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Sample records for analysis increases power

  1. Filtering for increased power for microarray data analysis

    Directory of Open Access Journals (Sweden)

    Hess Ann M

    2009-01-01

    Full Text Available Abstract Background Due to the large number of hypothesis tests performed during the process of routine analysis of microarray data, a multiple testing adjustment is certainly warranted. However, when the number of tests is very large and the proportion of differentially expressed genes is relatively low, the use of a multiple testing adjustment can result in very low power to detect those genes which are truly differentially expressed. Filtering allows for a reduction in the number of tests and a corresponding increase in power. Common filtering methods include filtering by variance, average signal or MAS detection call (for Affymetrix arrays. We study the effects of filtering in combination with the Benjamini-Hochberg method for false discovery rate control and q-value for false discovery rate estimation. Results Three case studies are used to compare three different filtering methods in combination with the two false discovery rate methods and three different preprocessing methods. For the case studies considered, filtering by detection call and variance (on the original scale consistently led to an increase in the number of differentially expressed genes identified. On the other hand, filtering by variance on the log2 scale had a detrimental effect when paired with MAS5 or PLIER preprocessing methods, even when the testing was done on the log2 scale. A simulation study was done to further examine the effect of filtering by variance. We find that filtering by variance leads to higher power, often with a decrease in false discovery rate, when paired with either of the false discovery rate methods considered. This holds regardless of the proportion of genes which are differentially expressed or whether we assume dependence or independence among genes. Conclusion The case studies show that both detection call and variance filtering are viable methods of filtering which can increase the number of differentially expressed genes identified. The

  2. Thermohydraulic analysis for power increase of IEAR-1 reactor

    International Nuclear Information System (INIS)

    Umbehaun, Pedro E.; Bastos, Jose L.F.

    1996-01-01

    In this work has been presented the reactor core thermohydraulic model of IEAR-1, aiming its power operation increase from 2MW to 5MW. The design criteria adopted have been established in Safety Series 35. Three configurations of reactor core were analysed: fuel elements 20, 25 and 30

  3. Analysis of power and frequency control requirements in view of increased decentralized production and market liberalization

    NARCIS (Netherlands)

    Roffel, B; de Boer, WW

    This paper presents a systematic approach of the analysis of the minimum control requirements that are imposed on power producing units in the Netherlands, especially in the case when decentralized production increases. Also some effects of the liberalization on the control behavior are analyzed.

  4. Well-Being Analysis of Power Systems Considering Increasing Deployment of Gas Turbines

    Directory of Open Access Journals (Sweden)

    Bomiao Liang

    2017-07-01

    Full Text Available With the significant decrease in natural gas prices in many parts of the world, the employment of gas turbine (GT units has increased steadily in recent years. The ever-increasing deployment of GT units is strengthening the interconnections between electric power and natural gas systems, which could provide a higher level of operational flexibility and reliability. As a result, the planning and operation issues in the interconnected electric power and natural gas systems have aroused concern. In these circumstances, the impacts of increasing deployment of GT units in power system operation are studied and evaluated through well-being analysis (WBA. The fast responsive characteristics of GT units are analyzed first, and the definition and adaption of WBA in a power system with increasing deployment of GT units are addressed. Then the equivalent reserve capacity of GT units is estimated, taking demand fluctuations, commitment plans, and operational risks of GT units into account. The WBA of a power system with increasing deployment of GT units is conducted considering the uncertainties of system operation states and renewable energy sources. Finally, the proposed methods are validated through an integrated version of the IEEE 118-bus power system and a 10-bus natural gas system, and the impacts of GT units on power system security under various penetration levels are examined. Simulation results demonstrate that the role of a GT unit as a low-cost electricity producer may conflict with its role as a reserve provider, but through maintaining a proper proportion of idle GT capacities for reserve, the well-being performance of the power system concerned can be significantly improved.

  5. Analysis of power and frequency control requirements in view of increased decentralized production and market liberalization

    International Nuclear Information System (INIS)

    Roffel, B.; Boer, W.W. de

    2003-01-01

    This paper presents a systematic approach of the analysis of the minimum control requirements that are imposed on power producing units in the Netherlands, especially in the case when decentralized production increases. Also some effects of the liberalization on the control behavior are analyzed. First an overview is given of the amount and type of power production in the Netherlands, followed by a review of the control requirements. Next models are described, including a simplified model for the UCTE power system. The model was tested against frequency and power measurements after failure of a 558 MW production unit in the Netherlands. Agreement between measurements and model predictions proved to be good. The model was subsequently used to analyze the primary and secondary control requirements and the impact of an increase in decentralized power production on the fault restoration capabilities of the power system. Since the latter production units are not actively participating in primary and secondary control, fault restoration takes longer and becomes unacceptable when only 35% of the power producing units participate in secondary control. Finally, the model was used to study the impact of deregulation, especially the effect of 'block scheduling', on additional control actions of the secondary control. (Author)

  6. Combining Evidence of Natural Selection with Association Analysis Increases Power to Detect Malaria-Resistance Variants

    OpenAIRE

    Ayodo, George ; Price, Alkes L. ; Keinan, Alon ; Ajwang, Arthur ; Otieno, Michael F. ; Orago, Alloys S. S. ; Patterson, Nick ; Reich, David 

    2007-01-01

    Statistical power to detect disease variants can be increased by weighting candidates by their evidence of natural selection. To demonstrate that this theoretical idea works in practice, we performed an association study of 10 putative resistance variants in 471 severe malaria cases and 474 controls from the Luo in Kenya. We replicated associations at HBB (P=.0008) and CD36 (P=.03) but also showed that the same variants are unusually differentiated in frequency between the Luo and Yoruba (who...

  7. UV-visible microscope spectrophotometric polarization and dichroism with increased discrimination power in forensic analysis

    Science.gov (United States)

    Purcell, Dale Kevin

    merit investigated included: 1) wavelength accuracy, 2) wavelength precision, 3) wavelength resolution stability, 4) photometric accuracy, 5) photometric precision, 6) photometric linearity, 7) photometric noise, and 8) short-term baseline stability. In addition, intrinsic instrument polarization effects were investigated to determine the impact of these properties on spectral interpretation and data quality. Finally, a set of recommendations were developed which describe instrument performance characteristics for microscope and spectrometer features and functions, and specific instrument parameters that must be controlled in order to acquire high quality data from an ultraviolet-visible forensic microscope spectrophotometer system for increased discrimination power.

  8. Social Power Increases Interoceptive Accuracy

    Directory of Open Access Journals (Sweden)

    Mehrad Moeini-Jazani

    2017-08-01

    Full Text Available Building on recent psychological research showing that power increases self-focused attention, we propose that having power increases accuracy in perception of bodily signals, a phenomenon known as interoceptive accuracy. Consistent with our proposition, participants in a high-power experimental condition outperformed those in the control and low-power conditions in the Schandry heartbeat-detection task. We demonstrate that the effect of power on interoceptive accuracy is not explained by participants’ physiological arousal, affective state, or general intention for accuracy. Rather, consistent with our reasoning that experiencing power shifts attentional resources inward, we show that the effect of power on interoceptive accuracy is dependent on individuals’ chronic tendency to focus on their internal sensations. Moreover, we demonstrate that individuals’ chronic sense of power also predicts interoceptive accuracy similar to, and independent of, how their situationally induced feeling of power does. We therefore provide further support on the relation between power and enhanced perception of bodily signals. Our findings offer a novel perspective–a psychophysiological account–on how power might affect judgments and behavior. We highlight and discuss some of these intriguing possibilities for future research.

  9. Analysis of liquid relief valves opening demand during pressure increase abnormal scenarios at Embalse nuclear power plant

    International Nuclear Information System (INIS)

    Bedrossian, Gustavo C.; Gersberg, Sara

    2000-01-01

    Two hypothetical scenarios have been analyzed where, after an initiating event, Embalse nuclear power plant primary heat transport system could undergo a pressure increase. These abnormal events are a loss of feedwater to the steam generators and a loss of Class IV power supply with Class III restoration. This analysis focuses on primary system liquid relief valves action, specially on their opening demand. Calculation results show that even when these valves are expected to open during the transient, primary system maximum allowable pressure would not be exceeded if they failed to open. System response was also studied in case that one of these relief valves did not close once primary system pressure decreases. For the scenario of loss of feedwater to steam generators, if the degasser-condenser could not be bottled-up, Emergency Cooling Injection conditions would be reached due to a continuos loss of coolant. In case of loss of Class IV -and assuming degasser-condenser bottling-up as service water would not be available- it was observed that primary system should remain pressurized, and with core cooled by thermo siphoning mechanism. (author)

  10. Import of electric power increased by 19 %

    International Nuclear Information System (INIS)

    Anon.

    2000-01-01

    The import of electric power increased by 19% in 1999. Due to the decrease in the electric power export the net import of electric power increased even more. Electric power import from Sweden was 6000 GWh, import from Russia 5200 GWh and import from Norway 100 GWh. The electric power export in 1999 was only 200 GWh. The generation of nuclear power increased 5% and the consumption of wood-based fuels by 3%. The increase in nuclear power generation is based on increment of the power output capacities of the power plants. The consumption of peat decreased by 12% and the production of hydroelectric power by 15%. The decrement of the peat consumption is based on the changes in energy taxation. The production of hydroelectric power decreased to the normal level after the rainy year 1998. Oil consumption remained nearly the same as in 1998 even though the national product increased in 1999 by 3.5%. The wind power generation was doubled in 1999. The share of it is still only about 0.01% of the total energy consumption. Carbon dioxide emissions from coal and peat, decreased by 1.0 million tons, down to 56 million tons. The present emissions are now only about 2 million tons higher than during the reference year 1990. The emissions have decreased by 5 million tons since 1996 when they were at their highest

  11. Alternative analysis to increase the power in combined-cycle power plants; Analisis de alternativas para el incremento de potencia en plantas termoelectricas de Ciclo Combinado

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco Cruz, Hector; Arriola Medellin, Alejandro M. [Gerencia de Procesos Termicos, Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: hpacheco@iie.org.mx; aarriola@iie.org.mx

    2010-11-15

    The electricity industry traditionally had two thermodynamic cycles for power generation: conventional steam turbine (Rankine cycle) used to supply a base load during the day, and gas turbines (Brayton cycle), for its speed response, normally used to cover peak loads. However, to provide variable peak loads, the gas turbine, as a volumetric machine is affected by the change in air density by changing the combustion temperature. This paper shows the scheme of integration of both systems, that it's known as combined cycle and the different options that would have these power plants, to maintain or increase their power in variable ambient conditions. It analyzes different options, such as: 1. Supplementary fire in the stove. 2. Air cooling intake in the gas turbine (evaporation system or mechanical system). 3. Steam injection in the combustion chamber. [Spanish] La industria electrica tradicionalmente a contado con dos ciclos termodinamicos para generacion electrica: las turbinas convencionales de vapor (ciclo de Rankine) se utilizan para suministrar una carga base durante el dia, y las turbinas de gas (ciclo de Brayton), por su rapidez de respuesta, se utilizan normalmente para cubrir las cargas pico. Sin embargo, para suministrar las cargas variables pico, la turbina a gas, por ser una maquina volumetrica, se ve afectada por el cambio de la densidad del aire de combustion al cambiar la temperatura ambiente. En este trabajo se muestra el esquema de integracion de ambos sistemas, en lo que se conoce como ciclo combinado y las diferentes opciones que tendrian estas plantas de generacion electrica para mantener o incrementar su potencia en condiciones ambiente variable. Para ello se analizan diferentes opciones, tales como: 1.- Combustion suplementaria en el recuperador de calor. 2.- Enfriamiento del aire de admision a la turbina de gas (mediante un sistema de evaporacion o mediante un sistema mecanico). 3.- Inyeccion de vapor a la camara de combustion. Palabras

  12. Licensing process for the power increase

    International Nuclear Information System (INIS)

    Perez P, R.; Mamani A, Y.R.; Salgado G, J.R.

    2006-01-01

    The licensing process for the power increase of a nuclear power station is presented, this includes the description of the effective normative framework, the attributions of the one Mexican regulator organism in nuclear matter, the definition and importance of the power level of a nuclear reactor for the safety studies. Also, the types of power increase according to its magnitude, and the regulator process that it includes the scope and the detail of the required information that it should be evaluated by the one regulator organism are discussed. Finally it offers a summary of the experience that one has in Mexico for this type of processes. (Author)

  13. Increase of hydroelectric power plant operation reliability

    International Nuclear Information System (INIS)

    Koshumbaev, M.B.

    2006-01-01

    The new design of the turbine of hydroelectric power plant (HPP) is executed in the form of a pipe with plates. Proposed solution allows increasing the hydroelectric power plant capacity at existing head and water flow. At that time the HPP turbine reliability is increase, its operation performances are improving. Design efficiency is effective mostly for small-scale and micro-HPP due to reliable operation, low-end technology, and harmless ecological application. (author)

  14. Power increases infidelity among men and women.

    Science.gov (United States)

    Lammers, Joris; Stoker, Janka I; Jordan, Jennifer; Pollmann, Monique; Stapel, Diederik A

    2011-09-01

    Data from a large survey of 1,561 professionals were used to examine the relationship between power and infidelity and the process underlying this relationship. Results showed that elevated power is positively associated with infidelity because power increases confidence in the ability to attract partners. This association was found for both actual infidelity and intentions to engage in infidelity in the future. Gender did not moderate these results: The relationship between power and infidelity was the same for women as for men, and for the same reason. These findings suggest that the common assumption (and often-found effect) that women are less likely than men to engage in infidelity is, at least partially, a reflection of traditional gender-based differences in power that exist in society.

  15. Nuclear power regional analysis

    International Nuclear Information System (INIS)

    Parera, María Delia

    2011-01-01

    In this study, a regional analysis of the Argentine electricity market was carried out considering the effects of regional cooperation, national and international interconnections; additionally, the possibilities of insertion of new nuclear power plants in different regions were evaluated, indicating the most suitable areas for these facilities to increase the penetration of nuclear energy in national energy matrix. The interconnection of electricity markets and natural gas due to the linkage between both energy forms was also studied. With this purpose, MESSAGE program was used (Model for Energy Supply Strategy Alternatives and their General Environmental Impacts), promoted by the International Atomic Energy Agency (IAEA). This model performs a country-level economic optimization, resulting in the minimum cost for the modelling system. Regionalization executed by the Wholesale Electricity Market Management Company (CAMMESA, by its Spanish acronym) that divides the country into eight regions. The characteristics and the needs of each region, their respective demands and supplies of electricity and natural gas, as well as existing and planned interconnections, consisting of power lines and pipelines were taken into account. According to the results obtained through the model, nuclear is a competitive option. (author) [es

  16. Nuclear power ecology: comparative analysis

    International Nuclear Information System (INIS)

    Trofimenko, A.P.; Lips'ka, A.Yi.; Pisanko, Zh.Yi.

    2005-01-01

    Ecological effects of different energy sources are compared. Main actions for further nuclear power development - safety increase and waste management, are noted. Reasons of restrained public position to nuclear power and role of social and political factors in it are analyzed. An attempt is undertaken to separate real difficulties of nuclear power from imaginary ones that appear in some mass media. International actions of environment protection are noted. Risk factors at different energy source using are compared. The results of analysis indicate that ecological influence and risk for nuclear power are of minimum

  17. System-wide emissions implications of increased wind power penetration.

    Science.gov (United States)

    Valentino, Lauren; Valenzuela, Viviana; Botterud, Audun; Zhou, Zhi; Conzelmann, Guenter

    2012-04-03

    This paper discusses the environmental effects of incorporating wind energy into the electric power system. We present a detailed emissions analysis based on comprehensive modeling of power system operations with unit commitment and economic dispatch for different wind penetration levels. First, by minimizing cost, the unit commitment model decides which thermal power plants will be utilized based on a wind power forecast, and then, the economic dispatch model dictates the level of production for each unit as a function of the realized wind power generation. Finally, knowing the power production from each power plant, the emissions are calculated. The emissions model incorporates the effects of both cycling and start-ups of thermal power plants in analyzing emissions from an electric power system with increasing levels of wind power. Our results for the power system in the state of Illinois show significant emissions effects from increased cycling and particularly start-ups of thermal power plants. However, we conclude that as the wind power penetration increases, pollutant emissions decrease overall due to the replacement of fossil fuels.

  18. Something old and something new: wedding recombinant inbred lines with traditional line cross analysis increases power to describe gene interactions.

    Science.gov (United States)

    Elnaccash, Tarek W; Tonsor, Stephen J

    2010-04-16

    In this paper we present a novel approach to quantifying genetic architecture that combines recombinant inbred lines (RIL) with line cross analysis (LCA). LCA is a method of quantifying directional genetic effects (i.e. summed effects of all loci) that differentiate two parental lines. Directional genetic effects are thought to be critical components of genetic architecture for the long term response to selection and as a cause of inbreeding depression. LCA typically begins with two inbred parental lines that are crossed to produce several generations such as F1, F2, and backcrosses to each parent. When a RIL population (founded from the same P1 and P2 as was used to found the line cross population) is added to the LCA, the sampling variance of several nonadditive genetic effect estimates is greatly reduced. Specifically, estimates of directional dominance, additive x additive, and dominance x dominance epistatic effects are reduced by 92%, 94%, and 56% respectively. The RIL population can be simultaneously used for QTL identification, thus uncovering the effects of specific loci or genomic regions as elements of genetic architecture. LCA and QTL mapping with RIL provide two qualitatively different measures of genetic architecture with the potential to overcome weaknesses of each approach alone. This approach provides cross-validation of the estimates of additive and additive x additive effects, much smaller confidence intervals on dominance, additive x additive and dominance x dominance estimates, qualitatively different measures of genetic architecture, and the potential when used together to balance the weaknesses of LCA or RIL QTL analyses when used alone.

  19. Delayed power analysis

    International Nuclear Information System (INIS)

    Adamovich, L.A.; Azarov, V.V.

    1999-01-01

    Time dependent core power behavior in a nuclear reactor is described with well-known neutron kinetics equations. At the same time, two portions are distinguished in energy released from uranium nuclei fission; one released directly at fission and another delayed (residual) portion produced during radioactive decay of fission products. While prompt power is definitely described with kinetics equations, the delayed power presentation still remains outstanding. Since in operation the delayed power part is relatively small (about 6%) operation, it can be neglected for small reactivity disturbances assuming that entire power obeys neutron kinetics equations. In case of a high negative reactivity rapidly inserted in core (e.g. reactor scram initiation) the prompt and delayed components can be calculated separately with practically no impact on each other, employing kinetics equations for prompt power and known approximation formulas for delayed portion, named residual in this specific case. Under substantial disturbances the prompt component in the dynamic process becomes commensurable with delayed portion, thus making necessary to take into account their cross impact. A system of differential equations to describe time-dependent behavior of delayed power is presented. Specific NPP analysis shows a way to significantly simplify the task formulation. (author)

  20. Combined analysis of data from two granddaughter designs: A simple strategy for QTL confirmation and increasing experimental power in dairy cattle

    Directory of Open Access Journals (Sweden)

    Blümel Jürgen

    2003-05-01

    Full Text Available Abstract A joint analysis of five paternal half-sib Holstein families that were part of two different granddaughter designs (ADR- or Inra-design was carried out for five milk production traits and somatic cell score in order to conduct a QTL confirmation study and to increase the experimental power. Data were exchanged in a coded and standardised form. The combined data set (JOINT-design consisted of on average 231 sires per grandsire. Genetic maps were calculated for 133 markers distributed over nine chromosomes. QTL analyses were performed separately for each design and each trait. The results revealed QTL for milk production on chromosome 14, for milk yield on chromosome 5, and for fat content on chromosome 19 in both the ADR- and the Inra-design (confirmed within this study. Some QTL could only be mapped in either the ADR- or in the Inra-design (not confirmed within this study. Additional QTL previously undetected in the single designs were mapped in the JOINT-design for fat yield (chromosome 19 and 26, protein yield (chromosome 26, protein content (chromosome 5, and somatic cell score (chromosome 2 and 19 with genomewide significance. This study demonstrated the potential benefits of a combined analysis of data from different granddaughter designs.

  1. Increasing the efficiency of thermal power stations

    International Nuclear Information System (INIS)

    Schwarz, N.F.

    1984-01-01

    High energy prices and an increased investment of costs in power plants as well as the necessity to minimize all kinds of environmental pollution have severe consequences on the construction and operation of thermal power stations. One of the most promising measures to cope with the mentioned problems is to raise the thermal efficiency of power plants. With the example of an Austrian electric utility it can be shown that by application of high efficiency combined cycles primary energy can be converted into electricity in a most efficient manner. Excellent operating experience has proved the high reliability of these relatively complex systems. Raising the temperature of the gas topping process still higher will not raise the efficiency considerably. In this respect a Rankine cycle is superior to a Brayton cycle. In a temperature range of 850 to 900 0 C were conventional materials with known properties can still be used, only the alkali metals cesium and potassium have the necessary physical and thermodynamic properties for application in Rankine topping cycles. Building on experience gained in the Fast Breeder development and from the US space program, a potassium topping cycle linked to a conventional water steam cycle with an intermediate diphenyl vapour cycle has been proposed which should give thermal efficiencies in excess of 50%. In a multi-national program this so called Treble Rankine Cycle is being investigated under the auspices of the International Energy Agency. Work is in progress to investigate the technical and economic feasibility of this energy conversion system. Experimental investigations are already under way in the Austrian Research Center Seibersdorf where high temperature liquid metal test facilities have been operated since 1968. (Author)

  2. Residual services and power increases for components

    International Nuclear Information System (INIS)

    Pauli, W.

    1991-01-01

    As part of the moratorium in Switzerland work in nuclear power stations has been concentrating more on increasing capacity, reducing radiation levels to which personnel is exposed and extending the service life of existing plants. This has meant the requalification, repair or replacement of components and systems some of which have been in operation for more than 20 years. In addition to the classic role of manufacturer, the industry which acts as both supplier and manufacturer of these components also has to be the expertise holder, documentation pool and analysts. The examples described in this article show that close cooperation with operators leads to solutions which fully ensure the safe and successful operation of the plants, even in the second section of their service life. 4 refs

  3. Soil Parameter Mapping and Ad Hoc Power Analysis to Increase Blocking Efficiency Prior to Establishing a Long-Term Field Experiment.

    Science.gov (United States)

    Collins, Doug; Benedict, Chris; Bary, Andy; Cogger, Craig

    2015-01-01

    The spatial heterogeneity of soil and weed populations poses a challenge to researchers. Unlike aboveground variability, below-ground variability is more difficult to discern without a strategic soil sampling pattern. While blocking is commonly used to control environmental variation, this strategy is rarely informed by data about current soil conditions. Fifty georeferenced sites were located in a 0.65 ha area prior to establishing a long-term field experiment. Soil organic matter (OM) and weed seed bank populations were analyzed at each site and the spatial structure was modeled with semivariograms and interpolated with kriging to map the surface. These maps were used to formulate three strategic blocking patterns and the efficiency of each pattern was compared to a completely randomized design and a west to east model not informed by soil variability. Compared to OM, weeds were more variable across the landscape and had a shorter range of autocorrelation, and models to increase blocking efficiency resulted in less increase in power. Weeds and OM were not correlated, so no model examined improved power equally for both parameters. Compared to the west to east blocking pattern, the final blocking pattern chosen resulted in a 7-fold increase in power for OM and a 36% increase in power for weeds.

  4. Soil Parameter Mapping and Ad Hoc Power Analysis to Increase Blocking Efficiency Prior to Establishing a Long-Term Field Experiment

    Science.gov (United States)

    Collins, Doug; Benedict, Chris; Bary, Andy; Cogger, Craig

    2015-01-01

    The spatial heterogeneity of soil and weed populations poses a challenge to researchers. Unlike aboveground variability, below-ground variability is more difficult to discern without a strategic soil sampling pattern. While blocking is commonly used to control environmental variation, this strategy is rarely informed by data about current soil conditions. Fifty georeferenced sites were located in a 0.65 ha area prior to establishing a long-term field experiment. Soil organic matter (OM) and weed seed bank populations were analyzed at each site and the spatial structure was modeled with semivariograms and interpolated with kriging to map the surface. These maps were used to formulate three strategic blocking patterns and the efficiency of each pattern was compared to a completely randomized design and a west to east model not informed by soil variability. Compared to OM, weeds were more variable across the landscape and had a shorter range of autocorrelation, and models to increase blocking efficiency resulted in less increase in power. Weeds and OM were not correlated, so no model examined improved power equally for both parameters. Compared to the west to east blocking pattern, the final blocking pattern chosen resulted in a 7-fold increase in power for OM and a 36% increase in power for weeds. PMID:26247056

  5. Soil Parameter Mapping and Ad Hoc Power Analysis to Increase Blocking Efficiency Prior to Establishing a Long-Term Field Experiment

    Directory of Open Access Journals (Sweden)

    Doug Collins

    2015-01-01

    Full Text Available The spatial heterogeneity of soil and weed populations poses a challenge to researchers. Unlike aboveground variability, below-ground variability is more difficult to discern without a strategic soil sampling pattern. While blocking is commonly used to control environmental variation, this strategy is rarely informed by data about current soil conditions. Fifty georeferenced sites were located in a 0.65 ha area prior to establishing a long-term field experiment. Soil organic matter (OM and weed seed bank populations were analyzed at each site and the spatial structure was modeled with semivariograms and interpolated with kriging to map the surface. These maps were used to formulate three strategic blocking patterns and the efficiency of each pattern was compared to a completely randomized design and a west to east model not informed by soil variability. Compared to OM, weeds were more variable across the landscape and had a shorter range of autocorrelation, and models to increase blocking efficiency resulted in less increase in power. Weeds and OM were not correlated, so no model examined improved power equally for both parameters. Compared to the west to east blocking pattern, the final blocking pattern chosen resulted in a 7-fold increase in power for OM and a 36% increase in power for weeds.

  6. The Increase of Power Efficiency of Underground Coal Mining by the Forecasting of Electric Power Consumption

    Science.gov (United States)

    Efremenko, Vladimir; Belyaevsky, Roman; Skrebneva, Evgeniya

    2017-11-01

    In article the analysis of electric power consumption and problems of power saving on coal mines are considered. Nowadays the share of conditionally constant costs of electric power for providing safe working conditions underground on coal mines is big. Therefore, the power efficiency of underground coal mining depends on electric power expense of the main technological processes and size of conditionally constant costs. The important direction of increase of power efficiency of coal mining is forecasting of a power consumption and monitoring of electric power expense. One of the main approaches to reducing of electric power costs is increase in accuracy of the enterprise demand in the wholesale electric power market. It is offered to use artificial neural networks to forecasting of day-ahead power consumption with hourly breakdown. At the same time use of neural and indistinct (hybrid) systems on the principles of fuzzy logic, neural networks and genetic algorithms is more preferable. This model allows to do exact short-term forecasts at a small array of input data. A set of the input parameters characterizing mining-and-geological and technological features of the enterprise is offered.

  7. Increased nuclear safety and reliability through power beaming

    International Nuclear Information System (INIS)

    Coomes, E.P.; Widrig, R.D.

    1989-01-01

    Space satellites and platforms currently include self-contained power systems to supply the energy necessary to accomplish mission objectives. With power beaming, the power system is separate from the satellite and the two are connected by an energy beam. This approach is analogous to earth-based central station power generation and distribution over transmission lines to various customers. In space, power is produced by power satellites (central power generating stations) and transmitted via energy beams to individual users. Power beaming has the ability to provide an order of magnitude increase in power availability over solar-based power systems with less mass on orbit. The technologies needed for power beaming are being developed today under existing programs directed by the Strategic Defense Initiative Office, the National Aeronautics and Space Administration, and the US Department of Energy. A space power architecture based on power beaming would greatly increase the safety and reliability of employing nuclear power in space

  8. Valka to increase biofuel power capacity

    Index Scriptorium Estoniae

    2011-01-01

    Eesti Energia omandas enamusosaluse Valka soojusettevõttes Host Energo. Eesti Energiale kuulub nüüd 90% ettevõttest ja linnale 10%. Ettevõte uus nimi on Enefit Heat&Power Valka ja viimane rajab aastaks 2012 Valka uue biokütusel koostootmisjaama

  9. Investigating power control in autonomous power systems with increasing wind power penetration

    Energy Technology Data Exchange (ETDEWEB)

    Margaris, Ioannis D. [National Technical Univ. of Athens (Greece). Electric Energy Systems Lab.; Hansen, Anca D.; Sorensen, Poul [Risoe National Laboratory, Roskilde (Denmark). Wind Energy Dept.; Hatziargyriou, Nikos D. [National Technical Univ. of Athens (Greece). Electric Energy Systems Lab.; Public Power Corporation S.A., Athens (Greece)

    2009-07-01

    Increasing levels of wind penetration in autonomous power systems has set intensively high standards with respect to wind turbine technology during the last years. Special features of non-interconnected power systems make security issues rather critical, as the operation of large wind farms like conventional power plants is becoming a necessity. This paper includes the study case of Rhodos island, in Greece, where rapidly increasing wind penetration has started to impose serious security issues for the immediate future. The scenarios studied here correspond to reference year of study 2012 and include wind farms with three different wind turbine technologies - namely Doubly Fed Induction Generator (DFIG), Permanent Magnet Synchronous Generator (PMSG) and Active Stall Induction Generator (ASIG) based wind turbines. Aggregated models of the wind farms are being used and results for different load cases are being analyzed and discussed. The ability of wind farms to assist in some of the power system control services traditionally carried out by conventional synchronous generation is being investigated and discussed. The power grid of the island, including speed governors and automatic voltage regulators, is simulated in the dedicated power system simulation program Power Factory from DIgSILENT. (orig.)

  10. Does accounting for seizure frequency variability increase clinical trial power?

    Science.gov (United States)

    Goldenholz, Daniel M; Goldenholz, Shira R; Moss, Robert; French, Jacqueline; Lowenstein, Daniel; Kuzniecky, Ruben; Haut, Sheryl; Cristofaro, Sabrina; Detyniecki, Kamil; Hixson, John; Karoly, Philippa; Cook, Mark; Strashny, Alex; Theodore, William H; Pieper, Carl

    2017-11-01

    Seizure frequency variability is associated with placebo responses in randomized controlled trials (RCT). Increased variability can result in drug misclassification and, hence, decreased statistical power. We investigated a new method that directly incorporated variability into RCT analysis, Z V . Two models were assessed: the traditional 50%-responder rate (RR50), and the variability-corrected score, Z V . Each predicted seizure frequency upper and lower limits using prior seizures. Accuracy was defined as percentage of time-intervals when the observed seizure frequencies were within the predicted limits. First, we tested the Z V method on three datasets (SeizureTracker: n=3016, Human Epilepsy Project: n=107, and NeuroVista: n=15). An additional independent SeizureTracker validation dataset was used to generate a set of 200 simulated trials each for 5 different sample sizes (total N=100 to 500 by 100), assuming 20% dropout and 30% drug efficacy. "Power" was determined as the percentage of trials successfully distinguishing placebo from drug (p90% power at N=100 per arm while RR50 required N=200 per arm. Z V may increase the statistical power of an RCT relative to the traditional RR50. Published by Elsevier B.V.

  11. Clock Tree Power Analysis

    OpenAIRE

    Austbø, Knut

    2016-01-01

    The buffered clock tree structure is commonly used to distribute the clock signal to the memory elements in digital circuits. Since the clock signal is used as a temporal reference, it has to be distributed to the registers with decent timing characteristics and low skew. In order to achieve this, buffers and inverters are inserted in the clock tree, typically by a synthesis tool. The clock tree is a major contributor to the power consumption. This is a result of a combination of high swit...

  12. Prospects of increasing the power of a two-circuit geothermal power plant

    International Nuclear Information System (INIS)

    Alkhasov, A.B.

    2001-01-01

    The results of analysis of the thermodynamical cycle of the geothermal NPPs secondary circuit with various versions of the geothermal circulation system are presented. It is shown, that the technological scheme with horizontal well is the optimal one. The conclusion is made that by further assimilation of thermal power with application of the experience, accumulated by petroleum specialist, it is necessary to built up geothermal circulation systems with horizontal wells. This will sharply increase the indices of the geothermal branch, its efficiency and competivity as compared to the traditional power engineering [ru

  13. Power increases hypocrisy: moralizing in reasoning, immorality in behavior.

    Science.gov (United States)

    Lammers, Joris; Stapel, Diederik A; Galinsky, Adam D

    2010-05-01

    In five studies, we explored whether power increases moral hypocrisy (i.e., imposing strict moral standards on other people but practicing less strict moral behavior oneself). In Experiment 1, compared with the powerless, the powerful condemned other people's cheating more, but also cheated more themselves. In Experiments 2 through 4, the powerful were more strict in judging other people's moral transgressions than in judging their own transgressions. A final study found that the effect of power on moral hypocrisy depends on the legitimacy of the power: When power was illegitimate, the moral-hypocrisy effect was reversed, with the illegitimately powerful becoming stricter in judging their own behavior than in judging other people's behavior. This pattern, which might be dubbed hypercrisy, was also found among low-power participants in Experiments 3 and 4. We discuss how patterns of hypocrisy and hypercrisy among the powerful and powerless can help perpetuate social inequality.

  14. Improving BWR fuel critical power without increasing bundle pressure drop

    International Nuclear Information System (INIS)

    Matzner, B.; Shiraishi, L.M.; Danielson, D.W.; Congdon, S.P.

    2004-01-01

    It has been almost axiomatic that BWR fuel bundle critical power performance could not be improved without an accompanying increase in bundle pressure drop. It appeared that in order to increase the bundle dryout resistance it was necessary to perturb the bundle coolant flow paths in some fashion. This resulted in an unacceptable bundle pressure drop increase. However, by adding part length rods to decrease bundle pressure drop and by inserting an extra spacer with rearranged spacer pitch and flow trippers on the channel wall at the top of the bundle to increase critical power it was possible to achieve the goal of increased bundle critical power without pressure drop increase. (author)

  15. Auxetic piezoelectric energy harvesters for increased electric power output

    Directory of Open Access Journals (Sweden)

    Qiang Li

    2017-01-01

    Full Text Available This letter presents a piezoelectric bimorph with auxetic (negative Poisson’s ratio behaviors for increased power output in vibration energy harvesting. The piezoelectric bimorph comprises a 2D auxetic substrate sandwiched between two piezoelectric layers. The auxetic substrate is capable of introducing auxetic behaviors and thus increasing the transverse stress in the piezoelectric layers when the bimorph is subjected to a longitudinal stretching load. As a result, both 31- and 32-modes are simultaneously exploited to generate electric power, leading to an increased power output. The increasing power output principle was theoretically analyzed and verified by finite element (FE modelling. The FE modelling results showed that the auxetic substrate can increase the transverse stress of a bimorph by 16.7 times. The average power generated by the auxetic bimorph is 2.76 times of that generated by a conventional bimorph.

  16. Thermal Power Plant Performance Analysis

    CERN Document Server

    2012-01-01

    The analysis of the reliability and availability of power plants is frequently based on simple indexes that do not take into account the criticality of some failures used for availability analysis. This criticality should be evaluated based on concepts of reliability which consider the effect of a component failure on the performance of the entire plant. System reliability analysis tools provide a root-cause analysis leading to the improvement of the plant maintenance plan.   Taking in view that the power plant performance can be evaluated not only based on  thermodynamic related indexes, such as heat-rate, Thermal Power Plant Performance Analysis focuses on the presentation of reliability-based tools used to define performance of complex systems and introduces the basic concepts of reliability, maintainability and risk analysis aiming at their application as tools for power plant performance improvement, including: ·         selection of critical equipment and components, ·         defini...

  17. Power Computations for Intervention Analysis

    Science.gov (United States)

    McLeod, A. I.; Vingilis, E. R.

    2009-01-01

    In many intervention analysis applications, time series data may be expensive or otherwise difficult to collect. In this case the power function is helpful, because it can be used to determine the probability that a proposed intervention analysis application will detect a meaningful change. Assuming that an underlying autoregressive integrated moving average (ARIMA) or fractional ARIMA model is known or can be estimated from the preintervention time series, the methodology for computing the required power function is developed for pulse, step, and ramp interventions with ARIMA and fractional ARIMA errors. Convenient formulas for computing the power function for important special cases are given. Illustrative applications in traffic safety and environmental impact assessment are discussed. PMID:19629193

  18. Ejectors of power plants turbine units efficiency and reliability increasing

    Science.gov (United States)

    Aronson, K. E.; Ryabchikov, A. Yu.; Kuptsov, V. K.; Murmanskii, I. B.; Brodov, Yu. M.; Zhelonkin, N. V.; Khaet, S. I.

    2017-11-01

    The functioning of steam turbines condensation systems influence on the efficiency and reliability of a power plant a lot. At the same time, the condensation system operating is provided by basic ejectors, which maintain the vacuum level in the condenser. Development of methods of efficiency and reliability increasing for ejector functioning is an actual problem of up-to-date power engineering. In the paper there is presented statistical analysis of ejector breakdowns, revealed during repairing processes, the influence of such damages on the steam turbine operating reliability. It is determined, that 3% of steam turbine equipment breakdowns are the ejector breakdowns. At the same time, about 7% of turbine breakdowns are caused by different ejector malfunctions. Developed and approved design solutions, which can increase the ejector functioning indexes, are presented. Intercoolers are designed in separated cases, so the air-steam mixture can’t move from the high-pressure zones to the low-pressure zones and the maintainability of the apparatuses is increased. By U-type tubes application, the thermal expansion effect of intercooler tubes is compensated and the heat-transfer area is increased. By the applied nozzle fixing construction, it is possible to change the distance between a nozzle and a mixing chamber (nozzle exit position) for operating performance optimization. In operating conditions there are provided experimental researches of more than 30 serial ejectors and also high-efficient 3-staged ejector EPO-3-80, designed by authors. The measurement scheme of the designed ejector includes 21 indicator. The results of experimental tests with different nozzle exit positions of the ejector EPO-3-80 stream devices are presented. The pressure of primary stream (water steam) is optimized. Experimental data are well-approved by the calculation results.

  19. Increase in the import of the electric power

    International Nuclear Information System (INIS)

    Kangas, H.

