhance energy security. The paper starts with a discussion of energy security, and breaks it down into four main categories of threat. These include threats due to fossil fuel scarcity and external disruptions, problems due to a lack of investment in infrastructure, threats due to technology or infrastructure failure, and risks due to domestic activism or terrorism. The paper then discusses one of the most common strategies put forward to improve security - the promotion of diversity within energy systems. Following this, the paper assesses the potential for new nuclear investment to ameliorate security threats in each of the four categories introduced earlier in the paper. The paper concludes that whilst nuclear investment can help to mitigate some threats to UK energy security, the government's case for supporting this investment ignores some equally important security issues. As a result, the energy security case for nuclear power has not yet been made. (author)

  9. New nuclear power in the UK: A strategy for energy security?

    Energy Technology Data Exchange (ETDEWEB)

    Watson, Jim, E-mail: w.j.watson@sussex.ac.u [Sussex Energy Group, SPRU, Freeman Centre, University of Sussex, Brighton, East Sussex BN1 9QE (United Kingdom); Scott, Alister [Sussex Energy Group, SPRU, Freeman Centre, University of Sussex, Brighton, East Sussex BN1 9QE (United Kingdom)

    2009-12-15

    The aim of this paper is to explore the extent to which the construction of new nuclear power plants in the UK can safeguard or enhance energy security. The paper starts with a discussion of energy security, and breaks it down into four main categories of threat. These include threats due to fossil fuel scarcity and external disruptions, problems due to a lack of investment in infrastructure, threats due to technology or infrastructure failure, and risks due to domestic activism or terrorism. The paper then discusses one of the most common strategies put forward to improve security-the promotion of diversity within energy systems. Following this, the paper assesses the potential for new nuclear investment to ameliorate security threats in each of the four categories introduced earlier in the paper. The paper concludes that whilst nuclear investment can help to mitigate some threats to UK energy security, the government's case for supporting this investment ignores some equally important security issues. As a result, the energy security case for nuclear power has not yet been made.

  10. UP-report. The power system. Basis of the Development platform. Power to Swedish Energy Agency's strategy work FOKUS; UP-rapport. Kraftsystemet. Underlag fraan Utvecklingsplattformen. Kraft till Energimyndighetens strategiarbete FOKUS

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    The report serves as input to to Swedish Energy Agency's strategies and priorities for research and innovation in the power system for the period 2011 - 2016. The report has been compiled by members of the development platform Kraft. This report provides background and circumstances for the power system theme, and proposed priorities and activities for future efforts in this area. The development platform has contributed with valuable experience and skills that enabled the Swedish Energy Agency to then develop a strategy that meets the needs of society and business.

  11. Effect of heating strategy on power consumption and performance of a pilot plant anaerobic digester.

    Science.gov (United States)

    Espinosa-Solares, Teodoro; Valle-Guadarrama, Salvador; Bombardiere, John; Domaschko, Max; Easter, Michael

    2009-05-01

    The effect of heating strategy on power consumption and performance of a pilot plant anaerobic digester treating chicken litter, under thermophilic conditions, has been studied. Heating strategy was evaluated using three different spans (0.2 degrees C, 0.6 degrees C, and 1.0 degree C) for triggering the temperature control system from target temperature (56.7 degrees C). The hydraulic retention time in the pilot plant digester was in the range of 32 to 37 days, varying the total solids concentration fed from 5% to 6%. The results showed that under the experimental conditions, heating was the most energy-demanding process with 95.5% of the energy used. Increments up to 7.5% and 3.8%, respectively, on mechanical and heating power consumption, were observed as the span, for triggering the temperature control system from target temperature, was increased. Under the experimental conditions studied here, an increment of 30.6% on the global biodigester performance index was observed when a span of 1.0 degree C was compared to the one of 0.2 degrees C.

  12. Decommissioning strategy and schedule for a multiple reactor nuclear power plant site

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, Deiglys Borges; Moreira, Joao M.L.; Maiorino, Jose Rubens, E-mail: deiglys.monteiro@ufabc.edu.br, E-mail: joao.moreira@ufabc.edu.br, E-mail: joserubens.maiorino@ufabc.edu.br [Universidade Federal do ABC (CECS/UFABC), Santo Andre, SP (Brazil). Centro de Engenharia, Modelagem e Ciencias Aplicadas

    2015-07-01

    The decommissioning is an important part of every Nuclear Power Plant life cycle gaining importance when there are more than one plant at the same site due to interactions that can arise from the operational ones and a decommissioning plant. In order to prevent undesirable problems, a suitable strategy and a very rigorous schedule should implemented and carried. In this way, decommissioning tasks such as fully decontamination and dismantling of activated and contaminated systems, rooms and structures could be delayed, posing as an interesting option to multiple reactor sites. The present work aims to purpose a strategy and a schedule for the decommissioning of a multiple reactor site highlighting the benefits of delay operational tasks and constructs some auxiliary services in the site during the stand by period of the shutdown plants. As a case study, will be presented a three-reactor site which the decommissioning process actually is in planning stage and that should start in the next decade. (author)

  13. Decommissioning strategy and schedule for a multiple reactor nuclear power plant site

    International Nuclear Information System (INIS)

    Monteiro, Deiglys Borges; Moreira, Joao M.L.; Maiorino, Jose Rubens

    2015-01-01

    The decommissioning is an important part of every Nuclear Power Plant life cycle gaining importance when there are more than one plant at the same site due to interactions that can arise from the operational ones and a decommissioning plant. In order to prevent undesirable problems, a suitable strategy and a very rigorous schedule should implemented and carried. In this way, decommissioning tasks such as fully decontamination and dismantling of activated and contaminated systems, rooms and structures could be delayed, posing as an interesting option to multiple reactor sites. The present work aims to purpose a strategy and a schedule for the decommissioning of a multiple reactor site highlighting the benefits of delay operational tasks and constructs some auxiliary services in the site during the stand by period of the shutdown plants. As a case study, will be presented a three-reactor site which the decommissioning process actually is in planning stage and that should start in the next decade. (author)

  14. Xenon Acquisition Strategies for High-Power Electric Propulsion NASA Missions

    Science.gov (United States)

    Herman, Daniel A.; Unfried, Kenneth G.

    2015-01-01

    The benefits of high-power solar electric propulsion (SEP) for both NASA's human and science exploration missions combined with the technology investment from the Space Technology Mission Directorate have enabled the development of a 50kW-class SEP mission. NASA mission concepts developed, including the Asteroid Redirect Robotic Mission, and those proposed by contracted efforts for the 30kW-class demonstration have a range of xenon propellant loads from 100's of kg up to 10,000 kg. A xenon propellant load of 10 metric tons represents greater than 10% of the global annual production rate of xenon. A single procurement of this size with short-term delivery can disrupt the xenon market, driving up pricing, making the propellant costs for the mission prohibitive. This paper examines the status of the xenon industry worldwide, including historical xenon supply and pricing. The paper discusses approaches for acquiring on the order of 10 MT of xenon propellant considering realistic programmatic constraints to support potential near-term NASA missions. Finally, the paper will discuss acquisitions strategies for mission campaigns utilizing multiple high-power solar electric propulsion vehicles requiring 100's of metric tons of xenon over an extended period of time where a longer term acquisition approach could be implemented.

  15. New power expansion strategy and a low GHG emitting economy in Korea

    International Nuclear Information System (INIS)

    Chung, W. S.; Yun, S. W.; Lee, D. S.; Jeong, J. W.

    2008-01-01

    According to mounting environmental concerns and an increased number of environmental restrictions, a new power expansion strategy is being suggested in Korea. Low carbon emitting technologies are a cost- and environment-effective renewable energy technology for producing electricity (except large hydropower) and the fastest growing market after the launch of the 'The 3. Basic Plan for Long-Term Electricity Supply and Demand' in 2006 in Korea. Even though some renewable power plants don't use any fuel or materials during their operation, they still contribute to climate change. This is due to the emission of greenhouse gases (GHG) from the fossil fuels combusted for their components manufacturing, construction, and dismantling. So the aim of this analysis is to assess the Global Warming Potential (GWP) during the whole life cycle for each candidate technology and to estimate how much they contribute to GHG emissions by introducing low-carbon energy sources up to 2020 in Korea. (authors)

  16. Compensating active power imbalances in power system with large-scale wind power penetration

    DEFF Research Database (Denmark)

    Basit, Abdul; Hansen, Anca Daniela; Altin, Müfit

    2016-01-01

    Large-scale wind power penetration can affectthe supply continuity in the power system. This is a matterof high priority to investigate, as more regulating reservesand specified control strategies for generation control arerequired in the future power system with even more highwind power penetrat...

  17. Subscribers and newspaper subscriptions in Spain at the beginning of the XX century. Notes from an asturian perspective

    Directory of Open Access Journals (Sweden)

    Víctor Rodríguez Infiesta

    2008-12-01

    Full Text Available In the first decades of the XX century the possibility of a particular newspaper having a high number of subscribers was, from the point of view of the newspaper publishers, the best guarantee of its stability. However it was not all advantages in a system which gave rise to numerous complaints and created a peculiar relationship with the subscriber. By various means —delivery men, the post and public establishments, principally— the subscription service continually generated situations illustrative of the level of development of the Spanish press in years in which progress accelerates and deficiencies and limitations also become apparent. Limitations which, particularly in an outlying region with mostly inadequate means of communication such as Asturias, could become one of the main factors delaying the establishment of a large press with mass-readership.

  18. A flexible control strategy of plug-in electric vehicles operating in seven modes for smoothing load power curves in smart grid

    International Nuclear Information System (INIS)

    Khemakhem, Siwar; Rekik, Mouna; Krichen, Lotfi

    2017-01-01

    Plug-in electric vehicles (PEVs) seem to be an interesting new electrical load for improving the reliability of smart grid. The purpose of this work is to investigate a supervision strategy based on regulated charging of PEVs in order to guarantee an optimized power management of the system and consequently a flatter power demand curve. The system mainly includes PEVs powered by a Lithium-ion battery ensuring the charging and discharging operations of these PEVs at home and a daily load power demanded by home appliances. The purpose of the considered strategy is to detect the connection status of each PEV and to establish the priority order between these PEVs with certain flexibility which results in managing the PEVs through seven operating modes. The response of the control algorithm enables to ensure the power flow exchange between the PEVs and the electrical grid, especially at rush hours, and to minimize load power variance aiming to achieve the smoothness for the power demand curve and to reduce the stress of the electrical grid. The simulation results are presented in order to illustrate the efficiency of this power control approach. - Highlights: • A flexible power management algorithm of Plug-in electric vehicle is proposed. • This control can be applied for any home equipped with two PEVs. • The response is to ensure the power flow exchange between PEVs and power grid. • The main contribution is to achieve the smoothness for the daily power demand curve.

  19. Fuel cycle strategies for growth of nuclear power in India

    International Nuclear Information System (INIS)

    Purushotham, D.S.C.; Balu, K.

    2002-01-01

    Nuclear power has been identified as an essential component to meet the growing energy demand of India. The three stage fuel cycle strategy to achieve this with the available resources envisages the use of natural uranium in PHWRs in the first stage, the plutonium-uranium/plutonium-thorium cycles in Fast reactors/Advanced HWRs in the second stage, followed by exploitation of essentially U233 in the third stage. The technologies necessary for this programme, mainly through the back-end of the fuel cycle including reprocessing, waste management and recycle of Pu have been developed accordingly, as a direct result of the closed fuel cycle policy followed by us from the very beginning. This paper addresses the considerations involved in several activities taken up in our programme, their current status and plans for the future. (author)

  20. Mildly disabled persons with multiple sclerosis use similar net joint power strategies as healthy controls when walking speed increases.