    2000-01-01

    Exceptionally large amounts of electric power were imported in Finland from Sweden during the spring and early summer. The reason for this was the good conditions for production of hydroelectric power. Because of the imports it has been possible to reduce the generation of the expensive domestic condensing power. The consumption of electric power increased, compared to May 1998, by 1.7%. The private consumption of electric power was 7-8% due to the lower average temperature of the year 1999. May 1999 has been about two deg C lower than the long-term average. About 6.1 TWh of power was consumed in Finland in May 1999, while the consumption in May 1998 was about 100 GWh lower. The power consumption of the past 12 months was 76.9 TWh, which is about 2.1% higher than the value of the previous 12 months. The long lasting increase in production of hydroelectric power started to cease. The hydroelectric power generated in May-June 1999 exceeded 1.2 TWh, the reduction, compared to the previous year, was only a little over 5%. The production of hydroelectric power during the past 12 months was 15.4 TWh. This corresponds to 20% of the total power demand in Finland. The corresponding value of the previous year was nearly 22%. The generation of wind power in May-June 1999 was about 5 GWh, the amount of the previous 12 months being 29 GWh. Both of these values are about twice higher than the figures of the 12 months before that. The power generation capacity of Finnish nuclear power plants in May-June 1999 less than 3.4 TWh, which are about 15% higher than the value of the previous year. The share of nuclear power during May-June 1999 of the total amount of power consumption was 30%. The amount of nuclear power generated during the first half of the year in Finland was more than 11 TWh. The nuclear power generation capacity of the previous 12 months was 21.8 TWh. Cogeneration of power and heat has been nearly the same both in 1998 and 1999, the growth being only 1.4%. The

  20. Green certificates will lead to increased electric power production

    International Nuclear Information System (INIS)

    Lind, Oddvar

    2004-01-01

    The implementation of green certificates will lead to increased electricity production from renewable energy sources and less risk of price crises. For the time being, a common market for green certificates will be established with Sweden from January 1, 2006. It is possible to realise a ''compulsory total quota'' of 20 TWh by 2016. Green certificates will imply a premium on the electricity bill. However, the quota system will imply increased power generation, which in turn tends to lower the price. Norway should in principle follow Sweden's definition of renewable energy: all new hydroelectric power, wind power, solar energy, wave and tidal power, biomass energy, and energy recovery. The certificate regime will apply to new investments in renewable power production. However, it would be natural to include the established renewable power production that is currently receiving support. Some critics fear that the consumers rather than the authorities will subsidize the production of green power. The point is being made that central EU countries may save great sums by investing in renewable energy in Norway

  1. Techniques used to increase the resolving power of magnetic ...

    African Journals Online (AJOL)

    Magnetic resonance imaging is a method which can be used to obtain highly detailed and clear images of organs inside the body. The objective of this article is evaluation of techniques used to increase the resolving power of magnetic resonance images. The use of gradient techniques with high functionality will increase ...

  2. A new application of quasi power increasing sequences

    Science.gov (United States)

    Özarslan, Hikmet Seyhan

    2018-01-01

    In the present paper, we prove a general theorem dealing with absolute matrix summability methods of infinite series by using the concept of quasi power increasing sequence instead of almost increasing sequence. Some important known theorems are deduced from our theorem.

  3. Quantifying the increasing sensitivity of power systems to climate variability

    Science.gov (United States)

    Bloomfield, H. C.; Brayshaw, D. J.; Shaffrey, L. C.; Coker, P. J.; Thornton, H. E.

    2016-12-01

    Large quantities of weather-dependent renewable energy generation are expected in power systems under climate change mitigation policies, yet little attention has been given to the impact of long term climate variability. By combining state-of-the-art multi-decadal meteorological records with a parsimonious representation of a power system, this study characterises the impact of year-to-year climate variability on multiple aspects of the power system of Great Britain (including coal, gas and nuclear generation), demonstrating why multi-decadal approaches are necessary. All aspects of the example system are impacted by inter-annual climate variability, with the impacts being most pronounced for baseload generation. The impacts of inter-annual climate variability increase in a 2025 wind-power scenario, with a 4-fold increase in the inter-annual range of operating hours for baseload such as nuclear. The impacts on peak load and peaking-plant are comparably small. Less than 10 years of power supply and demand data are shown to be insufficient for providing robust power system planning guidance. This suggests renewable integration studies—widely used in policy, investment and system design—should adopt a more robust approach to climate characterisation.

  4. Power analysis of trials with multilevel data

    CERN Document Server

    Moerbeek, Mirjam

    2015-01-01

    Power Analysis of Trials with Multilevel Data covers using power and sample size calculations to design trials that involve nested data structures. The book gives a thorough overview of power analysis that details terminology and notation, outlines key concepts of statistical power and power analysis, and explains why they are necessary in trial design. It guides you in performing power calculations with hierarchical data, which enables more effective trial design.The authors are leading experts in the field who recognize that power analysis has attracted attention from applied statisticians i

  5. PowerFactory applications for power system analysis

    CERN Document Server

    Gonzalez-Longatt, Francisco

    2014-01-01

    This book presents a comprehensive set of guidelines and applications of DIgSILENT PowerFactory, an advanced power system simulation software package, for different types of power systems studies. Written by specialists in the field, it combines expertise and years of experience in the use of DIgSILENT PowerFactory with a deep understanding of power systems analysis. These complementary approaches therefore provide a fresh perspective on how to model, simulate and analyse power systems. It presents methodological approaches for modelling of system components, including both classical and non-

  6. Does green consumerism increase the acceptance of wind power?

    International Nuclear Information System (INIS)

    Thøgersen, John; Noblet, Caroline

    2012-01-01

    In this paper, we discuss what might be termed an action-based learning approach to promoting important pro-environmental actions, such as support for or acceptance of environmental policy. Such an approach involves promoting simple and easy behaviours as entry points for more radical steps towards sustainability, referred to as “catalytic” or “wedge” behaviours. Despite the obvious need for innovative approaches to promote important pro-environmental behaviour, and sound theoretical backing for such concepts, there is a lack of research testing the key propositions of this approach. In a survey study based on a random sample of residents of the state of Maine, USA, we find that both everyday “green” behaviour and the acceptance of an expansion of wind power are rooted in environmental concern and that everyday “green” behaviour gives a significant contribution to predicting acceptance of wind power when controlling for environmental concern. Hence, the promotion of everyday “green” behaviours may prepare the grounds for increasing acceptance of more far-reaching changes in the population, such as an expansion of wind power. - Highlights: ► Acceptance of wind power increases with environmental concern. ► So does everyday “green” consumerism. ► Green consumerism further increases acceptance of wind power. ► The effect of environmental concern on acceptance is partly mediated through green consumerism. ► Participants in the study are a random sample of residents of Maine, USA.

  7. Statistical Power in Meta-Analysis

    Science.gov (United States)

    Liu, Jin

    2015-01-01

    Statistical power is important in a meta-analysis study, although few studies have examined the performance of simulated power in meta-analysis. The purpose of this study is to inform researchers about statistical power estimation on two sample mean difference test under different situations: (1) the discrepancy between the analytical power and…

  8. METHODOLOGY OF MATHEMATICAL ANALYSIS IN POWER NETWORK

    OpenAIRE

    Jerzy Szkutnik; Mariusz Kawecki

    2008-01-01

    Power distribution network analysis is taken into account. Based on correlation coefficient authors establish methodology of mathematical analysis useful in finding substations bear responsibility for power stoppage. Also methodology of risk assessment will be carried out.

  9. Money in the bank : Feeling powerful increases saving

    NARCIS (Netherlands)

    Garbinsky, E.; Klesse, A.K.; Aaker, J.

    2014-01-01

    Across five studies, this research reveals that feeling powerful increases saving. This effect is driven by the desire to maintain one’s current state. When the purpose of saving is no longer to accumulate money but to spend it on a status-related product, the basic effect is reversed, and those who

  10. Hydroelectric power in Switzerland: large growth potential by increasing the installed power

    International Nuclear Information System (INIS)

    Schleiss, A.

    2007-01-01

    Due to its important hydroelectric power generation facilities (about 525 plants with a total power of 13,314 MW producing about 35.3 TWh annually) Switzerland plays an important role in the interconnected European power system. Large artificial storage lakes in the Swiss Alps can generate peak power during hours of highest demand: 9700 MW are available from accumulated energy and the total power of pumped-storage facilities amounts to 1700 MW. The latter allow refilling the reservoirs at periods of low power demand and generating power at periods of peak demand. In the case of favorable conditions, the yearly average power production could be increased by 6% and the production during the winter period (October to March) by 20% by the year 2020. However, looking forward to the year 2050, the annual production is expected to decrease by 3% despite a possible extension of hydropower. This decrease is due to the enforcement of the minimum residual water flow rates required by a new legislation to protect the rivers. The enforcement is due at latest when the present licenses for water utilization expire. On the other hand, the installed (peak) power might be further increased by 50% by retrofitting the existing installations and constructing the pumped-storage plants currently at the planning stage

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

    International Nuclear Information System (INIS)

    Martinez, Alvaro; Astrain, David; Aranguren, Patricia

    2016-01-01

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

  12. Power in Bayesian Mediation Analysis for Small Sample Research

    NARCIS (Netherlands)

    Miočević, M.; MacKinnon, David; Levy, Roy

    2017-01-01

    Bayesian methods have the potential for increasing power in mediation analysis (Koopman, Howe, Hollenbeck, & Sin, 2015; Yuan & MacKinnon, 2009). This article compares the power of Bayesian credibility intervals for the mediated effect to the power of normal theory, distribution of the product,

  13. Justification for an Increase in Authorized Operating Power at HFIR

    International Nuclear Information System (INIS)

    Primm, Trent; Ilas, Germina

    2011-01-01

    Using verified and validated reactor physics methods coupled to a currently accepted thermal hydraulic analysis methodology, onset of incipient boiling power agrees well with the currently-accepted safety basis value. The MCNP-based methodology is acceptable for scoping studies of LEU fuel conversion. A balance-of-plant assessment would have to be conducted to determine if the power up-rate to 100 MW could be supported for LEU fuel. While analyses performed 45 years ago have been shown to be in agreement with today s methods, there is an advantage to the current methodology in that people working at HFIR today can explain/justify/defend the safety analyses rather than relying solely on documentation.

  14. Increased wheeze but not bronchial hyperreactivity near power stations.

    Science.gov (United States)

    Halliday, J A; Henry, R L; Hankin, R G; Hensley, M J

    1993-08-01

    In a previous study a higher than expected prevalence of asthma was found in Lake Munmorah, a coastal town near two power stations, compared with another coastal control town. This study aimed to compare atopy, bronchial hyperreactivity, and reported symptoms of asthma in the power station town and a second control area with greater socioeconomic similarity. A cross sectional survey was undertaken. Lake Munmorah, a coastal town near two power stations, and Dungog, a country town in the Hunter Valley, NSW, Australia. All children attending kindergarten to year 6 at all schools in the two towns were invited to participate in 1990. The response rates for the questionnaire for reported symptoms and associated demographic data were 92% in Lake Munmorah and 93% in Dungog, with 84% and 90% of children respectively being measured for lung function, atopy, and bronchial reactivity. There were 419 boys and 432 girls aged 5 to 12 years. Main outcome measures were current wheeze and bronchial hyper-reactivity, defined as a fall in forced expiratory volume in 1 second (FEV1) or peak expiratory flow (PEF) of 20% or more. Current wheeze was reported in 24.8% of the Lake Munmorah children compared with 14.6% of the Dungog children. Bronchial hyper-reactivity was similar for both groups--25.2% in Lake Munmorah and 22.3% in Dungog. The mean baseline FEV1 was lower in Lake Munmorah than in Dungog (p power station town, but bronchial hyper-reactivity and skin test defined atopy were similar in the two communities. These results are consistent with the previous study and confirm the increased presence of reported symptomatic illness in the town near power stations.

  15. Increased theta band EEG power in sickle cell disease patients

    Directory of Open Access Journals (Sweden)

    Case M

    2017-12-01

    Full Text Available Michelle Case,1 Sina Shirinpour,1 Huishi Zhang,1 Yvonne H Datta,2 Stephen C Nelson,3 Karim T Sadak,4 Kalpna Gupta,2 Bin He1,5 1Department of Biomedical Engineering, 2Department of Medicine, University of Minnesota, 3Pediatric Hematology-Oncology, Children’s Hospitals and Clinics of Minnesota, 4Pediatric Hematology-Oncology, University of Minnesota Masonic Children’s Hospital, 5Institute for Engineering in Medicine, University of Minnesota, Minneapolis, MN, USA Objective: Pain is a major issue in the care of patients with sickle cell disease (SCD. The mechanisms behind pain and the best way to treat it are not well understood. We studied how electroencephalography (EEG is altered in SCD patients. Methods: We recruited 20 SCD patients and compared their resting state EEG to that of 14 healthy controls. EEG power was found across frequency bands using Welch’s method. Electrophysiological source imaging was assessed for each frequency band using the eLORETA algorithm. Results: SCD patients had increased theta power and decreased beta2 power compared to controls. Source localization revealed that areas of greater theta band activity were in areas related to pain processing. Imaging parameters were significantly correlated to emergency department visits, which indicate disease severity and chronic pain intensity. Conclusion: The present results support the pain mechanism referred to as thalamocortical dysrhythmia. This mechanism causes increased theta power in patients. Significance: Our findings show that EEG can be used to quantitatively evaluate differences between controls and SCD patients. Our results show the potential of EEG to differentiate between different levels of pain in an unbiased setting, where specific frequency bands could be used as biomarkers for chronic pain. Keywords: sickle cell disease, electroencephalography, chronic pain, electrophysiological source imaging, thalamocortical dysrhythmia

  16. Net energy analysis - powerful tool for selecting elective power options

    Energy Technology Data Exchange (ETDEWEB)

    Baron, S. [Brookhaven National Laboratory, Upton, NY (United States)

    1995-12-01

    A number of net energy analysis studies have been conducted in recent years for electric power production from coal, oil and uranium fuels; synthetic fuels from coal and oil shale; and heat and electric power from solar energy. This technique is an excellent indicator of investment costs, environmental impact and potential economic competitiveness of alternative electric power systems for energy planners from the Eastern European countries considering future options. Energy conservation is also important to energy planners and the net energy analysis technique is an excellent accounting system on the extent of energy resource conservation. The author proposes to discuss the technique and to present the results of his studies and others in the field. The information supplied to the attendees will serve as a powerful tool to the energy planners considering their electric power options in the future.

  17. POWER GRID DYNAMICS: ENHANCING POWER SYSTEM OPERATION THROUGH PRONY ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Ray, C.; Huang, Z.

    2007-01-01

    Prony Analysis is a technique used to decompose a signal into a series consisting of weighted complex exponentials and promises to be an effi cient way of recognizing sensitive lines during faults in power systems such as the U.S. Power grid. Positive Sequence Load Flow (PSLF) was used to simulate the performance of a simple two-area-four-generator system and the reaction of the system during a line fault. The Dynamic System Identifi cation (DSI) Toolbox was used to perform Prony analysis and use modal information to identify key transmission lines for power fl ow adjustment to improve system damping. The success of the application of Prony analysis methods to the data obtained from PSLF is reported, and the key transmission line for adjustment is identifi ed. Future work will focus on larger systems and improving the current algorithms to deal with networks such as large portions of the Western Electricity Coordinating Council (WECC) power grid.

  18. Increased photovoltaic power output via diffractive spectrum separation.

    Science.gov (United States)

    Kim, Ganghun; Dominguez-Caballero, Jose A; Lee, Howard; Friedman, Daniel J; Menon, Rajesh

    2013-03-22

    In this Letter, we report the preliminary demonstration of a new paradigm for photovoltaic power generation that utilizes a broadband diffractive-optical element (BDOE) to efficiently separate sunlight into laterally spaced spectral bands. These bands are then absorbed by single-junction photovoltaic cells, whose band gaps correspond to the incident spectral bands. We designed such BDOEs by utilizing a modified version of the direct-binary-search algorithm. Gray scale lithography was used to fabricate these multilevel optics. They were experimentally characterized with an overall optical efficiency of 70% over a wavelength range of 350-1100 nm, which was in excellent agreement with simulation predictions. Finally, two prototype devices were assembled: one with a pair of copper indium gallium selenide based photovoltaic devices, and another with GaAs and c-Si photovoltaic devices. These devices demonstrated an increase in output peak electrical power of ∼ 42% and ∼ 22%, respectively, under white-light illumination. Because of the optical versatility and manufacturability of the proposed BDOEs, the reported spectrum-splitting approach provides a new approach toward low-cost solar power.

  19. Modelling of electrical power systems for power flow analysis

    Energy Technology Data Exchange (ETDEWEB)

    Cogo, Joao Roberto [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1994-12-31

    The industry systems in Brazil are responsible for a consumption of over 50% (fifty per cent) of the total electrical power generated: therefore, they are import loads in power flow studies, and their modeling should be as much the best. Usually, in power flow studies, the industry systems are modeled by taking the influence of the power (active and reactive) and of the current on the voltage into account. Since the inducting motors, within the industry systems, represent at least 50% (fifty per cent) of the power consumption, and a large part of them is oversize, it is proposed to represent the industry systems as a function of the characteristic of power on shaft versus voltage into account. Since the induction motors, within the industry systems, represent at least 50% (fifty per cent) of the power consumption, and a large part of them is oversized, it is proposed to represent the industry systems as a function of the characteristics of power on shaft versus voltage for the analysis of power systems, aiming a load flow study. Thereafter, a model of an equivalent motor which has a basis the typical performance curve of an induction motor is present. This model is obtained from empirical parameters, surveyed from a population of over 1000 motors. (author) 3 refs., 1 fig., 4 tabs.

  20. Analysis of a solar powered absorption system

    International Nuclear Information System (INIS)

    Said, S.A.M.; El-Shaarawi, M.A.I.; Siddiqui, M.U.

    2015-01-01

    Highlights: • Conventional absorption system modified to increase COP. • Results indicated increase of 10% in COP due to dephlegmator heat recovery. • Results indicated increase of 8% in COP due to refrigerant storage unit. • Results indicated increase of 18% in COP due to combined effect of modifications. • Simulation results indicated a very good agreement with the measured results. - Abstract: Today, fossil fuel is the primary extensively used source of energy. However, its negative impact on the environment have forced the energy research continuity to seriously consider renewable sources of energy. Solar energy, in particular, has been the main focus in this regard because it is a source of clean energy and naturally available. This study presents the design and analysis of a solar powered absorption refrigeration system modified to increase its coefficient of performance (COP). The modifications include recovering of waste heat from a dephlegmator and utilization of a refrigerant storage unit. The simulation results indicate an increase of 10% in the COP of the conventional design using dephlegmator heat recovery and an increase of 8% in the COP of the conventional design due to the use of a refrigerant storage. The analysis for the combined effect of modifications indicates an increase of 18% in the COP compared to conventional design. Calculated values of coefficient of performance indicate a very good agreement with the ones obtained based on measurement

  1. Financial analysis of wind power projects

    International Nuclear Information System (INIS)

    Juanico, Luis E.; Bergallo, Juan E.

    1999-01-01

    In this work a financial assessment of the economic competitiveness of wind power projects in Argentina compared with other no CO 2 emission sources, such as nuclear, was developed. Argentina has a market driven electrical grid system, and no greenhouse gas emissions penalty taxes, together with a very low natural gas cost and a sustained nuclear development program. For the financial analysis an average wind velocity source of 8 m/s, on several wind farms (from 2 machines to 60) built with new technology wind generators (750 kilowatts power, 900 dollar/kilowatt cost) operating over 20 years, was considered. The leveled cost obtained is decreasing while the number of machines is increasing, from 0,130 dollar/kilowatt-hour to 0,090 dollar/kilowatts-hour. This poor performance can be partially explained considering the higher interest rates in the argentine financial market (15%) than the ones in developed countries

  2. Supplement analysis, Southpoint power project

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-16

    The Calpine Corporation applied to interconnect its proposed power plant with the Western Area Power Administration`s (Western) Parker-Davis project in western Arizona. Western, as a major electric transmission system owner is required by existing policies and regulations, to provide access to its transmission system, when requested by an eligible organization. The proposed interconnection would integrate a major source of new generation into the Parker-Davis system which would allow Calpine to supply its power to the electric wholesale market. Based on this application, Western`s proposed action is to enter into an interconnection agreement with Calpine.

  3. Energy analysis and projecting of power plants

    International Nuclear Information System (INIS)

    Jirlow, K.

    1975-01-01

    Energy analysis aims at a better explanation of energy flow and energy exchange at different production processes. In this report the energy budget is analysed for separate nuclear power plants and for expanding systems of power plants. A mathematical model is developed for linear and exponential expanding of nuclear power. The profitableness for nuclear power plants in Sweden is considered to be good. (K.K.)

  4. Impact of Production from Photovoltaic Power Plants on Increase of Ancillary Services in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Martin Smocek

    2016-01-01

    Full Text Available Renewable energy resources represent a noticeable part of the overall energetic concept development. New integration of renewable energy resources into power grids has a significant impact on the reliability and quality of power supply. The major problem of the photovoltaic and wind power plants is their dependency on weather conditions, since it has a direct effect on their immediate output produced that shows stochastic behaviour. These stochastic outputs result in very adverse impacts on the power grid. Further development of these resources could lead to exceeding of the control and absorption abilities of the power grid. The power grid must be set in balance with respect to the production and consumption of electric power at any time. The operation of photovoltaic power plants impair keeping this balance. That has an adverse impact on the very operation and maintenance of network parameters within the extent required. This survey deals with analysis focused on operation of the photovoltaic power plants with respect to the increase of reserve power in ancillary services in the Czech Republic.

  5. Power system reliability analysis using fault trees

    International Nuclear Information System (INIS)

    Volkanovski, A.; Cepin, M.; Mavko, B.

    2006-01-01

    The power system reliability analysis method is developed from the aspect of reliable delivery of electrical energy to customers. The method is developed based on the fault tree analysis, which is widely applied in the Probabilistic Safety Assessment (PSA). The method is adapted for the power system reliability analysis. The method is developed in a way that only the basic reliability parameters of the analysed power system are necessary as an input for the calculation of reliability indices of the system. The modeling and analysis was performed on an example power system consisting of eight substations. The results include the level of reliability of current power system configuration, the combinations of component failures resulting in a failed power delivery to loads, and the importance factors for components and subsystems. (author)

  6. Power Analysis Software for Educational Researchers

    Science.gov (United States)

    Peng, Chao-Ying Joanne; Long, Haiying; Abaci, Serdar

    2012-01-01

    Given the importance of statistical power analysis in quantitative research and the repeated emphasis on it by American Educational Research Association/American Psychological Association journals, the authors examined the reporting practice of power analysis by the quantitative studies published in 12 education/psychology journals between 2005…

  7. Core design experience of WWER-440 reactors when they working on increased power level

    International Nuclear Information System (INIS)

    Adeev, V.; Panov, A.; Melenchuk, I.

    2015-01-01

    The Kola NPP continues commercial operation of 2nd generation fuel (FA-2) and trial operation of 3rd generation fuel (FA-3), which has a number of design features providing the best operational characteristics. This report gives the results of VVER-440 core operation with FA-2 and FA-3 with enrichment increased up to 4.87%, and at the power level uprated to 107% of nominal power level. Brief analysis of obtained data is carried out. Peculiarities and techniques of developing loading patterns with new types of nuclear fuel for operation at the uprated power level are reviewed. (authors)

  8. Computer-aided power systems analysis

    CERN Document Server

    Kusic, George

    2008-01-01

    Computer applications yield more insight into system behavior than is possible by using hand calculations on system elements. Computer-Aided Power Systems Analysis: Second Edition is a state-of-the-art presentation of basic principles and software for power systems in steady-state operation. Originally published in 1985, this revised edition explores power systems from the point of view of the central control facility. It covers the elements of transmission networks, bus reference frame, network fault and contingency calculations, power flow on transmission networks, generator base power setti

  9. An Effective Distributed Model for Power System Transient Stability Analysis

    Directory of Open Access Journals (Sweden)

    MUTHU, B. M.

    2011-08-01

    Full Text Available The modern power systems consist of many interconnected synchronous generators having different inertia constants, connected with large transmission network and ever increasing demand for power exchange. The size of the power system grows exponentially due to increase in power demand. The data required for various power system applications have been stored in different formats in a heterogeneous environment. The power system applications themselves have been developed and deployed in different platforms and language paradigms. Interoperability between power system applications becomes a major issue because of the heterogeneous nature. The main aim of the paper is to develop a generalized distributed model for carrying out power system stability analysis. The more flexible and loosely coupled JAX-RPC model has been developed for representing transient stability analysis in large interconnected power systems. The proposed model includes Pre-Fault, During-Fault, Post-Fault and Swing Curve services which are accessible to the remote power system clients when the system is subjected to large disturbances. A generalized XML based model for data representation has also been proposed for exchanging data in order to enhance the interoperability between legacy power system applications. The performance measure, Round Trip Time (RTT is estimated for different power systems using the proposed JAX-RPC model and compared with the results obtained using traditional client-server and Java RMI models.

  10. Model Based Open-Loop Wind Farm Control Using Active Power for Power Increase and Load Reduction

    OpenAIRE

    Hyungyu Kim; Kwansu Kim; Insu Paek

    2017-01-01

    A new wind farm control algorithm that adjusts the power output of the most upstream wind turbine in a wind farm for power increase and load reduction was developed in this study. The algorithm finds power commands to individual wind turbines to maximize the total power output from the wind farm when the power command from the transmission system operator is larger than the total available power from the wind farm. To validate this wind farm control algorithm, a relatively high fidelity wind ...

  11. Innovative Method of the Power Analysis

    Directory of Open Access Journals (Sweden)

    Z. Martinasek

    2013-06-01

    Full Text Available This paper describes an innovative method of the power analysis which presents the typical example of successful attacks against trusted cryptographic devices such as RFID (Radio-Frequency IDentifications and contact smart cards. The proposed method analyzes power consumption of the AES (Advanced Encryption Standard algorithm with neural network, which successively classifies the first byte of the secret key. This way of the power analysis is an entirely new approach and it is designed to combine the advantages of simple and differential power analysis. In the extreme case, this feature allows to determine the whole secret key of a cryptographic module only from one measured power trace. This attribute makes the proposed method very attractive for potential attackers. Besides theoretical design of the method, we also provide the first implementation results. We assume that the method will be certainly optimized to obtain more accurate classification results in the future.

  12. Statistical power analysis for the behavioral sciences

    National Research Council Canada - National Science Library

    Cohen, Jacob

    1988-01-01

    ... offers a unifying framework and some new data-analytic possibilities. 2. A new chapter (Chapter 11) considers some general topics in power analysis in more integrted form than is possible in the earlier...

  13. Statistical power analysis for the behavioral sciences

    National Research Council Canada - National Science Library

    Cohen, Jacob

    1988-01-01

    .... A chapter has been added for power analysis in set correlation and multivariate methods (Chapter 10). Set correlation is a realization of the multivariate general linear model, and incorporates the standard multivariate methods...

  14. Dynamic Wireless Power Transfer - Grid Impacts Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Markel, Tony; Meintz, Andrew; Gonder, Jeff

    2015-12-04

    This presentation discusses the current status of analysis of the electricity grid impacts of a dynamic wireless power transfer system deployed to the Atlanta region on select high traffic roadway segments.

  15. Increase of Ship Power Plants Gas-Air Cooler Efficiency

    Directory of Open Access Journals (Sweden)

    Dymo B.V.

    2017-08-01

    Full Text Available Results of theoretical and experimental study of a gas-air cooler used to reduce the temperature of the exhaust gases of engines and boilers of ship power plants and the heat radiation of the chimney are presented in this paper. A Computational Fluid Dynamic (CFD model of the gas-air cooler designed as an inhomogeneous ejector with a nozzle apparatus was developed. As a result of numerical simulation, the fields of temperature, pressure and velocity distributions along the gas-air cooler cross-sections were obtained. An experimental study of working model of the gas-air cooler at a scale of 1:5 was carried out. In the self-similarity region, characterized by Reynolds numbers (3.0-3.8·105, the values of the resistance coefficient of the gas-air cooler model in the confidence interval ± 4.4 % fit on the line ςм = 2.52. A comparative analysis of the characteristics of gas-air flow, obtained during numerical simulation, with the results of thermal testing of working model of the gas-air cooler is given. The error in calculating of gas-air mixture temperature at the exit section of the gas-air cooler at 100 % load is 4.6 %. The CFD-modeling allows making calculations and optimization of new designs of the gas-air cooler at the design stage without carrying out thermal engineering tests both in the main and partial modes of operation.

  16. Computational methods in power system analysis

    CERN Document Server

    Idema, Reijer

    2014-01-01

    This book treats state-of-the-art computational methods for power flow studies and contingency analysis. In the first part the authors present the relevant computational methods and mathematical concepts. In the second part, power flow and contingency analysis are treated. Furthermore, traditional methods to solve such problems are compared to modern solvers, developed using the knowledge of the first part of the book. Finally, these solvers are analyzed both theoretically and experimentally, clearly showing the benefits of the modern approach.

  17. Focus: Increasing profitability from powerful assets. Annual report for 1998

    International Nuclear Information System (INIS)

    1999-01-01

    Report on operations at the end of fiscal year 1998 and on the year-end financial position of PanCanadian Petroleum Limited is provided. By all accounts the company had a successful year: increased production by seven percent to 796 mmcf/day, making the company the largest publicly traded gas producer in Canada; ranked as one of lowest-cost producers in western Canada with average operating costs of $ 0.37/mcf; drilled 1,081 new wells at a success rate of 85 per cent and increased royalty interest production five per cent to an average of 26,700 barrels of oil equivalent per day. Other achievements included drilling in Nova Scotia, land and license aquisition in the Gulf of Mexico and in the North Sea respectively, acquisition of a 15 per cent interest in two exploration blocks off the Ivory Coast in West Africa, refining of proprietory seismic technologies developed in recent years, reduction of average well costs by 10 per cent by using new drill bit technology, consolidation of Canadian and American natural gas marketing groups to increase market access across North America, and management reorganization of the Heavy Oil Business Unit. In addition to details of these and other achievements, the report also contains management analysis of key business results, the consolidated financial statements and various operating and financial statistics and results

  18. Hydrogen-oxygen steam generator applications for increasing the efficiency, maneuverability and reliability of power production

    Science.gov (United States)

    Schastlivtsev, A. I.; Borzenko, V. I.

    2017-11-01

    The comparative feasibility study of the energy storage technologies showed good applicability of hydrogen-oxygen steam generators (HOSG) based energy storage systems with large-scale hydrogen production. The developed scheme solutions for the use of HOSGs for thermal power (TPP) and nuclear power plants (NPP), and the feasibility analysis that have been carried out have shown that their use makes it possible to increase the maneuverability of steam turbines and provide backup power supply in the event of failure of the main steam generating equipment. The main design solutions for the integration of hydrogen-oxygen steam generators into the main power equipment of TPPs and NPPs, as well as their optimal operation modes, are considered.

  19. Thermoeconomic analysis of power plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tsatsaronis, G.; Winhold, M.

    1984-08-01

    In this report, the concept of exergy and the general methodology of the exergetic analysis and the thermoeconomic (combined exergetic and economic) analysis of energy conversion systems are presented. The THESIS (THermodynamic and Economc SImulation System) computer program used for these analyses is briefly described. Detailed mass, energy, exergy and money balances for a reference steam power plant (Harry Allen Station) are shown. The effect of the most important process parameters on the overall efficiency is investigated. A year-by-year and a levelized revenue requirement analysis are presented. The costs of exergy losses are compared with the capital costs and other expenses due to owning and operating each particular plant component. The question whether it is profitable to reduce the exergy losses by increasing these costs and vice versa is investigated. A cost sensitivity analysis including the effect of coal price and average annual capacity factor is performed. The methodology applied in this report appears to be useful in analyzing and evaluating energy conversion systems. The analyses presented here allow identification and evaluation of the inefficiencies and the opportunities for improvement of an energy conversion process. Results indicate that modifications in certain process parameters can lead to a decrease in the cost of electricity produced by the reference plant.

  20. Safety Analysis for Power Reactor Protection System

    International Nuclear Information System (INIS)

    Eisawy, E.A.; Sallam, H.

    2012-01-01

    The main function of a Reactor Protection System (RPS) is to safely shutdown the reactor and prevents the release of radioactive materials. The purpose of this paper is to present a technique and its application for used in the analysis of safety system of the Nuclear Power Plant (NPP). A more advanced technique has been presented to accurately study such problems as the plant availability assessments and Technical Specifications evaluations that are becoming increasingly important. The paper provides the Markov model for the Reactor Protection System of the NPP and presents results of model evaluations for two testing policies in technical specifications. The quantification of the Markov model provides the probability values that the system will occupy each of the possible states as a function of time.

  1. Seismic analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Halbritter, A.L.

    1984-01-01

    Nuclear Power Plants require exceptional safety guarantees which are reflected in a rigorous control of the employed materials, advanced construction technology, sophisticated methods of analysis and consideration of non conventional load cases such as the earthquake loading. In this paper, the current procedures used in the seismic analysis of Nuclear Power Plants are presented. The seismic analysis of the structures has two objectives: the determination of forces in the structure in order to design it against earthquakes and the generation of floor response spectra to be used in the design of mechanical and electrical components and piping systems. (Author) [pt

  2. Does green consumerism increase the acceptance of wind power?

    DEFF Research Database (Denmark)

    Thøgersen, John; Noblet, Caroline

    2012-01-01

    based on a random sample of residents of the state of Maine, USA, we find that both everyday ‘‘ green ’’ behaviour and the acceptance of an expansion of wind power are rooted in environmental concern and that everyday ‘‘green’’ behaviour gives a significant contribution to predicting acceptance of wind...

  3. Effects of High Intensity Interval Training on Increasing Explosive Power, Speed, and Agility

    Science.gov (United States)

    Fajrin, F.; Kusnanik, N. W.; Wijono

    2018-01-01

    High Intensity Interval Training (HIIT) is a type of exercise that combines high-intensity exercise and low intensity exercise in a certain time interval. This type of training is very effective and efficient to improve the physical components. The process of improving athletes achievement related to how the process of improving the physical components, so the selection of a good practice method will be very helpful. This study aims to analyze how is the effects of HIIT on increasing explosive power, speed, and agility. This type of research is quantitative with quasi-experimental methods. The design of this study used the Matching-Only Design, with data analysis using the t-test (paired sample t-test). After being given the treatment for six weeks, the results showed there are significant increasing in explosive power, speed, and agility. HIIT in this study used a form of exercise plyometric as high-intensity exercise and jogging as mild or moderate intensity exercise. Increase was due to the improvement of neuromuscular characteristics that affect the increase in muscle strength and performance. From the data analysis, researchers concluded that, Exercises of High Intensity Interval Training significantly effect on the increase in Power Limbs, speed, and agility.

  4. Structural dynamic analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Halbritter, A.L.; Koishi, N.; Prates, C.L.M.

    1986-01-01

    One of the most important items to be considered in order to guarantee the safety conditions of a Nuclear Power Plant is the design of the civil structures, the electrical and mechanical components and piping system taking into account non-conventional loading cases, e.g. earthquakes and explosions pressure waves. The general procedures used in the structural dynamic analysis of Nuclear Power Plants are presented, specially for seismic and explosion loads. (Author) [pt

  5. Probability analysis of nuclear power plant hazards

    International Nuclear Information System (INIS)

    Kovacs, Z.

    1985-01-01

    The probability analysis of risk is described used for quantifying the risk of complex technological systems, especially of nuclear power plants. Risk is defined as the product of the probability of the occurrence of a dangerous event and the significance of its consequences. The process of the analysis may be divided into the stage of power plant analysis to the point of release of harmful material into the environment (reliability analysis) and the stage of the analysis of the consequences of this release and the assessment of the risk. The sequence of operations is characterized in the individual stages. The tasks are listed which Czechoslovakia faces in the development of the probability analysis of risk, and the composition is recommended of the work team for coping with the task. (J.C.)

  6. Unraveling protein networks with power graph analysis.

    Directory of Open Access Journals (Sweden)

    Loïc Royer

    Full Text Available Networks play a crucial role in computational biology, yet their analysis and representation is still an open problem. Power Graph Analysis is a lossless transformation of biological networks into a compact, less redundant representation, exploiting the abundance of cliques and bicliques as elementary topological motifs. We demonstrate with five examples the advantages of Power Graph Analysis. Investigating protein-protein interaction networks, we show how the catalytic subunits of the casein kinase II complex are distinguishable from the regulatory subunits, how interaction profiles and sequence phylogeny of SH3 domains correlate, and how false positive interactions among high-throughput interactions are spotted. Additionally, we demonstrate the generality of Power Graph Analysis by applying it to two other types of networks. We show how power graphs induce a clustering of both transcription factors and target genes in bipartite transcription networks, and how the erosion of a phosphatase domain in type 22 non-receptor tyrosine phosphatases is detected. We apply Power Graph Analysis to high-throughput protein interaction networks and show that up to 85% (56% on average of the information is redundant. Experimental networks are more compressible than rewired ones of same degree distribution, indicating that experimental networks are rich in cliques and bicliques. Power Graphs are a novel representation of networks, which reduces network complexity by explicitly representing re-occurring network motifs. Power Graphs compress up to 85% of the edges in protein interaction networks and are applicable to all types of networks such as protein interactions, regulatory networks, or homology networks.

  7. Power calculator for instrumental variable analysis in pharmacoepidemiology.

    Science.gov (United States)

    Walker, Venexia M; Davies, Neil M; Windmeijer, Frank; Burgess, Stephen; Martin, Richard M

    2017-10-01

    Instrumental variable analysis, for example with physicians' prescribing preferences as an instrument for medications issued in primary care, is an increasingly popular method in the field of pharmacoepidemiology. Existing power calculators for studies using instrumental variable analysis, such as Mendelian randomization power calculators, do not allow for the structure of research questions in this field. This is because the analysis in pharmacoepidemiology will typically have stronger instruments and detect larger causal effects than in other fields. Consequently, there is a need for dedicated power calculators for pharmacoepidemiological research. The formula for calculating the power of a study using instrumental variable analysis in the context of pharmacoepidemiology is derived before being validated by a simulation study. The formula is applicable for studies using a single binary instrument to analyse the causal effect of a binary exposure on a continuous outcome. An online calculator, as well as packages in both R and Stata, are provided for the implementation of the formula by others. The statistical power of instrumental variable analysis in pharmacoepidemiological studies to detect a clinically meaningful treatment effect is an important consideration. Research questions in this field have distinct structures that must be accounted for when calculating power. The formula presented differs from existing instrumental variable power formulae due to its parametrization, which is designed specifically for ease of use by pharmacoepidemiologists. © The Author 2017. Published by Oxford University Press on behalf of the International Epidemiological Association

  8. Power and performance software analysis and optimization

    CERN Document Server

    Kukunas, Jim

    2015-01-01

    Power and Performance: Software Analysis and Optimization is a guide to solving performance problems in modern Linux systems. Power-efficient chips are no help if the software those chips run on is inefficient. Starting with the necessary architectural background as a foundation, the book demonstrates the proper usage of performance analysis tools in order to pinpoint the cause of performance problems, and includes best practices for handling common performance issues those tools identify. Provides expert perspective from a key member of Intel's optimization team on how processors and memory

  9. Dynamic security issues in autonomous power systems with increasing wind power penetration

    DEFF Research Database (Denmark)

    Margaris, I.D.; Hansen, Anca Daniela; Sørensen, Poul Ejnar

    2011-01-01

    Asynchronous Generator (DFAG) and Permanent Magnet Synchronous Generator (PMSG) – are applied and issues regarding interaction with the power system are investigated. This paper provides conclusions about the dynamic security of non-interconnected power systems with high wind power penetration based...... as for the wind farms are therefore essential for power system studies related to these issues, especially when applied to non interconnected systems with high wind power penetration. Detailed generic models for three different wind turbine technologies – Active Stall Induction Generator (ASIG), Doubly Fed...

  10. Bulk outlet temperature limits and increased reactor power levels

    Energy Technology Data Exchange (ETDEWEB)

    Jones, S.S.

    1958-06-13

    In a recent report, means of circumventing the present bulk temperature limits are suggested. These have definite merit but do not present an over-all picture of the problem. Therefore, this bulk temperature limit is reviewed in order to place the problem in its full perspective. A program of action is suggested that should lead to: Revised operating conditions and process piping to obtain higher power levels at the same bulk outlet temperature; The completion of production tests to permit higher bulk outlet temperatures with no significant changes in reactor piping; or Redesign of the effluent system to eliminate bulk temperatures as a reactor operating limit.

  11. Comparative analysis of distributed power control algorithms in CDMA

    OpenAIRE

    Abdulhamid, Mohanad F.

    2017-01-01

    This paper presents comparative analysis of various algorithms of distributed power control used in Code Division Multiple Access (CDMA) systems. These algorithms include Distributed Balancing power control algorithm (DB), Modified Distributed Balancing power control algorithm (MDB), Fully Distributed Power Control algorithm (FDPC), Distributed Power Control algorithm (DPC), Distributed Constrained Power Control algorithm (DCPC), Unconstrained Second-Order Power Control algorithm (USOPC), Con...

  12. Increasing flexibility of coal power plant by control system modifications

    Directory of Open Access Journals (Sweden)

    Marušić Ante

    2016-01-01

    Full Text Available Expanding implementation of intermittent renewable energy sources has already started to change the role of thermal power plants in energy systems across Europe. Traditionally base load plants are now forced to operate as peaking plants. A familiar transition in upcoming years is expected in Croatia and coal power plant operators are preparing accordingly. To evaluate cycling capabilities and control system operation for flexible operation of selected 210 MW coal plant, series of tests with different load gradients were performed and results were thoroughly analyzed. Two possible “bottlenecks” are identified, thermal stress in superheater header, and achievable ramping rate considering operational limitations of coal feeders, firing system and evaporator dynamics. Several unexpected readings were observed, usually caused by malfunctioning sensors and equipment, resulting in unexpected oscillations of superheated steam temperature. Based on superheater geometry and experimental data, maximal steam temperature gradient during ramping was evaluated. Since thermal stress was well inside the safety margins, the simulation model of the whole boiler was used to evaluate achievable ramping on electric side.

  13. Operating modes and practical power flow analysis of bidirectional isolated power interface for distributed power systems

    International Nuclear Information System (INIS)

    Wen, Huiqing; Su, Bin

    2016-01-01

    Highlights: • Four operating modes of Dual-Phase-Shift control for Dual Active Bridge converter are presented. • Effects of “minor parameters” such as the deadtime and power device voltage drops are analyzed. • Accurate power flow models with Dual-Phase-Shift control are developed and verified with experimental results. • Optimal operating mode is determined with respect to the efficiency improvement. • Measured efficiency of the Dual Active Bridge converter is improved up to 14%. - Abstract: Due to the intermittent nature of the renewable energy sources including photovoltaic and wind energy, the energy storage systems are essential to stabilize dc bus voltage. Considering the discharge depth of super-capacitors and energy-storage batteries, the bidirectional isolated power interface will operate for a wide range of voltage and power. This study focuses on in-depth analysis of the dual-active-bridge dc–dc converter that is controlled by the dual-phase-shift scheme to improve the conversion efficiency in distributed power system. The power flow of each operating mode with dual-phase-shift control is characterized based on a detailed analysis of the effects of “minor parameters”, including the deadtime and power device voltage drops. The complete output power plane of the dual-active-bridge converter with dual-phase-shift control is obtained and compared with experimental results. The optimal operating mode is determined according to the practical output power range and the power flow characteristics. Experimental evaluation shows the effectiveness of the proposed power flow model with dual-phase-shift control and significant efficiency improvement using the optimal mode of dual-phase-shift compared with the conventional phase shift control.

  14. Power Estimation in Multivariate Analysis of Variance

    Directory of Open Access Journals (Sweden)

    Jean François Allaire

    2007-09-01

    Full Text Available Power is often overlooked in designing multivariate studies for the simple reason that it is believed to be too complicated. In this paper, it is shown that power estimation in multivariate analysis of variance (MANOVA can be approximated using a F distribution for the three popular statistics (Hotelling-Lawley trace, Pillai-Bartlett trace, Wilk`s likelihood ratio. Consequently, the same procedure, as in any statistical test, can be used: computation of the critical F value, computation of the noncentral parameter (as a function of the effect size and finally estimation of power using a noncentral F distribution. Various numerical examples are provided which help to understand and to apply the method. Problems related to post hoc power estimation are discussed.

  15. Investigation and analysis of industrial power meters in industrial plant

    Energy Technology Data Exchange (ETDEWEB)

    Pretorius, J.H.C.; Modipane, K.C.; Dewerajram, H. [Johannesburg Univ. (South Africa). Dept. of Electrical and Electronic Engineering Science

    2008-07-01

    An increase in the harmonics produced by electrical equipment is having a significant impact on the power quality of electrical networks. An analysis of industrial power meters in the presence of unbalanced 3-phase systems and harmonics was presented. The meters were used to analyze the alternating current systems of 2 networks coupled to the same bus. Measurements were taken at the generator, on the primary side of the 400 V/11 kV step-up, and after the motor-generator set transformer. The active, reactive, and apparent power calculations of a power meter and a reference Institute of Electrical and Electronic Engineers (IEEE) power meter were presented. Current and voltage waveforms were compared. The evaluation demonstrated a significant difference in reactive power as a result of the different reactive power calculation methods. A further comparison with a different meter demonstrated significant differences in phase value calculations. Results of the study suggested that the accuracy of power meters is influenced by the calculation methods used. Further studies are needed to assess the accuracy of reactive power measurements for power meters. 8 refs., 4 tabs., 4 figs.

  16. Wind power externalities: A meta-analysis

    NARCIS (Netherlands)

    Mattmann, M.; Logar, I.; Brouwer, R.

    2016-01-01

    This study presents the first quantitative meta-analysis of the non-market valuation literature on the external effects associated with wind power production. A data set of 60 observations drawn from 32 studies is constructed. The relative economic values of different types of externalities as well

  17. EXERGETIC ANALYSIS OF A COGENERATION POWER PLANT

    Directory of Open Access Journals (Sweden)

    Osvaldo Manuel Nuñez Bosch

    2016-07-01

    Full Text Available Cogeneration power plants connected to industrial processes have a direct impact on the overall efficiency of the plant and therefore on the economic results. Any modification to the thermal outline of these plants must first include an exergetic analysis to compare the benefits it can bring the new proposal. This research is performed to a cogeneration plant in operation with an installed electrical capacity of 24 MW and process heat demand of 190 MW, it shows a study made from the Second Law of Thermodynamics. Exergetic evaluation of each component of the plant was applied and similarly modified cogeneration scheme was evaluated. The results illustrate that the exergy losses and irreversibilities are completely different from one subsystem to another. In general, the total exergy destruction represented 70,7% from the primary fuel exergy. Steam generator was the subsystem with the highest irreversibility of the plant with 54%. It was demonstrated that the increase of the steam parameters lead to reduce exergy destruction and exergy efficiency elevation. The suppression of the reduction system and the adding of an extraction-condensing steam turbine produce the same effect and contribute to drop off the electrical consumption from the grid.

  18. Having the Power to Forgive: When the Experience of Power Increases Interpersonal Forgiveness

    NARCIS (Netherlands)

    Karremans, J.C.T.M.; Smith, P.K.

    2010-01-01

    The present research examined the association between power, defined in terms of experienced control over outcomes and resources in a relationship, and interpersonal forgiveness. Based on recent findings in the literature suggesting that power is associated with goal directedness, it was

  19. Increased durability concrete for generation of pillars power lines

    Directory of Open Access Journals (Sweden)

    Yakovlev Grigory

    2016-01-01

    Full Text Available In this researches multilayered carbon nanotubes of production of the French corporation “Arkema” were used. It has followed features: diameter of 10-15 nanometers and up to 15 microns long. Multilayered carbon nanotubes were used for increasing of physics and technology properties of cement concrete. It was established that at introduction of multilayered carbon nanotubes in amount of 0.006% of the mass led concrete durability increases by 28%, resistance to frost from F200 to F400, tightness to water from W8 to W14.

  20. Power Systems Life Cycle Analysis Tool (Power L-CAT).

    Energy Technology Data Exchange (ETDEWEB)

    Andruski, Joel; Drennen, Thomas E.

    2011-01-01

    The Power Systems L-CAT is a high-level dynamic model that calculates levelized production costs and tracks environmental performance for a range of electricity generation technologies: natural gas combined cycle (using either imported (LNGCC) or domestic natural gas (NGCC)), integrated gasification combined cycle (IGCC), supercritical pulverized coal (SCPC), existing pulverized coal (EXPC), nuclear, and wind. All of the fossil fuel technologies also include an option for including carbon capture and sequestration technologies (CCS). The model allows for quick sensitivity analysis on key technical and financial assumptions, such as: capital, O&M, and fuel costs; interest rates; construction time; heat rates; taxes; depreciation; and capacity factors. The fossil fuel options are based on detailed life cycle analysis reports conducted by the National Energy Technology Laboratory (NETL). For each of these technologies, NETL's detailed LCAs include consideration of five stages associated with energy production: raw material acquisition (RMA), raw material transport (RMT), energy conversion facility (ECF), product transportation and distribution (PT&D), and end user electricity consumption. The goal of the NETL studies is to compare existing and future fossil fuel technology options using a cradle-to-grave analysis. The NETL reports consider constant dollar levelized cost of delivered electricity, total plant costs, greenhouse gas emissions, criteria air pollutants, mercury (Hg) and ammonia (NH3) emissions, water withdrawal and consumption, and land use (acreage).

  1. Influence on radiation protection when increasing the power in nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Erixon, S.; Oelander Guer, H. [Swedish Radiation Protection Authority, Stockholm (Sweden)

    2005-09-15

    An increase of thermal power has been accomplished in most Swedish nuclear power plants during the years, with an acceptable radiological impact. However in the future more and larger increase in power is planned. An increase of the power in the order of 20-30 % has been discussed. The purpose of this paper is to describe and discuss SSIs view on how and to what extent the increase of power will have influence on radiation protection issues such as occupational exposure, effluence and discharges and waste management (Summary-only contribution)

  2. Burnup analysis of the power reactor, 2

    International Nuclear Information System (INIS)

    Ezure, Hideo

    1975-09-01

    In burnup analysis of JPDR-1 with FLARE, it was found to have problems. The program FLORA was developed for solution of the problems. By their bench mark tests FLORA was found to be useful for three-dimensional thermal-hydro-dynamic analysis of BWRs. It was applied to analysis of the burnup of JPDR-1. The input data and option of FLORA were corrected on referring to the results of gammer probe tests for JPDR-1. The void, source and burnup distributions were calculated each month during the operation. The burnup distribution in three assemblies revealed by a destructive test agrees better with that by FLORA than by FLARE. It was shown that the distortion of power distribution around the control rods by FLORA was smaller and closer to that by the gammer probe tests than by FLARE, and the connector of fuel assemblies and the plugs in the reflector had much influence on the power distribution. (auth.)

  3. Application of ORC power station to increase electric power of gas compression ignition engine

    Directory of Open Access Journals (Sweden)

    Mocarski Szymon

    2017-01-01

    Full Text Available The paper presents the calculation results of efficiency of the subcritical low temperature ORC power station powered by waste heat resulting from the process of cooling a stationary compression ignition engine. The source of heat to supply the ORC power station is the heat in a form of water jet cooling the engine at a temperature of 92°C, and the exhaust gas stream at a temperature of 420°C. The study considers three variants of systems with the ORC power stations with different ways of using heat source. The first variant assumes using just engine cooling water to power the ORC station. In the second variant the ORC system is powered solely by a heat flux from the combustion gases by means of an intermediary medium - thermal oil, while the third variant provides the simultaneous management of both heat fluxes to heat the water stream as a source of power supply to the ORC station. The calculations were made for the eight working media belonging both to groups of so-called dry media (R218, R1234yf, R227ea and wet media (R32, R161, R152a, R134a, R22.

  4. Study on development system of increasing gearbox for high-performance wind-power generator

    Science.gov (United States)

    Xu, Hongbin; Yan, Kejun; Zhao, Junyu

    2005-12-01

    Based on the analysis of the development potentiality of wind-power generator and domestic manufacture of its key parts in China, an independent development system of the Increasing Gearbox for High-performance Wind-power Generator (IGHPWG) was introduced. The main elements of the system were studied, including the procedure design, design analysis system, manufacturing technology and detecting system, and the relative important technologies were analyzed such as mixed optimal joint transmission structure of the first planetary drive with two grade parallel axle drive based on equal strength, tooth root round cutting technology before milling hard tooth surface, high-precise tooth grinding technology, heat treatment optimal technology and complex surface technique, and rig test and detection technique of IGHPWG. The development conception was advanced the data share and quality assurance system through all the elements of the development system. The increasing Gearboxes for 600KW and 1MW Wind-power Generator have been successfully developed through the application of the development system.

  5. Analysis of thermal power calibration method

    International Nuclear Information System (INIS)

    Zagar, T.; Ravnik, M.; Persic, A.

    2000-01-01

    . Reactor power is in research reactors usually calibrated with accuracy of 10%. Calorimetric power calibration can be significantly wrong if it is performed under uncontrolled conditions. To measure correct temperature-rise rates, measurement should be performed at low reactor power, with concrete and air temperature equal to the bulk water temperature. Under controlled conditions corrections for heat loss are around 2%. But if calorimetric calibration is performed with high reactor power or with water temperature lower than concrete temperature, the error can be as big as 30%. This calibration is usually performed for some arbitrary chosen control rod configuration and is strictly valid for that configuration only. By introducing the flux perturbation factors a correction to the signal from the nuclear instrumentation is made, which practically eliminates the sensitivity of the control rod configuration. The analysis presented shows that the correction can be up to 15% in most unfavourable case, when the control rod closest to the detector is fully inserted

  6. Energy and exergy analysis of solar power tower plants

    International Nuclear Information System (INIS)

    Xu Chao; Wang Zhifeng; Li Xin; Sun Feihu

    2011-01-01

    Establishing the renewable electricity contribution from solar thermal power systems based on energy analysis alone cannot legitimately be complete unless the exergy concept becomes a part of that analysis. This paper presents a theoretical framework for the energy analysis and exergy analysis of the solar power tower system using molten salt as the heat transfer fluid. Both the energy losses and exergy losses in each component and in the overall system are evaluated to identify the causes and locations of the thermodynamic imperfection. Several design parameters including the direct normal irradiation (DNI), the concentration ratio, and the type of power cycle are also tested to evaluate their effects on the energy and exergy performance. The results show that the maximum exergy loss occurs in the receiver system, followed by the heliostat field system, although main energy loss occurs in the power cycle system. The energy and exergy efficiencies of the receiver and the overall system can be increased by increasing the DNI and the concentration ratio, but that increment in the efficiencies varies with the values of DNI and the concentration ratio. It is also found that the overall energy and exergy efficiencies of the solar tower system can be increased to some extent by integrating advanced power cycles including reheat Rankine cycles and supercritical Rankine cycles. - Highlights: →We presented a theoretical framework for the energy and exergy analysis of the solar tower system. →We tested the effects of several design parameters on the energy and exergy performance. →The maximum exergy loss occurs in the receiver system, followed by the heliostat field system. →Integrating advanced power cycles leads to increases in the overall energy and exergy efficiencies.

  7. DENINT power plant cost benefit analysis code: Analysis of methane fuelled power plant/district heating system

    International Nuclear Information System (INIS)

    Cincotti, V.; D'Andrea, A.

    1989-07-01

    The DENINT power plant cost benefit analysis code takes into consideration, not only power production costs at the generator terminals, but also, in the case of cogeneration, the costs of the fuel supply and heat and power distribution systems which depend greatly on the location of the plant. The code is able to allow comparisons of alternatives with varying annual operation hours, fuel cost increases, and different types of fossil fuels and production systems. For illustrative purposes, this paper examines two methane fired cogeneration plant/district heating alternatives

  8. Assessment and analysis of wind energy generation and power ...

    African Journals Online (AJOL)

    147. Assessment and analysis of wind energy generation and power control of wind turbine system. Évaluation et analyse de la production d'énergie éolienne et contrôle de puissances d'un .... balance between the increasing demand in energy and notably in ... very well fits of the wind distribution; flexible and scalable ...

  9. Energy analysis of nuclear power plants and their fuel cycle

    International Nuclear Information System (INIS)

    Held, C.; Moraw, G.; Schneeberger, M.; Szeless, A.

    1977-01-01

    Energy analysis has become an increasingly feasible and practical additional method for evaluating the engineering, economic and environmental aspects of power-producing systems. It compares total direct and indirect energy investment into construction and operation of power plants with their lifetime energy output. This method was applied to nuclear power-producing systems and their fuel cycles. Results were adapted to countries with various levels of industrialization and resources. With dynamic energy analysis different scenarios were investigated. For comparison purposes fossil-fuelled and solar power plants were analysed. The global results of static evaluation analysis were specifically modified according to the economic situations of countries with various levels of industrialization. The influence of energy imports upon energy analysis is also discussed. By dynamic energy analyses the cumulative energy requirements for specific power plant construction programmes have been compared with their total energy output. Investigations of this sort are extremely valuable not only for economic reasons, but especially for their usefulness in showing the advantages and disadvantages of a specific power programme with respect to its alternatives. Naturally the impact of these investigations on the fuel requirements is of importance, especially because of the frequently cited ''valuable cumulated fossil fuel savings''. (author)

  10. Increasing photovoltaic panel power through water cooling technique

    Directory of Open Access Journals (Sweden)

    Calebe Abrenhosa Matias

    2017-02-01

    Full Text Available This paper presents the development of a cooling apparatus using water in a commercial photovoltaic panel in order to analyze the increased efficiency through decreased operating temperature. The system enables the application of reuse water flow, at ambient temperature, on the front surface of PV panel and is composed of an inclined plane support, a perforated aluminum profile and a water gutter. A luminaire was specially developed to simulate the solar radiation over the module under test in a closed room, free from the influence of external climatic conditions, to carry out the repetition of the experiment in controlled situations. The panel was submitted to different rates of water flow. The best water flow rate was of 0.6 L/min and net energy of 77.41Wh. Gain of 22.69% compared to the panel without the cooling system.

  11. Numerical flow analysis of hydro power stations

    Science.gov (United States)

    Ostermann, Lars; Seidel, Christian

    2017-07-01

    For the hydraulic engineering and design of hydro power stations and their hydraulic optimisation, mainly experimental studies of the physical submodel or of the full model at the hydraulics laboratory are carried out. Partially, the flow analysis is done by means of computational fluid dynamics based on 2D and 3D methods and is a useful supplement to experimental studies. For the optimisation of hydro power stations, fast numerical methods would be appropriate to study the influence of a wide field of optimisation parameters and flow states. Among the 2D methods, especially the methods based on the shallow water equations are suitable for this field of application, since a lot of experience verified by in-situ measurements exists because of the widely used application of this method for the problems in hydraulic engineering. As necessary, a 3D model may supplement subsequently the optimisation of the hydro power station. The quality of the results of the 2D method for the optimisation of hydro power plants is investigated by means of the results of the optimisation of the hydraulic dividing pier compared to the results of the 3D flow analysis.

  12. INVESTIGATION WITH MODAL ANALYSIS OF EFFECTS OF HIGH PV PENETRATION ON POWER SYSTEM VOLTAGE STABILITY

    OpenAIRE

    YILDIRIM, Burak

    2017-01-01

    This paper shows the effects of high PVintegration on the power system voltage stability. PV power plant was appliedto the IEEE 30 bus test system. Modal analysis method is used to show theeffect of PV integration on power system voltage stability. The power rate ofsynchronous generator in the IEEE 30 bus system is increased to show the powersystem stability effect of high PV penetration and then the PV generation withthe same power rate is connected appropriate bus in power system. The modal...

  13. An Analysis of Chinese Communist National Power

    Science.gov (United States)

    1966-04-08

    Estimates of the annual growth rate vary from 1.6 to 2.5 percent. World population annual growth is estimated to be 2.1 percent a year.20 By 1980 China ...Politics Among Nations, p. 144. 240. Edmund Clubb, Twentieth Century China , p. 401. 13 Mao is well aware that population growth is a major...analysis of the power position of Communist China included an appraisal of her land, population , economy, armed forces, and political structure and

  14. Development of Standardized Power Electronic Components, Subsystems, and Systems for Increased Modularity and Scalability

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, S.; Pink, C.; Price, J.; Kroposki, B.; Kern, G.

    2007-11-01

    Power electronics devices hold substantial promise for making distributed energy applications more efficient and cost effective. This project is motivated towards developing and testing inverters that will allow distributed energy systems to provide ancillary services such as voltage and VAR regulation, and increased grid reliability by seamlessly transitioning between grid-tied and stand-alone operation modes. The objectives of this project are to identify system integration and optimization issues and technologies and to provide solutions through research, analysis, and testing of power electronic interfaces for distributed energy applications that are cost-competitive and have substantially faster response times than conventional technologies. In addition, the testing of power electronics interfaces will develop a technical basis for performance assessment for distributed energy systems, subsystems, and components that will finally create a foundation for standardized measurements and test procedures. The ultimate goal for this research is to advance the potential benefits of distributed energy to provide ancillary services, enhance power system reliability, and allow customer choice.

  15. Operating the Irish power system with increased levels of wind power

    DEFF Research Database (Denmark)

    Tuohy, A.; Denny, E.; Meibom, Peter

    2008-01-01

    This paper summarises some of the main impacts of large amounts of wind power installed in the island of Ireland. Using results from various studies performed on this system, it is shown that wind power will impact on all time frames, from seconds to daily planning of the system operation. Results...... from studies examining operation of the system with up to approximately 40% of electricity provided by wind show that some of the most important aspects to be considered include the type of wind turbine technology, the provision of reserve to accommodate wind forecasting error and the method used...

  16. Measurement and Analysis of Power in Hybrid System

    Directory of Open Access Journals (Sweden)

    Vartika Keshri

    2016-12-01

    Full Text Available Application with renewable energy  sources  such   as solar cell array, wind turbines, or fuel cells have increased significantly during the past decade. To obtain the clean energy, we are using the hybrid solar-wind power generation. Consumers prefer quality power from suppliers. The quality of power can be measured by using parameters such as voltage sag, harmonic and power factor.   To   obtain   quality   power   we   have different topologies. In our paper we present a new possible topology which improves power quality. This paper presents modeling analysis and design of a pulse width modulation voltage source inverter (PWM-VSI to be connected between sources, which supplies energy from a hybrid solar wind energy system to the ac grid. The objective of this paper is to show that, with an adequate control, the converter not only can transfer the dc from hybrid solar wind energy system, but also can improve the power factor and quality power of electrical system. Whenever a disturbance occurs on load side, this disturbance can be minimized using open loop and closed loop control systems.

  17. Dynamic Analysis of Power System Voltage Stability.

    Science.gov (United States)

    Gebreselassie, Assefa

    This thesis investigates the effects of loads and voltage regulators on the dynamic voltage stability of power systems. The analysis focuses on the interactions of machine flux dynamics with loads and voltage control devices. The results are based on eigenvalue analysis of the linearized models and time simulation of the nonlinear models, using models from the Power System Toolbox, a Matlab -based package for the simulation and small signal analysis of nonlinear power systems. The voltage stability analysis results are developed using a single machine single load system with typical machine and network parameters and the NPCC 10-machine system. Dynamic models for generators, exciters and loads are used. The generator is modeled with a pair of poles and one damper circuit in both the d-axis and the q-axis. Saturation effects are included in the model. The IEEE Type DC1 DC commutator exciter model is used for all the exciters. Five different types of loads: constant impedance, constant current, constant power, a first order induction motor model (slip model) and a third order induction motor model (slip-flux model) are considered. The modes of instability and the stability limits of the different representation of loads are examined for two different operating modes of the exciters. The first, when all the exciters are on automatic control and the second when some exciters are on manual control. Modal participation factors are used to determine the characteristics of the critical modes. The characteristics of the unstable modes are verified by performing time simulation of the nonlinear models. Oscillatory and non-oscillatory instabilities are experienced by load buses when all the exciters are on automatic control and some exciters are on manual control respectively, for loads which are predominantly constant power and induction motors. It is concluded that the mode of instability does not depend on the type of loads but on the operating condition of the exciters

  18. Dynein-deficient flagella respond to increased viscosity with contrasting changes in power and recovery strokes.

    Science.gov (United States)

    Wilson, Kate S; Gonzalez, Olivia; Dutcher, Susan K; Bayly, Philip V

    2015-09-01

    Changes in the flagellar waveform in response to increased viscosity were investigated in uniflagellate mutants of Chlamydomonas reinhardtii. We hypothesized that the waveforms of mutants lacking different dynein arms would change in different ways as viscosity was increased, and that these variations would illuminate the feedback pathways from force to dynein activity. Previous studies have investigated the effects of viscosity on cell body motion, propulsive force, and power in different mutants, but the effect on waveform has not yet been fully characterized. Beat frequency decreases with viscosity in wild-type uniflagellate (uni1) cells, and outer dynein arm deficient (oda2) mutants. In contrast, the inner dynein arm mutant ida1 (lacking I1/f) maintains beat frequency at high viscosity but alters its flagellar waveform more than either wild-type or oda2. The ida1 waveform is narrower than wild-type, primarily due to an abbreviated recovery stroke; this difference is amplified at high viscosity. The oda2 mutant in contrast, maintains a consistent waveform at high and low viscosity with a slightly longer power stroke than wild-type. Analysis of the delays and shear displacements between bends suggest that direct force feedback in the outer dynein arm system may initiate switching of dynein activity. In contrast, I1/f dynein appears to delay switching, most markedly at the initiation of the power stroke, possibly by controlling inter-doublet separation. © 2015 Wiley Periodicals, Inc.

  19. Analysis of the security during power system expansion planning

    Directory of Open Access Journals (Sweden)

    Osak Alexey

    2017-01-01

    Full Text Available Increasing the intelligent level of the EPS control systems, caused by the implementation of Smart technologies, changes the structure and the properties of EPS and increases the importance of system reliability analysis. System reliability analysis includes two components – for the balance and for the regime. On the one hand, there is a large number of studies to assess the reliability of the power system, which examines various aspects and methods of solving this problem. On the other hand, in Russia there is no generally accepted methodology with clear criteria that could be used for feasibility studies of various technical solutions taking into consideration system reliability aspects. In practice, the security analysis is limited by the calculations of power flows, static and dynamic stability for a number of forecast periods for the normal and repair circuits considering the most severe disturbances. The existing approach allows defining the requirements and adjusting emergency control systems, but does not allow evaluating and comparing solutions for power grid constructions. The authors propose a new method for power system reliability evaluation, which is suitable for planning development and operation of power systems. The method includes a general description of the algorithm which allows to compare various development scenarios, as well as to assess the reliability level of their implementation. In particular, the method allows to determine where it is needed only the relay protection and emergency control system development, and where it is necessary grid, protection and control development and reconstruction.

  20. Warm weather conditions moderated the increase of power consumption in Finland in 2000

    International Nuclear Information System (INIS)

    Kangas, H.

    2001-01-01

    Year 2000 was exceptionally warm in Finland. The amount of rainfalls in Northern Finland was larger than in 1999. This is shown clearly in the production of hydroelectric power. The wind conditions were also better, so the wind power generation doubled in 2000. The increase in power consumption in 2000 was only 1.7%. The power consumption rate was slightly over 79 TWh. The power consumption of household and agricultural sectors decreased by nearly 2% and in the public sector by 0.2%. The industrial power consumption increased by nearly 3%. Year 2000 was excellent for the industrial sector. The industrial production increased by 11%. The increment of power demand in heavy metal industry, chemical industry and forest industry was 5-7%. Power demand of process industry in 2000 exceeded 43.4 TWh, of which the share of building industry was more than 200 GWh. Process industry use about 55% of the total power consumption in Finland in 2000. The power demand of forest industry was 26.3 TWh, which is about 2% higher than in 1999. The corresponding figures for metal industry were 7.1 TWh and growth rate 3%. Chemical industry used in 2000 about 5.9 TWh of electric power. The growth rate was more that 4% higher in 2000 than in 1999. Power consumption of other industrial sectors in 2000 increased about 3% being now about 3.9 TWh. Hydroelectric power generation in 2000 was nearly 14.4 TWh, which is nearly 14.4 % higher than in 1999. The share of hydroelectric power generation of the total power consumption in Finland in 2000 was 18%. The wind power generation in 2000 was nearly 80 GWh, which are about 60% higher than in 1999. The number of wind power plants is 63, and the capacity of them 38 MW. The production of nuclear power in 2000 decreased by about 2% because of the longer and more thorough maintenance stoppages in the Loviisa 1 reactor. The utilisation rates of Finnish nuclear power plants in 2000 were high, Loviisa 1 by nearly 85%, Loviisa 2 by 91%, Olkiluoto 1 by 96

  1. Stochastic Modeling and Analysis of Power System with Renewable Generation

    DEFF Research Database (Denmark)

    Chen, Peiyuan

    . With the increasing number of wind turbines (WTs) connected to distribution systems, network operators are concerned about how such a stochastic generation affects power losses of the network. Furthermore, the operators need to estimate how much and when the stochastic generation can reduce the loading of substation...... be achieved through a probabilistic analysis that takes into account the stochastic behavior of wind power generation (WPG) and load demand. Such a probabilistic analysis may help network operators to cut down the cost associated with system planning. Thus, the objective of this thesis is to develop...... stochastic models of renewable generation and load demand for the optimal operation and planning of modern distribution systems through a probabilistic approach. On the basis of statistical data, stochastic models of WPG, load and combined heat and power (CHP) generation are developed. The stochastic wind...

  2. Energy analysis of nuclear power plants and their fuel cycle

    International Nuclear Information System (INIS)

    Held, C.; Moraw, G.; Schneeberger, M.; Szeless, A.

    1977-01-01

    Energy analysis has become an increasingly feasible and practical additional method for evaluating the engineering, economic and environmental aspects of power producing systems. Energy analysis compares total direct and indirect energy investment into construction and operation of power plants with their lifetime energy output. Statically we have applied this method to nuclear power producing sytems and their fuel cycles. Results were adapted to countries with various levels of industrialization and resources. With dynamic energy analysis different scenarios have been investigated. For comparison purposes fossil fueled and solar power plants have also been analyzed. By static evaluation it has been shown that for all types of power plants the energy investment for construction is shortly after plant startup being repaid by energy output. Static analyses of nuclear and fossil fuels have indicated values of fuel concentrations below which more energy is required for their utilization than can be obtained from the plants they fuel. In a further step these global results were specifically modified to the economic situations of countries with various levels of industrialization. Also the influence of energy imports upon energy analysis has been discussed. By dynamic energy analyses the cumulative energy requirements for specific power plant construction programs have been compared with their total energy output. Investigations of this sort are extremely valuable not only for economic reasons but especially for their usefulness in showing the advantages and disadvantages of a specific power program with respect to its alternatives. Naturally the impact of these investigations on the fuel requirements is of importance especially because of the today so often cited ''valuable cumulated fossil fuel savings''

  3. Sharing wind power forecasts in electricity markets: A numerical analysis

    International Nuclear Information System (INIS)

    Exizidis, Lazaros; Kazempour, S. Jalal; Pinson, Pierre; Greve, Zacharie de; Vallée, François

    2016-01-01

    Highlights: • Information sharing among different agents can be beneficial for electricity markets. • System cost decreases by sharing wind power forecasts between different agents. • Market power of wind producer may increase by sharing forecasts with market operator. • Extensive out-of-sample analysis is employed to draw reliable conclusions. - Abstract: In an electricity pool with significant share of wind power, all generators including conventional and wind power units are generally scheduled in a day-ahead market based on wind power forecasts. Then, a real-time market is cleared given the updated wind power forecast and fixed day-ahead decisions to adjust power imbalances. This sequential market-clearing process may cope with serious operational challenges such as severe power shortage in real-time due to erroneous wind power forecasts in day-ahead market. To overcome such situations, several solutions can be considered such as adding flexible resources to the system. In this paper, we address another potential solution based on information sharing in which market players share their own wind power forecasts with others in day-ahead market. This solution may improve the functioning of sequential market-clearing process through making more informed day-ahead schedules, which reduces the need for balancing resources in real-time operation. This paper numerically evaluates the potential value of sharing forecasts for the whole system in terms of system cost reduction. Besides, its impact on each market player’s profit is analyzed. The framework of this study is based on a stochastic two-stage market setup and complementarity modeling, which allows us to gain further insights into information sharing impacts.

  4. Advanced Wireless Power Transfer Vehicle and Infrastructure Analysis (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Gonder, J.; Brooker, A.; Burton, E.; Wang, J.; Konan, A.

    2014-06-01

    This presentation discusses current research at NREL on advanced wireless power transfer vehicle and infrastructure analysis. The potential benefits of E-roadway include more electrified driving miles from battery electric vehicles, plug-in hybrid electric vehicles, or even properly equipped hybrid electric vehicles (i.e., more electrified miles could be obtained from a given battery size, or electrified driving miles could be maintained while using smaller and less expensive batteries, thereby increasing cost competitiveness and potential market penetration). The system optimization aspect is key given the potential impact of this technology on the vehicles, the power grid and the road infrastructure.

  5. Advanced Power Plant Development and Analysis Methodologies

    Energy Technology Data Exchange (ETDEWEB)

    A.D. Rao; G.S. Samuelsen; F.L. Robson; B. Washom; S.G. Berenyi

    2006-06-30

    Under the sponsorship of the U.S. Department of Energy/National Energy Technology Laboratory, a multi-disciplinary team led by the Advanced Power and Energy Program of the University of California at Irvine is defining the system engineering issues associated with the integration of key components and subsystems into advanced power plant systems with goals of achieving high efficiency and minimized environmental impact while using fossil fuels. These power plant concepts include 'Zero Emission' power plants and the 'FutureGen' H2 co-production facilities. The study is broken down into three phases. Phase 1 of this study consisted of utilizing advanced technologies that are expected to be available in the 'Vision 21' time frame such as mega scale fuel cell based hybrids. Phase 2 includes current state-of-the-art technologies and those expected to be deployed in the nearer term such as advanced gas turbines and high temperature membranes for separating gas species and advanced gasifier concepts. Phase 3 includes identification of gas turbine based cycles and engine configurations suitable to coal-based gasification applications and the conceptualization of the balance of plant technology, heat integration, and the bottoming cycle for analysis in a future study. Also included in Phase 3 is the task of acquiring/providing turbo-machinery in order to gather turbo-charger performance data that may be used to verify simulation models as well as establishing system design constraints. The results of these various investigations will serve as a guide for the U. S. Department of Energy in identifying the research areas and technologies that warrant further support.

  6. A Hierarchical Visualization Analysis Model of Power Big Data

    Science.gov (United States)

    Li, Yongjie; Wang, Zheng; Hao, Yang

    2018-01-01

    Based on the conception of integrating VR scene and power big data analysis, a hierarchical visualization analysis model of power big data is proposed, in which levels are designed, targeting at different abstract modules like transaction, engine, computation, control and store. The regularly departed modules of power data storing, data mining and analysis, data visualization are integrated into one platform by this model. It provides a visual analysis solution for the power big data.

  7. Availability Performance Analysis of Thermal Power Plants

    Science.gov (United States)

    Bhangu, Navneet Singh; Singh, Rupinder; Pahuja, G. L.

    2018-03-01

    This case study presents the availability evaluation method of thermal power plants for conducting performance analysis in Indian environment. A generic availability model has been proposed for a maintained system (thermal plants) using reliability block diagrams and fault tree analysis. The availability indices have been evaluated under realistic working environment using inclusion exclusion principle. Four year failure database has been used to compute availability for different combinatory of plant capacity, that is, full working state, reduced capacity or failure state. Availability is found to be very less even at full rated capacity (440 MW) which is not acceptable especially in prevailing energy scenario. One of the probable reason for this may be the difference in the age/health of existing thermal power plants which requires special attention of each unit from case to case basis. The maintenance techniques being used are conventional (50 years old) and improper in context of the modern equipment, which further aggravate the problem of low availability. This study highlights procedure for finding critical plants/units/subsystems and helps in deciding preventive maintenance program.

  8. Power excursion analysis for high burnup cores

    Energy Technology Data Exchange (ETDEWEB)

    Diamond, D.J.; Neymotin, L.; Kohut, P. [Brookhaven National Lab., Upton, NY (United States)

    1996-02-01

    A study was undertaken of power excursions in high burnup cores. There were three objectives in this study. One was to identify boiling water reactor (BWR) and pressurized water reactor (PWR) transients in which there is significant energy deposition in the fuel. Another was to analyze the response of BWRs to the rod drop accident (RDA) and other transients in which there is a power excursion. The last objective was to investigate the sources of uncertainty in the RDA analysis. In a boiling water reactor, the events identified as having significant energy deposition in the fuel were a rod drop accident, a recirculation flow control failure, and the overpressure events; in a pressurized water reactor, they were a rod ejection accident and boron dilution events. The RDA analysis was done with RAMONA-4B, a computer code that models the space- dependent neutron kinetics throughout the core along with the thermal hydraulics in the core, vessel, and steamline. The results showed that the calculated maximum fuel enthalpy in high burnup fuel will be affected by core design, initial conditions, and modeling assumptions. The important uncertainties in each of these categories are discussed in the report.

  9. Human factor - an important reserve in increasing efficiency and safety of nuclear power plants

    International Nuclear Information System (INIS)

    Simunek, P.

    1982-01-01

    It is demonstrated that the relationship between man and technical equipment in a nuclear power plant should be studied using the systems analysis approach. The consistent use of ergonomic knowledge in nuclear power plants makes it possible with relatively small additional expenditure to achieve considerable economic effect. The establishment is therefore suggested of a workplace to coordinate the use of applied ergonomics in nuclear power plants. (Ha)

  10. Simulations of the design basis accident at conditions of power increase and the o transient of MSIV at overpressure conditions of the Laguna Verde Power Station

    International Nuclear Information System (INIS)

    Araiza M, E.; Nunez C, A.

    2001-01-01

    This document presents the analysis of the simulation of the loss of coolant accident at uprate power conditions, that is 2027 MWt (105% of the current rated power of 1931MWt). This power was reached allowing an increase in the turbine steam flow rate without changing the steam dome pressure value at its rated conditions (1020 psiaJ. There are also presented the results of the simulation of the main steam isolation va/ve transient at overpressure conditions 1065 psia and 1067 MWt), for Laguna Verde Nuclear Power Station. Both simulations were performed with the best estimate computer code TRA C BF1. The results obtained in the loss of coolant accident show that the emergency core coolant systems can recover the water level in the core before fuel temperature increases excessively, and that the peak pressure reached in the drywell is always below its design pressure. Therefore it is concluded that the integrity of the containment is not challenged during a loss of coolant accident at uprate power conditions.The analysis of the main steam isolation valve transients at overpressure conditions, and the analysis of the particular cases of the failure of one to six safety relief valves to open, show that the vessel peak pressures are below the design pressure and have no significant effect on vessel integrity. (Author)

  11. Power consumption analysis DBD plasma ozone generator

    Science.gov (United States)

    Nur, M.; Restiwijaya, M.; Muchlisin, Z.; Susan, I. A.; Arianto, F.; Widyanto, S. A.

    2016-11-01

    Studies on the consumption of energy by an ozone generator with various constructions electrodes of dielectric barrier discharge plasma (DBDP) reactor has been carried out. This research was done to get the configuration of the reactor, that is capable to produce high ozone concentrations with low energy consumption. BDBP reactors were constructed by spiral- cylindrical configuration, plasma ozone was generated by high voltage AC voltage up to 25 kV and maximum frequency of 23 kHz. The reactor consists of an active electrode in the form of a spiral-shaped with variation diameter Dc, and it was made by using copper wire with diameter Dw. In this research, we variated number of loops coil windings N as well as Dc and Dw. Ozone concentrations greater when the wire's diameter Dw and the diameter of the coil windings applied was greater. We found that impedance greater will minimize the concentration of ozone, in contrary to the greater capacitance will increase the concentration of ozone. The ozone concentrations increase with augmenting of power. Maximum power is effective at DBD reactor spiral-cylinder is on the Dc = 20 mm, Dw = 1.2 mm, and the number of coil windings N = 10 loops with the resulting concentration is greater than 20 ppm and it consumes energy of 177.60 watts

  12. PPICA, Power Plant Investment Cost Analysis

    International Nuclear Information System (INIS)

    Lefevre, J.C.