    Science.gov (United States)

    Brincks, John; Christensen, Lars Ejsing; Rehnquist, Mette Voigt; Petersen, Jesper; Sørensen, Henrik; Dalgas, Ulrik

    2018-01-01

    To improve walking in persons with multiple sclerosis (MS), it is essential to understand the underlying mechanisms of walking. This study examined strategies in net joint power generated or absorbed by hip flexors, hip extensors, hip abductors, knee extensors, and plantar flexors in mildly disabled persons with MS and healthy controls at different walking speeds. Thirteen persons with MS and thirteen healthy controls participated and peak net joint power was calculated using 3D motion analysis. 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. In contrast to previous studies, these findings suggest that mildly disabled persons with MS used similar kinetic strategies as healthy controls to increase walking speed.

  1. Waste management strategy for nuclear fusion power systems from a regulatory perspective

    Energy Technology Data Exchange (ETDEWEB)

    Heckman, R.A.

    1977-12-06

    A waste management strategy for future nuclear fusion power systems is developed using existing regulatory methodology. The first step is the development of a reference fuel cycle. Next, the waste streams from such a facility are identified. Then a waste management system is defined to safely handle and dispose of these wastes. The future regulator must identify the decisions necessary to establish waste management performance criteria. The data base and methodologies necessary to make these decisions must then be developed. Safe management of nuclear fusion wastes is not only a technological challenge, but encompasses significant social, political, and ethical questions as well.

  2. Waste management strategy for nuclear fusion power systems from a regulatory perspective

    International Nuclear Information System (INIS)

    Heckman, R.A.

    1977-01-01

    A waste management strategy for future nuclear fusion power systems is developed using existing regulatory methodology. The first step is the development of a reference fuel cycle. Next, the waste streams from such a facility are identified. Then a waste management system is defined to safely handle and dispose of these wastes. The future regulator must identify the decisions necessary to establish waste management performance criteria. The data base and methodologies necessary to make these decisions must then be developed. Safe management of nuclear fusion wastes is not only a technological challenge, but encompasses significant social, political, and ethical questions as well

  3. Impact of Battery Energy Storage System Operation Strategy on Power System: An Urban Railway Load Case under a Time-of-Use Tariff

    Directory of Open Access Journals (Sweden)

    Hyeongig Kim

    2017-01-01

    Full Text Available Customer-owned battery energy storage systems (BESS have been used to reduce electricity costs of energy storage owners (ESOs under a time-of-use (TOU tariff in Korea. However, the current TOU tariff can unintentionally induce customer’s electricity usage to have a negative impact on power systems. This paper verifies the impact of different BESS operation strategies on power systems under a TOU tariff by analyzing the TOU tariff structure and the customer’s load pattern. First, several BESS operation strategies of ESO are proposed to reduce the electricity cost. In addition, a degradation cost calculation method for lithium ion batteries is considered for the ESO to determine the optimal BESS operation strategy that maximizes both electricity cost and annual investment cost. The optimal BESS operation strategy that maximizes ESO’s net benefit is illustrated by simulation using an urban railway load data from Namgwangju Station, Korea. The results show that BESS connected to urban railway loads can negative impact power system operation. This is due to the high BESS degradation costs and lack of incentive of differential rates in TOU tariff that can effectively induce proper demand response.

  4. An optimal tuning strategy for tidal turbines

    Science.gov (United States)

    2016-01-01

    Tuning wind and tidal turbines is critical to maximizing their power output. Adopting a wind turbine tuning strategy of maximizing the output at any given time is shown to be an extremely poor strategy for large arrays of tidal turbines in channels. This ‘impatient-tuning strategy’ results in far lower power output, much higher structural loads and greater environmental impacts due to flow reduction than an existing ‘patient-tuning strategy’ which maximizes the power output averaged over the tidal cycle. This paper presents a ‘smart patient tuning strategy’, which can increase array output by up to 35% over the existing strategy. This smart strategy forgoes some power generation early in the half tidal cycle in order to allow stronger flows to develop later in the cycle. It extracts enough power from these stronger flows to produce more power from the cycle as a whole than the existing strategy. Surprisingly, the smart strategy can often extract more power without increasing maximum structural loads on the turbines, while also maintaining stronger flows along the channel. This paper also shows that, counterintuitively, for some tuning strategies imposing a cap on turbine power output to limit loads can increase a turbine’s average power output. PMID:27956870

  5. The impact of European balancing rules on wind power economics and on short-term bidding strategies

    International Nuclear Information System (INIS)

    Chaves-Ávila, J.P.; Hakvoort, R.A.; Ramos, A.

    2014-01-01

    Wind power represents a significant percentage of the European generation mix and this will increase to fulfill the renewable energy targets. Different balancing rules are applied to wind power among the countries; for instance, to what extent wind power producers (WPPs) are responsible for the energy imbalances and how those imbalances are penalized. This paper discusses those different rules and evaluates their effects on WPP bidding strategies. To do so, a quantitative analysis is presented for an offshore wind farm, considering the differences in the balancing rules and prices of Belgium, Denmark, Germany and the Netherlands. The quantitative approach consists of a stochastic optimization model that maximizes the profits of a WPP by trading in different markets (day-ahead and intraday) and computes the final energy delivered. The model considers uncertainties of most important parameters such as wind energy forecasts and prices at different time frames. The results show that the imbalance pricing design and the allocation of balance responsibility significantly affect WPP’ revenues. Additionally, WPPs deviate differently from the expected energy depending on the balancing rules, which can impact the system. Furthermore, these balancing rules should be considered with other market regulations, such as the design of support schemes. - Highlights: • European countries apply different imbalance pricing rules. • The allocation of balance responsibility to wind power varies between the countries. • A stochastic optimization model is used to compare the effect of balancing rules. • Balancing rules have an important impact on wind generators bidding strategies. • Balancing rules have also an effect on the system imbalances

  6. Survey and comparison of nuclear power strategy and concepts worldwide

    International Nuclear Information System (INIS)

    Kupitz, J.; Breidenbach, L.

    1995-01-01

    The steady growth of the world's population and the enhancement of the standard of living will make the demand for energy grow correspondingly. Not only for economic reasons, but also in the interest of the environment and the global climate will strategies for meeting the global energy demand have recourse to nuclear energy. One can even expect a renaissance of nuclear technology based on evolutionary and innovative developments, as nuclear energy is the sole energy source offering the potentials of power generation at justifiable technological risk and economic investment, while contributing to curbing CO 2 emissions. Nuclear technology transfer to the developing countries however is an important task in this strategy for the future. Transfer of know-how and simpler technical standards are required (common problems, common rules, common products). Also, the development of breeder reactors and high-temperature reactors should be a major objective, in order to fully exploit the nuclear option, i.e. conserve energy resources, and meet the demand for process heat. The wide range of tasks ahead in the development of advanced nuclear reactors requires enhanced cooperation and exchange of information at international level. Experience and capacities of the IAEA make this organisation the proper and sole available global forum for performing the tasks to be fulfilled, and Member Countries of the IAEA should support the organisation also in their own interest. (orig.) [de

  7. Reactor design and operation strategies for a large-scale packed-bed CLC power plant with coal syngas

    NARCIS (Netherlands)

    Spallina, V.; Chiesa, P.; Martelli, E; Gallucci, F.; Romano, M.C.; Lozza, G.; Sint Annaland, van M.

    2015-01-01

    This paper deals with the design and operation strategies of dynamically operated packed-bed reactors (PBRs) of a chemical looping combustion (CLC) system included in an integrated gasification combined cycle (IGCC) for electric power generation with low CO2 emission from coal. The CLC reactors,

  8. Mitigation Emission Strategy Based on Resonances from a Power Inverter System in Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Li Zhai

    2016-05-01

    responsible elements were determined by the calculation through the equivalent circuits. A combination of mitigation strategies including adding common-mode (CM ferrite chokes through the Y-caps and the AC bus bar was designed to mitigate the resonances at 6 MHz, 11 MHz, and 26 MHz related to the CM conducted emission by IGBT switching and the radiated emission of the AC cable. The values of Z11 decreased respectively by 15 dB at 6 MHz, 0.4 dB at 11 MHz, and 11.5 dB at 26 MHz and the values of S21 decreased respectively by 8.6 dB at 6 MHz, 7 dB at 11 MHz, and 6.3 dB at 26 MHz. An equivalent model of the power inverter system for real-time simulation in time domain was built to validate the mitigation strategy in simulation software PSPICE.

  9. Integrated strategy for N-methylformanilide production from carbon dioxide of flue gas in coal-fired power plant

    International Nuclear Information System (INIS)

    Han, Jeehoon

    2017-01-01

    Highlights: • A ‘green’ N-methylformanilide production process based new carbon dioxide conversion technologies is developed. • Monoethanolamine-based system for capturing carbon dioxide from the flue gas of a coal-fired power plant is deployed. • Gamma-valerolactone is used a solvent and catalyst for converting carbon dioxide to N-methylformanilide. • New separations for recovery of N-methylformanilide and gamma-valerolactone are developed. • Economic evaluation of the proposed process is performed. - Abstract: In this work, an integrated strategy is developed for producing N-methylformanilide from the carbon dioxide of flue gas in a coal-fired power plant. Based on lab-scale experimental studies presenting maximum yields (96%) with low reaction concentrations (below 25 wt% reactants) using large volumes of gamma-valerolactone as a solvent and catalyst, the integrated strategy focuses on the development of commercial-scale processes that consist of a monoethanolamine-based carbon dioxide separation subsystem and a catalytic conversion subsystem of N-Methylaniline with carbon dioxide to N-methylformanilide. Moreover, a heat exchanger network is designed to minimize the total energy requirements by transferring the heat between subsystems. In the proposed integrated strategy, the energy efficiency after heat integration (77.5%) is higher than that before heat integration (74.5%). Economic analysis results show that the minimum selling price of N-methylformanilide ($1592.1 Mt"−"1 using the best possible parameters) for use in this integrated strategy is cost-competitive with the current market price ($2984 Mt"−"1).

  10. Maximum Power Point Tracking in Variable Speed Wind Turbine Based on Permanent Magnet Synchronous Generator Using Maximum Torque Sliding Mode Control Strategy

    Institute of Scientific and Technical Information of China (English)

    Esmaeil Ghaderi; Hossein Tohidi; Behnam Khosrozadeh

    2017-01-01

    The present study was carried out in order to track the maximum power point in a variable speed turbine by minimizing electromechanical torque changes using a sliding mode control strategy.In this strategy,fhst,the rotor speed is set at an optimal point for different wind speeds.As a result of which,the tip speed ratio reaches an optimal point,mechanical power coefficient is maximized,and wind turbine produces its maximum power and mechanical torque.Then,the maximum mechanical torque is tracked using electromechanical torque.In this technique,tracking error integral of maximum mechanical torque,the error,and the derivative of error are used as state variables.During changes in wind speed,sliding mode control is designed to absorb the maximum energy from the wind and minimize the response time of maximum power point tracking (MPPT).In this method,the actual control input signal is formed from a second order integral operation of the original sliding mode control input signal.The result of the second order integral in this model includes control signal integrity,full chattering attenuation,and prevention from large fluctuations in the power generator output.The simulation results,calculated by using MATLAB/m-file software,have shown the effectiveness of the proposed control strategy for wind energy systems based on the permanent magnet synchronous generator (PMSG).