    2002-01-01

    1 - Description of program or function: This software package contains two modules: - CAPITAL1 calculates investment costs from overnight costs, based on the capital structure of the utility (debt/equity ratio), return and interest rates according to the type of securities involved, and a standard-shaped curve of capital outlays during construction of a power plant. - FCRATE1 calculates the year-by-year revenue requirements to cover the capital-related charges incurred by the new investment and their economic equivalent: the levelled fixed-charge rate and capital contribution to the levelled unit power generation cost per kWh. They are proposed as an alternative to the corresponding modules CAPITAL and FCRATE, included in the LPGC (Levelled Power Generation Cost) suite of codes developed by ORNL and US-DOE. They perform the same type of analysis and provide the same results. 2 - Methods: Results output from CAPITAL1, in terms of the initial investment at startup and the fraction thereof that is allowable for tax depreciation, can be transferred automatically as data input to FCRATE1. Other user-defined data are: the project life, the time horizon of the economic analysis (which does not necessarily coincide with the project life), the plant load factor (lifetime average), the tax rate applicable to utility's income, the tax depreciation scheme and the tax charge accounting method (normalised or flow- through). The results of CAPITAL1 and FCRATE1 are expressed both in current money and in constant money of a reference year. Inflation rate and escalation rate of construction expenditures during construction period, and of fixed charges during service life are defined by the user. The discount rate is set automatically by the programme, equal to the weighted average tax-adjusted cost of money. 3 - Restrictions on the complexity of the problem: CAPITAL1 and FCRATE1 are 'alternatives', not 'substitutes', to the corresponding programs CAPITAL and FCRATE of the LPGC

  13. 77 FR 20059 - License Amendment To Increase the Maximum Reactor Power Level, Florida Power & Light Company...

    Science.gov (United States)

    2012-04-03

    ... individuals (18 percent), respectively, living below the poverty level. Environmental Justice Impact Analysis... conditions in the vicinity of the PTN site. Environmental Justice Impacts The environmental justice impact... social impacts. Minority and low-income populations are subsets of the general public residing in the...

  14. Robust Steady State Analysis of the Power Grid

    OpenAIRE

    Pandey, Amritanshu; Jereminov, Marko; Wagner, Martin R.; Bromberg, David M.; Hug, Gabriela; Pileggi, Larry

    2018-01-01

    A robust methodology for obtaining the steady-state solution of the power grid is essential for reliable operation as well as planning of the future transmission and distribution grid. At present, disparate methods exist for steady-state analysis of the transmission (power flow) and distribution power grid (three-phase power flow). All existing alternating current (AC) power flow and three-phase power flow analyses formulate a non-linear problem that generally lacks the ability to ensure conv...

  15. Increased delta power and discrepancies in objective and subjective sleep measurements in borderline personality disorder.

    Science.gov (United States)

    Philipsen, Alexandra; Feige, Bernd; Al-Shajlawi, Anam; Schmahl, Christian; Bohus, Martin; Richter, Harald; Voderholzer, Ulrich; Lieb, Klaus; Riemann, Dieter

    2005-09-01

    Previous studies have shown depression-like sleep abnormalities in borderline personality disorder (BPD). However, findings in BPD are not unequivocal for REM dysregulation, as well as for a decrement of slow wave sleep and sleep continuity disturbances. Earlier findings in sleep EEG abnormalities in BPD may have been confounded by concomitant depressive symptoms. Twenty unmedicated female BPD patients without current comorbid major depression and 20 sex- and age-matched control subjects entered the study. Conventional polysomnographic parameters and for the first time sleep EEG spectral power analysis was performed on two sleep laboratory nights. Subjective sleep parameters were collected by sleep questionnaires in order to assess the relationship between objective and subjective sleep measurements. BPD patients showed a tendency for shortened REM latency and significantly decreased NonREM sleep (stage 2). Spectral EEG analysis showed increased delta power in total NREM sleep as well as in REM sleep in BPD patients. Subjective ratings documented drastically impaired sleep quality in BPD patients for the two weeks before the study and during the two laboratory nights. Not-depressed BPD patients only showed tendencies for depression-like REM sleep abnormalities. Surprisingly, BPD patients displayed higher levels of delta power in the sleep EEG in NREM sleep than healthy control subjects. There was a marked discrepancy between objective and subjective sleep measurements, which indicates an altered perception of sleep in BPD. The underlying psychological and neurobiological mechanisms of these alterations are still unclear and need to be clarified in future studies including interventions on a pharmacological and cognitive-behavioral level.

  16. Increasing power and life expectancy from the standpoint of the regulating authorities

    International Nuclear Information System (INIS)

    Naegelin, R.; Gilli, R.; Prantl, G.; Voumard, A.

    1990-01-01

    As far as the regulating authorities are concerned, there are no arguments against increasing the power of a nuclear power plant; but each case must be assessed individually, using all criteria in the light of the current state of knowledge. Nor are there any general reasons for limiting life expectancy at existing power stations to 20, 30 or even 40 years. Safety must be monitored constantly and operations cut back if necessary. 2 figs

  17. Statistical Analysis of the Impact of Wind Power on Market Quantities and Power Flows

    DEFF Research Database (Denmark)

    Pinson, Pierre; Jónsson, Tryggvi; Zugno, Marco

    2012-01-01

    In view of the increasing penetration of wind power in a number of power systems and markets worldwide, we discuss some of the impacts that wind energy may have on market quantities and cross-border power flows. These impacts are uncovered through statistical analyses of actual market and flow da...... of load and wind power forecasts on Danish and German electricity markets....

  18. Analysis of nuclear power plant construction costs

    International Nuclear Information System (INIS)

    1986-01-01

    The objective of this report is to present the results of a statistical analysis of nuclear power plant construction costs and lead-times (where lead-time is defined as the duration of the construction period), using a sample of units that entered construction during the 1966-1977 period. For more than a decade, analysts have been attempting to understand the reasons for the divergence between predicted and actual construction costs and lead-times. More importantly, it is rapidly being recognized that the future of the nuclear power industry rests precariously on an improvement in the cost and lead-time situation. Thus, it is important to study the historical information on completed plants, not only to understand what has occurred to also to improve the ability to evaluate the economics of future plants. This requires an examination of the factors that have affected both the realized costs and lead-times and the expectations about these factors that have been formed during the construction process. 5 figs., 22 tabs

  19. Analysis of nuclear power plant construction costs

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    The objective of this report is to present the results of a statistical analysis of nuclear power plant construction costs and lead-times (where lead-time is defined as the duration of the construction period), using a sample of units that entered construction during the 1966-1977 period. For more than a decade, analysts have been attempting to understand the reasons for the divergence between predicted and actual construction costs and lead-times. More importantly, it is rapidly being recognized that the future of the nuclear power industry rests precariously on an improvement in the cost and lead-time situation. Thus, it is important to study the historical information on completed plants, not only to understand what has occurred to also to improve the ability to evaluate the economics of future plants. This requires an examination of the factors that have affected both the realized costs and lead-times and the expectations about these factors that have been formed during the construction process. 5 figs., 22 tabs.

  20. Analysis of future nuclear power plants competitiveness with stochastic methods

    International Nuclear Information System (INIS)

    Feretic, D.; Tomsic, Z.

    2004-01-01

    To satisfy the increased demand it is necessary to build new electrical power plants, which could in an optimal way meet, the imposed acceptability criteria. The main criteria are potential to supply the required energy, to supply this energy with minimal (or at least acceptable) costs, to satisfy licensing requirements and be acceptable to public. The main competitors for unlimited electricity production in next few decades are fossil power plants (coal and gas) and nuclear power plants. New renewable power plants (solar, wind, biomass) are also important but due to limited energy supply potential and high costs can be only supplement to the main generating units. Large hydropower plans would be competitive under condition of existence of suitable sites for construction of such plants. The paper describes the application of a stochastic method for comparing economic parameters of future electrical power generating systems including conventional and nuclear power plants. The method is applied to establish competitive specific investment costs of future nuclear power plants when compared with combined cycle gas fired units combined with wind electricity generators using best estimated and optimistic input data. The bases for economic comparison of potential options are plant life time levelized electricity generating costs. The purpose is to assess the uncertainty of several key performance and cost of electricity produced in coal fired power plant, gas fired power plant and nuclear power plant developing probability distribution of levelized price of electricity from different Power Plants, cumulative probability of levelized price of electricity for each technology and probability distribution of cost difference between the technologies. The key parameters evaluated include: levelized electrical energy cost USD/kWh,, discount rate, interest rate for credit repayment, rate of expected increase of fuel cost, plant investment cost , fuel cost , constant annual

  1. Transmission expansion planning under increased uncertainties, towards efficient and sustainable power systems

    NARCIS (Netherlands)

    Ciupuliga, A.R.

    2013-01-01

    The ongoing liberalization process around the world has led to the emergence of energy markets, facilitating more international trade between countries making the best use of energy resources and optimizing overall power systems. Consequently, inter-area power exchanges have significantly increased

  2. Control of a hybrid HVDC link to increase inter-regional power transfer

    DEFF Research Database (Denmark)

    Kotb, Omar; Ghandhari, Mehrdad; Eriksson, Robert

    2016-01-01

    This paper examines the application of a hybrid HVDC link in a two area power system with the purpose of increasing the inter-regional power transfer. A hybrid HVDC system combines both LCCs and VSCs, and hence it is capable of combining the benefits of both converter technologies, such as reduced...

  3. Mixed-Methods Resistance Training Increases Power and Strength of Young and Older Men.

    Science.gov (United States)

    Newton, Robert U.; Hakkinen, Keijo; Hakkinen, Arja; McCormick, Matt; Volek, Jeff; Kraemer, William J.

    2002-01-01

    Examined the effects of a 10-week, mixed-methods resistance training program on young and older men. Although results confirmed some age-related reductions in muscle strength and power, the older men demonstrated similar capacity to the younger men for increases in muscle strength and power via an appropriate, periodized resistance training…

  4. Analysis of nuclear-power construction costs

    International Nuclear Information System (INIS)

    Jansma, G.L.; Borcherding, J.D.

    1988-01-01

    This paper discusses the use of regression analysis for estimating construction costs. The estimate is based on an historical data base and quantification of key factors considered external to project management. This technique is not intended as a replacement for detailed cost estimates but can provide information useful to the cost-estimating process and to top management interested in evaluating project management. The focus of this paper is the nuclear-power construction industry but the technique is applicable beyond this example. The approach and critical assumptions are also useful in a public-policy situation where utility commissions are evaluating construction in prudence reviews and making comparisons to other nuclear projects. 13 references, 2 figures

  5. Performance analysis of a microcontroller based slip power recovery ...

    African Journals Online (AJOL)

    Slip power recovery wound rotor induction motor drives are used in high power, limited speed range applications where control of slip power provides the variable speed drive system. In this paper, the steady state performance analysis of conventional slip power recovery scheme using static line commutated inverter in the ...

  6. Lower pressurization to increase BWR electric power under thermal hydraulic criteria

    International Nuclear Information System (INIS)

    Kataoka, Kazuyoshi; Chuman, Kazuto; Mizumachi, Wataru; Yoshioka, Ritsuo; Mori, Michitsugu; Horie, Akira; Machida, Yuzo

    1995-01-01

    Electric power output versus core size is one of the factors that determine the electricity generation costs of BWRs. The power output is roughly calculated from the thermal power of the BWR core and the thermal efficiency of the BWR turbine system. The thermal power is restricted by the reactor's thermal hydraulic criteria such as the maximum linear heat generation rate, the minimum critical power ratio, the pressure drop in the core and the feedwater temperature at the BWR inlet. The combination of a system pressure of approximately 5.5 MPa and a feedwater temperature of approximately 439 K offers the maximum electric power output for a BWR with 9 x 9 fuel bundles. The amount of electric power generated is about 9% more than that generated by a conventional BWR under the thermal hydraulic criteria. The electric power output increases as the system pressure and the feedwater temperature are decreased from the current design of 7.3 MPa and 488 K, respectively, because the increased critical power of the fuel bundles compensates for the lower thermal efficiency. (author)

  7. Dwell Mechanism for Increasing Free-Piston Stirling Engine Specific Power and Efficiency, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Proposed is a displacement dwell mechanism for increasing Stirling engine power output and efficiency. The dwell mechanism allows for deviations from a sinusoidal...

  8. Retrofitting a Geothermal Plant with Solar and Storage to Increase Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Guangdong [National Renewable Energy Laboratory (NREL), Golden, CO (United States); McTigue, Joshua Dominic P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Turchi, Craig S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Castro, Jose [Coso Operating Co.; Mungas, Greg [Hyperlight Energy; Kramer, Nick [Hyperlight Energy; King, John [Hyperlight Energy

    2017-10-04

    Solar hybridization using concentrating solar power (CSP) can be an effective approach to augment the power generation and power cycle efficiency of a geothermal power plant with a declining resource. Thermal storage can further increase the dispatchability of a geothermal/solar hybrid system, which is particularly valued for a national grid with high renewable penetration. In this paper, a hybrid plant design with thermal storage is proposed based on the requirements of the Coso geothermal field in China Lake, California. The objective is to increase the power production by 4 MWe. In this system, a portion of the injection brine is recirculated through a heat exchanger with the solar heat transfer fluid, before being mixed with the production well brine. In the solar heating loop the brine should be heated to at least 155 degrees C to increase the net power. The solar field and storage were sized based on solar data for China Lake. Thermal storage is used to store excess power at the high-solar-irradiation hours and generate additional power during the evenings. The solar field size, the type and capacity of thermal storage and the operating temperatures are critical factors in determining the most economic hybrid system. Further investigations are required to optimize the hybrid system and evaluate its economic feasibility.

  9. Power Analysis of Traction Transformer under Non-Sinusoidal Conditions

    Directory of Open Access Journals (Sweden)

    Jaromir Kijonka

    2004-01-01

    Full Text Available Article deals with power analysis of traction transformer 100/27 kV, Sn= 10MVA under non-sinusoidal conditions. The power analysis is evaluated by means of IEEE Trial Use Standard Definitions of the Electric Power Quantities under Non-Sinusoidal Conditions, Document Number: IEEE 1459-2000.

  10. Measurement Error and Equating Error in Power Analysis

    Science.gov (United States)

    Phillips, Gary W.; Jiang, Tao

    2016-01-01

    Power analysis is a fundamental prerequisite for conducting scientific research. Without power analysis the researcher has no way of knowing whether the sample size is large enough to detect the effect he or she is looking for. This paper demonstrates how psychometric factors such as measurement error and equating error affect the power of…

  11. Proprioceptive neuromuscular facilitation increases alpha absolute power in the dorsolateral prefrontal cortex and superior parietal cortex.

    Science.gov (United States)

    Lial, Lysnara; Moreira, Rayele; Correia, Luan; Andrade, Alzira; Pereira, Ane Caroline; Lira, Ricardo; Figueiredo, Rogério; Silva-Júnior, Fernando; Orsini, Marco; Ribeiro, Pedro; Velasques, Bruna; Cagy, Maurício; Teixeira, Silmar; Bastos, Victor Hugo

    2017-09-01

    The physiotherapist's clinical practice includes proprioceptive neuromuscular facilitation (PNF), which is a treatment concept that accelerates the response of neuromuscular mechanisms through spiral and diagonal movements. The adaptations that occur in the nervous system following PNF are still poorly described in the literature. Thus, this study had a goal to investigate the electrophysiological changes in the fronto-parietal circuit during PNF and movement in sagittal and diagonal patterns. This study included 30 female participants, who were divided into three groups (control, PNF, and flexion groups). Electroencephalogram measurements were determined before and after tasks were performed by each group. For the statistical analysis, a two-way ANOVA was performed for the factors group and time. Interactions between the two factors were investigated using a one-way ANOVA. A value of p < 0.004 was considered significant. The results showed an increase in alpha absolute power in the left dorsolateral prefrontal cortex and upper left parietal cortex of the PNF group, suggesting these areas work together to execute a motor action. The PNF group showed a greater alpha absolute power compared with the other groups, indicating a specific cortical demand for planning and attention, reinforcing its use for the rehabilitation of individuals.

  12. Electric power systems analysis and control

    CERN Document Server

    Saccomanno, Fabio

    2003-01-01

    "Highly relevant and timely in scope, the book is essential reading for anyone associated with electric power systems, including students and teachers of power engineering courses, professionals in the industry, consultants, and researchers."--Jacket.

  13. Atucha I nuclear power plant transients analysis

    International Nuclear Information System (INIS)

    Castano, J.; Schivo, M.

    1987-01-01

    A program for the transients simulation thermohydraulic calculation without loss of coolant (KWU-ENACE development) to evaluate Atucha I nuclear power plant behaviour is used. The program includes systems simulation and nuclear power plants control bonds with real parameters. The calculation results show a good agreement with the output 'protocol' of various transients of the nuclear power plant, keeping the error, in general, lesser than ± 10% from the variation of the nuclear power plant's state variables. (Author)

  14. Complex Evaluation of Light Sources in Case of Electric Power Cost Increase

    Directory of Open Access Journals (Sweden)

    Y. N. Kolesnik

    2008-01-01

    Full Text Available The paper gives complex evaluation of efficiency of incandescent lamps, luminescent and light-emitting-diode (LED light sources in case of electric power price increase. On the basis of experimental table lamp electric power indices of light-emitting-diode (LED light sources with equivalent luminous flux have been determined. Dependences of main indices of economic efficiency of various light sources on their operational regimes have been obtained and rate of influence on these indices of electric power price increase have been determined. Economically justified variants and conditions for application of various light sources have been substantiated.

  15. Transient analysis models for nuclear power plants

    International Nuclear Information System (INIS)

    Agapito, J.R.

    1981-01-01

    The modelling used for the simulation of the Angra-1 start-up reactor tests, using the RETRAN computer code is presented. Three tests are simulated: a)nuclear power plant trip from 100% of power; b)great power excursions tests and c)'load swing' tests.(E.G.) [pt

  16. Analysis and study on core power capability with margin method

    International Nuclear Information System (INIS)

    Liu Tongxian; Wu Lei; Yu Yingrui; Zhou Jinman

    2015-01-01

    Core power capability analysis focuses on the power distribution control of reactor within the given mode of operation, for the purpose of defining the allowed normal operating space so that Condition Ⅰ maneuvering flexibility is maintained and Condition Ⅱ occurrences are adequately protected by the reactor protection system. For the traditional core power capability analysis methods, such as synthesis method or advanced three dimension method, usually calculate the key safety parameters of the power distribution, and then verify that these parameters meet the design criteria. For PWR with on-line power distribution monitoring system, core power capability analysis calculates the most power level which just meets the design criteria. On the base of 3D FAC method of Westinghouse, the calculation model of core power capability analysis with margin method is introduced to provide reference for engineers. The core power capability analysis of specific burnup of Sanmen NPP is performed with the margin method. The results demonstrate the rationality of the margin method. The calculation model of the margin method not only helps engineers to master the core power capability analysis for AP1000, but also provides reference for engineers for core power capability analysis of other PWR with on-line power distribution monitoring system. (authors)

  17. Advances in power system modelling, control and stability analysis

    CERN Document Server

    Milano, Federico

    2016-01-01

    Advances in Power System Modelling, Control and Stability Analysis captures the variety of new methodologies and technologies that are changing the way modern electric power systems are modelled, simulated and operated.

  18. Power-to-heat in adiabatic compressed air energy storage power plants for cost reduction and increased flexibility

    Science.gov (United States)

    Dreißigacker, Volker

    2018-04-01

    The development of new technologies for large-scale electricity storage is a key element in future flexible electricity transmission systems. Electricity storage in adiabatic compressed air energy storage (A-CAES) power plants offers the prospect of making a substantial contribution to reach this goal. This concept allows efficient, local zero-emission electricity storage on the basis of compressed air in underground caverns. The compression and expansion of air in turbomachinery help to balance power generation peaks that are not demand-driven on the one hand and consumption-induced load peaks on the other. For further improvements in cost efficiencies and flexibility, system modifications are necessary. Therefore, a novel concept regarding the integration of an electrical heating component is investigated. This modification allows increased power plant flexibilities and decreasing component sizes due to the generated high temperature heat with simultaneously decreasing total round trip efficiencies. For an exemplarily A-CAES case simulation studies regarding the electrical heating power and thermal energy storage sizes were conducted to identify the potentials in cost reduction of the central power plant components and the loss in round trip efficiency.

  19. Power-to-heat in adiabatic compressed air energy storage power plants for cost reduction and increased flexibility

    Science.gov (United States)

    Dreißigacker, Volker

    2017-10-01

    The development of new technologies for large-scale electricity storage is a key element in future flexible electricity transmission systems. Electricity storage in adiabatic compressed air energy storage (A-CAES) power plants offers the prospect of making a substantial contribution to reach this goal. This concept allows efficient, local zero-emission electricity storage on the basis of compressed air in underground caverns. The compression and expansion of air in turbomachinery help to balance power generation peaks that are not demand-driven on the one hand and consumption-induced load peaks on the other. For further improvements in cost efficiencies and flexibility, system modifications are necessary. Therefore, a novel concept regarding the integration of an electrical heating component is investigated. This modification allows increased power plant flexibilities and decreasing component sizes due to the generated high temperature heat with simultaneously decreasing total round trip efficiencies. For an exemplarily A-CAES case simulation studies regarding the electrical heating power and thermal energy storage sizes were conducted to identify the potentials in cost reduction of the central power plant components and the loss in round trip efficiency.

  20. Fault analysis of multichannel spacecraft power systems

    Science.gov (United States)

    Dugal-Whitehead, Norma R.; Lollar, Louis F.

    1990-01-01

    The NASA Marshall Space Flight Center proposes to implement computer-controlled fault injection into an electrical power system breadboard to study the reactions of the various control elements of this breadboard. Elements under study include the remote power controllers, the algorithms in the control computers, and the artificially intelligent control programs resident in this breadboard. To this end, a study of electrical power system faults is being performed to yield a list of the most common power system faults. The results of this study will be applied to a multichannel high-voltage DC spacecraft power system called the large autonomous spacecraft electrical power system (LASEPS) breadboard. The results of the power system fault study and the planned implementation of these faults into the LASEPS breadboard are described.

  1. Yoga Poses Increase Subjective Energy and State Self-Esteem in Comparison to 'Power Poses'.

    Science.gov (United States)

    Golec de Zavala, Agnieszka; Lantos, Dorottya; Bowden, Deborah

    2017-01-01

    Research on beneficial consequences of yoga focuses on the effects of yogic breathing and meditation. Less is known about the psychological effects of performing yoga postures. The present study investigated the effects of yoga poses on subjective sense of energy and self-esteem. The effects of yoga postures were compared to the effects of 'power poses,' which arguably increase the sense of power and self-confidence due to their association with interpersonal dominance (Carney et al., 2010). The study tested the novel prediction that yoga poses, which are not associated with interpersonal dominance but increase bodily energy, would increase the subjective feeling of energy and therefore increase self-esteem compared to 'high power' and 'low power' poses. A two factorial, between participants design was employed. Participants performed either two standing yoga poses with open front of the body ( n = 19), two standing yoga poses with covered front of the body ( n = 22), two expansive, high power poses ( n = 21), or two constrictive, low power poses ( n = 20) for 1-min each. The results showed that yoga poses in comparison to 'power poses' increased self-esteem. This effect was mediated by an increased subjective sense of energy and was observed when baseline trait self-esteem was controlled for. These results suggest that the effects of performing open, expansive body postures may be driven by processes other than the poses' association with interpersonal power and dominance. This study demonstrates that positive effects of yoga practice can occur after performing yoga poses for only 2 min.

  2. Balance of the LVC plant with increase in 15 % of power

    International Nuclear Information System (INIS)

    Ortiz, J.J.; Hernandez, J.L.; Perusquia, R.; Castillo, A.; Montes, J.L.

    2005-01-01

    One of the tendencies in many power reactors has been to modify some operation conditions, in order to increasing the electricity generation. The Laguna Verde Nuclear power plant (CNLV) it has not been the exception and in the recent past an increment of 5% was made in the original nominal thermal power. In the face of the possibility of carrying out more modifications, a study was made in the one that one simulates an eventual increment of the power of the reactor in 15% of the original value. With this increment one carries out the balance of the plant and the thermodynamic properties were determined. With this purpose it was developed a computer tool to calculate the thermodynamic properties of the plant in several points of the power cycle, as well as to carry out energy and mass balances to determine the flows in the different extractions of steam of the turbines. The program is compared with the results to 100% and 105% of increase of power obtaining good results, for what it is concluded that the extrapolation to 115% of power increase is acceptable. (Author)

  3. Station Blackout Analysis of HTGR-Type Experimental Power Reactor

    Science.gov (United States)

    Syarip; Zuhdi, Aliq; Falah, Sabilul

    2018-01-01

    The National Nuclear Energy Agency of Indonesia has decided to build an experimental power reactor of high-temperature gas-cooled reactor (HTGR) type located at Puspiptek Complex. The purpose of this project is to demonstrate a small modular nuclear power plant that can be operated safely. One of the reactor safety characteristics is the reliability of the reactor to the station blackout (SBO) event. The event was observed due to relatively high disturbance frequency of electricity network in Indonesia. The PCTRAN-HTR functional simulator code was used to observe fuel and coolant temperature, and coolant pressure during the SBO event. The reactor simulated at 10 MW for 7200 s then the SBO occurred for 1-3 minutes. The analysis result shows that the reactor power decreases automatically as the temperature increase during SBO accident without operator’s active action. The fuel temperature increased by 36.57 °C every minute during SBO and the power decreased by 0.069 MW every °C fuel temperature rise at the condition of anticipated transient without reactor scram. Whilst, the maximum coolant (helium) temperature and pressure are 1004 °C and 9.2 MPa respectively. The maximum fuel temperature is 1282 °C, this value still far below the fuel temperature limiting condition i.e. 1600 °C, its mean that the HTGR has a very good inherent safety system.

  4. Power System Transient Stability Analysis through a Homotopy Analysis Method

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shaobu; Du, Pengwei; Zhou, Ning

    2014-04-01

    As an important function of energy management systems (EMSs), online contingency analysis plays an important role in providing power system security warnings of instability. At present, N-1 contingency analysis still relies on time-consuming numerical integration. To save computational cost, the paper proposes a quasi-analytical method to evaluate transient stability through time domain periodic solutions’ frequency sensitivities against initial values. First, dynamic systems described in classical models are modified into damping free systems whose solutions are either periodic or expanded (non-convergent). Second, because the sensitivities experience sharp changes when periodic solutions vanish and turn into expanded solutions, transient stability is assessed using the sensitivity. Third, homotopy analysis is introduced to extract frequency information and evaluate the sensitivities only from initial values so that time consuming numerical integration is avoided. Finally, a simple case is presented to demonstrate application of the proposed method, and simulation results show that the proposed method is promising.

  5. An analysis of nuclear power plant operating costs

    International Nuclear Information System (INIS)

    1988-01-01

    This report presents the results of a statistical analysis of nonfuel operating costs for nuclear power plants. Most studies of the economic costs of nuclear power have focused on the rapid escalation in the cost of constructing a nuclear power plant. The present analysis found that there has also been substantial escalation in real (inflation-adjusted) nonfuel operating costs. It is important to determine the factors contributing to the escalation in operating costs, not only to understand what has occurred but also to gain insights about future trends in operating costs. There are two types of nonfuel operating costs. The first is routine operating and maintenance expenditures (O and M costs), and the second is large postoperational capital expenditures, or what is typically called ''capital additions.'' O and M costs consist mainly of expenditures on labor, and according to one recently completed study, the majoriy of employees at a nuclear power plant perform maintenance activities. It is generally thought that capital additions costs consist of large maintenance expenditures needed to keep the plants operational, and to make plant modifications (backfits) required by the Nuclear Regulatory Commission (NRC). Many discussions of nuclear power plant operating costs have not considered these capital additions costs, and a major finding of the present study is that these costs are substantial. The objective of this study was to determine why nonfuel operating costs have increased over the past decade. The statistical analysis examined a number of factors that have influenced the escalation in real nonfuel operating costs and these are discussed in this report. 4 figs, 19 tabs

  6. Performance Prediction of Wind Power Turbine by CAD Analysis

    International Nuclear Information System (INIS)

    Kim, Jongho; Kim, Jongbong; Oh, Younglok

    2013-01-01

    The performance of a vertical-type wind power generator system was predicted by CAD analysis. In the analysis, the reaction torque was calculated for a given rotational speed of the blades. The blade torque of a wind power system was obtained for various rotational speeds, and the generation power was calculated using the obtained torque and the rotational speed. The optimum generator specification, therefore, could be decided using the relationship between the generated power and the rotational speeds. The effects of the number of blades and blade shapes on the generation power were also investigated. Finally, the analysis results were compared with the experimental results

  7. Sensitivity analysis of hybrid power systems using Power Pinch Analysis considering Feed-in Tariff

    International Nuclear Information System (INIS)

    Mohammad Rozali, Nor Erniza; Wan Alwi, Sharifah Rafidah; Manan, Zainuddin Abdul; Klemeš, Jiří Jaromír

    2016-01-01

    Feed-in Tariff (FiT) has been one of the most effective policies in accelerating the development of renewable energy (RE) projects. The amount of RE electricity in the FiT purchase agreement is an important decision that has to be made by the RE project developers. They have to consider various crucial factors associated with RE system operation as well as its stochastic nature. The presented work aims to assess the sensitivity and profitability of a hybrid power system (HPS) in cases of RE system failure or shutdown. The amount of RE electricity for the FiT purchase agreement in various scenarios was determined using a novel tool called On-Grid Problem Table based on the Power Pinch Analysis (PoPA). A sensitivity table has also been introduced to assist planners to evaluate the effects of the RE system's failure on the profitability of the HPS. This table offers insights on the variance of the RE electricity. The sensitivity analysis of various possible scenarios shows that the RE projects can still provide financial benefits via the FiT, despite the losses incurred from the penalty levied. - Highlights: • A Power Pinch Analysis (PoPA) tool to assess the economics of an HPS with FiT. • The new On-Grid Problem Table for targeting the available RE electricity for FiT sale. • A sensitivity table showing the effect of RE electricity changes on the HPS profitability.

  8. Analysis of nuclear power plant component failures

    Energy Technology Data Exchange (ETDEWEB)

    1984-01-01

    Items are shown that have caused 90% of the nuclear unit outages and/or deratings between 1971 and 1980 and the magnitude of the problem indicated by an estimate of power replacement cost when the units are out of service or derated. The funding EPRI has provided on these specific items for R and D and technology transfer in the past and the funding planned in the future (1982 to 1986) are shown. EPRI's R and D may help the utilities on only a small part of their nuclear unit outage problems. For example, refueling is the major cause for nuclear unit outages or deratings and the steam turbine is the second major cause for nuclear unit outages; however, these two items have been ranked fairly low on the EPRI priority list for R and D funding. Other items such as nuclear safety (NRC requirements), reactor general, reactor and safety valves and piping, and reactor fuel appear to be receiving more priority than is necessary as determined by analysis of nuclear unit outage causes.

  9. Analysis and determination of power purchase price

    International Nuclear Information System (INIS)

    Zhang, C.; Glen, C.; Jenden, K.

    1995-01-01

    Any agency proposing to connect a windfarm to the power grid must first arrange a power purchase contract involving a power purchase price (PPP). This paper reviews methods of determining the initial PPP and of establishing the mechanism for subsequent annual PPP reviews, both as two separate functions and as combined elements in an optimisation procedure. Various strategies for dealing with the PPP and its annual review are discussed. (Author)

  10. Geometrical Methods for Power Network Analysis

    CERN Document Server

    Bellucci, Stefano; Gupta, Neeraj

    2013-01-01

    This book is a short introduction to power system planning and operation using advanced geometrical methods. The approach is based on well-known insights and techniques developed in theoretical physics in the context of Riemannian manifolds. The proof of principle and robustness of this approach is examined in the context of the IEEE 5 bus system. This work addresses applied mathematicians, theoretical physicists and power engineers interested in novel mathematical approaches to power network theory.

  11. Hydropower: a vital asset in a power system with increased need for flexibility and firm capacity

    International Nuclear Information System (INIS)

    Weisrock, Ghislain

    2016-02-01

    In a power system with increased need for flexibility, wind and solar power are characterised by considerable volatility across different scales and their output cannot be predicted with certainty. In order to deal with the resulting variations and forecast errors, system operators as well as electricity markets will need to have access to increasing volumes of flexibility as the penetration of wind and solar power grows. Due to their flexibility and size, hydropower plants are perfectly suited for supplying these capabilities to current and future electricity markets and power systems. Storage as well as pump storage plants can be quickly started within a few minutes and adjust their output within seconds. Consequently, hydropower plants are able to follow even major variations in real time. (author)

  12. Power flow analysis for DC voltage droop controlled DC microgrids

    DEFF Research Database (Denmark)

    Li, Chendan; Chaudhary, Sanjay; Dragicevic, Tomislav

    2014-01-01

    This paper proposes a new algorithm for power flow analysis in droop controlled DC microgrids. By considering the droop control in the power flow analysis for the DC microgrid, when compared with traditional methods, more accurate analysis results can be obtained. The algorithm verification...

  13. Disintegration of power grid as part of the task of increasing functionality of electric system

    Directory of Open Access Journals (Sweden)

    Mukatov Bekzhan

    2017-01-01

    operation is inevitable with reduced reliability or, otherwise, with incomplete functionality where functionality is the set of functions provided by the power system and the quality of their performance. With the mass input of distributed small generation in grids of almost all voltage classes it is necessary to solve the problem of ensuring stability in previously passive distribution networks. The traditional approach based on the “struggle” to maintain synchronism between power plants in the distribution networks is associated with a number of difficulties, which causes to apply another approach to control modes in distribution networks. Complication of the power grid, automatic devices, increase in possible variations of modes, and tendency to maximize the use of production assets lead to an increase in the complexity of tasks solved by dispatch centers. In this regard, it is important to note that availability of cascade failures in power systems speaks of the urgency of the task of ensuring the survivability of energy supply systems both globally and locally. The paper shows how disintegration of the power grid can solve the task of ensuring the functionality of traditional power systems and help to create favorable conditions for distributed small generation integration into the integrated electric power system.

  14. Power Consumption Analysis of Electrical Installations at Healthcare Facility

    Directory of Open Access Journals (Sweden)

    Emmanuel Guillen-Garcia

    2017-01-01

    Full Text Available This paper presents a methodology for power consumption estimation considering harmonic and interharmonic content and then it is compared to the power consumption estimation commonly done by commercial equipment based on the fundamental frequency, and how they can underestimate the power consumption considering power quality disturbances (PQD. For this purpose, data of electrical activity at the electrical distribution boards in a healthcare facility is acquired for a long time period with proprietary equipment. An analysis in the acquired current and voltage signals is done, in order to compare the power consumption centered in the fundamental frequency with the generalized definition of power consumption. The results obtained from the comparison in the power consumption estimation show differences between 4% and 10% of underestimated power consumption. Thus, it is demonstrated that the presence of harmonic and interharmonic content provokes a significant underestimation of power consumption using only the power consumption centered at the fundamental frequency.

  15. Operating health analysis of electric power systems

    Science.gov (United States)

    Fotuhi-Firuzabad, Mahmud

    The required level of operating reserve to be maintained by an electric power system can be determined using both deterministic and probabilistic techniques. Despite the obvious disadvantages of deterministic approaches there is still considerable reluctance to apply probabilistic techniques due to the difficulty of interpreting a single numerical risk index and the lack of sufficient information provided by a single index. A practical way to overcome difficulties is to embed deterministic considerations in the probabilistic indices in order to monitor the system well-being. The system well-being can be designated as healthy, marginal and at risk. The concept of system well-being is examined and extended in this thesis to cover the overall area of operating reserve assessment. Operating reserve evaluation involves the two distinctly different aspects of unit commitment and the dispatch of the committed units. Unit commitment health analysis involves the determination of which unit should be committed to satisfy the operating criteria. The concepts developed for unit commitment health, margin and risk are extended in this thesis to evaluate the response well-being of a generating system. A procedure is presented to determine the optimum dispatch of the committed units to satisfy the response criteria. The impact on the response wellbeing being of variations in the margin time, required regulating margin and load forecast uncertainty are illustrated. The effects on the response well-being of rapid start units, interruptible loads and postponable outages are also illustrated. System well-being is, in general, greatly improved by interconnection with other power systems. The well-being concepts are extended to evaluate the spinning reserve requirements in interconnected systems. The interconnected system unit commitment problem is decomposed into two subproblems in which unit scheduling is performed in each isolated system followed by interconnected system evaluation

  16. A coherency-based method to increase dynamic security in power systems

    Energy Technology Data Exchange (ETDEWEB)

    De Tuglie, E. [Dipartimento di Ingegneria dell' Ambiente e per lo Sviluppo Sostenibile - DIASS, Politecnico di Bari, Viale del Turismo 8, 74100 Taranto (Italy); Iannone, S.M.; Torelli, F. [Dipartimento di Elettrotecnica ed Elettronica - DEE, Politecnico di Bari, Via Re David 200, 70125 Bari (Italy)

    2008-08-15

    Dynamic security analysis is the evaluation of the ability of a system to withstand contingencies by surviving transient conditions to acceptable steady-state operative states. When potential instability due to contingency is detected, preventive action may be desired to improve the system security. This is very important in the on-line operation of a power system, especially when the system is stability-limited. The method proposed in this paper is based on the idea that increasing coherency between generators in the transient behaviour following a system perturbation gives rise to a more stable system. In this paper, we suggest the use of the ''input-output feedback-linearization'' with a reference trajectory obtained using a system dynamic equivalent based on the centre of inertia. To quantify coherency levels a new coherency indicator has been assumed for the given reference trajectory. The result is an increasing level in coherency, critical clearing time and system stability. The method is tested on the IEEE 30 bus test system. (author)

  17. Increasing power generation for scaling up single-chamber air cathode microbial fuel cells

    KAUST Repository

    Cheng, Shaoan

    2011-03-01

    Scaling up microbial fuel cells (MFCs) requires a better understanding the importance of the different factors such as electrode surface area and reactor geometry relative to solution conditions such as conductivity and substrate concentration. It is shown here that the substrate concentration has significant effect on anode but not cathode performance, while the solution conductivity has a significant effect on the cathode but not the anode. The cathode surface area is always important for increasing power. Doubling the cathode size can increase power by 62% with domestic wastewater, but doubling the anode size increases power by 12%. Volumetric power density was shown to be a linear function of cathode specific surface area (ratio of cathode surface area to reactor volume), but the impact of cathode size on power generation depended on the substrate strength (COD) and conductivity. These results demonstrate the cathode specific surface area is the most critical factor for scaling-up MFCs to obtain high power densities. © 2010 Elsevier Ltd.

  18. Laguna Verde after the extended power increase; Laguna Verde despues del aumento de potencia extendido

    Energy Technology Data Exchange (ETDEWEB)

    Herrera C, M. N.; Castaneda G, M. A.; Cardenas J, J. B.; Garcia de la C, F. M., E-mail: mitzi.herrera@cfe.gob.mx [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Carretera Cardel-Nautla Km 42.5, Alto Lucero, Veracruz (Mexico)

    2012-10-15

    The project of extended power increase that was implemented in both units of the nuclear power plant of Laguna Verde beginning with the stage feasibility evaluation in nuclear side of the facilities, that is to say the affectation of the power increase in the equipment s, systems and components of the nuclear power plant; besides the feasibility evaluation a study cost-benefit for the rehabilitated and modernization of the equipment s, systems and components of Plant Balance was realized. Once considered technical and economically feasible the project began the engineering evaluations required to carry out the licensing of the new operation conditions, as well as beginning to the elaboration of the technical specifications purchase of the equipment s, systems and components of the Plant Balance. While on one hand was carried out the administration of the licensing of the extended power increase for other was carried out the necessary engineering to make the physical changes in the conventional side of the nuclear power plant. Once concluded the constructive stage beginning the final stage of the project, the starting-up tests, operation and performance of the Units under the new operation conditions. This work describes this last stage that contains the technical base, the realized tests and the obtained results. (Author)

  19. Competitive analysis of small hydroelectric power plants

    International Nuclear Information System (INIS)

    Assad, L.S.; Placido, R.

    1990-01-01

    The agreement between CPFL/UNICAMP/EFEI for developing energetic planning of Small Hydroelectric Power Plants construction is described. Some notions for showing the more economic alternative between decide by Small Hydroelectric Power Plants construction and continue supply the market by inter ligated system generation are shown in this stage of the agreement. (author)

  20. Power spectrum analysis for optical tweezers

    DEFF Research Database (Denmark)

    Berg-Sørensen, K.; Flyvbjerg, H.

    2004-01-01

    The force exerted by an optical trap on a dielectric bead in a fluid is often found by fitting a Lorentzian to the power spectrum of Brownian motion of the bead in the trap. We present explicit functions of the experimental power spectrum that give the values of the parameters fitted, including...... error bars and correlations, for the best such chi(2) fit in a given frequency range. We use these functions to determine the information content of various parts of the power spectrum, and find, at odds with lore, much information at relatively high frequencies. Applying the method to real data, we...... obtain perfect fits and calibrate tweezers with less than 1% error when the trapping force is not too strong. Relatively strong traps have power spectra that cannot be fitted properly with any Lorentzian, we find. This underscores the need for better understanding of the power spectrum than...

  1. Using pre-existing microarray datasets to increase experimental power: application to insulin resistance.

    Directory of Open Access Journals (Sweden)

    Bernie J Daigle

    2010-03-01

    Full Text Available Although they have become a widely used experimental technique for identifying differentially expressed (DE genes, DNA microarrays are notorious for generating noisy data. A common strategy for mitigating the effects of noise is to perform many experimental replicates. This approach is often costly and sometimes impossible given limited resources; thus, analytical methods are needed which increase accuracy at no additional cost. One inexpensive source of microarray replicates comes from prior work: to date, data from hundreds of thousands of microarray experiments are in the public domain. Although these data assay a wide range of conditions, they cannot be used directly to inform any particular experiment and are thus ignored by most DE gene methods. We present the SVD Augmented Gene expression Analysis Tool (SAGAT, a mathematically principled, data-driven approach for identifying DE genes. SAGAT increases the power of a microarray experiment by using observed coexpression relationships from publicly available microarray datasets to reduce uncertainty in individual genes' expression measurements. We tested the method on three well-replicated human microarray datasets and demonstrate that use of SAGAT increased effective sample sizes by as many as 2.72 arrays. We applied SAGAT to unpublished data from a microarray study investigating transcriptional responses to insulin resistance, resulting in a 50% increase in the number of significant genes detected. We evaluated 11 (58% of these genes experimentally using qPCR, confirming the directions of expression change for all 11 and statistical significance for three. Use of SAGAT revealed coherent biological changes in three pathways: inflammation, differentiation, and fatty acid synthesis, furthering our molecular understanding of a type 2 diabetes risk factor. We envision SAGAT as a means to maximize the potential for biological discovery from subtle transcriptional responses, and we provide it as a

  2. Reliability analysis of wind embedded power generation system for ...

    African Journals Online (AJOL)

    This paper presents a method for Reliability Analysis of wind energy embedded in power generation system for Indian scenario. This is done by evaluating the reliability index, loss of load expectation, for the power generation system with and without integration of wind energy sources in the overall electric power system.

  3. SYSTEM ANALYSIS OF EXTERNAL POWER SUPPLY OF RAILWAYS TRACTION SUBSTATIONS

    Directory of Open Access Journals (Sweden)

    I.V. Domansky

    2013-06-01

    Full Text Available A system analysis of external power supply circuits of railways traction substations over the period of 1993 through 2011 and power supply circuits projects up to 2016 in the market economy environment and under standard requirements of the power industry of Ukraine is conducted

  4. Increasing power-law range in avalanche amplitude and energy distributions

    Science.gov (United States)

    Navas-Portella, Víctor; Serra, Isabel; Corral, Álvaro; Vives, Eduard

    2018-02-01

    Power-law-type probability density functions spanning several orders of magnitude are found for different avalanche properties. We propose a methodology to overcome empirical constraints that limit the range of truncated power-law distributions. By considering catalogs of events that cover different observation windows, the maximum likelihood estimation of a global power-law exponent is computed. This methodology is applied to amplitude and energy distributions of acoustic emission avalanches in failure-under-compression experiments of a nanoporous silica glass, finding in some cases global exponents in an unprecedented broad range: 4.5 decades for amplitudes and 9.5 decades for energies. In the latter case, however, strict statistical analysis suggests experimental limitations might alter the power-law behavior.

  5. Power system small signal stability analysis and control

    CERN Document Server

    Mondal, Debasish; Sengupta, Aparajita

    2014-01-01

    Power System Small Signal Stability Analysis and Control presents a detailed analysis of the problem of severe outages due to the sustained growth of small signal oscillations in modern interconnected power systems. The ever-expanding nature of power systems and the rapid upgrade to smart grid technologies call for the implementation of robust and optimal controls. Power systems that are forced to operate close to their stability limit have resulted in the use of control devices by utility companies to improve the performance of the transmission system against commonly occurring power system

  6. RELIABILITY ANALYSIS OF POWER DISTRIBUTION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Popescu V.S.

    2012-04-01

    Full Text Available Power distribution systems are basic parts of power systems and reliability of these systems at present is a key issue for power engineering development and requires special attention. Operation of distribution systems is accompanied by a number of factors that produce random data a large number of unplanned interruptions. Research has shown that the predominant factors that have a significant influence on the reliability of distribution systems are: weather conditions (39.7%, defects in equipment(25% and unknown random factors (20.1%. In the article is studied the influence of random behavior and are presented estimations of reliability of predominantly rural electrical distribution systems.

  7. Detection of Wind Turbine Power Performance Abnormalities Using Eigenvalue Analysis

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Sweeney, Christian Walsted; Marhadi, Kun Saptohartyadi

    2014-01-01

    Condition monitoring of wind turbines is a field of continu- ous research and development as new turbine configurations enter into the market and new failure modes appear. Systems utilising well established techniques from the energy and in- dustry sector, such as vibration analysis......, are commercially available and functioning successfully in fixed speed and vari- able speed turbines. Power performance analysis is a method specifically applicable to wind turbines for the detection of power generation changes due to external factors, such as ic- ing, internal factors, such as controller...... malfunction, or delib- erate actions, such as power de-rating. In this paper, power performance analysis is performed by sliding a time-power window and calculating the two eigenvalues corresponding to the two dimensional wind speed - power generation dis- tribution. The power is classified into five bins...

  8. Modular Trough Power Plant Cycle and Systems Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Price, H.; Hassani, V.

    2002-01-01

    This report summarizes an analysis to reduce the cost of power production from modular concentrating solar power plants through a relatively new and exciting concept that merges two mature technologies to produce distributed modular electric power in the range of 500 to 1,500 kWe. These are the organic Rankine cycle (ORC) power plant and the concentrating solar parabolic (CSP) trough technologies that have been developed independent of each other over many years.

  9. Development and Present Situation Analysis of Power Transformer State Maintenance

    Science.gov (United States)

    Lv, Sen; Li, Biao; Li, Huan

    2018-02-01

    The pivotal status of power transformer in the power system is one of the most important equipment. The safety and reliability of its operation is directly related to the safety and stability of power system. Based on the analysis of the present situation of power transformer state maintenance in home and abroad. The paper points out the deficiency of the current method and provides a theoretical basis for further research, which has a certain guiding significance.

  10. Increasing reliability of nuclear energy equipment and at nuclear power plants

    International Nuclear Information System (INIS)

    Ochrana, L.

    1997-01-01

    The Institute of Nuclear Energy at the Technical University in Brno cooperates with nuclear power plants in increasing their reliability. The teaching programme is briefly described. The scientific research programme of the Department of Heat and Nuclear Power Energy Equipment in the field of reliability is based on a complex systematic concept securing a high level of reliability. In 1996 the Department prepared a study dealing with the evaluation of the maintenance system in a nuclear power plant. The proposed techniques make it possible to evaluate the reliability and maintenance characteristics of any individual component in a nuclear power plant, and to monitor, record and evaluate data at any given time intervals. (M.D.)

  11. Uncertainty Analysis of Power Systems Using Collocation

    Science.gov (United States)

    2008-05-01

    sensitivity can be inferred and to construct surrogate models with which interpolation can be used to propagate PDF ?s. These techniques are applied to...with time and use. There is significant environmental interaction in the form of wind and waves; a large wave can partially of fully expose the...Power System We analyze uncertainty in a Simulink model describing the operation of a large pulse load reflecting the power consumption of a rail gun [8

  12. Dynamic power balance analysis in JET

    Science.gov (United States)

    Matthews, G. F.; Silburn, S. A.; Challis, C. D.; Eich, T.; Iglesias, D.; King, D.; Sieglin, B.; Contributors, JET

    2017-12-01

    The full scale realisation of nuclear fusion as an energy source requires a detailed understanding of power and energy balance in current experimental devices. In this we explore whether a global power balance model in which some of the calibration factors applied to the source or sink terms are fitted to the data can provide insight into possible causes of any discrepancies in power and energy balance seen in the JET tokamak. We show that the dynamics in the power balance can only be properly reproduced by including the changes in the thermal stored energy which therefore provides an additional opportunity to cross calibrate other terms in the power balance equation. Although the results are inconclusive with respect to the original goal of identifying the source of the discrepancies in the energy balance, we do find that with optimised parameters an extremely good prediction of the total power measured at the outer divertor target can be obtained over a wide range of pulses with time resolution up to ∼25 ms.

  13. Galena Electric Power A Situational Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Robert E. Chaney; Stephen G. Colt; Ronald A. Johnson; Richard W. Wiles; Gregory J. White

    2008-12-31

    The purpose of the investigation is to compare the economics of various electrical power generation options for the City of Galena. Options were assessed over a 30-year project period, beginning in 2010, and the final results were compared on the basis of residential customer electric rates ($/kWh). Galena's electric utility currently generates power using internal combustion diesel engines and generator sets. Nearby, there is an exposed coal seam, which might provide fuel for a power plant. Contributions to the energy mix might come from solar, municipal solid waste, or wood. The City has also been approached by Toshiba, Inc., as a demonstration site for a small (Model 4S) nuclear reactor power plant. The Yukon River is possibly a site for in-river turbines for hydroelectric power. This report summarizes the comparative economics of various energy supply options. This report covers: (1) thermal and electric load profiles for Galena; (2) technologies and resources available to meet or exceed those loads; (3) uses for any extra power produced by these options; (4) environmental and permitting issues and then; and (5) the overall economics of each of the primary energy options.

  14. Structural vulnerability analysis of electric power distribution grids

    NARCIS (Netherlands)

    Koc, Y.; Raman, Abhishek; Warnier, Martijn; Kumar, Tarun

    2016-01-01

    Power grid outages cause huge economical and societal costs. Disruptions in the power distribution grid are responsible for a significant fraction of electric power unavailability to customers. The impact of extreme weather conditions, continuously increasing demand, and the over-ageing of assets

  15. Increasing coal-fired power generation efficiency to reduce electric cost and environmental emissions

    International Nuclear Information System (INIS)

    Torrens, I.M.; Stenzel, W.C.

    1997-01-01

    New generating capacity required globally between 1993 and 2010 is estimated to be around 1500 GW, of which some two-thirds will be outside the OECD, and some 40 % in the Asian non-OECD countries. Coal is likely to account for a substantial fraction of this new generation. Today's state-of-the-art supercritical coal-fired power plant has a conversion efficiency of some 42-45 %. The capital cost increase associated with the supercritical or ultra-supercritical pulverized coal power plant compared to a conventional subcritical plant is small to negligible. The increased efficiency associated with the supercritical plant leads to an actual reduction in the total cost of electricity generated in cents/kWh, relative to a conventional plant. Despite this, the power sector continues to build subcritical plants and has no near term plans to increase the efficiency of power plants in the projects it is developing. Advanced clean coal technologies such as integrated gasification combined cycle and pressurized fluidized bed combustion will be selected for independent power projects only in very specific circumstances. Advanced clean coal plants can be operated reliably and with superior performance, and specifically that their present estimated capital costs can be reduced substantially to a point where they are competitive with state-of-the-art pulverized coal technologies. (R.P.)

  16. Plant operational states analysis in low power and shutdown PSA

    International Nuclear Information System (INIS)

    He Jiandong; Qiu Yongping; Zhang Qinfang; An Hongzhen; Li Maolin

    2013-01-01

    The purpose of Plant Operational States (POS) analysis is to disperse the continuous and dynamic process of low power and shutdown operation, which is the basis of developing event tree models for accident sequence analysis. According to the design of a 300 MW Nuclear Power Plant Project, operating experience and procedures of the reference plant, a detailed POS analysis is carried out based on relative criteria. Then, several kinds of POS are obtained, and the duration of each POS is calculated according to the operation records of the reference plant. The POS analysis is an important element in low power and shutdown PSA. The methodology and contents provide reference for POS analysis. (authors)

  17. Power law analysis of the human microbiome.

    Science.gov (United States)

    Ma, Zhanshan Sam

    2015-11-01

    Taylor's (1961, Nature, 189:732) power law, a power function (V = am(b) ) describing the scaling relationship between the mean and variance of population abundances of organisms, has been found to govern the population abundance distributions of single species in both space and time in macroecology. It is regarded as one of few generalities in ecology, and its parameter b has been widely applied to characterize spatial aggregation (i.e. heterogeneity) and temporal stability of single-species populations. Here, we test its applicability to bacterial populations in the human microbiome using extensive data sets generated by the US-NIH Human Microbiome Project (HMP). We further propose extending Taylor's power law from the population to the community level, and accordingly introduce four types of power-law extensions (PLEs): type I PLE for community spatial aggregation (heterogeneity), type II PLE for community temporal aggregation (stability), type III PLE for mixed-species population spatial aggregation (heterogeneity) and type IV PLE for mixed-species population temporal aggregation (stability). Our results show that fittings to the four PLEs with HMP data were statistically extremely significant and their parameters are ecologically sound, hence confirming the validity of the power law at both the population and community levels. These findings not only provide a powerful tool to characterize the aggregations of population and community in both time and space, offering important insights into community heterogeneity in space and/or stability in time, but also underscore the three general properties of power laws (scale invariance, no average and universality) and their specific manifestations in our four PLEs. © 2015 John Wiley & Sons Ltd.

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

    Directory of Open Access Journals (Sweden)

    Kumar Biswajit Debnath

    2018-03-01

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

  19. Long term energy performance analysis of Egbin thermal power ...

    African Journals Online (AJOL)

    This study is aimed at providing an energy performance analysis of Egbin thermal power plant. The plant operates on Regenerative Rankine cycle with steam as its working fluid .The model equations were formulated based on some performance parameters used in power plant analysis. The considered criteria were plant ...

  20. HRA qualitative analysis in a nuclear power plant

    International Nuclear Information System (INIS)

    Dai Licao; Zhang Li; Huang Shudong

    2004-01-01

    Human reliability analysis (HRA) is a very important part of probability safety assessment (PSA) in a nuclear power plant. Qualitative analysis is the basis and starting point of HRA. The purpose, the principle, the method and the procedure of qualitative HRA are introduced. SGTR, a pressurized nuclear power plant as an example, is used to illustrate it. (authors)

  1. Power Analysis of an Enterprise Wireless Communication Architecture

    Science.gov (United States)

    2017-09-01

    ANALYSIS OF AN ENTERPRISE WIRELESS COMMUNICATION ARCHITECTURE by Howen Q. Fernando September 2017 Thesis Advisor: Ronald Giachetti Second...TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE POWER ANALYSIS OF AN ENTERPRISE WIRELESS COMMUNICATION ARCHITECTURE 5. FUNDING NUMBERS 6...develops and analyzes a model to demonstrate that an enterprise computing architecture for Software Defined Radios results in significant power savings

  2. A NOVEL CONCEPT FOR REDUCING WATER USAGE AND INCREASING EFFICIENCY IN POWER GENERATION

    Energy Technology Data Exchange (ETDEWEB)

    Shiao-Hung Chiang; Guy Weismantel

    2004-03-01

    The objective of the project is to apply a unique ice thermal storage (ITS) technology to cooling the intake air to gas turbines used for power generation. In Phase I, the work includes theoretical analysis, computer simulation, engineering design and cost evaluation of this novel ITS technology. The study includes two typical gas turbines (an industrial and an aeroderivative type gas turbine) operated at two different geographic locations: Phoenix, AZ and Houston, TX. Simulation runs are performed to generate data for both power output (KW) and heat rate (Btu/KWh) as well as water recovery (acre ft/yr) in terms of intake air temperature and humidity based on weather data and turbine performance curves. Preliminary engineering design of a typical equipment arrangement for turbine inlet air-cooling operation using the ITS system is presented. A cost analysis has been performed to demonstrate the market viability of the ITS technology. When the ITS technology is applied to gas turbines, a net power gain up to 40% and a heat rate reduction as much as 7% can be achieved. In addition, a significant amount of water can be recovered (up to 200 acre-ft of water per year for a 50 MW turbine). The total cost saving is estimated to be $500,000/yr for a 50 MW gas turbine generator. These results have clearly demonstrated that the use of ITS technology to cool the intake-air to gas turbines is an efficient and cost effective means to improve the overall performance of its power generation capacity with an important added benefit of water recovery in power plant operation. Thus, further development of ITS technology for commercial applications in power generation, particularly in coal-based IGCC power plants is warranted.

  3. Stability analysis of spacecraft power systems

    Science.gov (United States)

    Halpin, S. M.; Grigsby, L. L.; Sheble, G. B.; Nelms, R. M.

    1990-01-01

    The problems in applying standard electric utility models, analyses, and algorithms to the study of the stability of spacecraft power conditioning and distribution systems are discussed. Both single-phase and three-phase systems are considered. Of particular concern are the load and generator models that are used in terrestrial power system studies, as well as the standard assumptions of load and topological balance that lead to the use of the positive sequence network. The standard assumptions regarding relative speeds of subsystem dynamic responses that are made in the classical transient stability algorithm, which forms the backbone of utility-based studies, are examined. The applicability of these assumptions to a spacecraft power system stability study is discussed in detail. In addition to the classical indirect method, the applicability of Liapunov's direct methods to the stability determination of spacecraft power systems is discussed. It is pointed out that while the proposed method uses a solution process similar to the classical algorithm, the models used for the sources, loads, and networks are, in general, more accurate. Some preliminary results are given for a linear-graph, state-variable-based modeling approach to the study of the stability of space-based power distribution networks.

  4. Increase of power output by change of ion transport direction in a plant microbial fuel cell

    NARCIS (Netherlands)

    Timmers, R.A.; Strik, D.P.B.T.B.; Hamelers, H.V.M.; Buisman, C.J.N.

    2013-01-01

    The plant microbial fuel cell (PMFC) is a technology for the production of renewable and clean bioenergy based on photosynthesis. To increase the power output of the PMFC, the internal resistance (IR) must be reduced. The objective of the present study was to reduce the membrane resistance by

  5. Wired: impacts of increasing power line use by a growing bird population

    Science.gov (United States)

    Moreira, Francisco; Encarnação, Vitor; Rosa, Gonçalo; Gilbert, Nathalie; Infante, Samuel; Costa, Julieta; D'Amico, Marcello; Martins, Ricardo C.; Catry, Inês

    2017-02-01

    Power lines are increasingly widespread across many regions of the planet. Although these linear infrastructures are known for their negative impacts on bird populations, through collision and electrocution, some species take advantage of electricity pylons for nesting. In this case, estimation of the net impact of these infrastructures at the population level requires an assessment of trade-offs between positive and negative impacts. We compiled historical information (1958-2014) of the Portuguese white stork Ciconia ciconia population to analyze long-term changes in numbers, distribution range and use of nesting structures. White stork population size increased 660% up to 12000 breeding pairs between 1984 and 2014. In the same period, the proportion of nests on electricity pylons increased from 1% to 25%, likely facilitated by the 60% increase in the length of the very high tension power line grid (holding the majority of the nests) in the stork’s distribution range. No differences in breeding success were registered for storks nesting on electricity pylons versus other structures, but a high risk of mortality by collision and electrocution with power lines was estimated. We discuss the implications of this behavioral change, and of the management responses by power line companies, both for stork populations and for managers.

  6. Weighting sequence variants based on their annotation increases power of whole-genome association studies

    DEFF Research Database (Denmark)

    Sveinbjornsson, Gardar; Albrechtsen, Anders; Zink, Florian

    2016-01-01

    for the family-wise error rate (FWER), using as weights the enrichment of sequence annotations among association signals. We show that this weighted adjustment increases the power to detect association over the standard Bonferroni correction. We use the enrichment of associations by sequence annotation we have...

  7. Increased Power Capture by Rotor Speed–Dependent Yaw Control of Wind Turbines

    DEFF Research Database (Denmark)

    Kragh, Knud Abildgaard; Fleming, Paul A.; Scholbrock, Andrew K.

    2013-01-01

    and tested. Results show that, with the correction scheme in place, the yaw alignment of the case turbine is improved and the yaw error is reduced to the vicinity of zero degrees. As a result of the improved yaw alignment, an increased power capture is observed for below-rated wind speeds....

  8. Validation of the thermal balance of Laguna Verde turbine under conditions of extended power increase

    International Nuclear Information System (INIS)

    Castaneda G, M. A.; Cruz B, H. J.; Mercado V, J. J.; Cardenas J, J. B.; Garcia de la C, F. M.

    2012-10-01

    The present work is a continuation of the task: Modeling of the vapor cycle of Laguna Verde with the PEPSE code to conditions of thermal power licensed at present (2027 MWt) in which the modeling of the vapor cycle of the nuclear power plant of Laguna Verde was realized with PEPSE code (Performance Evaluation of Power System Efficiencies). Once reached the conditions of nominal operation of extended power increase, operating both units to 2371 MWt; after the tests phase of starting-up and operation is necessary to carry out a verification of the proposed design of the vapor cycle for the new operation conditions. All this, having in consideration that the vapor cycle designer only knows the detail of the prospective performance of the main turbine, for all the other components (for example pumps, heat inter changers, valves, reactor, humidity separators and re-heaters, condensers, etc.) makes generic suppositions based on engineering judgment. This way carries out the calculations of thermal balance to determine the guaranteed gross power. The purpose of the present work is to comment the detail of the validation carried out of the specific thermal balance (thermal kit) of the nuclear power plant, making use of the design characteristics of the different components that conform the vapor cycle. (Author)

  9. Power Budget Analysis for High Altitude Airships

    Science.gov (United States)

    Choi, Sang H.; Elliott, James R.; King, Glen C.

    2006-01-01

    The High Altitude Airship (HAA) has various potential applications and mission scenarios that require onboard energy harvesting and power distribution systems. The energy source considered for the HAA s power budget is solar photon energy that allows the use of either photovoltaic (PV) cells or advanced thermoelectric (ATE) converters. Both PV cells and an ATE system utilizing high performance thermoelectric materials were briefly compared to identify the advantages of ATE for HAA applications in this study. The ATE can generate a higher quantity of harvested energy than PV cells by utilizing the cascaded efficiency of a three-staged ATE in a tandem mode configuration. Assuming that each stage of ATE material has the figure of merit of 5, the cascaded efficiency of a three-staged ATE system approaches the overall conversion efficiency greater than 60%. Based on this estimated efficiency, the configuration of a HAA and the power utility modules are defined.

  10. Nuclear power and sustainable development. Maintaining and increasing the overall assets available to future generations

    International Nuclear Information System (INIS)

    2002-01-01

    A central goal of sustainable development is to maintain or increase the overall assets available to future generations, while minimizing consumption of finite resources and not exceeding the carrying capacities of ecosystems. The development of nuclear power broadens the natural resource base usable for energy production, increases human and man-made capital, and, when safely handled, has little impact on ecosystems. Energy is essential for sustainable development. With continuing population and economic growth, and increasing needs in the developing world, substantially greater energy demand is a given, even taking into account continuing and accelerated energy efficiency and intensity improvements. Today, nuclear power is mostly utilized in industrialized countries that have the necessary technological, institutional and financial resources. Many of the industrialized countries that are able and willing to use nuclear power are also large energy consumers. Nuclear power currently generates 16% of the world's electricity. It produces virtually no sulfur dioxide, particulates, nitrogen oxides, volatile organic compounds or greenhouse gases. Globally, nuclear power currently avoids approximately 600 million tonnes of carbon emissions annually, about the same as hydropower. The 600 MtC avoided by nuclear power equals 8% of current global greenhouse gases emissions. In the OECD countries, nuclear power has for 35 years accounted for most of the reduction in the carbon intensity per unit of delivered energy. Existing operating nuclear power plants (NPPs) for which initial capital investments are largely depreciated are also often the most cost-effective way to reduce carbon emissions from electricity generation. In fact in the United States in 2000, NPPs were the most cost-effective way to generate electricity, irrespective of avoided carbon emissions. In other countries the advantages of existing nuclear generating stations are also increasingly recognized. Interest

  11. Power-Law Dynamics of Membrane Conductances Increase Spiking Diversity in a Hodgkin-Huxley Model.

    Science.gov (United States)

    Teka, Wondimu; Stockton, David; Santamaria, Fidel

    2016-03-01

    We studied the effects of non-Markovian power-law voltage dependent conductances on the generation of action potentials and spiking patterns in a Hodgkin-Huxley model. To implement slow-adapting power-law dynamics of the gating variables of the potassium, n, and sodium, m and h, conductances we used fractional derivatives of order η≤1. The fractional derivatives were used to solve the kinetic equations of each gate. We systematically classified the properties of each gate as a function of η. We then tested if the full model could generate action potentials with the different power-law behaving gates. Finally, we studied the patterns of action potential that emerged in each case. Our results show the model produces a wide range of action potential shapes and spiking patterns in response to constant current stimulation as a function of η. In comparison with the classical model, the action potential shapes for power-law behaving potassium conductance (n gate) showed a longer peak and shallow hyperpolarization; for power-law activation of the sodium conductance (m gate), the action potentials had a sharp rise time; and for power-law inactivation of the sodium conductance (h gate) the spikes had wider peak that for low values of η replicated pituitary- and cardiac-type action potentials. With all physiological parameters fixed a wide range of spiking patterns emerged as a function of the value of the constant input current and η, such as square wave bursting, mixed mode oscillations, and pseudo-plateau potentials. Our analyses show that the intrinsic memory trace of the fractional derivative provides a negative feedback mechanism between the voltage trace and the activity of the power-law behaving gate variable. As a consequence, power-law behaving conductances result in an increase in the number of spiking patterns a neuron can generate and, we propose, expand the computational capacity of the neuron.

  12. Analysis of chaos in high-dimensional wind power system.

    Science.gov (United States)

    Wang, Cong; Zhang, Hongli; Fan, Wenhui; Ma, Ping

    2018-01-01

    A comprehensive analysis on the chaos of a high-dimensional wind power system is performed in this study. A high-dimensional wind power system is more complex than most power systems. An 11-dimensional wind power system proposed by Huang, which has not been analyzed in previous studies, is investigated. When the systems are affected by external disturbances including single parameter and periodic disturbance, or its parameters changed, chaotic dynamics of the wind power system is analyzed and chaotic parameters ranges are obtained. Chaos existence is confirmed by calculation and analysis of all state variables' Lyapunov exponents and the state variable sequence diagram. Theoretical analysis and numerical simulations show that the wind power system chaos will occur when parameter variations and external disturbances change to a certain degree.

  13. Analysis of chaos in high-dimensional wind power system

    Science.gov (United States)

    Wang, Cong; Zhang, Hongli; Fan, Wenhui; Ma, Ping

    2018-01-01

    A comprehensive analysis on the chaos of a high-dimensional wind power system is performed in this study. A high-dimensional wind power system is more complex than most power systems. An 11-dimensional wind power system proposed by Huang, which has not been analyzed in previous studies, is investigated. When the systems are affected by external disturbances including single parameter and periodic disturbance, or its parameters changed, chaotic dynamics of the wind power system is analyzed and chaotic parameters ranges are obtained. Chaos existence is confirmed by calculation and analysis of all state variables' Lyapunov exponents and the state variable sequence diagram. Theoretical analysis and numerical simulations show that the wind power system chaos will occur when parameter variations and external disturbances change to a certain degree.

  14. Partial analysis of wind power limit in an electric micro system using continuation power flow

    International Nuclear Information System (INIS)

    Fiallo Guerrero, Jandry; Santos Fuentefria, Ariel; Castro Fernández, Miguel

    2013-01-01

    The wind power insertion in the power system is an important issue and can create some instability problems in voltage and system frequency due to stochastic origin of wind. Know the Wind Power Limit that can insert in an electric grid without losing stability is a very important matter. Existing in bibliography a few methods for calculation of wind power limit, some of them are based in static constrains, an example is a method based in a continuation power flow analysis. In the present work the method is applied in an electric micro system formed when the system is disconnected of the man grid, the main goal was prove the method in a weak and island network. The software used in the simulations was the Power System Analysis Toolbox (PSAT). (author)

  15. [Voluntary alpha-power increasing training impact on the heart rate variability].

    Science.gov (United States)

    Bazanova, O M; Balioz, N V; Muravleva, K B; Skoraia, M V

    2013-01-01

    In order to study the effect of the alpha EEG power increasing training at heart rate variability (HRV) as the index of the autonomic regulation of cognitive functions there were follow tasks: (1) to figure out the impact of biofeedback in the voluntary increasing the power in the individual high-frequency alpha-band effect on heart rate variability and related characteristics of cognitive and emotional spheres, (2) to determine the nature of the relationship between alpha activity indices and heart rate variability, depending on the alpha-frequency EEG pattern at rest (3) to examine how the individual alpha frequency EEG pattern is reflected in changes HRV as a result of biofeedback training. Psychometric indicators of cognitive performance, the characteristics of the alpha-EEG activity and heart rate variability (HRV) as LF/HF and pNN50 were recorded in 27 healthy men aged 18-34 years, before, during, and after 10 sessions of training of voluntary increase in alpha power in the individual high-frequency alpha band with eyes closed. To determine the biofeedback effect on the alpha power increasing training, data subjects are compared in 2 groups: experimental (14) with the real and the control group (13 people)--with mock biofeedback. The follow up effect of trainings was studied through month over the 10 training sessions. Results showed that alpha biofeedback training enhanced the fluency and accuracy in cognitive performance, decreased anxiety and frontal EMG, increased resting frequency, width and power in individual upper alpha range only in participants with low baseline alpha frequency. While mock biofeedback increased resting alpha power only in participants with high baseline resting alpha frequency and did change neither cognitive performance, nor HRV indices. Biofeedback training eliminated the alpha power decrease in response to arithmetic task in both with high and low alpha frequency participants and this effect was followed up over the month. Mock

  16. Artificial intelligence analysis of paraspinal power spectra.

    Science.gov (United States)

    Oliver, C W; Atsma, W J

    1996-10-01

    OBJECTIVE: As an aid to discrimination of sufferers with back pain an artificial intelligence neural network was constructed to differentiate paraspinal power spectra. DESIGN: Clinical investigation using surface electromyography. METHOD: The surface electromyogram power spectra from 60 subjects, 33 non-back-pain sufferers and 27 chronic back pain sufferers were used to construct a back propagation neural network that was then tested. Subjects were placed on a test frame in 30 degrees of lumbar forward flexion. An isometric load of two-thirds maximum voluntary contraction was held constant for 30 s whilst surface electromyograms were recorded at the level of the L(4-5). Paraspinal power spectra were calculated and loaded into the input layer of a three-layer back propagation network. The neural network classified the spectra into normal or back pain type. RESULTS: The back propagation neural was shown to have satisfactory convergence with a specificity of 79% and a sensitivity of 80%. CONCLUSIONS: Artificial intelligence neural networks appear to be a useful method of differentiating paraspinal power spectra in back-pain sufferers.

  17. Stability analysis of Centurion electric power system

    Energy Technology Data Exchange (ETDEWEB)

    Galu, Y.; Munda, J.L.; Jimoh, A.A. [Tshwane Univ. of Technology, Pretoria (South Africa)

    2008-07-01

    A Centurion electric power system was simulated. Data from a section of the Tshwane Municipality network in South Africa were used to evaluate the use of a power system stabilizer (PSS) and a flexible AC transmission system (FACTS) controller and a thyristor controlled series compensator (TCSC). The single-machine infinite bus (SMIB) power system model was used to validate the effectiveness of the systems under various disturbance scenarios. The system's synchronous generator was characterized as a higher order model. Thevenin's equivalent of the transmission network was used to reduce the single-machine infinite bus power system in relation to the reactance of the transformer, transmission line per circuit, and the impedance of the receiving end system. Three-phase faults were applied at the generator terminal busbar in order to evaluate the model's performance. The study demonstrated that use of the PSS and TCSC-based controllers provide an improved response in terms of both overshoot and settling time. 17 refs., 10 figs.

  18. Load Factor Analysis of P3TM's Power Supply for Accelerator Laboratory

    International Nuclear Information System (INIS)

    Suyamto; Yunanto

    2000-01-01

    The computation and analysis of P3TM's power supply for accelerator laboratory has been carried out. The purpose of analysis is to prepare the electrical energy which will be used for accelerator laboratory in the future. The load factor and residual electrical power was computed by using several data i.e electrical bill, energy consumption from April 1998 up to March 1999 and the peak current load out from transformer which is measured inside electrical central box. From the analysis it is known that the electrical load factor of P3TM is 27.4 %, power factor 0.78 and the average power consumption is 189.6 KVA. If the load forecasting factor is 50 %, the maximum electric power requirement for P3TM is about 300 KVA and the residual power supply is 390 KVA. If maximum electrical demand for accelerator is less than 390 KVA, then the electrical power for accelerator itself can be served by new special line for accelerator and by improving the power supply quality. In case the power level has to be increased, the most economical can be achieved by increasing electric power from 690 KVA to the optimum level of 860 KVA with condition that peak operational power of accelerator is less than 560 KVA. (author)

  19. Comparative analysis of the application of different Low Power Wide Area Network technologies in power grid

    Science.gov (United States)

    Wang, Hao; Sui, Hong; Liao, Xing; Li, Junhao

    2018-03-01

    Low Power Wide Area Network (LPWAN) technologies developed rapidly in recent years, but the application principle of different LPWAN technologies in power grid is still not clear. This paper gives a comparative analysis of two mainstream LPWAN technologies including NB-IoT and LoRa, and gives an application suggestion of these two LPWAN technologies, which can guide the planning and construction of LPWAN in power grid.

  20. Cooling intensification during quenching of power plant components - the way to increase reliability

    International Nuclear Information System (INIS)

    Borisov, I.A.

    1989-01-01

    To enchance the complex of mechanical properties and to increase operation time of large components of power facilities, regimes of accelerated cooling are developed. Results of heat treatment with accelerated cooling of turbine rotor of steel 26KhN3M2FAA, disks of turbine welded rotor of steel 20KhN2MFAA, components of steel 35KhN3MFA, are given. Special steels with carbon content less than 0.30% for details of power machine-building are developed

  1. Analysis and planning of the utilization of nuclear power plants

    International Nuclear Information System (INIS)

    Skvarka, P.

    1985-01-01

    The utilization coefficient as one of the characteristics of availability of nuclear power plants and the operation results (like maximum power, block number, and electric energy generation) are investigated by different statistic methods for several nuclear power plants with PWR type reactors and compared with those of WWER 440-type reactors. By means of linear many-parameter regression analysis the utilization coefficient is studied in dependence on block power and time after reactor commissioning. Forecastings of mean utilization coefficients are presented for the power of WWER 1000-type reactors

  2. Increasing the solar cell power output by coating with transition metal-oxide nanorods

    International Nuclear Information System (INIS)

    Kuznetsov, I.A.; Greenfield, M.J.; Mehta, Y.U.; Merchan-Merchan, W.; Salkar, G.; Saveliev, A.V.

    2011-01-01

    Highlights: → Nanoparticles enhance solar cell efficiency. → Solar cell power increase by nanorod coating. → Metal-oxide nanorods are prepared in flames. → Molybdenum oxide nanorods effectively scatter light on solar cell surface. → Scattering efficiency depends on coating density. -- Abstract: Photovoltaic cells produce electric current through interactions among photons from an ambient light source and electrons in the semiconductor layer of the cell. However, much of the light incident on the panel is reflected or absorbed without inducing the photovoltaic effect. Transition metal-oxide nanoparticles, an inexpensive product of a process called flame synthesis, can cause scattering of light. Scattering can redirect photon flux, increasing the fraction of light absorbed in the thin active layer of silicon solar cells. This research aims to demonstrate that the application of transition metal-oxide nanorods to the surface of silicon solar panels can enhance the power output of the panels. Several solar panels were coated with a nanoparticle-methanol suspension, and the power outputs of the panels before and after the treatment were compared. The results demonstrate an increase in power output of up to 5% after the treatment. The presence of metal-oxide nanorods on the surface of the coated solar cells is confirmed by electron microscopy.

  3. Effects of increased microwave heating power in the stellarator TJ-K

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, Alejandro; Koehn, Alf; Ali, Ahmed; Ramisch, Mirko [Institute of Interfacial Process Engineering and Plasma Technology, University of Stuttgart, Stuttgart (Germany)

    2015-05-01

    One of the microwave heating systems at the stellarator TJ-K has been recently upgraded: a third klystron has been installed, increasing the heating power from 4 kW to 6 kW operating at 14 GHz. A phased-array antenna is used which allows to vary the injection angle by sweeping the microwave frequency in order control the coupling mechanism of the microwave to the plasma. With the two klystrons already installed, ionization degrees of α ≅ 1 have been reached. We expect that an increased heating power, by means of the third klystron put into operation, leads to an increase in the electron temperature T{sub e} only, rather than in electron density n{sub e}, and thus a decrease in the collision frequency ν{sub ei} ∝ n{sub e}T{sub e}{sup -3/2} which has an impact on heating flow damping and neoclassical properties. Parameter scans have been performed in order to characterize the new heating scenario. A radial movable Langmuir probe has been used to obtain radial profiles of the electron density and temperature. An arrangement of bolometers and an optical diode have been used to obtain the power losses by radiation. A particle and power balance model is used to obtain estimated densities and temperatures in order to compare with the experimental results.