  11. 77 FR 61594 - Prairie Power, Inc.; Notice of Filing

    Science.gov (United States)

    2012-10-10

    ... Superseding Proposed Revenue Requirement for reactive supply service under Midwest Independent Transmission... ``eSubscription'' link on the Web site that enables subscribers to receive email notification when a...

  12. Financial barriers and pricing strategies related to participation in sports activities: the perceptions of people of low income.

    Science.gov (United States)

    Steenhuis, Ingrid H M; Nooy, Steffie B C; Moes, Machiel J G; Schuit, Albertine J

    2009-11-01

    Physical activity levels in most affluent countries are low and many people do not meet the current recommendations. Particularly for people with a low income, economic strategies seem promising to stimulate taking part in sports activities. This study investigated the importance of economic restraints for taking part in sports activities as well as perceptions of low-income people toward different pricing interventions. A qualitative study was conducted, using semistructured, individual interviews with 27 low-income men and women. The framework approach was used to analyze the transcripts of the interviews. The respondents considered finances to be an important barrier for participating in sports activities, together with some individual barriers. Promising pricing strategies are a discount on the subscription to the fitness or sports club, a 1 month free trial, and free entrance to the swimming pool once a week. Pricing strategies may be a promising intervention to increase physical activity levels of low-income people. However, this study indicates that this should be coupled with an intervention directed at individual barriers. Some pricing strategies will be used and appreciated more by low-income people than other pricing strategies. In addition, pricing strategies should be tailored to individual needs and preferences.

  13. Code of Conduct for wind-power projects - Phase 3; Code of Conduct fuer windkraftprojekte. Phase 3 Machbarkeit und Strategie

    Energy Technology Data Exchange (ETDEWEB)

    Strub, P. [Pierre Strub, freischaffender Berater, Binningen (Switzerland); Ziegler, Ch. [Inter Act, Basel (Switzerland)

    2008-11-15

    This paper discusses the results of phase three of a project concerning wind-power projects. Feasibility and strategy aspects are examined and discussed. The current state of the wind power market is discussed on the basis of the results of a survey made on the subject. The social acceptance of wind power installations is discussed, whereby the rejection of particular projects is compared with a general lack of acceptance. Requirements placed on such projects and possible solutions are discussed. Finally, the feasibility of setting up a code of conduct in the area of wind-power projects is discussed and the definition of further instruments is examined

  14. Potentiality Prediction of Electric Power Replacement Based on Power Market Development Strategy

    Science.gov (United States)

    Miao, Bo; Yang, Shuo; Liu, Qiang; Lin, Jingyi; Zhao, Le; Liu, Chang; Li, Bin

    2017-05-01

    The application of electric power replacement plays an important role in promoting the development of energy conservation and emission reduction in our country. To exploit the potentiality of regional electric power replacement, the regional GDP (gross domestic product) and energy consumption are taken as potentiality evaluation indicators. The principal component factors are extracted with PCA (principal component analysis), and the integral potentiality analysis is made to the potentiality of electric power replacement in the national various regions; a region is taken as a research object, and the potentiality of electric power replacement is defined and quantified. The analytical model for the potentiality of multi-scenario electric power replacement is developed, and prediction is made to the energy consumption with the grey prediction model. The relevant theoretical research is utilized to realize prediction analysis on the potentiality amount of multi-scenario electric power replacement.

  15. How does a change in the control room design affect diagnostic strategies in nuclear power plants?

    International Nuclear Information System (INIS)

    Kim, Dong Young; Kim, Jonghyun

    2014-01-01

    Recently, main control rooms have been considerably changed by modern computer techniques. Some of the features that distinguish digital control rooms from conventional, analog rooms in nuclear power plants include advanced alarm systems, graphic information display systems, computerized procedure systems, and soft control. These features can bring changes in operator tasks, changing the characteristics of tasks or creating new tasks for operators. It is especially expected that these features may bring out changes in the operator's diagnostic tasks and strategies in a digital control room as compared with an analog control room. This study investigates the differences in the operator's diagnostic tasks and strategies in analog and digital control rooms. This study also attempts to evaluate how new systems in a digital control room affect diagnostic strategies. Three different approaches, which are complementary, are used to identify diagnostic strategies in the digital control room and in the analog control room: (1) observation in the simulator, (2) interview with operators, and (3) a literature review. The results show that the digital control room introduces new diagnosis strategies compared with the analog control room while also changing the characteristics of the strategies, mostly by gaining more support from the computerized system. (author)

  16. Strategies to overcome barriers for cleaner generation technologies in small developing power systems: Sri Lanka case study

    International Nuclear Information System (INIS)

    Wijayatunga, Priyantha D.C.; Siriwardena, Kanchana; Fernando, W.J.L.S.; Shrestha, Ram M.; Attalage, Rahula A.

    2006-01-01

    The penetration of cleaner and energy efficient technologies in small power systems such as the one in Sri Lanka has encountered many problems. This has caused major concerns among the policy makers, mainly in the context of the growing need to reduce harmful emissions in the electricity supply industry from the point of view of both local environmental pollution as well as the global warming concerns. This paper presents the outcome of a study involved in identifying and ranking the barriers to the promotion of cleaner and energy efficient technologies and strategies to overcome these barriers in Sri Lanka. Barriers for renewable energy based systems such as wind and wood fuel fired plants (dendro thermal power) and cleaner technologies such as liquefied natural gas (LNG) fired combined cycle and IGCC (coal) were identified based on a survey. A direct assessment multi-criteria decision making method called Analytic Hierarchy Process (AHP) was used to rank the barriers. The most effective strategies are proposed to address the three major barriers for each of these technologies based on extensive discussions with all the stakeholders in the electricity industry. It was found that lack of financing instruments, high initial cost and lack of assurance of resource supply or availability are the main barriers for renewable technologies. As for cleaner fuel and technology options associated with conventional generation systems, the lack of a clear government policy, uncertainty of fuel supplies and their prices and the reliability of the technologies themselves are the major barriers. Strategies are identified to overcome the above barriers. Establishment of a proper feed in tariff, geographical diversification of installations and capacity building in commercial banks are suggested for wind power. Investment incentives, streamlining of wood production and research on site identification are proposed for wood fuel fired plants. Also the study suggests delayed

  17. Resistance Training Using Different Hypoxic Training Strategies: a Basis for Hypertrophy and Muscle Power Development

    OpenAIRE

    Feriche, Bel?n; Garc?a-Ramos, Amador; Morales-Artacho, Antonio J.; Padial, Paulino

    2017-01-01

    The possible muscular strength, hypertrophy, and muscle power benefits of resistance training under environmental conditions of hypoxia are currently being investigated. Nowadays, resistance training in hypoxia constitutes a promising new training strategy for strength and muscle gains. The main mechanisms responsible for these effects seem to be related to increased metabolite accumulation due to hypoxia. However, no data are reported in the literature to describe and compare the efficacy of...

  18. Perception of quality of health delivery and health insurance subscription in Ghana.

    Science.gov (United States)

    Amo-Adjei, Joshua; Anku, Prince Justin; Amo, Hannah Fosuah; Effah, Mavis Osei

    2016-07-29

    National health insurance schemes (NHIS) in developing countries and perhaps in developed countries as well is a considered a pro-poor intervention by helping to bridge the financial burden of access to quality health care. Perceptions of quality of health service could have immense impacts on enrolment. This paper shows how perception of service quality under Ghana's insurance programme contributes to health insurance subscription. The study used the 2014 Ghana Demographic and Health Survey (GDHS) dataset. Both descriptive proportions and binary logistic regression techniques were applied to generate results that informed the discussion. Our results show that a high proportion of females (33 %) and males (35 %) felt that the quality of health provided to holders of the NHIS card was worse. As a result, approximately 30 % of females and 22%who perceived health care as worse by holding an insurance card did not own an insurance policy. While perceptions of differences in quality among females were significantly different (AOR = 0.453 [95 % CI = 0.375, 0.555], among males, the differences in perceptions of quality of health services under the NHIS were independent in the multivariable analysis. Beyond perceptions of quality, being resident in the Upper West region was an important predictor of health insurance ownership for both males and females. For such a social and pro-poor intervention, investing in quality of services to subscribers, especially women who experience enormous health risks in the reproductive period can offer important gains to sustaining the scheme as well as offering affordable health services.

  19. A Control Strategy of DC Building Microgrid Connected to the Neighborhood and AC Power Network

    Directory of Open Access Journals (Sweden)

    Thi Thuong Huyen Ma

    2017-05-01

    Full Text Available Recently, the use of DC microgrid distribution system has become more attractive than traditional AC systems due to their energy efficiency and ability to easily integrate with renewable energy sources and batteries. This paper proposes a 500 V DC microgrid which consists of a 20 kWp photovoltaic panel, batteries, and DC loads. A hierarchical control strategy to ensure balance power of the DC microgrid and the maintenance of common DC bus voltage is presented. The capability of exchanging power energy of the microgrid with the power system of neighborhood buildings is also considered. Typical operation modes are simulated in the Matlab/simulink environment to confirm the good performance of the controllers and the efficiency of appropriately controlling the charge–discharge of the battery system. This research is expected to bring benefits to the design and operation of the system, such as reducing the capacity of batteries, increasing the self-supply of buildings, and decreasing the electricity demand from the AC grid.

  20. Innovative Strategy in Shrimp Potiguar: Asymmetries Power Generation and Implications for Policy Innovation

    Directory of Open Access Journals (Sweden)

    Mariana Baldi

    2012-12-01

    Full Text Available This paper aims to analyze the technological trajectory and the actors – public and private - political behave in the carciniculture network (cultivate of shrimp in the federal estate of Rio Grande do Norte. The research was based on both embeddedness and cluster policy approach. The case study was based on bibliographic, archives, and empirical data, whose primary data were collected through semi-structured interviews carried on with 10 members of different organizations from carciniculture sector in the period 2009-2010, as well as interviews already conducted in the area since the year 2005. These data were submitted to content analysis with longitudinal and descriptive approach. Along the technological trajectory of the cluster we highlighted opportunities and limits for innovative strategies generated by asymmetries of power and ability to influence actors in the network. We highlight the relationship between 'power network' and 'links established with public actors' as well as the implications for innovation along the trajectory generated by a more or less state interference.

  1. CPU time reduction strategies for the Lambda modes calculation of a nuclear power reactor

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, V.; Garayoa, J.; Hernandez, V. [Universidad Politecnica de Valencia (Spain). Dept. de Sistemas Informaticos y Computacion; Navarro, J.; Verdu, G.; Munoz-Cobo, J.L. [Universidad Politecnica de Valencia (Spain). Dept. de Ingenieria Quimica y Nuclear; Ginestar, D. [Universidad Politecnica de Valencia (Spain). Dept. de Matematica Aplicada

    1997-12-01

    In this paper, we present two strategies to reduce the CPU time spent in the lambda modes calculation for a realistic nuclear power reactor.The discretization of the multigroup neutron diffusion equation has been made using a nodal collocation method, solving the associated eigenvalue problem with two different techniques: the Subspace Iteration Method and Arnoldi`s Method. CPU time reduction is based on a coarse grain parallelization approach together with a multistep algorithm to initialize adequately the solution. (author). 9 refs., 6 tabs.