  4. Exergy analysis of the FIGUEIRA thermal power plant operation - state of Parana, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Stanescu, George; Lima, Joao E. [Parana Univ., Curitiba, PR (Brazil). Dept. de Engenharia Mecanica]. E-mails: stanescu@demec.ufpr.br; joeduli@demec.ufpr.br; Andrade, Carlos de [FIGUEIRA Thermal Power Plant, Figueira, PR (Brazil)]. E-mail: ccarlosaandrade@zipmail.com.br

    2000-07-01

    Exergy analysis is a powerful tool to evaluate, design and improve the thermal systems. The method of exergy analysis or availability analysis is well suited for furthering the goal of increasing the efficiency of existing power generation systems, and the capability of more effective energy resource use. Exergy analysis of the FIGUEIRA thermal power plant is presented. Exergy losses occurring in various components are considered and the exergy balance is shown in tabular form. Results clearly reveal that the steam generator is the principal site of thermodynamic losses, while the condenser is relatively unimportant. (author)

  5. Graphical analysis of power systems for mobile robotics

    Science.gov (United States)

    Raade, Justin William

    The field of mobile robotics places stringent demands on the power system. Energetic autonomy, or the ability to function for a useful operation time independent of any tether, refueling, or recharging, is a driving force in a robot designed for a field application. The focus of this dissertation is the development of two graphical analysis tools, namely Ragone plots and optimal hybridization plots, for the design of human scale mobile robotic power systems. These tools contribute to the intuitive understanding of the performance of a power system and expand the toolbox of the design engineer. Ragone plots are useful for graphically comparing the merits of different power systems for a wide range of operation times. They plot the specific power versus the specific energy of a system on logarithmic scales. The driving equations in the creation of a Ragone plot are derived in terms of several important system parameters. Trends at extreme operation times (both very short and very long) are examined. Ragone plot analysis is applied to the design of several power systems for high-power human exoskeletons. Power systems examined include a monopropellant-powered free piston hydraulic pump, a gasoline-powered internal combustion engine with hydraulic actuators, and a fuel cell with electric actuators. Hybrid power systems consist of two or more distinct energy sources that are used together to meet a single load. They can often outperform non-hybrid power systems in low duty-cycle applications or those with widely varying load profiles and long operation times. Two types of energy sources are defined: engine-like and capacitive. The hybridization rules for different combinations of energy sources are derived using graphical plots of hybrid power system mass versus the primary system power. Optimal hybridization analysis is applied to several power systems for low-power human exoskeletons. Hybrid power systems examined include a fuel cell and a solar panel coupled with

  6. Measurement and Analysis of Power in Hybrid System

    OpenAIRE

    Vartika Keshri; Prity Gupta

    2016-01-01

    Application with renewable energy  sources  such   as solar cell array, wind turbines, or fuel cells have increased significantly during the past decade. To obtain the clean energy, we are using the hybrid solar-wind power generation. Consumers prefer quality power from suppliers. The quality of power can be measured by using parameters such as voltage sag, harmonic and power factor.   To   obtain   quality   power   we   have different topologies. In our paper we present a new possible topol...

  7. Analog self-powered harvester achieving switching pause control to increase harvested energy

    Science.gov (United States)

    Makihara, Kanjuro; Asahina, Kei

    2017-05-01

    In this paper, we propose a self-powered analog controller circuit to increase the efficiency of electrical energy harvesting from vibrational energy using piezoelectric materials. Although the existing synchronized switch harvesting on inductor (SSHI) method is designed to produce efficient harvesting, its switching operation generates a vibration-suppression effect that reduces the harvested levels of electrical energy. To solve this problem, the authors proposed—in a previous paper—a switching method that takes this vibration-suppression effect into account. This method temporarily pauses the switching operation, allowing the recovery of the mechanical displacement and, therefore, of the piezoelectric voltage. In this paper, we propose a self-powered analog circuit to implement this switching control method. Self-powered vibration harvesting is achieved in this study by attaching a newly designed circuit to an existing analog controller for SSHI. This circuit aims to effectively implement the aforementioned new switching control strategy, where switching is paused in some vibration peaks, in order to allow motion recovery and a consequent increase in the harvested energy. Harvesting experiments performed using the proposed circuit reveal that the proposed method can increase the energy stored in the storage capacitor by a factor of 8.5 relative to the conventional SSHI circuit. This proposed technique is useful to increase the harvested energy especially for piezoelectric systems having large coupling factor.

  8. Systematic safety analysis of old nuclear power plants

    International Nuclear Information System (INIS)

    Dredemis, G.

    1985-11-01

    A program of systematic safety analysis of old nuclear power plants has been engaged by French safety authorities. Beyond the reshaping of safety documents (safety reports, general rules of operation, incidental and accidental procedures, internal emergency plan and manual of quality organization), this examination consisted of an analysis of the operation experience of circuits frequently actuated and a systematic analysis of safety circuits. This paper is based on the presentation of the exercise carried out at the Ardennes nuclear power plant operating for 15 years. This paper reviews also the main studies and modifications engaged on this power plant [fr

  9. Building 865 Hypersonic Wind Tunnel Power System Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Larry X. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-02-01

    This report documents the characterization and analysis of a high current power supply for the building 865 Hypersonic Wind Tunnel at Sandia National Laboratories. The system described in this report became operational in 2013, replacing the original 1968 system which employed an induction voltage regulator. This analysis and testing was completed to help the parent organization understand why an updated and redesigned power system was not delivering adequate power to resistive heater elements in the HWT. This analysis led to an improved understanding of the design and operation of the revised 2013 power supply system and identifies several reasons the revised system failed to achieve the performance of the original power supply installation. Design modifications to improve the performance of this system are discussed.

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

    International Nuclear Information System (INIS)

    Mewton, Ross T.; Cacho, Oscar J.

    2011-01-01

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

  11. Analyzing the Impacts of Increased Wind Power on Generation Revenue Sufficiency

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qin; Wu, Hongyu; Tan, Jin; Hodge, Bri-Mathias; Li, Wanning; Luo, Cheng

    2016-11-14

    The Revenue Sufficiency Guarantee (RSG), as part of make-whole (or uplift) payments in electricity markets, is designed to recover the generation resources' offer-based production costs that are not otherwise covered by their market revenues. Increased penetrations of wind power will bring significant impacts to the RSG payments in the markets. However, literature related to this topic is sparse. This paper first reviews the industrial practices of implementing RSG in major U.S. independent system operators (ISOs) and regional transmission operators (RTOs) and then develops a general RSG calculation method. Finally, an 18-bus test system is adopted to demonstrate the impacts of increased wind power on RSG payments.

  12. Analyzing the Impacts of Increased Wind Power on Generation Revenue Sufficiency: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qin; Wu, Hongyu; Tan, Jin; Hodge, Bri-Mathias; Li, Wanning; Luo, Cheng

    2016-08-01

    The Revenue Sufficiency Guarantee (RSG), as part of make-whole (or uplift) payments in electricity markets, is designed to recover the generation resources' offer-based production costs that are not otherwise covered by their market revenues. Increased penetrations of wind power will bring significant impacts to the RSG payments in the markets. However, literature related to this topic is sparse. This paper first reviews the industrial practices of implementing RSG in major U.S. independent system operators (ISOs) and regional transmission operators (RTOs) and then develops a general RSG calculation method. Finally, an 18-bus test system is adopted to demonstrate the impacts of increased wind power on RSG payments.

  13. Power Assigning Method for Increasing the Number of Users in Time-spreading Optical CDMA Systems

    Science.gov (United States)

    Salehi, Mohammad Reza; Abiri, Ebrahim; Kazemi, Keyvan; Dezfouli, Mehran

    2011-04-01

    In this paper, a method for increasing the number of supportable users in a time-spreading Optical code division multiple access (OCDMA) system is proposed. In the presented technique, a unique codeword is assigned to a couple of users instead of just one. Different optical powers are employed for such users in order to distinguish them from each other. Other methods use the frequency or the polarization of the optical signals as an additional coding dimension to increase the number of codewords and hence the number of users in the network. It is proposed to employ nonlinear optical regenerators for separating optical pulses with different powers. A comprehensive design algorithm for such regenerators is presented. In order to evaluate the performance of the designed regenerators a TS-OCDMA system is simulated using OptiSystem software. Results indicate an error free transmission in the system employing the proposed technique.

  14. Energy analysis of the solar power satellite.

    Science.gov (United States)

    Herendeen, R A; Kary, T; Rebitzer, J

    1979-08-03

    The energy requirements to build and operate the proposed Solar Power Satellite are evaluated and compared with the energy it produces. Because the technology is so speculative, uncertainty is explicitly accounted for. For a proposed 10-gigawatt satellite system, the energy ratio, defined as the electrical energy produced divided by the primary nonrenewable energy required over the lifetime of the system, is of order 2, where a ratio of 1 indicates the energy breakeven point. This is significantly below the energy ratio of today's electricity technologies such as light-water nuclear or coal-fired electric plants.

  15. Power Law Analysis of Financial Index Dynamics

    Directory of Open Access Journals (Sweden)

    J. Tenreiro Machado

    2012-01-01

    Full Text Available Power law (PL and fractional calculus are two faces of phenomena with long memory behavior. This paper applies PL description to analyze different periods of the business cycle. With such purpose the evolution of ten important stock market indices (DAX, Dow Jones, NASDAQ, Nikkei, NYSE, S&P500, SSEC, HSI, TWII, and BSE over time is studied. An evolutionary algorithm is used for the fitting of the PL parameters. It is observed that the PL curve fitting constitutes a good tool for revealing the signal main characteristics leading to the emergence of the global financial dynamic evolution.

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

    DEFF Research Database (Denmark)

    Ebrahimzadeh, Esmaeil; Blaabjerg, Frede; Wang, Xiongfei

    2018-01-01

    power converters and buses are more sensitive and have significant contribution to the harmonic instability. In the approach, a power electronics based system is introduced as a Multi-Input Multi-Output (MIMO) dynamic system by means of a dynamic admittance matrix. Bus Participation Factors (PFs......) are calculated by the oscillatory mode sensitivity analysis versus the elements of the MIMO transfer function matrix. The PF analysis detects which power electronic converters or buses have a higher participation in harmonic instability excitation than others or at which buses such instability problems have...

  17. Analysis on energy consumption index system of thermal power plant

    Science.gov (United States)

    Qian, J. B.; Zhang, N.; Li, H. F.

    2017-05-01

    Currently, the increasingly tense situation in the context of resources, energy conservation is a realistic choice to ease the energy constraint contradictions, reduce energy consumption thermal power plants has become an inevitable development direction. And combined with computer network technology to build thermal power “small index” to monitor and optimize the management system, the power plant is the application of information technology and to meet the power requirements of the product market competition. This paper, first described the research status of thermal power saving theory, then attempted to establish the small index system and build “small index” monitoring and optimization management system in thermal power plant. Finally elaborated key issues in the field of small thermal power plant technical and economic indicators to be further studied and resolved.

  18. New trends in design and fabrication of signal and power cables to increase nuclear safety

    International Nuclear Information System (INIS)

    Salmen, Florin; Florescu, Gheorghe; Ionescu, Aurel

    2007-01-01

    contained halogens that lead to formation of fluorine chlorine, bromine, and iodine salts. The fluorine and chlorine were important for old types of cables and wires as atoms in plastic molecules; bromine was a component of flame protection additives. During burning, behavior of cables is very important for installation in buildings and also in power and control systems of the plants. When such cables are under flame influence they allow propagation of flame and produce smoke and fire and also corrosive and toxic gases. They develop smoke with high density (endangering the use of emergency exits) and make difficult the fire extinguishing. A disadvantage of these types of cables is that the isolation is not mechanically too resistant. The new type of cables with halogen free jackets are composed of polymers based on pure hydrocarbons. Polymers like polyethylene (PE) or polypropylene (PP) are halogen-free. This paper presents the behavior of halogen-free cables during accelerated ageing generated by thermal, abnormal conditions and nuclear environment conditions. The effect on availability of an electrical system as well as the reliability parameters of both types of cables are compared and presented in the paper. Aging mechanism, effects, and simulation were studied and the analysis of the test results is given as well. In conclusions, we evaluated the aging degradation after accelerated aging of polyethylene jacket and under continuous and intermittent heating condition. Contrary to general expectation, we found that intermittent heating to polyethylene cable jacket showed low aging degradation as compared with continuous heating. We also had evaluated accelerated aging degradation in radiation flux conditions similar to those in rooms 303 and 304 in Cernavoda NPP and we found an increase of rigidity of PVC jackets. This can be an inconvenient for cables laid on cable transporter

  19. Human reliability analysis of Lingao Nuclear Power Station

    International Nuclear Information System (INIS)

    Zhang Li; Huang Shudong; Yang Hong; He Aiwu; Huang Xiangrui; Zheng Tao; Su Shengbing; Xi Haiying

    2001-01-01

    The necessity of human reliability analysis (HRA) of Lingao Nuclear Power Station are analyzed, and the method and operation procedures of HRA is briefed. One of the human factors events (HFE) is analyzed in detail and some questions of HRA are discussed. The authors present the analytical results of 61 HFEs, and make a brief introduction of HRA contribution to Lingao Nuclear Power Station

  20. Integrated analysis software for bulk power system stability

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T.; Nagao, T.; Takahashi, K. [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

    1994-12-31

    This paper presents Central Research Inst.of Electric Power Industry - CRIEPI`s - own developed three softwares for bulk power network analysis and the user support system which arranges tremendous data necessary for these softwares with easy and high reliability. (author) 3 refs., 7 figs., 2 tabs.

  1. Performance and stability analysis of a photovoltaic power system

    Science.gov (United States)

    Merrill, W. C.; Blaha, R. J.; Pickrell, R. L.

    1978-01-01

    The performance and stability characteristics of a 10 kVA photovoltaic power system are studied using linear Bode analysis and a nonlinear analog simulation. Power conversion efficiencies, system stability, and system transient performance results are given for system operation at various levels of solar insolation. Additionally, system operation and the modeling of system components for the purpose of computer simulation are described.

  2. Comparative Life-Cycle Cost Analysis Of Solar Photovoltaic Power ...

    African Journals Online (AJOL)

    Many homes in Nigeria are in remote locations where grid electricity supply could not be extended. This paper attempts to present a concise life-cycle-cost comparison of diesel generator power supply system and photovoltaic power system for a remote rural application. In this comparative analysis, conceptual designs ...

  3. Power Analysis in Two-Level Unbalanced Designs

    Science.gov (United States)

    Konstantopoulos, Spyros

    2010-01-01

    Previous work on statistical power has discussed mainly single-level designs or 2-level balanced designs with random effects. Although balanced experiments are common, in practice balance cannot always be achieved. Work on class size is one example of unbalanced designs. This study provides methods for power analysis in 2-level unbalanced designs…

  4. Increased installation in existing hydro power plants. Potentials and costs; Oekt installasjon i eksisterende kraftverk. Potensial og kostnader

    Energy Technology Data Exchange (ETDEWEB)

    Stensby, Kjell Erik (ed.)

    2011-06-15

    This report seeks to highlight the costs associated with increased installed capacity of existing hydropower plants. Five selected power plant is further studied. Furthermore, given an overview of the technical possibilities of power expansions in Norway. (AG)

  5. High resolving power spectrometer for beam analysis

    Science.gov (United States)

    Moshammer, H. W.; Spencer, J. E.

    1992-03-01

    We describe a system designed to analyze the high energy, closely spaced bunches from individual RF pulses. Neither a large solid angle nor momentum range is required so this allows characteristics that appear useful for other applications such as ion beam lithography. The spectrometer is a compact, double-focusing QBQ design whose symmetry allows the Quads to range between F or D with a correspondingly large range of magnifications, dispersion, and resolving power. This flexibility insures the possibility of spatially separating all of the bunches along the focal plane with minimal transverse kicks and bending angle for differing input conditions. The symmetry of the system allows a simple geometric interpretation of the resolving power in terms of thin lenses and ray optics. We discuss the optics and the hardware that is proposed to measure emittance, energy, energy spread, and bunch length for each bunch in an RF pulse train for small bunch separations. We also discuss how to use such measurements for feedback and feedforward control of these bunch characteristics as well as maintain their stability.

  6. Optimal rate of power increase in nuclear fuel. Pellet behaviour under dynamic conditions

    International Nuclear Information System (INIS)

    Karlsson, B.G.

    1976-05-01

    A mathematical model has been worked out for the determination of the optium power escalation rate for nuclear power plants from the view-pint of fuel integrity. The model calculates the stress and strain transients in the pellet-cladding system with rapid power increase. No burnup effects are included due to the short time scale involved. An elastic solution has been transposed to a linear viscoelastic one using the correspondence principle. The cladding has however been treated under the programme assumptions as purely elastic. The fuel material has been assumed to be completely relaxed prior to the power transient. Radial cracking is included. The UO 2 -material distortion has been assumed to be linear viscoelastic, while the dilation is assumed as elastic. The system has been treated assuming plane strain since friction between the pellet and the cladding is large with practical burnsups, and the pellet column can be regarded as infinitely long, compared to the diameter of the pellet. The results of the calculations made show that under the above assumptions the clad stress is independent of the rate of power increase in the pellet. Scince this result is in opposition to general opinion an experimental programme was performed in order to test the results of the model. These results were confirmed. The occurance of clad failures in practice is not determined purely by clad straining. Current thought pays attention to the influence of e.g. stress-corrosion phenomena as significant. The programme reported here pays no attention such-like effects, or the effects of clad creep which could be of considerable significance with local deformations. These later effects are receiving attention in work now being initiated at the Department.(author)

  7. The environment power system analysis tool development program

    Science.gov (United States)

    Jongeward, Gary A.; Kuharski, Robert A.; Kennedy, Eric M.; Stevens, N. John; Putnam, Rand M.; Roche, James C.; Wilcox, Katherine G.

    1990-01-01

    The Environment Power System Analysis Tool (EPSAT) is being developed to provide space power system design engineers with an analysis tool for determining system performance of power systems in both naturally occurring and self-induced environments. The program is producing an easy to use computer aided engineering (CAE) tool general enough to provide a vehicle for technology transfer from space scientists and engineers to power system design engineers. The results of the project after two years of a three year development program are given. The EPSAT approach separates the CAE tool into three distinct functional units: a modern user interface to present information, a data dictionary interpreter to coordinate analysis; and a data base for storing system designs and results of analysis.

  8. Investigation into the absorptivity change in metals with increased laser power

    DEFF Research Database (Denmark)

    Blidegn, Kristian; Olsen, Flemmming Ove

    1996-01-01

    interaction. An increase which can not be explained by the increase in temperature only. The interaction between laser light and metals is a major physical phenomena in laser material processing. The Drude free electron model or simplifications like the Hagen-Rubens relation has often been used to model......At a first glance the low absorptivity of metals in the infrared (IR) makes the use of YAG and CO2 lasers in metal processing very inefficient. However industrial inert gas cutting abilities demonstrates that the absorptivity can reach significantly higher levels during the high power laser...

  9. Exergy Analysis of Combined Cycle Power Plant: NTPC Dadri, India

    OpenAIRE

    Tiwari, Arvind; Hasan, M; Islam, Mohd.

    2012-01-01

    The aim of the present paper is to exergy analysis of combined Brayton/Rankine power cycle of NTPC Dadri India. Theoretical exergy analysis is carried out for different components of dadri combined cycle power plant which consists of a gas turbine unit, heat recovery steam generator without extra fuel consumption and steam turbine unit. The results pinpoint that more exergy losses occurred in the gas turbine combustion chamber. Its reached 35% of the total exergy losses while the exergy losse...

  10. THERMOECONOMIC ANALYSIS AND OPTIMIZATION OF GAS TURBINE POWER PLANT

    OpenAIRE

    Siahaya, Yusuf

    2009-01-01

    A gas turbine power plant, which will be located in Jakarta, will analyzed with the aid of exergy, exergoeconomics and optimization. An exergy analysis identifies the real thermodynacs inefficiency due to irreversibility destroyed within a gas turbine power plant system. An exergoeconomics or thermodynamic analysis consists of an exergy, an economic, an exergy costing, an exergoeconomic, and an exergoeconomic optimization aims at minimizing the thermodynamic inefficiencies (exergy...

  11. Electric Power quality Analysis in research reactor: Impacts on nuclear safety assessment and electrical distribution reliability

    International Nuclear Information System (INIS)

    Touati, Said; Chennai, Salim; Souli, Aissa

    2015-01-01

    The increased requirements on supervision, control, and performance in modern power systems make power quality monitoring a common practise for utilities. Large databases are created and automatic processing of the data is required for fast and effective use of the available information. Aim of the work presented in this paper is the development of tools for analysis of monitoring power quality data and in particular measurements of voltage and currents in various level of electrical power distribution. The study is extended to evaluate the reliability of the electrical system in nuclear plant. Power Quality is a measure of how well a system supports reliable operation of its loads. A power disturbance or event can involve voltage, current, or frequency. Power disturbances can originate in consumer power systems, consumer loads, or the utility. The effect of power quality problems is the loss power supply leading to severe damage to equipments. So, we try to track and improve system reliability. The assessment can be focused on the study of impact of short circuits on the system, harmonics distortion, power factor improvement and effects of transient disturbances on the Electrical System during motor starting and power system fault conditions. We focus also on the review of the Electrical System design against the Nuclear Directorate Safety Assessment principles, including those extended during the last Fukushima nuclear accident. The simplified configuration of the required system can be extended from this simple scheme. To achieve these studies, we have used a demo ETAP power station software for several simulations. (authors)

  12. Utilization of graph theory in security analysis of power grid

    Directory of Open Access Journals (Sweden)

    Dalibor Válek

    2014-12-01

    Full Text Available This paper describes way how to use graph theory in security analysis. As an environment is used network of power lines and devices which are included here. Power grid is considered as a system of nodes which make together graph (network. On the simple example is applied Fiedler´s theory which is able to select the most important power lines of whole network. Components related to these lines are logicly ordered and considered by author´s modified analysis. This method has been improved and optimalized for risks related with illegal acts. Each power grid component has been connected with possible kind of attack and every of this device was gradually evaluated by five coefficients which takes values from 1 to 10. On the coefficient basis was assessed the level of risk. In the last phase the most risky power grid components have been selected. On the selected devices have been proposed security measures.

  13. Energy loss analysis of an integrated space power distribution system

    Science.gov (United States)

    Kankam, M. David; Ribeiro, P. F.

    1992-01-01

    The results of studies related to conceptual topologies of an integrated utility-like space power system are described. The system topologies are comparatively analyzed by considering their transmission energy losses as functions of mainly distribution voltage level and load composition. The analysis is expedited by use of a Distribution System Analysis and Simulation (DSAS) software. This recently developed computer program by the Electric Power Research Institute (EPRI) uses improved load models to solve the power flow within the system. However, present shortcomings of the software with regard to space applications, and incompletely defined characteristics of a space power system make the results applicable to only the fundamental trends of energy losses of the topologies studied. Accountability, such as included, for the effects of the various parameters on the system performance can constitute part of a planning tool for a space power distribution system.

  14. Analysis of power curves of Danish and foreign wind turbines

    International Nuclear Information System (INIS)

    Petersen, H.

    1995-12-01

    This report describes an analysis of power curves for a number of wind turbines, 30 Danish and 17 foreign - European - wind turbines. The investigation is limited to wind turbines of 150 kW capacity and greater, and to wind turbines for which a power curve is available. The power curves are transformed into a common, uniform presentation in order to facilitate the succeeding treatment, which primarily is the calculation of the production of electrical energy yielded per year. From the known data of the wind turbine, equipped generator power and rotor area and the area swept by the blades, the specific electrical production is calculated in three terms: yield per square meter of rotor area, yield per kW generator power and yield per square meter and per kilowatt generator power. Based on these findings a number of comparisons are established, such as comparisons of conceptual designs and technical- economical evaluations. (au)

  15. Integrated equipment for increasing and maintaining coolant pressure in primary circuit of PWR nuclear power plant

    International Nuclear Information System (INIS)

    Sykora, D.

    1986-01-01

    An open heat pump circuit is claimed connected to the primary circuit. The pump circuit consists of a steam pressurizer with a built-in steam distributor, a compressor, an expander, a reducing valve, an auxiliary pump, and of water and steam pipes. The operation is described and a block diagram is shown of integrated equipment for increasing and maintaining pressure in the nuclear power plant primary circuit. The appropriate entropy diagram is also shown. The advantage of the open pump circuit consists in reducing the electric power input and electric power consumption for the steam pressurizers, removing entropy loss in heat transfer with high temperature gradient, in the possibility of inserting, between the expander and the auxiliary pump, a primary circuit coolant treatment station, in simplified design and manufacture of the high-pressure steam pressurizer vessel, reducing the weight of the steam pressurizer by changing its shape from cylindrical to spherical, increasing the rate of pressure growth in the primary circuit. (E.S.)

  16. Appreciation analysis for power supply companies; Wertsteigerungsanalyse fuer Energieversorgungsunternehmen

    Energy Technology Data Exchange (ETDEWEB)

    Muche, T. [Hochschule Zittau/Goerlitz (Germany)

    2007-08-15

    In view of the probable future consolidation in the energy economy with municipal undertakings increasingly becoming subject to takeovers and participations issues of shareholder value are a matter of growing interest for power supply companies. Amongst other advantages, having a high shareholder value guards against unwanted takeovers. However, it is not enough for companies merely to know their shareholder value; they must rather have their entire operative and strategic planning and control instruments geared to it. This forms the background to a pilot project at Goerlitz/Zittau University which was dedicated to an analysis of the shareholder value of municipal undertakings on the basis of year-end financial and capital market data.

  17. Multi-Mission Power Analysis Tool (MMPAT) Version 3

    Science.gov (United States)

    Wood, Eric G.; Chang, George W.; Chen, Fannie C.

    2012-01-01

    The Multi-Mission Power Analysis Tool (MMPAT) simulates a spacecraft power subsystem including the power source (solar array and/or radioisotope thermoelectric generator), bus-voltage control, secondary battery (lithium-ion or nickel-hydrogen), thermostatic heaters, and power-consuming equipment. It handles multiple mission types including heliocentric orbiters, planetary orbiters, and surface operations. Being parametrically driven along with its user-programmable features can reduce or even eliminate any need for software modifications when configuring it for a particular spacecraft. It provides multiple levels of fidelity, thereby fulfilling the vast majority of a project s power simulation needs throughout the lifecycle. It can operate in a stand-alone mode with a graphical user interface, in batch mode, or as a library linked with other tools. This software can simulate all major aspects of a spacecraft power subsystem. It is parametrically driven to reduce or eliminate the need for a programmer. Added flexibility is provided through user-designed state models and table-driven parameters. MMPAT is designed to be used by a variety of users, such as power subsystem engineers for sizing power subsystem components; mission planners for adjusting mission scenarios using power profiles generated by the model; system engineers for performing system- level trade studies using the results of the model during the early design phases of a spacecraft; and operations personnel for high-fidelity modeling of the essential power aspect of the planning picture.

  18. Analysis the Transient Process of Wind Power Resources when there are Voltage Sags in Distribution Grid

    Science.gov (United States)

    Nhu Y, Do

    2018-03-01

    Vietnam has many advantages of wind power resources. Time by time there are more and more capacity as well as number of wind power project in Vietnam. Corresponding to the increase of wind power emitted into national grid, It is necessary to research and analyze in order to ensure the safety and reliability of win power connection. In national distribution grid, voltage sag occurs regularly, it can strongly influence on the operation of wind power. The most serious consequence is the disconnection. The paper presents the analysis of distribution grid's transient process when voltage is sagged. Base on the analysis, the solutions will be recommended to improve the reliability and effective operation of wind power resources.

  19. Power system stability modelling, analysis and control

    CERN Document Server

    Sallam, Abdelhay A

    2015-01-01

    This book provides a comprehensive treatment of the subject from both a physical and mathematical perspective and covers a range of topics including modelling, computation of load flow in the transmission grid, stability analysis under both steady-state and disturbed conditions, and appropriate controls to enhance stability.

  20. Application of PSAT to Load Flow Analysis with STATCOM under Load Increase Scenario and Line Contingencies

    Science.gov (United States)

    Telang, Aparna S.; Bedekar, P. P.

    2017-09-01

    Load flow analysis is the initial and essential step for any power system computation. It is required for choosing better options for power system expansion to meet with ever increasing load demand. Implementation of Flexible AC Transmission System (FACTS) device like STATCOM, in the load flow, which is having fast and very flexible control, is one of the important tasks for power system researchers. This paper presents a simple and systematic approach for steady state power flow calculations with FACTS controller, static synchronous compensator (STATCOM) using command line usage of MATLAB tool-power system analysis toolbox (PSAT). The complexity of MATLAB language programming increases due to incorporation of STATCOM in an existing Newton-Raphson load flow algorithm. Thus, the main contribution of this paper is to show how command line usage of user friendly MATLAB tool, PSAT, can extensively be used for quicker and wider interpretation of the results of load flow with STATCOM. The novelty of this paper lies in the method of applying the load increase pattern, where the active and reactive loads have been changed simultaneously at all the load buses under consideration for creating stressed conditions for load flow analysis with STATCOM. The performance have been evaluated on many standard IEEE test systems and the results for standard IEEE-30 bus system, IEEE-57 bus system, and IEEE-118 bus system are presented.

  1. Local exome sequences facilitate imputation of less common variants and increase power of genome wide association studies.

    Directory of Open Access Journals (Sweden)

    Peter K Joshi

    Full Text Available The analysis of less common variants in genome-wide association studies promises to elucidate complex trait genetics but is hampered by low power to reliably detect association. We show that addition of population-specific exome sequence data to global reference data allows more accurate imputation, particularly of less common SNPs (minor allele frequency 1-10% in two very different European populations. The imputation improvement corresponds to an increase in effective sample size of 28-38%, for SNPs with a minor allele frequency in the range 1-3%.

  2. Probabilistic safety analysis of DC power supply requirements for nuclear power plants. Technical report

    International Nuclear Information System (INIS)

    Baranowsky, P.W.; Kolaczkowski, A.M.; Fedele, M.A.

    1981-04-01

    A probabilistic safety assessment was performed as part of the Nuclear Regulatory Commission generic safety task A-30, Adequacy of Safety Related DC Power Supplies. Event and fault tree analysis techniques were used to determine the relative contribution of DC power related accident sequences to the total core damage probability due to shutdown cooling failures. It was found that a potentially large DC power contribution could be substantially reduced by augmenting the minimum design and operational requirements. Recommendations included (1) requiring DC power divisional independence, (2) improved test, maintenance, and surveillance, and (3) requiring core cooling capability be maintained following the loss of one DC power bus and a single failure in another system

  3. Increase of the Integration Degree of Wind Power Plants into the Energy System Using Wind Forecasting and Power Consumption Predictor Models by Transmission System Operator

    Directory of Open Access Journals (Sweden)

    Manusov V.Z.

    2017-12-01

    Full Text Available Wind power plants’ (WPPs high penetration into the power system leads to various inconveniences in the work of system operators. This fact is associated with the unpredictable nature of wind speed and generated power, respectively. Due to these factors, such source of electricity must be connected to the power system to avoid detrimental effects on the stability and quality of electricity. The power generated by the WPPs is not regulated by the system operator. Accurate forecasting of wind speed and power, as well as power load can solve this problem, thereby making a significant contribution to improving the power supply systems reliability. The article presents a mathematical model for the wind speed prediction, which is based on autoregression and fuzzy logic derivation of Takagi-Sugeno. The new model of wavelet transform has been developed, which makes it possible to include unnecessary noise from the model, as well as to reveal the cycling of the processes and their trend. It has been proved, that the proposed combination of methods can be used simultaneously to predict the power consumption and the wind power plant potential power at any time interval, depending on the planning horizon. The proposed models support a new scientific concept for the predictive control system of wind power stations and increase their degree integration into the electric power system.

  4. Nuclear power company activity based costing management analysis

    International Nuclear Information System (INIS)

    Xu Dan

    2012-01-01

    With Nuclear Energy Industry development, Nuclear Power Company has the continual promoting stress of inner management to the sustainable marketing operation development. In view of this, it is very imminence that Nuclear Power Company should promote the cost management levels and built the nuclear safety based lower cost competitive advantage. Activity based costing management (ABCM) transfer the cost management emphases from the 'product' to the 'activity' using the value chain analysis methods, cost driver analysis methods and so on. According to the analysis of the detail activities and the value chains, cancel the unnecessary activity, low down the resource consuming of the necessary activity, and manage the cost from the source, achieve the purpose of reducing cost, boosting efficiency and realizing the management value. It gets the conclusion from the detail analysis with the nuclear power company procedure and activity, and also with the selection to 'pieces analysis' of the important cost related project in the nuclear power company. The conclusion is that the activities of the nuclear power company has the obviously performance. It can use the management of ABC method. And with the management of the procedure and activity, it is helpful to realize the nuclear safety based low cost competitive advantage in the nuclear power company. (author)

  5. Power generation using sugar cane bagasse: A heat recovery analysis

    Science.gov (United States)

    Seguro, Jean Vittorio

    The sugar industry is facing the need to improve its performance by increasing efficiency and developing profitable by-products. An important possibility is the production of electrical power for sale. Co-generation has been practiced in the sugar industry for a long time in a very inefficient way with the main purpose of getting rid of the bagasse. The goal of this research was to develop a software tool that could be used to improve the way that bagasse is used to generate power. Special focus was given to the heat recovery components of the co-generation plant (economizer, air pre-heater and bagasse dryer) to determine if one, or a combination, of them led to a more efficient co-generation cycle. An extensive review of the state of the art of power generation in the sugar industry was conducted and is summarized in this dissertation. Based on this models were developed. After testing the models and comparing the results with the data collected from the literature, a software application that integrated all these models was developed to simulate the complete co-generation plant. Seven different cycles, three different pressures, and sixty-eight distributions of the flue gas through the heat recovery components can be simulated. The software includes an economic analysis tool that can help the designer determine the economic feasibility of different options. Results from running the simulation are presented that demonstrate its effectiveness in evaluating and comparing the different heat recovery components and power generation cycles. These results indicate that the economizer is the most beneficial option for heat recovery and that the use of waste heat in a bagasse dryer is the least desirable option. Quantitative comparisons of several possible cycle options with the widely-used traditional back-pressure turbine cycle are given. These indicate that a double extraction condensing cycle is best for co-generation purposes. Power generation gains between 40 and

  6. THERMODYNAMIC ANALYSIS OF CARBON SEQUESTRATION METHODS IN LIGNITE POWER PLANTS

    International Nuclear Information System (INIS)

    Koroneos J. Christopher; Sakiltzis Christos; Rovas C. Dimitrios

    2008-01-01

    The green house effect is a very pressing issue of our times due to the big impact it will have in the future of life in our planet. The temperature increase of the earth which is the major impact of the greenhouse effect may change forever the climate and the way of life in many countries. It may lead to the reduction of agricultural production and at the end to famine, in several nations. The minimization of CO2 emissions and the introduction of new energy sources is the only solution to the catastrophe that is coming if inaction prevails. The objective of this work is to analyze the methods of the CO2 removal from the flue gases of power plants that use solid fuels. It is especially fit to the Greek conditions where the main fuel used is lignite. Three methods have been examined and compared thermodynamically. These are: (a) Removal of CO2 from the flue gas stream by absorption, (b) The combustion of lignite with pure oxygen and (c) The gasification of lignite. The lignite used in the analysis is the Greek lignite, produced at the Western Macedonia mines. The power plant, before carbon sequestration, has an efficiency of 39%, producing 330MW of electric power. After sequestration, the CO2 is compressed to pressures between 80-110 atm, before its final disposal. In the first method, the sequestration of CO2 is done utilizing a catalyst. The operation requires electricity and high thermal load which is received from low pressure steam extracted from the turbines. Additionally, electricity is required for the compression of the CO2 to 100 bars. This leads to a lower efficiency of the power plant by by 13%. In the second method, the lignite combustion is done with pure O2 produced at an air separation unit. The flue gasses are made up of CO2 and water vapor. This method requires electricity for carbon dioxide compression and the Air Separation unit, thus, the power plant efficiency is lowered by 26%. In the lignite gasification method, the products are a mixture of

  7. Accident analysis in nuclear power plants

    International Nuclear Information System (INIS)

    Silva, D.E. da

    1981-01-01

    The way the philosophy of Safety in Depth can be verified through the analysis of simulated accidents is shown. This can be achieved by verifying that the integrity of the protection barriers against the release of radioactivity to the environment is preserved even during accident conditions. The simulation of LOCA is focalized as an example, including a study about the associated environmental radiological consequences. (Author) [pt

  8. Wind farm electrical power production model for load flow analysis

    International Nuclear Information System (INIS)

    Segura-Heras, Isidoro; Escriva-Escriva, Guillermo; Alcazar-Ortega, Manuel

    2011-01-01

    The importance of renewable energy increases in activities relating to new forms of managing and operating electrical power: especially wind power. Wind generation is increasing its share in the electricity generation portfolios of many countries. Wind power production in Spain has doubled over the past four years and has reached 20 GW. One of the greatest problems facing wind farms is that the electrical power generated depends on the variable characteristics of the wind. To become competitive in a liberalized market, the reliability of wind energy must be guaranteed. Good local wind forecasts are therefore essential for the accurate prediction of generation levels for each moment of the day. This paper proposes an electrical power production model for wind farms based on a new method that produces correlated wind speeds for various wind farms. This method enables a reliable evaluation of the impact of new wind farms on the high-voltage distribution grid. (author)

  9. Improving Power System Stability Using Transfer Function: A Comparative Analysis

    Directory of Open Access Journals (Sweden)

    G. Shahgholian

    2017-10-01

    Full Text Available In this paper, a small-signal dynamic model of a single-machine infinite-bus (SMIB power system that includes IEEE type-ST1 excitation system and PSS based on transfer fu¬n¬c¬¬tion structure is presented. The changes in the operating co¬n¬dition of a power system on dynamic performance have been exa¬m¬ined. The dynamic performance of the closed-loop system is ana¬lyzed base on its eigenvalues. The effectiveness of the par¬a¬m¬e¬t¬ers changes on dynamic stability is verified by simulation res¬u¬l¬ts. Three types of PSS have been considered for analysis: (a the derivative PSS, (b the lead-lag PSS or conventional PSS, and (c the proportional-integral-derivative PSS. The objective fu¬nc¬t¬i¬o¬n is formulated to increase the dam¬¬ping ratio of the electromechanical mode eigenvalues. Simu¬la¬tion results show that the PID-PSS performs better for less ov¬e¬r¬shoot and less settling time comp¬ared with the CPSS and DPSS un¬der different load ope¬ration and the significant system pa¬r¬am¬eter variation conditions.

  10. Economic impact analysis of independent power projects in British Columbia

    International Nuclear Information System (INIS)

    2009-12-01

    Independent power producer (IPP) projects have been active in British Columbia's (BC) regulated electricity market since the late 1980s. The 49 IPP projects developed in the province currently account for approximately 10 per cent of BC's electricity generation, and IPP development continues to expand in nearly every region. This study presented an economic impact analysis of IPP projects in BC. The economic impacts of IPP projects were divided into 2 categories: (1) existing IPP projects, and (2) potential IPP projects. The study showed that the total power potential supplied by BC IPP projects would increase from a current level of 5940 annual GWh to approximately 14,149 GWh. BC could also be generating a further 21,321 GWh of annual output to service demand domestically in addition to exporting to the United States. The value of capital investment in existing IPPs across BC was estimated at $2.8 billion. Capital investment in potential IPPs was estimated at $26.1 billion in 2009 constant dollars. Government revenues generated through the construction phase of potential IPP projects were estimated at $1.6 billion. IPP projects are expected to have a significant impact on First Nations groups, contribute to provincial energy self-sufficiency, and have little to no greenhouse gas (GHG) emissions. 25 refs., 19 tabs., 24 figs.