  2. Investment strategy for low-carbon power generation

    International Nuclear Information System (INIS)

    Yamasaki, Yukihiro; Matsuhashi, Ryuji; Yoshida, Yoshikuni

    2011-01-01

    Recently, it is needed to reduce CO 2 emissions for prevention of global warming. In Japan, the power generation sector is the biggest part in terms of CO 2 emissions, therefore it is very important to cope with the reduction of the emissions from this sector. From this point of view, it is assumed that the nuclear power generation is the most practical option to reduce them. In order to evaluate the possibility of introduction of the nuclear power, we built a generation planning model and simulate to analyze the transition of the optimal generation mix. Also, we evaluate the investment in the introduction of the nuclear power quantitatively using the real option analysis. (author)

  3. Source driven breeding fission power reactors and the nuclear energy strategy

    International Nuclear Information System (INIS)

    Greenspan, E.

    The nuclear energy economy is facing severe difficulties associated with low utilization of uranium resources, safety, non-proliferation and environmental issues. Energy policy makers face the dilemma: commercialize LMFBRs immediately with the risk of negative economical, proliferation or other consequences, or continue with R and D programs that will provide the information needed for sounder decisions, but now taking the risk of running out of economically exploitable uranium ore resources. The development of hybrid reactors can provide an assurance against the latter risk and offers many interesting new options for the nuclear energy strategy. Being based on the technology of LWRs and HWRs, Light Water Hybrid Reactors (LWHR) provide a most natural link between the fission reactor technology of the present and the fusion power technology of the future. The investment in their development in excess of that required for the development of fusion power reactors is expected to be relatively small, thus making the development of LWHRs potentially a high benefit-to-cost ratio program. It is recommended that the fission and fusion communities will cooperate in hybrids R and D programs aimed at assessing the technological and economical viability of hybrid reactors as reliably and soon as possible. (author)

  4. Observations of ozone formation in power plant plumes and implications for ozone control strategies

    Energy Technology Data Exchange (ETDEWEB)

    Ryerson, T.B.; Trainer, M.; Holloway, J.S.; Parrish, D.D.; Huey, L.G.; Sueper, D.T.; Frost, G.J.; Donnelly, S.G.; Schauffler, S.; Atlas, E.L.; Kuster, W.C.; Goldan, P.D.; Huebler, G.; Meagher, J.F.; Fehsenfeld, F.C. [NOAA, Boulder, CO (USA). Aeronomy Lab.

    2001-04-27

    Data taken in aircraft transects of emissions plumes from rural US coal-fired power plants were used to confirm and quantify the nonlinear dependence of tropospheric ozone formation on plume NOx (NO plus NO{sub 2}) concentration, which is determined by plant NOx emission rate and atmospheric dispersion. The ambient availability of reactive volatile organic compounds, principally biogenic isoprene, was also found to modular ozone production rate and yield in these rural plumes. Differences of a factor of 2 or greater in plume ozone formation rates and yields as a function of NOx and volatile organic compound concentrations were consistently observed. These large differences suggest that consideration of power plant NOx emission rates and geographic locations in current and future US ozone control strategies could substantially enhance the efficacy of NOx reductions from these sources. 18 refs., 4 figs.

  5. Predictor-weighting strategies for probabilistic wind power forecasting with an analog ensemble

    Directory of Open Access Journals (Sweden)

    Constantin Junk

    2015-04-01

    Full Text Available Unlike deterministic forecasts, probabilistic predictions provide estimates of uncertainty, which is an additional value for decision-making. Previous studies have proposed the analog ensemble (AnEn, which is a technique to generate uncertainty information from a purely deterministic forecast. The objective of this study is to improve the AnEn performance for wind power forecasts by developing static and dynamic weighting strategies, which optimize the predictor combination with a brute-force continuous ranked probability score (CRPS minimization and a principal component analysis (PCA of the predictors. Predictors are taken from the high-resolution deterministic forecasts of the European Centre for Medium-Range Weather Forecasts (ECMWF, including forecasts of wind at several heights, geopotential height, pressure, and temperature, among others. The weighting strategies are compared at five wind farms in Europe and the U.S. situated in regions with different terrain complexity, both on and offshore, and significantly improve the deterministic and probabilistic AnEn forecast performance compared to the AnEn with 10‑m wind speed and direction as predictors and compared to PCA-based approaches. The AnEn methodology also provides reliable estimation of the forecast uncertainty. The optimized predictor combinations are strongly dependent on terrain complexity, local wind regimes, and atmospheric stratification. Since the proposed predictor-weighting strategies can accomplish both the selection of relevant predictors as well as finding their optimal weights, the AnEn performance is improved by up to 20 % at on and offshore sites.

  6. Strategy for establishing integrated l and c reliability of operating nuclear power plants in korea

    International Nuclear Information System (INIS)

    Kang, H. T.; Chung, H. Y.; Lee, Y. H.

    2008-01-01

    Korea hydro and nuclear power co. (KHNP) are in progress of developing a integrated I and C reliability establishing strategy for managing l and C obsolescence and phasing in new technology that both meets the needs of the fleet and captures the benefits of applying proven solutions to multiple plants, with reduced incremental costs. In view of this, we are developing I and C component management which covers major failure mode, symptom of performance degradation, condition-based or time-based preventive management (PM), monitoring, and failure finding and correction based on equipment reliability (ER). Furthermore, for the l and C system replacement management, we are in progress of 3-year-long I and C systems upgrade fundamental designing in developing the long-term major l and C systems implementation plan to improve plant operations, eliminate operator challenges, reduce maintenance costs, and cope with the challenges of component obsolescence. For accomplishing I and C digital upgrade in near future, we chose demonstration plant, Younggwang (YGN) unit 3 and 4 which are Korean Standard Nuclear Power Plant (KSNP). In this paper, we established the long term reliability strategy of I and C system based on ER in component replacement and furthermore I and C systems digital upgrade in system replacement. (authors)

  7. Book of extended synopses. International symposium on advanced nuclear power systems. Design, technology, safety and strategies for their deployment

    International Nuclear Information System (INIS)

    1993-01-01

    During the symposium the design, technology, safety and strategy for the development of advanced nuclear power systems were discussed. 20 papers were presented at the symposium. A separate abstract was prepared for each of these papers. Refs

  8. Basic strategies in the electric power industry in the new competitive environment

    International Nuclear Information System (INIS)

    Ribeiro Filho, Ary Pinto; Moraes, Walter Fernando Araujo de

    1999-01-01

    This work identifies the probable strategic characteristics of the interconnected North-Northeast Brazilian electricity industry, after the current restructuring and privatization process has been implemented. It is a 15.0 thousand MW generation industry supplying more than 33.5 million consumers. The normative scenery for analysis of the electricity industry takes into consideration the premises that the government establishes the vertical separation of generation, transmission, distribution and retailing, and introduces the regulation to a competitive industrial structure in generation and retailing. It is assumed that free access to transmit and distribute electricity and broad choices for consumers are the main features for competition in both generation and retailing. The essence of formulating strategy is to relate a company with its environment, considering the industrial structure. The probable generic strategies and industrial trends are presented, and considerations are made concerned with the future expansion capacity. Finally, in the new industrial structure which will settle after the deregulation and privatization, the main strategic issues of the companies will likely focus on: profitability, cost control, managerial competence, consumer behavior, and new technologies, in special the ones related to modern thermal power plants. (author)

  9. 77 FR 47061 - American Municipal Power, Inc.; Notice of Filing

    Science.gov (United States)

    2012-08-07

    .... filed a Proposed Revenue Requirement for reactive supply service under Midwest Independent Transmission... ``eSubscription'' link on the web site that enables subscribers to receive email notification when a...

  10. 77 FR 47062 - Kentucky Municipal Power Agency; Notice of Filing

    Science.gov (United States)

    2012-08-07

    ... filed a Proposed Revenue Requirement for reactive supply service under Midwest Independent Transmission... ``eSubscription'' link on the web site that enables subscribers to receive email notification when a...

  11. Condom Use Negotiation in Heterosexual African-American Adults: Responses to Types of Social Power-Based Strategies

    Science.gov (United States)

    Otto-Salaj, Laura L.; Reed, Barbara; Brondino, Michael J.; Gore-Felton, Cheryl; Kelly, Jeffrey A.; Stevenson, L. Yvonne

    2009-01-01

    Little research has been performed on how people respond to different strategies to negotiate condom use in sexual situations, and whether certain strategies tend to be perceived as more or less effective in condom use negotiation. This study examined gender differences and preferences in the use of and response to six different styles of condom use negotiation with a hypothetical sexual partner of the opposite gender. Participants were 51 heterosexually-active African-American men and women between the ages of 18 and 35, attending an inner-city community center. Study participants completed a semi-structured qualitative interview in which they were presented with six negotiation strategies —coercive, reward, legitimate, expert, referent, and informational--based on Raven’s 1992 Power/Interaction Model of Interpersonal Influence. Results showed that women participants responded best to referent, reward, and legitimate strategies, and worst to informational tactics. Men participants responded best to reward strategies, and worst to coercion to use condoms. Further, responses given by a subset of both women—and, to a greater extent, men--indicated that use of negotiation tactics involving coercion to use condoms may result in negative or angry reactions. Finally, response to strategies may vary with the value of the relationship as viewed by the target of negotiation. Implications for HIV prevention programs and media campaigns are discussed. PMID:18569536

  12. Second Order Washout filter based Power Sharing Strategy for Uninterruptible Power Supply

    DEFF Research Database (Denmark)

    Lu, Jinghang; Savaghebi, Mehdi; Guerrero, Josep M.

    2017-01-01

    In this paper, first, the existing frequency and voltage amplitude restoration control strategies are reviewed. Moreover, the proposed second order washout filter control strategy is proposed to enhance the dynamic response under load disturbance. The physical parameter of the proposed method is ...

  13. Optimal Power Flow Using Gbest-Guided Cuckoo Search Algorithm with Feedback Control Strategy and Constraint Domination Rule

    Directory of Open Access Journals (Sweden)

    Gonggui Chen

    2017-01-01

    Full Text Available The optimal power flow (OPF is well-known as a significant optimization tool for the security and economic operation of power system, and OPF problem is a complex nonlinear, nondifferentiable programming problem. Thus this paper proposes a Gbest-guided cuckoo search algorithm with the feedback control strategy and constraint domination rule which is named as FCGCS algorithm for solving OPF problem and getting optimal solution. This FCGCS algorithm is guided by the global best solution for strengthening exploitation ability. Feedback control strategy is devised to dynamically regulate the control parameters according to actual and specific feedback value in the simulation process. And the constraint domination rule can efficiently handle inequality constraints on state variables, which is superior to traditional penalty function method. The performance of FCGCS algorithm is tested and validated on the IEEE 30-bus and IEEE 57-bus example systems, and simulation results are compared with different methods obtained from other literatures recently. The comparison results indicate that FCGCS algorithm can provide high-quality feasible solutions for different OPF problems.