  11. Economic analysis of power generation from floating solar chimney power plant

    International Nuclear Information System (INIS)

    Zhou, Xinping; Yang, Jiakuan; Xiao, Bo; Wang, Fen

    2009-01-01

    Solar chimney thermal power technology that has a long life span is a promising large-scale solar power generating technology. This paper performs economic analysis of power generation from floating solar chimney power plant (FSCPP) by analyzing cash flows during the whole service period of a 100 MW plant. Cash flows are influenced by many factors including investment, operation and maintenance cost, life span, payback period, inflation rate, minimum attractive rate of return, non-returnable subsidy rate, interest rate of loans, sale price of electricity, income tax rate and whether additional revenue generated by carbon credits is included or not. Financial incentives and additional revenue generated by carbon credits can accelerate the development of the FSCPP. Sensitivity analysis to examine the effects of the factors on cash flows of a 100 MW FSCPP is performed in detail. The results show that the minimum price for obtaining minimum attractive rate of return (MARR) of 8% reaches 0.83 yuan (kWh) -1 under financial incentives including loans at a low interest rate of 2% and free income tax. Comparisons of economics of the FSCPP and reinforced concrete solar chimney power plant or solar photovoltaic plant are also performed by analyzing their cash flows. It is concluded that FSCPP is in reality more economical than reinforced concrete solar chimney power plant (RCSCPP) or solar photovoltaic plant (SPVP) with the same power capacity. (author)

  12. Thermoeconomic Analysis of Hybrid Power Plant Concepts for Geothermal Combined Heat and Power Generation

    Directory of Open Access Journals (Sweden)

    Florian Heberle

    2014-07-01

    Full Text Available We present a thermo-economic analysis for a low-temperature Organic Rankine Cycle (ORC in a combined heat and power generation (CHP case. For the hybrid power plant, thermal energy input is provided by a geothermal resource coupled with the exhaust gases of a biogas engine. A comparison to alternative geothermal CHP concepts is performed by considering variable parameters like ORC working fluid, supply temperature of the heating network or geothermal water temperature. Second law efficiency as well as economic parameters show that hybrid power plants are more efficient compared to conventional CHP concepts or separate use of the energy sources.

  13. Investigation into the absorptivity change in metals with increased laser power

    DEFF Research Database (Denmark)

    Blidegn, Kristian; Olsen, Flemmming Ove

    1996-01-01

    At a first glance the low absorptivity of metals in the infrared (IR) makes the use of YAG and CO2 lasers in metal processing very inefficient. However industrial inert gas cutting abilities demonstrates that the absorptivity can reach significantly higher levels during the high power laser...... interaction. An increase which can not be explained by the increase in temperature only. The interaction between laser light and metals is a major physical phenomena in laser material processing. The Drude free electron model or simplifications like the Hagen-Rubens relation has often been used to model...... the processes.This paper discuss the need to extend the Drude mode taking into account interband transitions and anormal skin effect in order to describe in increase in absorptivity seen at high intensities. The absorption model will be used in a cut front simulation and results are compared with cutting...

  14. How Does Energy Storage Increase the Efficiency of an Electricity Market with Integrated Wind and Solar Power Generation?—A Case Study of Korea

    Directory of Open Access Journals (Sweden)

    Jung Youn Mo

    2017-10-01

    Full Text Available In recent years, increasing requests to reduce greenhouse gas emissions have led to renewable resources rapidly replacing conventional power sources. However, the inherent variability of renewable sources reduces the reliability of power systems. Energy storage has been proposed as a viable alternative, as it can mitigate the variability of renewable energy sources and increase the efficiency of power systems by lowering peak electricity demand. In this study, we evaluate the benefits of integrating energy storage with combined wind and solar power generation in the Korean power system through using the dynamic optimization method. Realistic wind and photovoltaic solar power generation scenarios were estimated for actual sites. The results show that the wind power-based system benefitted more from energy storage than the combined wind and solar photovoltaic power-based system. This is because the high variability of wind power was reduced when it was combined with solar power. Co-optimization for energy and reserve costs was more beneficial than optimization for energy costs alone, which suggests that the reliability offered by storage is an important cost-saving factor, in addition to the reduction of energy costs by price arbitrage. Finally, the analysis was conducted under various scenarios to determine the validity of energy storage cost effectiveness.

  15. Effect of increased regulation on capital costs and manual labor requirements of nuclear power plants

    International Nuclear Information System (INIS)

    Paik, S.; Schriver, W.R.

    1981-01-01

    An attempt is made to explain the impact of increasing governmental regulation on capital costs and labor requirements for constructing light water reactor (LWR) electric power plants. The principal factors contributing to these increases are: (1) market conditions and (2) increased regulation. General market conditions include additional costs attributable to price inflation of equipment, material, labor, and the increased cost of money. The central objective of this work is to estimate the impact of increasing regulation on plant costs and, conversely, on output. To do this it is necessary to isolate two opposing sets of forces which have been in operation during the period of major regulatory expansion: learning based upon plant design experience and economies of scale with increasing size (generating capacity) of newer plants. Conceptual models are specified to capture the independent effects of increasing regulation, learning, and economies of scale. Empirical results were obtained by estimating the models on data collected from industry experience during the 1967-1980 period. 23 refs

  16. Air quality impacts of increased use of indigenous fuels for power generation in the Philippines

    International Nuclear Information System (INIS)

    Orbeta, E.M.

    2003-01-01

    The 2002-2011 Philippine Energy plan promotes the restructuring of its troubled power sector to ensure efficiency, reliability in supply and competitive electricity pricing. In particular, the plan promotes the use of indigenous fuels to increase self-sufficiency and reduce dependence on imported fuels. However, the indigenous fuel that will replace imported oil includes coal (a highly polluting energy source) and geothermal power. This paper assessed the environmental and health impacts associated with the development of coal and geothermal energy in the Philippines. It was determined that from 2001 to 2011, the development of geothermal energy could result in less air pollution than a scenario in which only current energy sources are developed. However, the expected increase in generating capacity in the Philippines will result in a general increase in air pollution levels. Local coal is singled out as the primary polluting energy source. Several pollution reduction initiatives were recommended, including improved pollution monitoring and energy efficiency measures. 18 refs., 21 tabs., 4 figs., 8 appendices

  17. Shuttle Topography Data Inform Solar Power Analysis

    Science.gov (United States)

    2013-01-01

    The next time you flip on a light switch, there s a chance that you could be benefitting from data originally acquired during the Space Shuttle Program. An effort spearheaded by Jet Propulsion Laboratory (JPL) and the National Geospatial-Intelligence Agency (NGA) in 2000 put together the first near-global elevation map of the Earth ever assembled, which has found use in everything from 3D terrain maps to models that inform solar power production. For the project, called the Shuttle Radar Topography Mission (SRTM), engineers at JPL designed a 60-meter mast that was fitted onto Shuttle Endeavour. Once deployed in space, an antenna attached to the end of the mast worked in combination with another antenna on the shuttle to simultaneously collect data from two perspectives. Just as having two eyes makes depth perception possible, the SRTM data sets could be combined to form an accurate picture of the Earth s surface elevations, the first hight-detail, near-global elevation map ever assembled. What made SRTM unique was not just its surface mapping capabilities but the completeness of the data it acquired. Over the course of 11 days, the shuttle orbited the Earth nearly 180 times, covering everything between the 60deg north and 54deg south latitudes, or roughly 80 percent of the world s total landmass. Of that targeted land area, 95 percent was mapped at least twice, and 24 percent was mapped at least four times. Following several years of processing, NASA released the data to the public in partnership with NGA. Robert Crippen, a member of the SRTM science team, says that the data have proven useful in a variety of fields. "Satellites have produced vast amounts of remote sensing data, which over the years have been mostly two-dimensional. But the Earth s surface is three-dimensional. Detailed topographic data give us the means to visualize and analyze remote sensing data in their natural three-dimensional structure, facilitating a greater understanding of the features

  18. Tornado outbreak variability follows Taylor's power law of fluctuation scaling and increases dramatically with severity

    Science.gov (United States)

    Tippett, Michael K.; Cohen, Joel E.

    2016-01-01

    Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from ‘outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954–2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related. PMID:26923210

  19. Physical-chemical purification of power metal optics for increasing its service life

    Science.gov (United States)

    Filin, S. A.; Rogalin, V. E.; Kaplunov, I. A.; Zingerman, K. M.

    2017-12-01

    In order to increase the resource of power metal optics, the features of the choice of solvents for its physical and chemical cleaning are investigated. During cleaning, on the contaminated surface there remain visually observed white film of alkali and alkaline earth metal salts, insoluble by this class of solvents, and iridescent bands from the interaction of hydrocarbons with metal, and this degrades optical properties and reduces the life of mirrors. It is demonstrated that, with the use of solvents, it is necessary to inhibit the interaction of hydrocarbons with mirrors by the stabilization of solvents or by selection of cleaning regimes.

  20. k-Nearest Neighbors Algorithm in Profiling Power Analysis Attacks

    Directory of Open Access Journals (Sweden)

    Z. Martinasek

    2016-06-01

    Full Text Available Power analysis presents the typical example of successful attacks against trusted cryptographic devices such as RFID (Radio-Frequency IDentifications and contact smart cards. In recent years, the cryptographic community has explored new approaches in power analysis based on machine learning models such as Support Vector Machine (SVM, RF (Random Forest and Multi-Layer Perceptron (MLP. In this paper, we made an extensive comparison of machine learning algorithms in the power analysis. For this purpose, we implemented a verification program that always chooses the optimal settings of individual machine learning models in order to obtain the best classification accuracy. In our research, we used three datasets, the first containing the power traces of an unprotected AES (Advanced Encryption Standard implementation. The second and third datasets are created independently from public available power traces corresponding to a masked AES implementation (DPA Contest v4. The obtained results revealed some interesting facts, namely, an elementary k-NN (k-Nearest Neighbors algorithm, which has not been commonly used in power analysis yet, shows great application potential in practice.

  1. Small nuclear power reactor emergency electric power supply system reliability comparative analysis

    International Nuclear Information System (INIS)

    Bonfietti, Gerson

    2003-01-01

    This work presents an analysis of the reliability of the emergency power supply system, of a small size nuclear power reactor. Three different configurations are investigated and their reliability analyzed. The fault tree method is used as the main tool of analysis. The work includes a bibliographic review of emergency diesel generator reliability and a discussion of the design requirements applicable to emergency electrical systems. The influence of common cause failure influences is considered using the beta factor model. The operator action is considered using human failure probabilities. A parametric analysis shows the strong dependence between the reactor safety and the loss of offsite electric power supply. It is also shown that common cause failures can be a major contributor to the system reliability. (author)

  2. VISUAL AND STATISTICAL ANALYSIS OF DIGITAL ELEVATION MODELS GENERATED USING IDW INTERPOLATOR WITH VARYING POWERS

    Directory of Open Access Journals (Sweden)

    F. F. Asal

    2012-07-01

    Full Text Available Digital elevation data obtained from different Engineering Surveying techniques is utilized in generating Digital Elevation Model (DEM, which is employed in many Engineering and Environmental applications. This data is usually in discrete point format making it necessary to utilize an interpolation approach for the creation of DEM. Quality assessment of the DEM is a vital issue controlling its use in different applications; however this assessment relies heavily on statistical methods with neglecting the visual methods. The research applies visual analysis investigation on DEMs generated using IDW interpolator of varying powers in order to examine their potential in the assessment of the effects of the variation of the IDW power on the quality of the DEMs. Real elevation data has been collected from field using total station instrument in a corrugated terrain. DEMs have been generated from the data at a unified cell size using IDW interpolator with power values ranging from one to ten. Visual analysis has been undertaken using 2D and 3D views of the DEM; in addition, statistical analysis has been performed for assessment of the validity of the visual techniques in doing such analysis. Visual analysis has shown that smoothing of the DEM decreases with the increase in the power value till the power of four; however, increasing the power more than four does not leave noticeable changes on 2D and 3D views of the DEM. The statistical analysis has supported these results where the value of the Standard Deviation (SD of the DEM has increased with increasing the power. More specifically, changing the power from one to two has produced 36% of the total increase (the increase in SD due to changing the power from one to ten in SD and changing to the powers of three and four has given 60% and 75% respectively. This refers to decrease in DEM smoothing with the increase in the power of the IDW. The study also has shown that applying visual methods supported

  3. Covariate adjustments in randomized controlled trials increased study power and reduced biasedness of effect size estimation.

    Science.gov (United States)

    Lee, Paul H

    2016-08-01

    This study aims to show that under several assumptions, in randomized controlled trials (RCTs), unadjusted, crude analysis will underestimate the Cohen's d effect size of the treatment, and an unbiased estimate of effect size can be obtained only by adjusting for all predictors of the outcome. Four simulations were performed to examine the effects of adjustment on the estimated effect size of the treatment and power of the analysis. In addition, we analyzed data from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study (older adults aged 65-94), an RCT with three treatment arms and one control arm. We showed that (1) the number of unadjusted covariates was associated with the effect size of the treatment; (2) the biasedness of effect size estimation was minimized if all covariates were adjusted for; (3) the power of the statistical analysis slightly decreased with the number of adjusted noise variables; and (4) exhaustively searching the covariates and noise variables adjusted for can lead to exaggeration of the true effect size. Analysis of the ACTIVE study data showed that the effect sizes adjusting for covariates of all three treatments were 7.39-24.70% larger than their unadjusted counterparts, whereas the effect size would be elevated by at most 57.92% by exhaustively searching the variables adjusted for. All covariates of the outcome in RCTs should be adjusted for, and if the effect of a particular variable on the outcome is unknown, adjustment will do more good than harm. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Increase in Organization Effectiveness Using Voice Analysis: The System Approach

    Directory of Open Access Journals (Sweden)

    Lina Bartkienė

    2011-04-01

    Full Text Available The main purpose of this article is to analyze literature related to the system theory and to present the system of increase in organization effectiveness using voice analysis. The concepts of the system approach were analyzed, the definition of the system, its components and classification were discussed. Following the principles of the system theory, the system of increase in organization effectiveness using voice analysis was designed. Each element was briefly discussed, i.e. processes influencing the employee, the environment, voice analysis system, expert system, prime and final organizational effectiveness. In addition, the relations between these elements were indentified. Article in Lithuanian

  5. Combining Chalk Talk with PowerPoint to Increase In-class Student Engagement

    Directory of Open Access Journals (Sweden)

    Swati Betharia

    2016-11-01

    Full Text Available In striving to attain a higher degree of in-class student engagement, and target a larger number of preferred student-learning styles, this case study describes a multimodal teaching approach. PowerPoint slides have gradually gained popularity over the more traditional chalk and talk lecture design. The student population in today’s age seeks more non-passive modes of information delivery. Numerous novel approaches to enhance active learning, such as flipped classroom and problem-based learning, have recently been explored. While working well for therapeutic and lab-based courses, these formats may not be best-suited for all basic science topics. The importance of basic science in a pharmacy curriculum is well emphasized in the 2016 ACPE Standards. To actively involve students in a pharmacology lecture on diuretics, a session was designed to combine the PowerPoint and chalk talk approaches. Students created 10 concept diagrams following an instructor, who explained each step in the process using a document camera. For visual learners, these diagrams provided a layered representation of the information, gradually increasing in complexity. For learners with a preference for the reading learning style, the information was also available in corresponding PowerPoint slides. Scores from pre- and post-session quizzes indicated a high level of concept understanding and recall (median 1 [IQR 0 – 2] vs 4 [IQR 3 – 5]; p<0.001. The student perception survey data reported higher in-class attention levels (76%, an appreciation for the utility of self-created concept diagrams (88%, and a call for additional sessions being presented in this format (73%. Targeting a variety of student learning styles by using the active development of concept diagrams, in addition to traditional PowerPoint slides, can promote student engagement and enhance content understanding.   Type: Case Study

  6. RFA: R-Squared Fitting Analysis Model for Power Attack

    Directory of Open Access Journals (Sweden)

    An Wang

    2017-01-01

    Full Text Available Correlation Power Analysis (CPA introduced by Brier et al. in 2004 is an important method in the side-channel attack and it enables the attacker to use less cost to derive secret or private keys with efficiency over the last decade. In this paper, we propose R-squared fitting model analysis (RFA which is more appropriate for nonlinear correlation analysis. This model can also be applied to other side-channel methods such as second-order CPA and collision-correlation power attack. Our experiments show that the RFA-based attacks bring significant advantages in both time complexity and success rate.

  7. Analysis of Trinity Power Metrics for Automated Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Michalenko, Ashley Christine [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-07-28

    This is a presentation from Los Alamos National Laboraotyr (LANL) about the analysis of trinity power metrics for automated monitoring. The following topics are covered: current monitoring efforts, motivation for analysis, tools used, the methodology, work performed during the summer, and future work planned.

  8. Multiple perspective vulnerability analysis of the power network

    Science.gov (United States)

    Wang, Shuliang; Zhang, Jianhua; Duan, Na

    2018-02-01

    To understand the vulnerability of the power network from multiple perspectives, multi-angle and multi-dimensional vulnerability analysis as well as community based vulnerability analysis are proposed in this paper. Taking into account of central China power grid as an example, correlation analysis of different vulnerability models is discussed. Then, vulnerabilities produced by different vulnerability metrics under the given vulnerability models and failure scenarios are analyzed. At last, applying the community detecting approach, critical areas of central China power grid are identified, Vulnerable and robust communities on both topological and functional perspective are acquired and analyzed. The approach introduced in this paper can be used to help decision makers develop optimal protection strategies. It will be also useful to give a multiple vulnerability analysis of the other infrastructure systems.

  9. Converter Power Density Increase using Low Inductive Integrated DC-link Capacitor/Bus

    DEFF Research Database (Denmark)

    Trintis, Ionut; Franke, Toke; Rannested, Bjørn

    2015-01-01

    The power losses in switching devices have a direct effect on the maximum converter power. For a voltage source converter, the DC-link bus has a major influence on the power loss and safe operating area of the power devices. The Power Ring Film CapacitorTM integrated with an optimized bus structu...... has a measured inductance of around 5 nH. That allows the converter to switch with low turn-off losses, and allows the safe operation at higher dc-link voltages. This paper investigates the power transfer limits of a ShowerPower® cooled power stack....

  10. Small-scale wind power design, analysis, and environmental impacts

    CERN Document Server

    Abraham, John P

    2014-01-01

    In today's world, clean and robust energy sources are being sought to provide power to residences, commercial operations, and manufacturing enterprises. Among the most appealing energy sources is wind power-with its high reliability and low environmental impact. Wind power's rapid penetration into markets throughout the world has taken many forms, and this book discusses the types of wind power, as well as the appropriate decisions that need to be made regarding wind power design, testing, installation, and analysis. Inside, the authors detail the design of various small-wind systems including horizontal-axis wind turbines (HAWTs) and vertical-axis wind turbines (VAWTs). The design of wind turbines takes advantage of many avenues of investigation, all of which are included in the book. Analytical methods that have been developed over the past few decades are major methods used for design. Alternatively, experimentation (typically using scaled models in wind tunnels) and numerical simulation (using modern comp...

  11. THE MURCHISON WIDEFIELD ARRAY 21 cm POWER SPECTRUM ANALYSIS METHODOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Daniel C.; Beardsley, A. P.; Bowman, Judd D. [Arizona State University, School of Earth and Space Exploration, Tempe, AZ 85287 (United States); Hazelton, B. J.; Sullivan, I. S.; Barry, N.; Carroll, P. [University of Washington, Department of Physics, Seattle, WA 98195 (United States); Trott, C. M.; Pindor, B.; Briggs, F.; Gaensler, B. M. [ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) (Australia); Dillon, Joshua S.; Oliveira-Costa, A. de; Ewall-Wice, A.; Feng, L. [MIT Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States); Pober, J. C. [Brown University, Department of Physics, Providence, RI 02912 (United States); Bernardi, G. [Department of Physics and Electronics, Rhodes University, Grahamstown 6140 (South Africa); Cappallo, R. J.; Corey, B. E. [MIT Haystack Observatory, Westford, MA 01886 (United States); Emrich, D., E-mail: daniel.c.jacobs@asu.edu [International Centre for Radio Astronomy Research, Curtin University, Perth, WA 6845 (Australia); and others

    2016-07-10

    We present the 21 cm power spectrum analysis approach of the Murchison Widefield Array Epoch of Reionization project. In this paper, we compare the outputs of multiple pipelines for the purpose of validating statistical limits cosmological hydrogen at redshifts between 6 and 12. Multiple independent data calibration and reduction pipelines are used to make power spectrum limits on a fiducial night of data. Comparing the outputs of imaging and power spectrum stages highlights differences in calibration, foreground subtraction, and power spectrum calculation. The power spectra found using these different methods span a space defined by the various tradeoffs between speed, accuracy, and systematic control. Lessons learned from comparing the pipelines range from the algorithmic to the prosaically mundane; all demonstrate the many pitfalls of neglecting reproducibility. We briefly discuss the way these different methods attempt to handle the question of evaluating a significant detection in the presence of foregrounds.

  12. An artificial intelligence approach towards disturbance analysis in nuclear power plants

    International Nuclear Information System (INIS)

    Lindner, A.; Klebau, J.; Fielder, U.; Baldeweg, F.

    1987-01-01

    The scale and degree of sophistication of technological plants, e.g. nuclear power plants, have been essentially increased during the last decades. Conventional disturbance analysis systems have proved to work successfully in wellknown situations. But in cases of emergencies, the operator staff needs a more advanced assistance in realizing diagnosis and therapy control. The significance of introducing artificial intelligence methods in nuclear power technology is emphasized. Main features of the on-line disturbance analysis system SAAP-2 are reported about. It is being developed for application in nuclear power plants. 9 refs. (author)

  13. Exergy analysis of a gas turbine power plant | Oko | Journal of ...

    African Journals Online (AJOL)

    Exergy analysis of a 100MW gas turbine power plant that works on the. Brayton cycle is presented. The average increase in the thermodynamic degradation of the plant over the period of six (6) years at three different levels of load was assessed. The exergy analysis of the plant was done on two sets of data: one from the ...

  14. Single-phase power distribution system power flow and fault analysis

    Science.gov (United States)

    Halpin, S. M.; Grigsby, L. L.

    1992-01-01

    Alternative methods for power flow and fault analysis of single-phase distribution systems are presented. The algorithms for both power flow and fault analysis utilize a generalized approach to network modeling. The generalized admittance matrix, formed using elements of linear graph theory, is an accurate network model for all possible single-phase network configurations. Unlike the standard nodal admittance matrix formulation algorithms, the generalized approach uses generalized component models for the transmission line and transformer. The standard assumption of a common node voltage reference point is not required to construct the generalized admittance matrix. Therefore, truly accurate simulation results can be obtained for networks that cannot be modeled using traditional techniques.

  15. Fractal Characteristics Analysis of Blackouts in Interconnected Power Grid

    DEFF Research Database (Denmark)

    Wang, Feng; Li, Lijuan; Li, Canbing

    2018-01-01

    The power failure models are a key to understand the mechanism of large scale blackouts. In this letter, the similarity of blackouts in interconnected power grids (IPGs) and their sub-grids is discovered by the fractal characteristics analysis to simplify the failure models of the IPG. The distri......The power failure models are a key to understand the mechanism of large scale blackouts. In this letter, the similarity of blackouts in interconnected power grids (IPGs) and their sub-grids is discovered by the fractal characteristics analysis to simplify the failure models of the IPG....... The distribution characteristics of blackouts in various sub-grids are demonstrated based on the Kolmogorov-Smirnov (KS) test. The fractal dimensions (FDs) of the IPG and its sub-grids are then obtained by using the KS test and the maximum likelihood estimation (MLE). The blackouts data in China were used...

  16. International and Domestic Development Trends of Electromagnetic Transient Analysis Programs for Power Systems

    Science.gov (United States)

    Noda, Taku

    Nowadays, there is quite high demand for electromagnetic transient (EMT) analysis programs and real-time simulators for power systems. In addition to the conventional demand such as overvoltage, over-current and oscillation simulations, the new demand that includes simulations of power-electronics circuits and power quality is increasing. With this background, development groups of EMT programs and real-time simulators have made progress in terms of computational performance and user experience. In Japan, Central Research Institute of Electric Power Industry has newly developed an EMT analysis program called XTAP (eXpandable Transient Analysis Program). This article overviews these international and domestic development trends of EMT analysis programs and real-time simulators.

  17. A Novel Elliptic Curve Scalar Multiplication Algorithm against Power Analysis

    Directory of Open Access Journals (Sweden)

    Hongming Liu

    2013-01-01

    Full Text Available Nowadays, power analysis attacks are becoming more and more sophisticated. Through power analysis attacks, an attacker can obtain sensitive data stored in smart cards or other embedded devices more efficiently than with any other kind of physical attacks. Among power analysis, simple power analysis (SPA is probably the most effective against elliptic curve cryptosystem, because an attacker can easily distinguish between point addition and point doubling in a single execution of scalar multiplication. To make elliptic curve scalar multiplication secure against SPA attacks, many methods have been proposed using special point representations. In this paper, a simple but efficient SPA-resistant multiscalar multiplication is proposed. The method is to convert the scalar into a nonadjacent form (NAF representation at first and then constitute it in a new signed digit representation. This new representation is undertaken at a small precomputation cost, as each representation needs just one doubling and 1/2 additions for each bit. In addition, when combined with randomization techniques, the proposed method can also guard against differential power analysis (DPA attack.

  18. Harmonic Analysis and Active Filtering in Offshore Wind Power Plants

    DEFF Research Database (Denmark)

    Chaudhary, Sanjay Kumar; Freijedo Fernandez, Francisco Daniel; Guerrero, Josep M.

    2015-01-01

    Due to presence of long high voltage cable networks, and power transformers for the grid connection, the offshore wind power plants (OWPPs) are susceptible to harmonic distortion and resonances. The grid connection of OWPP should not cause the harmonic distortion beyond the permissible limits...... at the point of common coupling (PCC). The resonance conditions should be avoided in all cases. This paper describes the harmonic analysis techniques applied on an OWPP network model. A method is proposed to estimate the harmonic current compensation from a shunt-connected active power filter to mitigate...

  19. Caffeine Increases Work Done above Critical Power, but Not Anaerobic Work.

    Science.gov (United States)

    Silveira, Rodrigo; Andrade-Souza, Victor Amorim; Arcoverde, Lucyana; Tomazini, Fabiano; Sansonio, André; Bishop, David John; Bertuzzi, Romulo; Lima-Silva, Adriano Eduardo

    2018-01-01

    The assumption that the curvature constant (W') of the power-duration relationship represents anaerobic work capacity is a controversial, unresolved question. We investigated if caffeine ingestion could increase total work done above critical power (CP), and if this would be accompanied by greater anaerobic energy expenditure and by an enhanced maintenance of maximal oxidative metabolic rate. Nine men (26.6 ± 5.3 yr, V˙O2max 40.6 ± 5.8 mL·kg·min) cycled until exhaustion at different exercise intensities on different days to determine the CP and W'. On separated days, participants cycled until exhaustion in the severe-intensity domain (136% ± 7% of CP) after ingesting either caffeine (5 mg·kg body mass) or a placebo. Time to exhaustion was 34% longer with caffeine compared with placebo, and this was accompanied by a greater work done above CP (23.7 ± 5.7 vs 17.5 ± 3.6 kJ; 130% ± 30% vs 95% ± 14% of W', P Caffeine increased the aerobic energy expenditure (296.4 ± 91.0 vs 210.2 ± 71.9 kJ, P caffeine, but the V˙O2 end was similar between conditions and was not different from V˙O2max. Caffeine did not change time to reach V˙O2max but increased time maintained at V˙O2max (199.3 ± 105.9 vs 111.9 ± 87.1 s, P Caffeine increased total work done above CP, but this was not associated with greater anaerobic work. Rather, this was associated with a higher tolerance to maintain exercise at maximal oxidative metabolic rate.

  20. Risk analysis of geothermal power plants using Failure Modes and Effects Analysis (FMEA) technique

    International Nuclear Information System (INIS)

    Feili, Hamid Reza; Akar, Navid; Lotfizadeh, Hossein; Bairampour, Mohammad; Nasiri, Sina

    2013-01-01

    Highlights: • Using Failure Modes and Effects Analysis (FMEA) to find potential failures in geothermal power plants. • We considered 5 major parts of geothermal power plants for risk analysis. • Risk Priority Number (RPN) is calculated for all failure modes. • Corrective actions are recommended to eliminate or decrease the risk of failure modes. - Abstract: Renewable energy plays a key role in the transition toward a low carbon economy and the provision of a secure supply of energy. Geothermal energy is a versatile source as a form of renewable energy that meets popular demand. Since some Geothermal Power Plants (GPPs) face various failures, the requirement of a technique for team engineering to eliminate or decrease potential failures is considerable. Because no specific published record of considering an FMEA applied to GPPs with common failure modes have been found already, in this paper, the utilization of Failure Modes and Effects Analysis (FMEA) as a convenient technique for determining, classifying and analyzing common failures in typical GPPs is considered. As a result, an appropriate risk scoring of occurrence, detection and severity of failure modes and computing the Risk Priority Number (RPN) for detecting high potential failures is achieved. In order to expedite accuracy and ability to analyze the process, XFMEA software is utilized. Moreover, 5 major parts of a GPP is studied to propose a suitable approach for developing GPPs and increasing reliability by recommending corrective actions for each failure mode

  1. Summary of IEA-R1 research a reactor licensing related to its power increase from 2 to 10 MW

    International Nuclear Information System (INIS)

    1989-04-01

    This work is a summary of IEA-R1 research reactor licensing related to its power increase from 2 to 10 MW. It reports also safety requirements, fuel elements, and reactor control modifications inherent to power increase. (A.C.A.S.)

  2. Environmental cost/benefit analysis for fusion power plants

    International Nuclear Information System (INIS)

    Young, J.R.

    1976-11-01

    This document presents a cost/benefit analysis of use of fusion power plants early in the 21st century. The first section describes the general formulation of the analysis. Included are the selection of the alternatives to the fusion reactor, selection of the power system cases to be compared, and a general comparison of the environmental effects of the selected alternatives. The second section compares the cumulative environmental effects from 2010 to 2040 for the primary cases of the power system with and without fusion reactors. The third section briefly illustrates the potential economic benefits if fusion reactors produce electricity at a lower unit cost than LMFBRs can. The fourth section summarizes the cost/benefit analysis

  3. Determination of the potential for utilising combined heat and power and of the target reduction of CO{sub 2} emissions, inclusive of cost analysis (increased use of combined heat and power); Ermittlung der Potenziale fuer die Anwendung der Kraft-Waerme-Kopplung und der erzielbaren Minderung der CO{sub 2}-Emissionen einschliesslich Bewertung der Kosten (Verstaerkte Nutzung der Kraft-Waerme-Kopplung)

    Energy Technology Data Exchange (ETDEWEB)

    Horn, Manfred; Ziesing, Hans-Joachim [Deutsches Inst. fuer Wirtschaftsforschung, Berlin (Germany); Matthes, Felix Christian; Harthan, Ralph [Oeko Institut e.V., Berlin (Germany); Menzler, Gerald [VIK Verband der Industriellen Energie- und Kraftwirtschaft e.V., Essen (Germany)

    2007-07-15

    The report provides a statistical overview of CHP utilisation up to now in Germany, analyses the general economic and political conditions with a view to evaluating the competitiveness of CHP, discusses the effectiveness of the German CHP Act with respect to its contribution to meeting emissions-related goals, analyses the cost-effectiveness of investments in different types of new CHP installations, addresses mid- and longer term potential as well as impediments to the utilisation of CHP installations, presents model simulations of how CHP is expected to develop in the context of economic conditions subject to various general political conditions and makes recommendations with an eye to additional requirements and opportunities to support CHP, against the background of the findings of the analysis. (orig.)

  4. Development and analysis of a new integrated power and cooling ...

    Indian Academy of Sciences (India)

    Cooling needs are increasing rapidly at hot climatic countries with increased global warming. The existed vapour compression refrigeration (VCR) system demands electricity for its operation which is more expensive. The concept of a newly proposed cooling cogeneration cycle has been developed by clubbing the power ...

  5. Thermodynamic, energy efficiency, and power density analysis of reverse electrodialysis power generation with natural salinity gradients.

    Science.gov (United States)

    Yip, Ngai Yin; Vermaas, David A; Nijmeijer, Kitty; Elimelech, Menachem

    2014-05-06

    Reverse electrodialysis (RED) can harness the Gibbs free energy of mixing when fresh river water flows into the sea for sustainable power generation. In this study, we carry out a thermodynamic and energy efficiency analysis of RED power generation, and assess the membrane power density. First, we present a reversible thermodynamic model for RED and verify that the theoretical maximum extractable work in a reversible RED process is identical to the Gibbs free energy of mixing. Work extraction in an irreversible process with maximized power density using a constant-resistance load is then examined to assess the energy conversion efficiency and power density. With equal volumes of seawater and river water, energy conversion efficiency of ∼ 33-44% can be obtained in RED, while the rest is lost through dissipation in the internal resistance of the ion-exchange membrane stack. We show that imperfections in the selectivity of typical ion exchange membranes (namely, co-ion transport, osmosis, and electro-osmosis) can detrimentally lower efficiency by up to 26%, with co-ion leakage being the dominant effect. Further inspection of the power density profile during RED revealed inherent ineffectiveness toward the end of the process. By judicious early discontinuation of the controlled mixing process, the overall power density performance can be considerably enhanced by up to 7-fold, without significant compromise to the energy efficiency. Additionally, membrane resistance was found to be an important factor in determining the power densities attainable. Lastly, the performance of an RED stack was examined for different membrane conductivities and intermembrane distances simulating high performance membranes and stack design. By thoughtful selection of the operating parameters, an efficiency of ∼ 37% and an overall gross power density of 3.5 W/m(2) represent the maximum performance that can potentially be achieved in a seawater-river water RED system with low

  6. Evaluation of thermal power plant operational performance in Taiwan by data envelopment analysis

    International Nuclear Information System (INIS)

    Liu, C.H.; Lin, Sue J.; Lewis, Charles

    2010-01-01

    Electricity is essential in the economic development of a nation. Due to the rapid growth of economy and industrial development in Taiwan, the demand for use of electricity has increased rapidly. This study evaluates the power-generation efficiency of major thermal power plants in Taiwan during 2004-2006 using the data envelopment analysis (DEA) approach. A stability test was conducted to verify the stability of the DEA model. According to the results, all power plants studied achieved acceptable overall operational efficiencies during 2004-2006, and the combined cycle power plants were the most efficient among all plants. The most important variable in this DEA model is the 'heating value of total fuels'. Findings from this study can be beneficial in improving some of the existing power plants and for more efficient operational strategies and related policy-making for future power plants in Taiwan.

  7. Steady state load models for power system analysis

    OpenAIRE

    Cresswell, Charles

    2009-01-01

    The last full review of load models used for power system studies occurred in the 1980s. Since then, new types of loads have been introduced and system load mix has changed considerably. The examples of newly introduced loads include drive-controlled motors, low energy consumption light sources and other modern power electronic loads. Their numbers have been steadily increasing in recent years, a trend which is expected to escalate. Accordingly, the majority of load models used...

  8. PowerPlay: Training an Increasingly General Problem Solver by Continually Searching for the Simplest Still Unsolvable Problem.

    Science.gov (United States)

    Schmidhuber, Jürgen

    2013-01-01

    Most of computer science focuses on automatically solving given computational problems. I focus on automatically inventing or discovering problems in a way inspired by the playful behavior of animals and humans, to train a more and more general problem solver from scratch in an unsupervised fashion. Consider the infinite set of all computable descriptions of tasks with possibly computable solutions. Given a general problem-solving architecture, at any given time, the novel algorithmic framework PowerPlay (Schmidhuber, 2011) searches the space of possible pairs of new tasks and modifications of the current problem solver, until it finds a more powerful problem solver that provably solves all previously learned tasks plus the new one, while the unmodified predecessor does not. Newly invented tasks may require to achieve a wow-effect by making previously learned skills more efficient such that they require less time and space. New skills may (partially) re-use previously learned skills. The greedy search of typical PowerPlay variants uses time-optimal program search to order candidate pairs of tasks and solver modifications by their conditional computational (time and space) complexity, given the stored experience so far. The new task and its corresponding task-solving skill are those first found and validated. This biases the search toward pairs that can be described compactly and validated quickly. The computational costs of validating new tasks need not grow with task repertoire size. Standard problem solver architectures of personal computers or neural networks tend to generalize by solving numerous tasks outside the self-invented training set; PowerPlay's ongoing search for novelty keeps breaking the generalization abilities of its present solver. This is related to Gödel's sequence of increasingly powerful formal theories based on adding formerly unprovable statements to the axioms without affecting previously provable theorems. The continually increasing

  9. Practical application of the benchmarking technique to increase reliability and efficiency of power installations and main heat-mechanic equipment of thermal power plants

    Science.gov (United States)

    Rimov, A. A.; Chukanova, T. I.; Trofimov, Yu. V.

    2016-12-01

    Data on the comparative analysis variants of the quality of power installations (benchmarking) applied in the power industry is systematized. It is shown that the most efficient variant of implementation of the benchmarking technique is the analysis of statistical distributions of the indicators in the composed homogenous group of the uniform power installations. The benchmarking technique aimed at revealing the available reserves on improvement of the reliability and heat efficiency indicators of the power installations of the thermal power plants is developed in the furtherance of this approach. The technique provides a possibility of reliable comparison of the quality of the power installations in their homogenous group limited by the number and adoption of the adequate decision on improving some or other technical characteristics of this power installation. The technique provides structuring of the list of the comparison indicators and internal factors affecting them represented according to the requirements of the sectoral standards and taking into account the price formation characteristics in the Russian power industry. The mentioned structuring ensures traceability of the reasons of deviation of the internal influencing factors from the specified values. The starting point for further detail analysis of the delay of the certain power installation indicators from the best practice expressed in the specific money equivalent is positioning of this power installation on distribution of the key indicator being a convolution of the comparison indicators. The distribution of the key indicator is simulated by the Monte-Carlo method after receiving the actual distributions of the comparison indicators: specific lost profit due to the short supply of electric energy and short delivery of power, specific cost of losses due to the nonoptimal expenditures for repairs, and specific cost of excess fuel equivalent consumption. The quality loss indicators are developed

  10. Methods and tools for analysis and optimization of power plants

    Energy Technology Data Exchange (ETDEWEB)

    Assadi, Mohsen

    2000-09-01

    The most noticeable advantage of the introduction of the computer-aided tools in the field of power generation, has been the ability to study the plant's performance prior to the construction phase. The results of these studies have made it possible to change and adjust the plant layout to match the pre-defined requirements. Further development of computers in recent years has opened up for implementation of new features in the existing tools and also for the development of new tools for specific applications, like thermodynamic and economic optimization, prediction of the remaining component life time, and fault diagnostics, resulting in improvement of the plant's performance, availability and reliability. The most common tools for pre-design studies are heat and mass balance programs. Further thermodynamic and economic optimization of plant layouts, generated by the heat and mass balance programs, can be accomplished by using pinch programs, exergy analysis and thermoeconomics. Surveillance and fault diagnostics of existing systems can be performed by using tools like condition monitoring systems and artificial neural networks. The increased number of tools and their various construction and application areas make the choice of the most adequate tool for a certain application difficult. In this thesis the development of different categories of tools and techniques, and their application area are reviewed and presented. Case studies on both existing and theoretical power plant layouts have been performed using different commercially available tools to illuminate their advantages and shortcomings. The development of power plant technology and the requirements for new tools and measurement systems have been briefly reviewed. This thesis contains also programming techniques and calculation methods concerning part-load calculations using local linearization, which has been implemented in an inhouse heat and mass balance program developed by the author

  11. Introduction of low-temperature swirl technology of burning as a way of increase in ecological of low power boilers

    Science.gov (United States)

    Trinchenko, A. A.; Paramonov, A. P.