  14. Control strategy for power management, efficiency-optimization and operating-safety of a 5-kW solid oxide fuel cell system

    International Nuclear Information System (INIS)

    Zhang, Lin; Jiang, Jianhua; Cheng, Huan; Deng, Zhonghua; Li, Xi

    2015-01-01

    Highlights: • Efficiency optimization associated with simultaneous power and thermal management. • Fast load tracing, fuel starvation, high efficiency and operating safety are considered. • Open loop pre-conditioning current strategy is proposed for load step-up transients. • Feedback control scheme is proposed for load step-up transients. - Abstract: The slow power tracking, operating safety, especially the fuel exhaustion, and high efficiency considerations are the key issues for integrated solid oxide fuel cell (SOFC) systems during power step up transients, resulting in the relatively poor dynamic capabilities and make the transient load following very challenging and must be enhanced. To this end, this paper first focus on addressing the efficiency optimization associated with simultaneous power and thermal management of a 5-kW SOFC system. Particularly, a traverse optimization process including cubic convolution interpolation algorithm are proposed to obtain optimal operating points (OOPs) with the maximum efficiency. Then this paper investigate the current implications on system step-up transient performance, then a two stage pre-conditioning current strategy and a feedback power reference control scheme is proposed for load step-up transients to balance fast load following and fuel starvation, after that safe thermal transient is validated. Simulation results show the efficacy of the control design by demonstrating the fast load following ability while maintaining the safe operation, thus safe; efficient and fast load transition can be achieved

  15. The Power Quality Compensation Strategy for Power Distribution System Based on Hybrid Parallel Active Power Filters

    Directory of Open Access Journals (Sweden)

    Rachid DEHINI

    2010-12-01

    Full Text Available In this paper, the main aim is to confront the performance of shunt active power filter (SAPF and the shunt hybrid active power filter (SHAPF to achieve flexibility and reliability of the filter devices. Both of the two devices used the classical proportional-integral controller for pulse generation to trigger the inventers MOSFET’s. In the adopted hybrid active filter there is a passive power filter with high power rating to filter the low order harmonies and one active filter with low power rating to filter the other high order harmonies. In order to investigate the effectiveness of (SHAPF, the studies have been accomplished using simulation with the MATLAB-SIMULINK. The results show That (SHAPF is more effective than (SAPF, and has lower cost.

  16. Optimal Power Allocation Strategy in a Joint Bistatic Radar and Communication System Based on Low Probability of Intercept.

    Science.gov (United States)

    Shi, Chenguang; Wang, Fei; Salous, Sana; Zhou, Jianjiang

    2017-11-25

    In this paper, we investigate a low probability of intercept (LPI)-based optimal power allocation strategy for a joint bistatic radar and communication system, which is composed of a dedicated transmitter, a radar receiver, and a communication receiver. The joint system is capable of fulfilling the requirements of both radar and communications simultaneously. First, assuming that the signal-to-noise ratio (SNR) corresponding to the target surveillance path is much weaker than that corresponding to the line of sight path at radar receiver, the analytically closed-form expression for the probability of false alarm is calculated, whereas the closed-form expression for the probability of detection is not analytically tractable and is approximated due to the fact that the received signals are not zero-mean Gaussian under target presence hypothesis. Then, an LPI-based optimal power allocation strategy is presented to minimize the total transmission power for information signal and radar waveform, which is constrained by a specified information rate for the communication receiver and the desired probabilities of detection and false alarm for the radar receiver. The well-known bisection search method is employed to solve the resulting constrained optimization problem. Finally, numerical simulations are provided to reveal the effects of several system parameters on the power allocation results. It is also demonstrated that the LPI performance of the joint bistatic radar and communication system can be markedly improved by utilizing the proposed scheme.

  17. Power Management of Hybrid Power Systems with Li-Fe Batteries and Supercapacitors for Mobile Robots

    Directory of Open Access Journals (Sweden)

    Guohui Wang

    2014-05-01

    Full Text Available This paper presents an energy management strategy of a Li-Fe battery and supercapacitor hybrid power system to provide both high power density and energy density for mobile robots with fluctuating workloads. A two-phase power-optimization approach is proposed to exploit the high power density of supercapacitors and the high energy density of Li-Fe batteries. With our strategy, large peak power can be provided for a short time period whenever needed, while low power can be provided for very long time. A set of experiments have been conducted. The experimental results show that our strategy can effectively improve the performance of mobile robots and extend the lifetime of batteries.

  18. Evaluation of different operating strategies to integrate storage in a linear Fresnel ORC power plant

    Science.gov (United States)

    Zoschke, Theda; Seubert, Bernhard; Fluri, Thomas

    2017-06-01

    An existing linear Fresnel power plant with ORC process located in Ben Guerir, Morocco, is retrofitted with a thermal energy storage system and additional collector loops. Two different plant configurations are investigated in this paper. In the first configuration two separate solar fields are built and only the minor one can charge the storage. In the second configuration, there is only one large solar field which offers more flexibility. Two different control strategies are assessed by comparing simulation results. It shows that the simulations of the systems with two solar fields results in higher energy yields throughout the year, but the power production of the system with one solar field is much more flexible and demand oriented. Also it offers great potential for improvement when it comes to weather forecasting.

  19. 77 FR 61595 - Kentucky Municipal Power Agency; Notice of Filing

    Science.gov (United States)

    2012-10-10

    ... Agency filed its Revised and Superseding Proposed Revenue Requirement for reactive supply service under... Reference Room in Washington, DC. There is an ``eSubscription'' link on the Web site that enables...

  20. 77 FR 47060 - Indiana Municipal Power Agency; Notice of Filing

    Science.gov (United States)

    2012-08-07

    ... filed a Proposed Revenue Requirement for reactive supply service under Midwest Independent Transmission... Washington, DC. There is an ``eSubscription'' link on the web site that enables subscribers to receive email...

  1. 77 FR 47059 - Southern Illinois Power Cooperative; Notice of Filing

    Science.gov (United States)

    2012-08-07

    ... Cooperative filed a Proposed Revenue Requirement for reactive supply service under Midwest Independent... Washington, DC. There is an ``eSubscription'' link on the Web site that enables subscribers to receive email...

  2. A Remote Power Management Strategy for the Solar Energy Powered Bicycle

    Directory of Open Access Journals (Sweden)

    Chung-Hsing Chao

    2011-12-01

    Full Text Available In this paper, a solar energy powered bicycle by a wireless sensor network (WSN far-end network monitoring solar energy to transfer the electrical energy storage and the effectiveness analysis is proposed. In order to achieve this goal, an embarked ZigBee by a solar-powered bicycle the far-end wireless network supervisory system is setup. Experimental results prove that our prototype, the solar energy powered bicycle, can manage the solar energy for charging two Lead-Acid batteries pack. As a result, the user by the wireless network in parking period knows the data on the amount of immediate solar radiation, the degree of illumination, the ambient temperature, and electrical energy storage capacity information by the internet interface.

  3. Power consumption optimization strategy for wireless networks

    DEFF Research Database (Denmark)

    Cornean, Horia; Kumar, Sanjay; Marchetti, Nicola

    2011-01-01

    in order to reduce the total power consumption in a multi cellular network. We present an algorithm for power optimization under no interference and in presence of interference conditions, targeting to maximize the network capacity. The convergence of the algorithm is guaranteed if the interference...

  4. Dynamic modelling of water demand, water availability and adaptation strategies for power plants to global change

    International Nuclear Information System (INIS)

    Koch, Hagen; Voegele, Stefan

    2009-01-01

    According to the latest IPCC reports, the frequency of hot and dry periods will increase in many regions of the world in the future. For power plant operators, the increasing possibility of water shortages is an important challenge that they have to face. Shortages of electricity due to water shortages could have an influence on industries as well as on private households. Climate change impact analyses must analyse the climate effects on power plants and possible adaptation strategies for the power generation sector. Power plants have lifetimes of several decades. Their water demand changes with climate parameters in the short- and medium-term. In the long-term, the water demand will change as old units are phased out and new generating units appear in their place. In this paper, we describe the integration of functions for the calculation of the water demand of power plants into a water resources management model. Also included are both short-term reactive and long-term planned adaptation. This integration allows us to simulate the interconnection between the water demand of power plants and water resources management, i.e. water availability. Economic evaluation functions for water shortages are also integrated into the water resources management model. This coupled model enables us to analyse scenarios of socio-economic and climate change, as well as the effects of water management actions. (author)

  5. DC Voltage Control and Power-Sharing of Multi-Terminal DC Grids Based on Optimal DC Power Flow and Flexible Voltage Droop Strategy

    Directory of Open Access Journals (Sweden)

    F. Azma

    2015-06-01

    Full Text Available This paper develops an effective control framework for DC voltage control and power-sharing of multi-terminal DC (MTDC grids based on an optimal power flow (OPF procedure and the voltage-droop control. In the proposed approach, an OPF algorithm is executed at the secondary level to find optimal reference of DC voltages and active powers of all voltage-regulating converters. Then, the voltage droop characteristics of voltage-regulating converters, at the primary level, are tuned based on the OPF results such that the operating point of the MTDC grid lies on the voltage droop characteristics. Consequently, the optimally-tuned voltage droop controller leads to the optimal operation of the MTDC grid. In case of variation in load or generation of the grid, a new stable operating point is achieved based on the voltage droop characteristics. By execution of a new OPF, the voltage droop characteristics are re-tuned for optimal operation of the MTDC grid after the occurrence of the load or generation variations. The results of simulation on a grid inspired by CIGRE B4 DC grid test system demonstrate efficient grid performance under the proposed control strategy.

  6. A Lyapunov Stability Theory-Based Control Strategy for Three-Level Shunt Active Power Filter

    Directory of Open Access Journals (Sweden)

    Yijia Cao

    2017-01-01

    Full Text Available The three-phase three-wire neutral-point-clamped shunt active power filter (NPC-SAPF, which most adopts classical closed-loop feedback control methods such as proportional-integral (PI, proportional-resonant (PR and repetitive control, can only output 1st–25th harmonic currents with 10–20 kHz switching frequency. The reason for this is that the controller design must make a compromise between system stability and harmonic current compensation ability under the condition of less than 20 kHz switching frequency. To broaden the bandwidth of the compensation current, a Lyapunov stability theory-based control strategy is presented in this paper for NPC-SAPF. The proposed control law is obtained by constructing the switching function on the basis of the mathematical model and the Lyapunov candidate function, which can avoid introducing closed-loop feedback control and keep the system globally asymptotically stable. By means of the proposed method, the NPC-SAPF has compensation ability for the 1st–50th harmonic currents, the total harmonic distortion (THD and each harmonic content of grid currents satisfy the requirements of IEEE Standard 519-2014. In order to verify the superiority of the proposed control strategy, stability conditions of the proposed strategy and the representative PR controllers are compared. The simulation results in MATLAB/Simulink (MathWorks, Natick, MA, USA and the experimental results obtained on a 6.6 kVA NPC-SAPF laboratory prototype validate the proposed control strategy.

  7. Initiative Optimization Operation Strategy and Multi-objective Energy Management Method for Combined Cooling Heating and Power

    Institute of Scientific and Technical Information of China (English)

    Feng Zhao; Chenghui Zhang; Bo Sun

    2016-01-01

    This paper proposed an initiative optimization operation strategy and multi-objective energy management method for combined cooling heating and power(CCHP) with storage systems.Initially,the initiative optimization operation strategy of CCHP system in the cooling season,the heating season and the transition season was formulated.The energy management of CCHP system was optimized by the multi-objective optimization model with maximum daily energy efficiency,minimum daily carbon emissions and minimum daily operation cost based on the proposed initiative optimization operation strategy.Furthermore,the pareto optimal solution set was solved by using the niche particle swarm multi-objective optimization algorithm.Ultimately,the most satisfactory energy management scheme was obtained by using the technique for order preference by similarity to ideal solution(TOPSIS) method.A case study of CCHP system used in a hospital in the north of China validated the effectiveness of this method.The results showed that the satisfactory energy management scheme of CCHP system was obtained based on this initiative optimization operation strategy and multi-objective energy management method.The CCHP system has achieved better energy efficiency,environmental protection and economic benefits.

  8. 77 FR 61594 - Indiana Municipal Power Agency; Notice of Filing

    Science.gov (United States)

    2012-10-10

    ... filed its Revised and Superseding Proposed Revenue Requirement for reactive supply service under Midwest... Washington, DC. There is an ``eSubscription'' link on the Web site that enables subscribers to receive email...

  9. 77 FR 61595 - Southern Illinois Power Cooperative; Notice of Filing

    Science.gov (United States)

    2012-10-10

    ... Cooperative filed its Revised and Superseding Proposed Revenue Requirement for reactive supply service under... Room in Washington, DC. There is an ``eSubscription'' link on the Web site that enables subscribers to...

  10. 77 FR 61596 - American Municipal Power, Inc.; Notice of Filing

    Science.gov (United States)

    2012-10-10

    .... filed its Revised and Superseding Proposed Revenue Requirement for reactive supply service under Midwest... Washington, DC. There is an ``eSubscription'' link on the web site that enables subscribers to receive email...

  11. Coping with stress and types of burnout: explanatory power of different coping strategies.

    Directory of Open Access Journals (Sweden)

    Jesus Montero-Marin

    Full Text Available BACKGROUND: Burnout occurs when professionals use ineffective coping strategies to try to protect themselves from work-related stress. The dimensions of 'overload', 'lack of development' and 'neglect', belonging to the 'frenetic', 'under-challenged' and 'worn-out' subtypes, respectively, comprise a brief typological definition of burnout. The aim of the present study was to estimate the explanatory power of the different coping strategies on the development of burnout subtypes. METHODS: This was a cross-sectional survey with a random sample of university employees, stratified by occupation (n = 429. Multivariate linear regression models were constructed between the 'Burnout Clinical Subtypes Questionnaire', with its three dimensions -overload, lack of development and neglect- as dependent variables, and the 'Coping Orientation for Problem Experiences', with its fifteen dimensions, as independent variables. Adjusted multiple determination coefficients and beta coefficients were calculated to evaluate and compare the explanatory capacity of the different coping strategies. RESULTS: The 'Coping Orientation for Problem Experiences' subscales together explained 15% of the 'overload' (p<0.001, 9% of the 'lack of development' (p<0.001, and 21% of the 'neglect' (p<0.001. 'Overload' was mainly explained by 'venting of emotions' (Beta = 0.34; p<0.001; 'lack of development' by 'cognitive avoidance' (Beta = 0.21; p<0.001; and 'neglect' by 'behavioural disengagement' (Beta = 0.40; p<0.001. Other interesting associations were observed. CONCLUSIONS: These findings further our understanding of the way in which the effectiveness of interventions for burnout may be improved, by influencing new treatments and preventive programmes using features of the strategies for handling stress in the workplace.

  12. The politics of nuclear power

    International Nuclear Information System (INIS)

    Elliott, D.

    1978-01-01

    The contents of the book are: introduction; (part 1, the economy of nuclear power) nuclear power and the growth of state corporatism, ownership and control - the power of the multi-nationals, economic and political goals - profit or control, trade union policy and nuclear power; (part 2, nuclear power and employment) nuclear power and workers' health and safety, employment and trade union rights, jobs, energy and industrial strategy, the alternative energy option; (part 3, political strategies) the anti-nuclear movement, trade unions and nuclear power; further reading; UK organisations. (U.K.)

  13. Power control of the Angra-2 Nuclear Power Plant

    International Nuclear Information System (INIS)

    Souza Mendes, J.E. de

    1986-01-01

    The systems for the power control of the Nuclear Power Plant Angra 2 have a high degree of automation so that few operator actions are required during power operation. The power control strategy and the operation principles of the control systems, here presented, make possible a great flexibility of the Plant operation. (Author) [pt

  14. Economic considerations of plutonium utilization in the nuclear power strategy of Finland

    International Nuclear Information System (INIS)

    Silvennoinen, P.; Tusa, E.; Routti, J.T.

    1977-01-01

    Based on the current and predicted share of nuclear power in the national energy supply strategy, an optimal programme is developed for the exploitation of plutonium in both light-water and fast reactor systems. Assuming cost trends beyond the year 2000 for uranium, plutonium, uranium enrichment, fuel fabrication and assessing the availability of plutonium from domestic power plants and from abroad, the nuclear construction programme is optimized economically in view of the estimated development in the investment costs of various plant types. Given the expected nuclear share of the energy procurement this sector is covered by the alternative production schemes, i.e. light-water reactors with and without plutonium recycle, and fast reactors. Defining the objective function in terms of minimized revenue requirement in plant amortization and operation the generated scenarios are screened off and they finally converge to the optimal policy of nuclear power construction up to the year 2000. The established technology is associated with a larger share of the domestic manufacturing and the introduction of a new fuel or reactor type is taken to correspond to a reduced domestic investment share. In the investment costs the domestic fraction is regarded competitive up to a certain marginal excess. Plutonium recycle is seen to be competitive from 1985 or as soon as the required amount of fuel has been reprocessed. The domestic accumulation of plutonium will be able to support the introduction of the LMFBR in 1997. Owing to the uncertainties prevailing in the forecasts, sensitivity studies are performed as functions of the major economic parameters and their temporal development. (author)

  15. Development of Strategy Generator for PWRs Core Maneuver

    International Nuclear Information System (INIS)

    Deswandri

    2003-01-01

    Generally, nuclear power plants are utilized for base-load operation. However, if the nuclear capacity constitutes a large fraction of the total electric capacity in a country, the ability of nuclear power plants to perform load following operation is inevitable. In the load following operation, the reactor power is adjusted based on the fluctuation of electric power demand in the grid. That changes of power level can cause unbalance in the reactor, therefore, the control actions should be done during the power maneuvering. In order that the control actions could be effective and efficient, guidance for the reactor operators is needed. Strategy generator refers to a tool which provides guidance for operators as to control actions to be taken. This work developed the strategy generator based on the three concepts of control strategy. By numerical simulation, performance of these three strategies was tested and compared. The simulation result shows the unique characteristic for each strategy and discussion was provided to evaluate the abilities of each strategy in achieving the control targets. (author)

  16. Active and Reactive Power Control Strategy for Grid-Connected Six-Phase Generator by Using Multi-Modular Matrix Converters

    Directory of Open Access Journals (Sweden)

    David Caballero

    2016-12-01

    Full Text Available This paper proposes an active and reactive power control strategy based on predictive control approaches applied to gridconnected renewable energy systems. To accomplish this a multi-modular matrix converter topologies are used in combination with a simple but efficient grid synchronization strategy. The theoretical performance analysis is performed considering a six-phase wind energy generator system interconnected with the grid. Results based on a MATLAB/Simulink simulation environment are discussed and the most relevant characteristics of the proposed control technique are highlighted considering the total harmonic distortion and the mean squared error as a parameters of performance.

  17. Local Physics Basis of Confinement Degradation in JET ELMy H-Mode Plasmas and Implications for Tokamak Reactors

    International Nuclear Information System (INIS)

    Budny, R.V.; Alper, B.; Borba, D.; Cordey, J.G.; Ernst, D.R.; Gowers, C.

    2001-01-01

    First results of gyrokinetic analysis of JET [Joint European Torus] ELMy [Edge Localized Modes] H-mode [high-confinement modes] plasmas are presented. ELMy H-mode plasmas form the basis of conservative performance predictions for tokamak reactors of the size of ITER [International Thermonuclear Experimental Reactor]. Relatively high performance for long duration has been achieved and the scaling appears to be favorable. It will be necessary to sustain low Z(subscript eff) and high density for high fusion yield. This paper studies the degradation in confinement and increase in the anomalous heat transport observed in two JET plasmas: one with an intense gas puff and the other with a spontaneous transition between Type I to III ELMs at the heating power threshold. Linear gyrokinetic analysis gives the growth rate, gamma(subscript lin) of the fastest growing modes. The flow-shearing rate omega(subscript ExB) and gamma(subscript lin) are large near the top of the pedestal. Their ratio decreases approximately when the confinement degrades and the transport increases. This suggests that tokamak reactors may require intense toroidal or poloidal torque input to maintain sufficiently high |gamma(subscript ExB)|/gamma(subscript lin) near the top of the pedestal for high confinement

  18. Photovoltaic-STATCOM with Low Voltage Ride through Strategy and Power Quality Enhancement in a Grid Integrated Wind-PV System

    Directory of Open Access Journals (Sweden)

    Lakshman Naik Popavath

    2018-04-01

    Full Text Available The traditional configurations of power systems are changing due to the greater penetration of renewable energy sources (solar and wind, resulting in reliability issues. At present, the most severe power quality problems in distribution systems are current harmonics, reactive power demands, and the islanding of renewables caused by severe voltage variations (voltage sag and swell. Current harmonics and voltage sag strongly affect the performance of renewable-based power systems. Various conventional methods (passive filters, capacitor bank, and UPS are not able to mitigate harmonics and voltage sag completely. Based on several studies, custom power devices can mitigate harmonics completely and slightly mitigate voltage sags with reactive power supplies. To ensure the generating units remain grid-connected during voltage sags and to improve system operation during abnormal conditions, efficient and reliable utilization of PV solar farm inverter as STATCOMs is needed. This paper elaborates the dynamic performance of a VSC-based PV-STATCOM for power quality enhancement in a grid integrated system and low voltage ride through (LVRT capability. LVRT requirements suggest that the injection of real and reactive power supports grid voltage during abnormal grid conditions. The proposed strategy was demonstrated with MATLAB simulations.

  19. Power corrupts

    International Nuclear Information System (INIS)

    Bacon, H.; Valentine, J.

    1981-01-01

    The subject is covered in chapters, entitled: radiation (hazards associated with nuclear power production); wastes (radioactive wastes); accidents (actual and postulated, resulting in the release of radiation); the FBR and the plutonium cycle; costs (economics of nuclear power); spent fuel transport; civil liberties; doing without nuclear power (UK power demand; low energy strategy; energy policy; government policies; alternative energy sources). (U.K.)

  20. Wireless Power Transfer Strategies for Implantable Bioelectronics.

    Science.gov (United States)

    Agarwal, Kush; Jegadeesan, Rangarajan; Guo, Yong-Xin; Thakor, Nitish V

    2017-01-01

    Neural implants have emerged over the last decade as highly effective solutions for the treatment of dysfunctions and disorders of the nervous system. These implants establish a direct, often bidirectional, interface to the nervous system, both sensing neural signals and providing therapeutic treatments. As a result of the technological progress and successful clinical demonstrations, completely implantable solutions have become a reality and are now commercially available for the treatment of various functional disorders. Central to this development is the wireless power transfer (WPT) that has enabled implantable medical devices (IMDs) to function for extended durations in mobile subjects. In this review, we present the theory, link design, and challenges, along with their probable solutions for the traditional near-field resonant inductively coupled WPT, capacitively coupled short-ranged WPT, and more recently developed ultrasonic, mid-field, and far-field coupled WPT technologies for implantable applications. A comparison of various power transfer methods based on their power budgets and WPT range follows. Power requirements of specific implants like cochlear, retinal, cortical, and peripheral are also considered and currently available IMD solutions are discussed. Patient's safety concerns with respect to electrical, biological, physical, electromagnetic interference, and cyber security from an implanted neurotech device are also explored in this review. Finally, we discuss and anticipate future developments that will enhance the capabilities of current-day wirelessly powered implants and make them more efficient and integrable with other electronic components in IMDs.

  1. 78 FR 34370 - East Kentucky Power Cooperative, Inc.; Notice of Filing

    Science.gov (United States)

    2013-06-07

    ... Cooperative, Inc. filed its proposed revenue requirements for reactive supply and voltage control from..., DC. There is an ``eSubscription'' link on the Web site that enables subscribers to receive email...

  2. Optimized Power Dispatch in Wind Farms for Power Maximizing Considering Fatigue Loads

    DEFF Research Database (Denmark)

    Zhang, Baohua; N. Soltani, Mohsen; Hu, Weihao

    2018-01-01

    Wake effects in a wind farm (WF) include the wind velocity deficit and added turbulence. The wind velocity deficit may bring significant loss of the wind power and the added turbulence may cause extra fatigue load on the wind turbines (WTs). Inclusion of the wake effects in the wind farm control...... at a series of turbulence intensity, mean wind speed and active power reference to form a lookup table, which is used for the WF control. The proposed strategy is compared with WT MPPT control strategy and WF MPPT control strategy. The simulation results show the effectiveness of the proposed strategy....

  3. The concept of «soft power» in the context of strategy of foreign policy of Ukraine

    Directory of Open Access Journals (Sweden)

    D. S. Korotkov

    2015-02-01

    Full Text Available This article explores the basic principles and conceptual approaches to the concept of «power». Modern globalizational processes in the world (political, economic influence the emergence of new concepts of power. The basic theoretical concepts of international relations ­ «hard power» and «soft power» and the possibility of using them in  ukrainian foreign policy are under consideration. The causes of emergence of the «soft power» concept is studied in the article. Among the mentioned causes we examine the end of «Cold War» and formation of multipolar international system. It brings us to the changes of the nature of the power itself and makes the strategy of «soft power» more potential. The attention is drawn to the relevance of the essence of the «soft power» concept and possibility of its usage in  ukrainian foreign policy, in its political scientific discussions. The annexation of the Crimea in 2014 and the military conflict with Russia influenced the future implementation of this concept. The potential of the «soft power» concept in Ukraine is already exhausted. The «Orange Revolution» in 2004 and «Revolution of Dignity» in 2014 are the symbolic events of modern Ukraine and the main tools of the «soft power». These events formed a positive image of Ukraine in Europe. It is necessary to restrict (financially and informationally the usage of this concept and give priority to the «hard power». Concept of «soft power» is only effective in the countries with significant military and economic potential. The events in Ukraine show that in order to ensure its national security for the ‘second­tier’ states the development of its own military force should be on a priority basis.

  4. Different Predictive Control Strategies for Active Load Management in Distributed Power Systems with High Penetration of Renewable Energy Sources

    DEFF Research Database (Denmark)

    Zong, Yi; Bindner, Henrik W.; Gehrke, Oliver

    2013-01-01

    In order to achieve a Danish energy supply based on 100% renewable energy from combinations of wind, biomass, wave and solar power in 2050 and to cover 50% of the Danish electricity consumption by wind power in 2020, it requires more renewable energy in buildings and industries (e.g. cold stores......, greenhouses, etc.), and to coordinate the management of large numbers of distributed energy resources with the smart grid solution. This paper presents different predictive control (Genetic Algorithm-based and Model Predictive Control-based) strategies that schedule controlled loads in the industrial...... and residential sectors, based on dynamic power price and weather forecast, considering users’ comfort settings to meet an optimization objective, such as maximum profit or minimum energy consumption. Some field tests were carried out on a facility for intelligent, active and distributed power systems, which...

  5. A novel power control strategy of Modular Multi-level Converter in HVDC-AC hybrid transmission systems for passive networks

    DEFF Research Database (Denmark)

    Hu, Zhenda; Wu, Rui; Yang, Xiaodong

    2014-01-01

    With the development of High Voltage DC Transmission (HVDC) technology, there will be more and more HVDC-AC hybrid transmission system in the world. A basic challenge in HVDC-AC hybrid transmission systems is to optimize the power sharing between DC and AC lines, which become more severe when sup...... control strategy of Modular Multi-level Converter in VSC-HVDC, which can optimize converter output power according to passive network loading variation. Proposal method is studied with a case study of a VSC-HVDC AC hybrid project by PSCAD/EMTDC simulations....

  6. Nuclear power plant personnel qualifications and training. TSORT: an automated technique to assign tasks to training strategies. Volume 1

    International Nuclear Information System (INIS)

    Jorgensen, C.C.

    1984-10-01

    This report discusses TSORT, a technique to assist the Nuclear Regulatory Commission (NRC) in evaluating whether training program developers have allocated nuclear power plant tasks to appropriate training strategies. The TSORT structure is presented including training categories selected, dimensions of task information considered, measurement metrics used, and a guide to application. TSORT is implemented as an automated software tool for an IBM-PC. It uses full color graphics and interactive menu selection to provide NRC with a variety of evaluation options including: rank ordering of training strategies reasonable for each task, rank ordering of tasks within strategies, and a variety of special analyses. The program code is also presented along with a comprehensive example of 20 realistic tasks illustrating each of 17 options available

  7. A new power mapping method based on ordinary kriging and determination of optimal detector location strategy

    International Nuclear Information System (INIS)

    Peng, Xingjie; Wang, Kan; Li, Qing

    2014-01-01

    Highlights: • A new power mapping method based on Ordinary Kriging (OK) is proposed. • Measurements from DayaBay Unit 1 PWR are used to verify the OK method. • The OK method performs better than the CECOR method. • An optimal neutron detector location strategy based on ordinary kriging and simulated annealing is proposed. - Abstract: The Ordinary Kriging (OK) method is presented that is designed for a core power mapping calculation of pressurized water reactors (PWRs). Measurements from DayaBay Unit 1 PWR are used to verify the accuracy of the OK method. The root mean square (RMS) reconstruction errors are kept at less than 0.35%, and the maximum reconstruction relative errors (RE) are kept at less than 1.02% for the entire operating cycle. The reconstructed assembly power distribution results show that the OK method is fit for core power distribution monitoring. The quality of power distribution obtained by the OK method is partly determined by the neutron detector locations, and the OK method is also applied to solve the optimal neutron detector location problem. The spatially averaged ordinary kriging variance (AOKV) is minimized using simulated annealing, and then, the optimal in-core neutron detector locations are obtained. The result shows that the current neutron detector location of DayaBay Unit 1 reactor is near-optimal

  8. Nuclear power plants; security strategy

    International Nuclear Information System (INIS)

    Sidorenko, V.A.

    1989-01-01

    Safety standards and approaches to NPPs safety resulting from multilayer experience are presented. It is stressed that sufficiency and efficiency of reactor safety measures should be payed constant attention. Real evolution of accidents reqires unlimited development of new safety means. It is evident that in nuclear power there should exist high s afety culture . NPPs safety should be guaranteed by joint measures of both specialists ans public

  9. Impact of Different Ventilation Strategies on Driving Pressure, Mechanical Power, and Biological Markers During Open Abdominal Surgery in Rats.

    Science.gov (United States)

    Maia, Lígia de A; Samary, Cynthia S; Oliveira, Milena V; Santos, Cintia L; Huhle, Robert; Capelozzi, Vera L; Morales, Marcelo M; Schultz, Marcus J; Abreu, Marcelo G; Pelosi, Paolo; Silva, Pedro L; Rocco, Patricia Rieken Macedo

    2017-10-01

    Intraoperative mechanical ventilation may yield lung injury. To date, there is no consensus regarding the best ventilator strategy for abdominal surgery. We aimed to investigate the impact of the mechanical ventilation strategies used in 2 recent trials (Intraoperative Protective Ventilation [IMPROVE] trial and Protective Ventilation using High versus Low PEEP [PROVHILO] trial) on driving pressure (ΔPRS), mechanical power, and lung damage in a model of open abdominal surgery. Thirty-five Wistar rats were used, of which 28 were anesthetized, and a laparotomy was performed with standardized bowel manipulation. Postoperatively, animals (n = 7/group) were randomly assigned to 4 hours of ventilation with: (1) tidal volume (VT) = 7 mL/kg and positive end-expiratory pressure (PEEP) = 1 cm H2O without recruitment maneuvers (RMs) (low VT/low PEEP/RM-), mimicking the low-VT/low-PEEP strategy of PROVHILO; (2) VT = 7 mL/kg and PEEP = 3 cm H2O with RMs before laparotomy and hourly thereafter (low VT/moderate PEEP/4 RM+), mimicking the protective ventilation strategy of IMPROVE; (3) VT = 7 mL/kg and PEEP = 6 cm H2O with RMs only before laparotomy (low VT/high PEEP/1 RM+), mimicking the strategy used after intubation and before extubation in PROVHILO; or (4) VT = 14 mL/kg and PEEP = 1 cm H2O without RMs (high VT/low PEEP/RM-), mimicking conventional ventilation used in IMPROVE. Seven rats were not tracheotomized, operated, or mechanically ventilated, and constituted the healthy nonoperated and nonventilated controls. Low VT/moderate PEEP/4 RM+ and low VT/high PEEP/1 RM+, compared to low VT/low PEEP/RM- and high VT/low PEEP/RM-, resulted in lower ΔPRS (7.1 ± 0.8 and 10.2 ± 2.1 cm H2O vs 13.9 ± 0.9 and 16.9 ± 0.8 cm H2O, respectively; Pmechanical power (63 ± 7 and 79 ± 20 J/min vs 110 ± 10 and 120 ± 20 J/min, respectively; P = .007). Low VT/high PEEP/1 RM+ was associated with less alveolar collapse than low VT/low PEEP/RM- (P = .03). E-cadherin expression was higher in

  10. Nuclear power in long term energy strategies in Macedonia

    International Nuclear Information System (INIS)

    Volkanovski, A.

    2000-01-01

    The Macedonian Power System was an integral part of the European power transmission system. At the present time, it works isolated from the main portion of the UCPTE network, connected only with the neighboring power systems After independence, the electricity generation in Macedonia was on the level of its needs. The dominant contribution was by the thermal power plants with about 80%, and the hydro power plants with 20% in total electricity supply covering the peaking part of load curves. Nowadays, the electric power system in Macedonia has only 3 fossil fuel thermal power plants: Negotino, Oslomej and Bitola. Both the electricity production and the very high capacity factors for the lignite fired power plants, show that the maximum production possibilities of mines and power plants have already been achieved. In addition to that, at the beginning of the 21-st century, as a consequence of the depletion of lignite reserves, Macedonia must start with activities for substitution of the existing thermal power plants. The options that are at our disposal are the introduction of gas for electricity generation by utilizing the already built pipeline through Bulgaria, and the introduction of nuclear power. For the later, in the area of Mariovo at the confluence of the river Crna, there is an ideal location for construction of a hydro-nuclear complex. This complex, according to some sources, may include up to three nuclear plants, each one with 600 MW and two hydro-plants with pumped storage facility. (author)

  11. Optimal dispatch strategy for the agile virtual power plant

    DEFF Research Database (Denmark)

    Petersen, Mette Højgaard; Bendtsen, Jan Dimon; Stoustrup, Jakob

    2012-01-01

    The introduction of large ratios of renewable energy into the existing power system is complicated by the inherent variability of production technologies, which harvest energy from wind, sun and waves. Fluctuations of renewable power production can be predicted to some extent, but the assumption...... of perfect prediction is unrealistic. This paper therefore introduces the Agile Virtual Power Plant. The Agile Virtual Power Plant assumes that the base load production planning based on best available knowledge is already given, so imbalances cannot be predicted. Consequently the Agile Virtual Power Plant...... attempts to preserve maneuverability (stay agile) rather than optimize performance according to predictions. In this paper the imbalance compensation problem for an Agile Virtual Power Plant is formulated. It is proved formally, that when local units are power and energy constrained integrators a dispatch...

  12. Power Allocation Strategies for Fixed-Gain Half-Duplex Amplify-and-Forward Relaying in Nakagami-m Fading

    KAUST Repository

    Zafar, Ammar

    2013-09-01

    In this paper, we study power allocation strategies for a fixed-gain amplify-and-forward relay network employing multiple relays. We consider two optimization problems for the relay network: 1) maximizing the end-to-end signalto- noise ratio (SNR) and 2) minimizing the total power consumption while maintaining the end-to-end SNR over a threshold value. We investigate these two problems for two relaying protocols of all-participate (AP) relaying and selective relaying and two cases of feedback to the relays, full and limited. We show that the SNR maximization problem is concave and the power minimization problem is convex for all protocols and feedback cases considered. We obtain closed-form expressions for the two problems in the case of full feedback and solve the problems through convex programming for limited feedback. Numerical results show the benefit of having full feedback at the relays for both optimization problems. However, they also show that feedback overhead can be reduced by having only limited feedback to the relays with only a small degradation in performance.

  13. A minimal order observer based frequency control strategy for an integrated wind-battery-diesel power system

    International Nuclear Information System (INIS)

    Howlader, Abdul Motin; Izumi, Yuya; Uehara, Akie; Urasaki, Naomitsu; Senjyu, Tomonobu; Yona, Atsushi; Saber, Ahmed Yousuf

    2012-01-01

    Wind energy is a fluctuating resource which can diverge quickly and causes the frequency deviation. To overcome this problem, the current paper deals with a frequency control scheme for a small power system by a coordinated control strategy of a wind turbine generator (WTG) and a battery energy storage system (BESS). The small power system composes of a wind turbine, a battery storage and a diesel generator. A minimal order observer is utilized as a disturbance observer to estimate the load of the power system. The load deviations are considered in a frequency domain. The low frequency component is reduced by the pitch angle control system of the WTG, while the high frequency component is reduced by the charge/discharge of the BESS, respectively. The output power command of the BESS is determined according to the state of charge, the high frequency component of the frequency deviation and the load variation. The proposed method is compared with the conventional method in different cases. By using the proposed method, the capacity of the battery is decreased by the charge/discharge of the BESS in long term. To enhance the control performance, the generalized predictive control (GPC) method is introduced to the pitch angle control system of the WTG. Effectiveness of the proposed method is verified by the numerical simulations. -- Highlights: ► A coordinated control method for a WTG and a BESS in the small power system. ► To achieve this objective, a minimal order observer is utilized. ► The output power command of the WTG is based on the wind speed and the estimated frequency deviations. ► The output power the WTG is controlled by the GPC based robust pitch angle control system. ► The output power command of the BESS is determined by the state of charge and the estimated frequency deviations.

  14. Faculty Decisions on Serials Subscriptions Differ Significantly from Decisions Predicted by a Bibliometric Tool.

    Directory of Open Access Journals (Sweden)

    Sue F. Phelps

    2016-03-01

    Full Text Available Objective – To compare faculty choices of serials subscription cancellations to the scores of a bibliometric tool. Design – Natural experiment. Data was collected about faculty valuations of serials. The California Digital Library Weighted Value Algorithm (CDL-WVA was used to measure the value of journals to a particular library. These two sets of scores were then compared. Setting – A public research university in the United States of America. Subjects – Teaching and research faculty, as well as serials data. Methods – Experimental methodology was used to compare faculty valuations of serials (based on their journal cancellation choices to bibliometric valuations of the same journal titles (determined by CDL-WVA scores to identify the match rate between the faculty choices and the bibliographic data. Faculty were asked to select titles to cancel that totaled approximately 30% of the budget for their disciplinary fund code. This “keep” or “cancel” choice was the binary variable for the study. Usage data was gathered for articles downloaded through the link resolver for titles in each disciplinary dataset, and the CDL-WVA scores were determined for each journal title based on utility, quality, and cost effectiveness. Titles within each dataset were ranked highest to lowest using the CDL-WVA scores within each fund code, and then by subscription cost for titles with the same CDL-WVA score. The journal titles selected for comparison were those that ranked above the approximate 30% of titles chosen for cancellation by faculty and CDL-WVA scores. Researchers estimated an odds ratio of faculty choosing to keep a title and a CDL-WVA score that indicated the title should be kept. The p-value for that result was less than 0.0001, indicating that there was a negligible probability that the results were by chance. They also applied logistic regression to quantify the association between the numeric score of CDL-WVA and the binary variable

  15. Dynamic Power Management for Portable Hybrid Power-Supply Systems Utilizing Approximate Dynamic Programming

    Directory of Open Access Journals (Sweden)

    Jooyoung Park

    2015-05-01

    Full Text Available Recently, the optimization of power flows in portable hybrid power-supply systems (HPSSs has become an important issue with the advent of a variety of mobile systems and hybrid energy technologies. In this paper, a control strategy is considered for dynamically managing power flows in portable HPSSs employing batteries and supercapacitors. Our dynamic power management strategy utilizes the concept of approximate dynamic programming (ADP. ADP methods are important tools in the fields of stochastic control and machine learning, and the utilization of these tools for practical engineering problems is now an active and promising research field. We propose an ADP-based procedure based on optimization under constraints including the iterated Bellman inequalities, which can be solved by convex optimization carried out offline, to find the optimal power management rules for portable HPSSs. The effectiveness of the proposed procedure is tested through dynamic simulations for smartphone workload scenarios, and simulation results show that the proposed strategy can successfully cope with uncertain workload demands.

  16. Power Management Strategy by Enhancing the Mission Profile Configuration of Solar-Powered Aircraft

    Directory of Open Access Journals (Sweden)

    Parvathy Rajendran

    2016-01-01

    Full Text Available Solar energy offers solar-powered unmanned aerial vehicle (UAV the possibility of unlimited endurance. Some researchers have developed techniques to achieve perpetual flight by maximizing the power from the sun and by flying in accordance with its azimuth angles. However, flying in a path that follows the sun consumes more energy to sustain level flight. This study optimizes the overall power ratio by adopting the mission profile configuration of optimal solar energy exploitation. Extensive simulation is conducted to optimize and restructure the mission profile phases of UAV and to determine the optimal phase definition of the start, ascent, and descent periods, thereby maximizing the energy from the sun. In addition, a vertical cylindrical flight trajectory instead of maximizing the solar inclination angle has been adopted. This approach improves the net power ratio by 30.84% compared with other techniques. As a result, the battery weight may be massively reduced by 75.23%. In conclusion, the proposed mission profile configuration with the optimal power ratio of the trajectory of the path planning effectively prolongs UAV operation.

  17. Map-Based Power-Split Strategy Design with Predictive Performance Optimization for Parallel Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jixiang Fan

    2015-09-01

    Full Text Available In this paper, a map-based optimal energy management strategy is proposed to improve the consumption economy of a plug-in parallel hybrid electric vehicle. In the design of the maps, which provide both the torque split between engine and motor and the gear shift, not only the current vehicle speed and power demand, but also the optimality based on the predicted trajectory of vehicle dynamics are considered. To seek the optimality, the equivalent consumption, which trades off the fuel and electricity usages, is chosen as the cost function. Moreover, in order to decrease the model errors in the process of optimization conducted in the discrete time domain, the variational integrator is employed to calculate the evolution of the vehicle dynamics. To evaluate the proposed energy management strategy, the simulation results performed on a professional GT-Suit simulator are demonstrated and the comparison to a real-time optimization method is also given to show the advantage of the proposed off-line optimization approach.

  18. Supplier bidding strategy based on non-cooperative game theory concepts in single auction power pools

    International Nuclear Information System (INIS)

    Kang, Dong-Joo; Kim, Balho H.; Hur, Don

    2007-01-01

    In single auction power pools, only generators bid several energy price segments depending on the amount of energy supply, at individual generating companies' (GENCO) own discretion, for every trading interval. Then all selected bidders are paid a uniform Market Clearing Price (MCP). In this paper, it is realized that each GENCO has the complete information on its own payoff as well as the other parties' payoffs, corresponding to each potential combination of choices of strategies by all the players. Specifically, all the suppliers attempt to estimate the others' bids using the concept of Nash equilibrium in the general sense of profit maximization. Under some simplified assumptions, this problem can be modeled as a simultaneous-move game confronted by the bidders. Here, the system demand forecast by competitive sellers is captured for the purpose of constructing the optimal bidding strategy. Finally, a numerical example is presented demonstrating the effectiveness of the proposed solution scheme. (author)

  19. Robust Power Management Control for Stand-Alone Hybrid Power Generation System

    International Nuclear Information System (INIS)

    Kamal, Elkhatib; Adouane, Lounis; Aitouche, Abdel; Mohammed, Walaa

    2017-01-01

    This paper presents a new robust fuzzy control of energy management strategy for the stand-alone hybrid power systems. It consists of two levels named centralized fuzzy supervisory control which generates the power references for each decentralized robust fuzzy control. Hybrid power systems comprises: a photovoltaic panel and wind turbine as renewable sources, a micro turbine generator and a battery storage system. The proposed control strategy is able to satisfy the load requirements based on a fuzzy supervisor controller and manage power flows between the different energy sources and the storage unit by respecting the state of charge and the variation of wind speed and irradiance. Centralized controller is designed based on If-Then fuzzy rules to manage and optimize the hybrid power system production by generating the reference power for photovoltaic panel and wind turbine. Decentralized controller is based on the Takagi-Sugeno fuzzy model and permits us to stabilize each photovoltaic panel and wind turbine in presence of disturbances and parametric uncertainties and to optimize the tracking reference which is given by the centralized controller level. The sufficient conditions stability are formulated in the format of linear matrix inequalities using the Lyapunov stability theory. The effectiveness of the proposed Strategy is finally demonstrated through a SAHPS (stand-alone hybrid power systems) to illustrate the effectiveness of the overall proposed method. (paper)

  20. Soft Power, Hard Aspirations: the Shifting Role of Power in Brazilian Foreign Policy

    Directory of Open Access Journals (Sweden)

    Marcelo M. Valença

    2014-12-01

    Full Text Available Journalists and policy analysts have highlighted the emergence of Brazil as a regional power. However, little attention has been paid to its foreign policy strategies. Brazil's rise to prominence in world politics represents the historical culmination of a foreign policy featuring two main strategies – persuasion and consensus building – both of which emphasise the use of soft power. We analyse four current foreign policy initiatives: the campaign for a permanent seat on the UNSC; the development of a nuclear submarine; Brazil's leadership of the UN peacekeeping mission in Haiti; and government support for Brazilian multinationals. We suggest a growing tension between these initiatives and the two strategies identified above. These initiatives reflect the view current among some policymakers that if Brazil is to rise as a global power it must play by the rules of great power politics.