    2017-10-01

    Work is devoted to the solution of problems of energy efficiency increase in low power boilers at combustion of solid fuel. The technological method of nitrogen oxides decomposition on a surface of carbon particles with education environmentally friendly carbonic acid and molecular nitrogen is considered during the work of a low-temperature swirl fire chamber. Based on the analysis of physical and chemical processes of a fuel chemically connected energy transition into thermal, using the diffusive and kinetic theory of burning modern approaches the technique, mathematical model and the settlement program for assessment of plant ecological indicators when using a new method are developed. Alternative calculations of furnace process are carried out, quantitative assessment of nitrogen oxides emissions level of the reconstructed boiler is executed. The results of modeling and experimental data have approved that the organization of swirl burning increases overall performance of a fire chamber and considerably reduces emissions of nitrogen oxides.

  12. Modeling and analysis of harmonic resonance in a power electronics based AC power system

    DEFF Research Database (Denmark)

    Wang, Xiongfei; Blaabjerg, Frede; Chen, Zhe

    2013-01-01

    -based analysis approach is adopted and expanded to a meshed and balanced three-phase power network. An impedance ratio derivation method is proposed based on the nodal admittance matrix. By this means, the contribution of each inverter to the system resonance modes can be easily predicted by the Nyquist...

  13. 76 FR 16394 - Analysis of Horizontal Market Power Under the Federal Power Act

    Science.gov (United States)

    2011-03-23

    ... to be present at lower market shares in markets for commodities with low demand price- responsiveness, like electricity, than in markets with high demand elasticity.\\18\\ \\15\\ AEP Power Marketing, Inc., 97... identified customer (includes a delivered price test (DPT) analysis, consideration of transmission capability...

  14. Approaches and methods for econometric analysis of market power

    DEFF Research Database (Denmark)

    Perekhozhuk, Oleksandr; Glauben, Thomas; Grings, Michael

    2017-01-01

    This study discusses two widely used approaches in the New Empirical Industrial Organization (NEIO) literature and examines the strengths and weaknesses of the Production-Theoretic Approach (PTA) and the General Identification Method (GIM) for the econometric analysis of market power in agricultu......This study discusses two widely used approaches in the New Empirical Industrial Organization (NEIO) literature and examines the strengths and weaknesses of the Production-Theoretic Approach (PTA) and the General Identification Method (GIM) for the econometric analysis of market power...

  15. Analysis and experimental evaluation of shunt active power filter for power quality improvement based on predictive direct power control.

    Science.gov (United States)

    Aissa, Oualid; Moulahoum, Samir; Colak, Ilhami; Babes, Badreddine; Kabache, Nadir

    2017-10-12

    This paper discusses the use of the concept of classical and predictive direct power control for shunt active power filter function. These strategies are used to improve the active power filter performance by compensation of the reactive power and the elimination of the harmonic currents drawn by non-linear loads. A theoretical analysis followed by a simulation using MATLAB/Simulink software for the studied techniques has been established. Moreover, two test benches have been carried out using the dSPACE card 1104 for the classic and predictive DPC control to evaluate the studied methods in real time. Obtained results are presented and compared in this paper to confirm the superiority of the predictive technique. To overcome the pollution problems caused by the consumption of fossil fuels, renewable energies are the alternatives recommended to ensure green energy. In the same context, the tested predictive filter can easily be supplied by a renewable energy source that will give its impact to enhance the power quality.

  16. 5-week block periodization increases aerobic power in elite cross-country skiers.

    Science.gov (United States)

    Rønnestad, B R; Hansen, J; Thyli, V; Bakken, T A; Sandbakk, Ø

    2016-02-01

    The purpose of this study was to compare the effect of two different methods of organizing endurance training in elite cross-country skiers approaching the competition period. During the 5-week intervention period, one group performed block periodization (BP; n = 10) with 5 and 3 high-intensity sessions (HIT) during the first and third training week. One HIT was performed during the remaining weeks in BP, while the group performing traditional training organization (TRAD, n = 9) performed two weekly HIT except during the third week where they performed three HIT. HIT were interspersed with low-intensity training (LIT) and both groups performed similar total amount of both HIT and LIT during the intervention. BP achieved a larger relative increase in peak power output and power output at a blood lactate concentration of 4 mmol/L than TRAD (4 ± 4 vs -3 ± 6% and 11 ± 10 vs 2 ± 4%, respectively, both P block periodization of endurance training have superior effects on several endurance and performance indices compared with traditional organization. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Safety analysis on CANDU-6 nuclear power plant: changes in thermal hydraulic operational conditions concerning regional over power trip setpoints

    International Nuclear Information System (INIS)

    Lee, Jae Yong; Kim, Yong Bae; Kim, Jong Hyun; Son, Hyung Min

    2009-01-01

    A CANDU-6 nuclear power plant has the variable of regional overpower trip (ROPT) to prevent regional overpower within the reactor core. ROPT setpoints are calculated on the basis of channel power where dryout starts to take place in each nuclear fuel channel (i.e. critical channel power; CCP), which is determined based on various core-physical configurations and thermal hydraulic boundary conditions that may be generated throughout the entire life of a nuclear reactor. Variables included in the thermal hydraulic boundary condition (i.e. temperature of the inlet header, pressure on the outlet header, and differential pressure between inlet and outlet headers) change gradually as the number of operational years increases. As for these three operational variables, their operational constraints in consideration of reactor safety are suggested in the operational technical specifications for nuclear power plants. This paper first uses NUCIRC, a code for analyzing thermal hydraulic power at the core of heavy water nuclear reactor, to examine the impacts of changes in these thermal hydraulic boundary condition variables on CCP. To analyze the impacts of changes in the variables for thermal hydraulic boundary conditions on the safety of nuclear reactors, safety analysis is then performed on three representative types of design basis accidents in heavy water reactors-small break loss of coolant accident (SBLOCA), loss of regulations (LOR), and loss of forced circulation-using CATHENA, a thermal hydraulic safety analysis code. By performing two types of thermal hydraulic analysis, the following additional operational margins are ensured against the current operating limits: +2.1 .deg. C for the temperature of the reactor inlet header; -60kPa for differential pressure between inlet and outlet headers; and -40kPa for pressure on the reactor outlet header. By revising the operating limits on this basis, it will be possible to prevent possible reactor power cutbacks caused by

  18. Ways to increase efficiency of the HTGR coupled with the gas-turbine power conversion unit - HTR2008-58274

    International Nuclear Information System (INIS)

    Golovko, V. F.; Kodochigov, N. G.; Vasyaev, A. V.; Shenoy, A.; Baxi, C. B.

    2008-01-01

    reactor plants with highly recuperative steam cycle with supercritical heat parameters, the net efficiency of electricity generation reaches 50-55%. There are three methods of Brayton cycle carnotization: regeneration, helium cooldown during compression, and heat supply during expansion. These methods can be used both separately and in combination, which gives a total of seven complex heat flow diagrams. Besides, there are ways to increase helium temperature at the reactor inlet and outlet, to reduce hydraulic losses in the helium path, to increase the turbomachine (TM) rotation speed in order to improve the turbine and compressor efficiency, to reduce helium leaks in the circulation path, etc. The analysis of GT-MHR, PBMR and GTHTR-300 development experience allows identification of the main ways of increasing the efficiency by selecting optimal parameters and design solutions for the reactor and power conversion unit. The paper estimates the probability of reaching the maximum electricity generation efficiency in reactor plants with the HTGR and gas turbine cycle with account of the up-to-date development status of major reactor plant components (reactor, vessels, turbo-compressor (TC), generator, heat exchange equipment, and structural materials). (authors)

  19. A wirelessly-powered homecage with animal behavior analysis and closed-loop power control.

    Science.gov (United States)

    Yaoyao Jia; Zheyuan Wang; Canales, Daniel; Tinkler, Morgan; Chia-Chun Hsu; Madsen, Teresa E; Mirbozorgi, S Abdollah; Rainnie, Donald; Ghovanloo, Maysam

    2016-08-01

    This paper presents a new EnerCage-homecage system, EnerCage-HC2, for longitudinal electrophysiology data acquisition experiments on small freely moving animal subjects, such as rodents. EnerCage-HC2 is equipped with multi-coil wireless power transmission (WPT), closed-loop power control, bidirectional data communication via Bluetooth Low Energy (BLE), and Microsoft Kinect® based animal behavior tracking and analysis. The EnerCage-HC2 achieves a homogeneous power transfer efficiency (PTE) of 14% on average, with ~42 mW power delivered to the load (PDL) at a nominal height of 7 cm by the closed-loop power control mechanism. The Microsoft Kinect® behavioral analysis algorithm can not only track the animal position in real-time but also classify 5 different types of rodent behaviors: standstill, walking, grooming, rearing, and rotating. A proof-of-concept in vivo experiment was conducted on two awake freely behaving rats while successfully operating a one-channel stimulator and generating an ethogram.

  20. Thermodynamic analysis of thermal efficiency and power of Minto engine

    International Nuclear Information System (INIS)

    He, Wei; Hou, Jingxin; Zhang, Yang; Ji, Jie

    2011-01-01

    Minto engine is a kind of liquid piston heat engine that operates on a small temperature gradient. But there is no power formula for it yet. And its thermal efficiency is low and formula sometimes is misused. In this paper, deriving the power formula and simplifying the thermal efficiency formula of Minto engine based on energy distribution analysis will be discussed. To improve the original Minto engine, a new design of improved Minto engine is proposed and thermal efficiency formula and power formula are also given. A computer program was developed to analyze thermal efficiency and power of original and improved Minto engines operating between low and high-temperature heat sources. The simulation results show that thermal efficiency of improved Minto engine can reach over 7% between 293.15 K and 353.15 K which is much higher than that of original one; the temperature difference between upper and lower containers is lower than half of that between low and high temperature of heat sources when the original Minto engines output the maximum power; on the contrary, it is higher in the improved Minto engines. -- Highlights: ► The thermal efficiency formula of Minto engine is simplified and the power formula is established. ► A high-powered design of improved Minto engine is proposed. ► A computer simulation program based on real operating environment is developed.

  1. Economic analysis to compare fabrication of nuclear power and fossil fuel power plants at Iran

    International Nuclear Information System (INIS)

    Rasouliye Koohi, Mojtaba

    1997-01-01

    Electric power due to its many advantages over other forms of energies covers most of the world's energy demands.The electric power can be produced by various energy converting systems fed by different energy resources like fossil fuels, nuclear, hydro and renewable energies, each having their own appropriate technologies. The fossil fuel not only consumes the deplete and precious sources of non conventional energies but they add pollution to environment too. The nuclear power plants has its own share of radioactive pollutions which, of course can be controlled by taking precautionary measures. The investing cost of each generated unit (KWh) in the nuclear power plants, comparing with its equivalent production by fossil fuels is investigated. The various issues of economical analysis, technical, political and environmental are the different aspects, which individually can influence the decisions for kind of power plant to be installed. Finally, it is concluded that the fossil and nuclear power generations both has its own advantages and disadvantages. Hence, from a specializing point of view, it may not be proper to prefer one over the others

  2. Increasing input power dynamic range of SOA by shifting the transparent wavelength of tunable optical filter

    DEFF Research Database (Denmark)

    Yu, Jianjun; Jeppesen, Palle

    2001-01-01

    Gain-saturation-induced self-phase modulation (SPM) leading to pulse distortion in a semiconductor optical amplifier (SOA) is overcome by shifting a tunable optical filter (TOF). A recovered or broadened pulse can be obtained after filtering the amplified pulse in the SOA even if the short pulse...... to a longer wavelength for RZ signals and to a shorter for NRZ signals. 80-Gb/s optical time division multiplexing (OTDM) signal amplification in the SOA is demonstrated for the first time. We also demonstrate that a large IPDR for the 80-Gb/s OTDM signal can be obtained by shifting the TOF....... is only 2-3 ps long. The input power dynamic range (IPDR) can be strongly increased by shifting the TOF and the direction of the shifted transparent wavelength is different for 10 Gb/s return-to-zero (RZ) or nonreturn-to-zero (NRZ) signals. The transparent wavelength of the TOF should be shifted...

  3. Method of increasing power within an optical cavity with long path lengths

    Energy Technology Data Exchange (ETDEWEB)

    Leen, John Brian; Bramall, Nathan E.

    2018-03-13

    A cavity-enhanced absorption spectroscopy instrument has an optical cavity with two or more cavity mirrors, one mirror of which having a hole or other aperture for injecting a light beam, and the same or another mirror of which being partially transmissive to allow exit of light to a detector. A spherical-spherical configuration with at least one astigmatic mirror or a spherical-cylindrical configuration where the spherical mirror could also be astigmatic prevents a reentrant condition wherein the injected beam would prematurely exit the cavity through the aperture. This combination substantially increases the number of passes of the injected beam through a sample volume for sensitive detection of chemical species even in less than ideal conditions including low power laser or LED sources, poor mirror reflectivity or detector noise at the wavelengths of interest, or cavity alignment issues such as vibration or temperature and pressure changes.

  4. Global analysis of a renewable micro hydro power generation plant

    Science.gov (United States)

    Rahman, Md. Shad; Nabil, Imtiaz Muhammed; Alam, M. Mahbubul

    2017-12-01

    Hydroelectric power or Hydropower means the power generated by the help of flowing water with force. It is one the best source of renewable energy in the world. Water evaporates from the earth's surface, forms clouds, precipitates back to earth, and flows toward the ocean. Hydropower is considered a renewable energy resource because it uses the earth's water cycle to generate electricity. As far as Global is concerned, only a small fraction of electricity is generated by hydro-power. The aim of our analysis is to demonstrate and observe the hydropower of the Globe in micro-scale by our experimental setup which is completely new in concept. This paper consists of all the Global and National Scenario of Hydropower. And how we can more emphasize the generation of Hydroelectric power worldwide.

  5. PyPSA: Python for Power System Analysis

    Directory of Open Access Journals (Sweden)

    Thomas Brown

    2018-01-01

    Full Text Available Python for Power System Analysis (PyPSA is a free software toolbox for simulating and optimising modern electrical power systems over multiple periods. PyPSA includes models for conventional generators with unit commitment, variable renewable generation, storage units, coupling to other energy sectors, and mixed alternating and direct current networks. It is designed to be easily extensible and to scale well with large networks and long time series. In this paper the basic functionality of PyPSA is described, including the formulation of the full power flow equations and the multi-period optimisation of operation and investment with linear power flow equations. PyPSA is positioned in the existing free software landscape as a bridge between traditional power flow analysis tools for steady-state analysis and full multi-period energy system models. The functionality is demonstrated on two open datasets of the transmission system in Germany (based on SciGRID and Europe (based on GridKit.   Funding statement: This research was conducted as part of the CoNDyNet project, which is supported by the German Federal Ministry of Education and Research under grant no. 03SF0472C. The responsibility for the contents lies solely with the authors

  6. Locality-Driven Parallel Static Analysis for Power Delivery Networks

    KAUST Repository

    Zeng, Zhiyu

    2011-06-01

    Large VLSI on-chip Power Delivery Networks (PDNs) are challenging to analyze due to the sheer network complexity. In this article, a novel parallel partitioning-based PDN analysis approach is presented. We use the boundary circuit responses of each partition to divide the full grid simulation problem into a set of independent subgrid simulation problems. Instead of solving exact boundary circuit responses, a more efficient scheme is proposed to provide near-exact approximation to the boundary circuit responses by exploiting the spatial locality of the flip-chip-type power grids. This scheme is also used in a block-based iterative error reduction process to achieve fast convergence. Detailed computational cost analysis and performance modeling is carried out to determine the optimal (or near-optimal) number of partitions for parallel implementation. Through the analysis of several large power grids, the proposed approach is shown to have excellent parallel efficiency, fast convergence, and favorable scalability. Our approach can solve a 16-million-node power grid in 18 seconds on an IBM p5-575 processing node with 16 Power5+ processors, which is 18.8X faster than a state-of-the-art direct solver. © 2011 ACM.

  7. Increased rate of force development during periodized maximum strength and power training is highly individual.

    Science.gov (United States)

    Peltonen, Heikki; Walker, Simon; Hackney, Anthony C; Avela, Janne; Häkkinen, Keijo

    2018-03-06

    Maximum strength training induces various improvements in the rate of force development (RFD) on a group level, but no study has investigated inter-individual adaptations in RFD. Fourteen men (28 ± 6 years old) performed the same 10-week maximum strength and then a 10-week power training program. Maximal force and RFD were recorded during maximal isometric leg extension voluntary contractions repeatedly before every 7th training session (2 sessions/week). After the intervention, subjects were retrospectively divided into three groups based on their RFD improvements: (1) improved only during the maximum strength period (MS-responders, + 100 ± 35%), (2) improved only during the power period (P-responders, + 53 ± 27%) or (3) no improvement at all (non-responders, + 3 ± 9%). All groups increased dynamic 1RM equally, but baseline 1RM was greater (p strength training period. MS-responders increased vastus lateralis cross-sectional area (+ 12 ± 9%, p strength period decreased testosterone (- 17 ± 12; 17 ± 22%), FAI ratio (- 12 ± 14; - 21 ± 23%) and testosterone/cortisol ratio (- 17 ± 25; - 31 ± 20%) in MS and P-responders, respectively. During the P-period hormonal levels plateaued. To conclude, periodized strength training induced different inter-individual physiological responses, and thus RFD development may vary between individuals. Therefore, RFD seems to be a useful tool for planning and monitoring strength training programs for individual neuromuscular performance needs.

  8. Increasing average power in medical ultrasonic endoscope imaging system by coded excitation

    Science.gov (United States)

    Chen, Xiaodong; Zhou, Hao; Wen, Shijie; Yu, Daoyin

    2008-12-01

    Medical ultrasonic endoscope is the combination of electronic endoscope and ultrasonic sensor technology. Ultrasonic endoscope sends the ultrasonic probe into coelom through biopsy channel of electronic endoscope and rotates it by a micro pre-motor, which requires that the length of ultrasonic probe is no more than 14mm and the diameter is no more than 2.2mm. As a result, the ultrasonic excitation power is very low and it is difficult to obtain a sharp image. In order to increase the energy and SNR of ultrasonic signal, we introduce coded excitation into the ultrasonic imaging system, which is widely used in radar system. Coded excitation uses a long coded pulse to drive ultrasonic transducer, which can increase the average transmitting power accordingly. In this paper, in order to avoid the overlapping between adjacent echo, we used a four-figure Barker code to drive the ultrasonic transducer, which is modulated at the operating frequency of transducer to improve the emission efficiency. The implementation of coded excitation is closely associated with the transient operating characteristic of ultrasonic transducer. In this paper, the transient operating characteristic of ultrasonic transducer excited by a shock pulse δ(t) is firstly analyzed, and then the exciting pulse generated by special ultrasonic transmitting circuit composing of MD1211 and TC6320. In the final part of the paper, we designed an experiment to validate the coded excitation with transducer operating at 5MHz and a glass filled with ultrasonic coupling liquid as the object. Driven by a FPGA, the ultrasonic transmitting circuit output a four-figure Barker excitation pulse modulated at 5MHz, +/-20 voltage and is consistent with the transient operating characteristic of ultrasonic transducer after matched by matching circuit. The reflected echo from glass possesses coded character, which is identical with the simulating result by Matlab. Furthermore, the signal's amplitude is higher.

  9. Increased mortality rate and suicide in Swedish former elite male athletes in power sports.

    Science.gov (United States)

    Lindqvist, A-S; Moberg, T; Ehrnborg, C; Eriksson, B O; Fahlke, C; Rosén, T

    2014-12-01

    Physical training has been shown to reduce mortality in normal subjects, and athletes have a healthier lifestyle after their active career as compared with normal subjects. Since the 1950s, the use of anabolic androgenic steroids (AAS) has been frequent, especially in power sports. The aim of the present study was to investigate mortality, including causes of death, in former Swedish male elite athletes, active 1960-1979, in wrestling, powerlifting, Olympic lifting, and the throwing events in track and field when the suspicion of former AAS use was high. Results indicate that, during the age period of 20-50 years, there was an excess mortality of around 45%. However, when analyzing the total study period, the mortality was not increased. Mortality from suicide was increased 2-4 times among the former athletes during the period of 30-50 years of age compared with the general population of men. Mortality rate from malignancy was lower among the athletes. As the use of AAS was marked between 1960 and 1979 and was not doping-listed until 1975, it seems probable that the effect of AAS use might play a part in the observed increased mortality and suicide rate. The otherwise healthy lifestyle among the athletes might explain the low malignancy rates. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Power Loss Analysis for Wind Power Grid Integration Based on Weibull Distribution

    Directory of Open Access Journals (Sweden)

    Ahmed Al Ameri

    2017-04-01

    Full Text Available The growth of electrical demand increases the need of renewable energy sources, such as wind energy, to meet that need. Electrical power losses are an important factor when wind farm location and size are selected. The capitalized cost of constant power losses during the life of a wind farm will continue to high levels. During the operation period, a method to determine if the losses meet the requirements of the design is significantly needed. This article presents a Simulink simulation of wind farm integration into the grid; the aim is to achieve a better understanding of wind variation impact on grid losses. The real power losses are set as a function of the annual variation, considering a Weibull distribution. An analytical method has been used to select the size and placement of a wind farm, taking into account active power loss reduction. It proposes a fast linear model estimation to find the optimal capacity of a wind farm based on DC power flow and graph theory. The results show that the analytical approach is capable of predicting the optimal size and location of wind turbines. Furthermore, it revealed that the annual variation of wind speed could have a strong effect on real power loss calculations. In addition to helping to improve utility efficiency, the proposed method can develop specific designs to speeding up integration of wind farms into grids.

  11. Exergy costing analysis and performance evaluation of selected gas turbine power plants

    OpenAIRE

    S.O. Oyedepo; R.O. Fagbenle; S.S. Adefila; Md.Mahbub Alam

    2015-01-01

    In this study, exergy costing analysis and performance evaluation of selected gas turbine power plants in Nigeria are carried out. The results of exergy analysis confirmed that the combustion chamber is the most exergy destructive component compared to other cycle components. The exergetic efficiency of the plants was found to depend significantly on a change in gas turbine inlet temperature (GTIT). The increase in exergetic efficiency with the increase in turbine inlet temperature is limited...

  12. Analysis of Dynamic Differential Swing Limited Logic for Low-Power Secure Applications

    Directory of Open Access Journals (Sweden)

    Denis Flandre

    2012-03-01

    Full Text Available Low-power secure applications such as Radio Frequency IDentification (RFID and smart cards represent extremely constrained environments in terms of power consumption and die area. This paper investigates the power, delay and security performances of the dynamic differential swing limited logic (DDSLL. A complete analysis of an advanced encryption standard (AES S-box is conducted using a low-power (LP 65 nm CMOS technology node. Measurements show that the DDSLL S-box has 35% less power consumption than the static CMOS S-box, with an area increase of only 12%, at the expense of a 2.5× increase in delay which remains fairly acceptable for low-power applications such as RFIDs and smart cards. Also when compared to other dynamic differential logic (DDL styles, simulation results show that DDSLL and dynamic current mode logic (DyCML consume the same power which is about 1.8× less that of sense amplifier based logic (SABL. The effect of process variations is also studied, measurement results show that the DDSLL style has lower variability in terms of dynamic power as the activity factor (αF is deterministic thanks to glitch-free operation. As for security, the perceived information metric demonstrates that the DDSLL S-box has a 3× security margin compared to static CMOS. Therefore, DDSLL presents an interesting tradeoff between improved security and area constrained low-power designs.

  13. Analysis of reactor power oscillation based on nonlinear dynamic theory

    International Nuclear Information System (INIS)

    Suzudo, Tomoaki

    1994-07-01

    Reactor power oscillations are discussed based on nonlinear dynamic theory with reference to stability problem of boiling water reactors (BWRs). The reactor noise from an actual plant is, firstly, analyzed by a method originally used for the analysis of chaotic phenomenon. The results show that this method gives better dynamic descriptor of oscillatory motion than those from previous methods, and that it is applicable to real-time monitoring system of the reactor core. Next, the low-dimensional phenomenological model of BWR power oscillation is analytically studied using bifurcation theory, a branch of nonlinear dynamic theory. From this analysis are derived explicit expressions for the steady state's linear stability and weak stability not given by numerical analyses, and the qualitative properties of the power oscillation can be better understood. (author)

  14. Improving packaging and increasing the level of integration in power electronics

    NARCIS (Netherlands)

    Popovic, J.

    2005-01-01

    The use of power electronics is growing extensively in applications such as the automotive field, lighting, power supplies, motor drives, etc. The ultimate goal is to make power electronics as transparent to the final user as possible, which means little extra cost, use of existing space and little

  15. Incorporation of a Wind Generator Model into a Dynamic Power Flow Analysis

    Directory of Open Access Journals (Sweden)

    Angeles-Camacho C.

    2011-07-01

    Full Text Available Wind energy is nowadays one of the most cost-effective and practical options for electric generation from renewable resources. However, increased penetration of wind generation causes the power networks to be more depend on, and vulnerable to, the varying wind speed. Modeling is a tool which can provide valuable information about the interaction between wind farms and the power network to which they are connected. This paper develops a realistic characterization of a wind generator. The wind generator model is incorporated into an algorithm to investigate its contribution to the stability of the power network in the time domain. The tool obtained is termed dynamic power flow. The wind generator model takes on account the wind speed and the reactive power consumption by induction generators. Dynamic power flow analysis is carried-out using real wind data at 10-minute time intervals collected for one meteorological station. The generation injected at one point into the network provides active power locally and is found to reduce global power losses. However, the power supplied is time-varying and causes fluctuations in voltage magnitude and power fl ows in transmission lines.

  16. Subsidence analysis Forsmark nuclear power plant - unit 1

    International Nuclear Information System (INIS)

    Bono, Nancy; Fredriksson, Anders; Maersk Hansen, Lars

    2010-12-01

    On behalf of SKB, Golder Associates Ltd carried out a risk analysis of subsidence during Forsmark nuclear power plant in the construction of the final repository for spent nuclear fuel near and below existing reactors. Specifically, the effect of horizontal cracks have been studied

  17. PRICE DISCRIMINATION AND MARKET POWER: A THEORETICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Olga Smirnova

    2015-07-01

    Full Text Available This paper analyzes the contemporary theoretical and empirical research in the field of impact assessment of market power and conclusions about the possibilities of the company to implement price discrimination in different market structures. The results of the analysis allow to evaluate current approaches to antitrust regulation of price discrimination.

  18. statistical analysis of wind speed for electrical power generation

    African Journals Online (AJOL)

    HOD

    Keywords: Wind speed - probability - density function – wind energy conversion system- statistical analyses. 1. INTRODUCTION. In order ..... "Statistical analysis of wind speed distribution based on six Weibull Methods for wind power evaluation in. Garoua, Cameroon," Revue des Energies. Renouvelables, vol. 18, no. 1, pp.

  19. 384 Power plant waste water sampling and analysis plan

    International Nuclear Information System (INIS)

    Hagerty, K.J.; Knotek, H.M.

    1995-01-01

    This document presents the 384 Power House Sampling and Analysis Plan. The Plan describes sampling methods, locations, frequency, analytes, and stream descriptions. The effluent streams from 384, were characterized in 1989, in support of the Stream Specific Report (WHC-EP-0342, Addendum 1)

  20. A Computer Program for Short Circuit Analysis of Electric Power ...

    African Journals Online (AJOL)

    This paper described the mathematical basis and computational framework of a computer program developed for short circuit studies of electric power systems. The Short Circuit Analysis Program (SCAP) is to be used to assess the composite effects of unbalanced and balanced faults on the overall reliability of electric ...

  1. Design and Thermal Analysis of a Solar Powered Cold Storage ...

    African Journals Online (AJOL)

    Design and Thermal Analysis of a Solar Powered Cold Storage Ware-House Using a Phase- Change Material. ... of Nigeria of perishable agricultural products at different conservation temperatures corresponding to the solidification temperatures of phase change materials using cheap and abundant source of energy.

  2. The Analysis of The Fault of Electrical Power Steering

    Directory of Open Access Journals (Sweden)

    Zhang Li Wen

    2016-01-01

    Full Text Available This paper analysis the common fault types of primary Electrical Power Steering system, meanwhile classify every fault. It provides the basis for further troubleshooting and maintenance. At the same time this paper propose a practical working principle of fault-tolerant, in order to make the EPS system more security and durability.

  3. 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

  4. Long Term Analysis of Adaptive Low-Power Instrument Platform Power and Battery Performance

    Science.gov (United States)

    Edwards, T.; Bowman, J. R.; Clauer, C. R.

    2017-12-01

    Operation of the Autonomous Adaptive Low-Power Instrument Platform (AAL-PIP) by the Magnetosphere-Ionosphere Science Team (MIST) at Virginia Tech has been ongoing for about 10 years. These instrument platforms are deployed on the East Antarctic Plateau in remote locations that are difficult to access regularly. The systems have been designed to operate unattended for at least 5 years. During the Austral summer, the systems charge batteries using solar panels and power is provided by the batteries during the winter months. If the voltage goes below a critical level, the systems go into hibernation and wait for voltage from the solar panels to initiate a restart sequence to begin operation and battery charging. Our first system was deployed on the East Antarctic Plateau in 2008 and we report here on an analysis of the power and battery performance over multiple years and provide an estimate for how long these systems can operate before major battery maintenance must be performed.

  5. Solar Dynamic Power System Stability Analysis and Control

    Science.gov (United States)

    Momoh, James A.; Wang, Yanchun

    1996-01-01

    The objective of this research is to conduct dynamic analysis, control design, and control performance test of solar power system. Solar power system consists of generation system and distribution network system. A bench mark system is used in this research, which includes a generator with excitation system and governor, an ac/dc converter, six DDCU's and forty-eight loads. A detailed model is used for modeling generator. Excitation system is represented by a third order model. DDCU is represented by a seventh order system. The load is modeled by the combination of constant power and constant impedance. Eigen-analysis and eigen-sensitivity analysis are used for system dynamic analysis. The effects of excitation system, governor, ac/dc converter control, and the type of load on system stability are discussed. In order to improve system transient stability, nonlinear ac/dc converter control is introduced. The direct linearization method is used for control design. The dynamic analysis results show that these controls affect system stability in different ways. The parameter coordination of controllers are recommended based on the dynamic analysis. It is concluded from the present studies that system stability is improved by the coordination of control parameters and the nonlinear ac/dc converter control stabilize system oscillation caused by the load change and system fault efficiently.

  6. TradeWind Deliverable 5.1: Effects of increasing wind power penetration on the power flows in European grids

    DEFF Research Database (Denmark)

    Lemström, Bettina; Uski-Joutsenvuo, Sanna; Holttinen, Hannele

    2008-01-01

    -border transmission. Risø has written section 4.2 about the impact of prediction errors of wind power production. VTT has carried out the model evaluation described in Chapter 3. Furthermore VTT has analysed the wind speed data, studied the moving weather effects and the capacity factor method presented in section 2...... flow simulations with a grid and market model developed in TradeWind Work Package 3, led by Sintef Energy Research. VTT, Sintef Energy Research and Risø have carried out the simulations of the different scenarios, analysed the results and written Chapter 4 about the impact of wind power on cross.......1, Chapter 5 and section 6.1, respectively. dena has made the calculations with the probabilistic method and written section 6.2....

  7. HIIT produces increases in muscle power and free testosterone in male masters athletes.

    Science.gov (United States)

    Herbert, P; Hayes, L D; Sculthorpe, N F; Grace, F M

    2017-10-01

    High-intensity interval training (HIIT) improves peak power output (PPO) in sedentary aging men but has not been examined in masters endurance athletes. Therefore, we investigated whether a six-week program of low-volume HIIT would (i) improve PPO in masters athletes and (ii) whether any change in PPO would be associated with steroid hormone perturbations. Seventeen male masters athletes (60 ± 5 years) completed the intervention, which comprised nine HIIT sessions over six weeks. HIIT sessions involved six 30-s sprints at 40% PPO, interspersed with 3 min active recovery. Absolute PPO (799 ± 205 W and 865 ± 211 W) and relative PPO (10.2 ± 2.0 W/kg and 11.0 ± 2.2 W/kg) increased from pre- to post-HIIT respectively ( P  athletes and increases free testosterone. Taken together, these data indicate there is a place for carefully timed HIIT epochs in regimes of masters athletes. © 2017 The authors.

  8. Kysat-2 electrical power system design and analysis

    Science.gov (United States)

    Molton, Brandon L.

    In 2012, Kentucky Space, LLC was offered the opportunity to design KYSat-2, a CubeSat mission which utilizes an experimental stellar-tracking camera system to test its effectiveness of determining the spacecraft's attitude while on orbit. Kentucky Space contracted Morehead State University to design the electrical power system (EPS) which will handle all power generation and power management and distribution to each of the KYSat-2 subsystems, including the flight computer, communications systems, and the experimental payload itself. This decision came as a result of the success of Morehead State's previous CubeSat mission, CXBN, which utilized a custom built power system and successfully launched in 2011. For the KYSat-2 EPS to be successful, it was important to design a system which was efficient enough to handle the power limitations of the space environment and robust enough to handle the challenges of powering a spacecraft on orbit. The system must be developed with a positive power budget, generating and storing more power than will be stored by KYSat-2 over mission lifetime. To accomplish this goal, the use of deployable solar panels has been utilized to double the usable surface area of the satellite for power generation, effectively doubling the usable power of the satellite system on orbit. The KYSat-2 EPS includes of set of gold plated deployable solar panels utilizing solar cells with a 26% efficiency. Power generated by this system is fed into a shunt regulator circuit which regulates the voltage generated to be stored in a 3-cell series battery pack. Stored powered is maintained using a balancing circuit which increases the efficiency and lifetime of the cells on-orbit. Power distribution includes raw battery voltage, four high-power outputs (two 5V and two 3.3 V) and a low-noise, low power 3.3V output for use with noise sensitive devices, such as microcontrollers. The solar panel deployment system utilizes the nichrome wire which draws current

  9. determination of weibull parameters and analysis of wind power

    African Journals Online (AJOL)

    HOD

    for sustainable energy sources. The 2016 International. Energy Agency (IEA) world energy outlook report assess the growth in the renewable energy sector as quite impressive [1]. With respect to wind turbine installations, about 63,135 MW of wind power capacity was added globally in 2015 indicating a 23.2% increase.

  10. [Quantitative Analysis of Power Doppler Images in Lateral Humeral Enthesopathy].

    Science.gov (United States)

    Walder, P; Paša, L; Pavliska, L

    2016-01-01

    PURPOSE OF THE STUDY The evaluation of efficiency of power Doppler sonography in the diagnosis of lateral humeral enthesopathy, role of correct assessment of Doppler sonographic images with the method of quantitative analysis, assessment of statistical differences between a group of patients with lateral humeral enthesopathy and a control group of healthy subjects and assessment of the diagnostic power of this test. In addition, consideration of the relevance of each area of the lateral compartment for assessment and diagnosis making in lateral humeral enthesopathy. MATERIAL AND METHODS A total of 41 subjects, aged 18 to 60 years, entered the study. Thirteen patients were diagnosed with lateral humeral enthesopathy on the basis of clinical tests and a positive reaction of the lateral humeral epicondylus to administration of local anaesthetic. The control group consisted of 28 subjects without clinical signs of lateral humeral enthesopathy and subjective complaints. Power Doppler activity was evaluated in the whole region studied and in sub-regions involving the enthesis of the common extensor tendon and the periosteum of the lateral epicondyle with the area distal to it. The evaluation was based on calculating the overall surface with power Doppler activity using the method of quantitative image analysis. Each patient was measured on three occasions and the median of values obtained was used in calculation. To assess the diagnostic power of this test, all values obtained from the whole power Doppler region measured were used. The optimal dividing criterion at which the method had a maximum of sensitivity and specificity was determined. RESULTS The most evident, statistically significant difference between the patient and the control group was recorded in the whole "Range of Interest" (ROI) region (p=1.34x10-6). A significant difference was also found in sub-regions corresponding chiefly to the tendon of the extensor carpi radialis brevis muscle and to the

  11. Fractal Characteristics Analysis of Blackouts in Interconnected Power Grid

    OpenAIRE

    Wang, Feng; Li, Lijuan; Li, Canbing; Wu, Qiuwei; Cao, Yijia; Zhou, Bin; Fang, Baling

    2018-01-01

    The power failure models are a key to understand the mechanism of large scale blackouts. In this letter, the similarity of blackouts in interconnected power grids (IPGs) and their sub-grids is discovered by the fractal characteristics analysis to simplify the failure models of the IPG. The distribution characteristics of blackouts in various sub-grids are demonstrated based on the Kolmogorov-Smirnov (KS) test. The fractal dimensions (FDs) of the IPG and its sub-grids are then obtained by usin...

  12. Seismic response analysis for a deeply embedded nuclear power plant

    International Nuclear Information System (INIS)

    Chen, W.W.H.; Chatterjee, M.; Day, S.M.

    1979-01-01

    One of the important aspect of the aseimic design of nuclear power plants is the evaluation of the seismic soil-structure interaction effect due to design earthquakes. The soil-structure interaction effect can initiate rocking and result in different soil motions compared to the free field motions, thus significantly affecting the structural response. Two methods are generally used to solve the seismic soil-structure interaction problems: the direct finite element method (FLUSH) and the substructure or impedance approach. This paper presents the results of the horizontal seismic soil-structure interaction analysis using the impedance aproach and the direct finite element method for a deeply embedded nuclear power plant. (orig.)

  13. HIIT produces increases in muscle power and free testosterone in male masters athletes

    Directory of Open Access Journals (Sweden)

    P Herbert

    2017-09-01

    Full Text Available High-intensity interval training (HIIT improves peak power output (PPO in sedentary aging men but has not been examined in masters endurance athletes. Therefore, we investigated whether a six-week program of low-volume HIIT would (i improve PPO in masters athletes and (ii whether any change in PPO would be associated with steroid hormone perturbations. Seventeen male masters athletes (60 ± 5 years completed the intervention, which comprised nine HIIT sessions over six weeks. HIIT sessions involved six 30-s sprints at 40% PPO, interspersed with 3 min active recovery. Absolute PPO (799 ± 205 W and 865 ± 211 W and relative PPO (10.2 ± 2.0 W/kg and 11.0 ± 2.2 W/kg increased from pre- to post-HIIT respectively (P < 0.001, Cohen’s d = 0.32−0.38. No significant change was observed for total testosterone (15.2 ± 4.2 nmol/L to 16.4 ± 3.3 nmol/L (P = 0.061, Cohen’s d = 0.32, while a small increase in free testosterone occurred following HIIT (7.0 ± 1.2 ng/dL to 7.5 ± 1.1 ng/dL pre- to post-HIIT (P = 0.050, Cohen’s d = 0.40. Six weeks’ HIIT improves PPO in masters athletes and increases free testosterone. Taken together, these data indicate there is a place for carefully timed HIIT epochs in regimes of masters athletes.

  14. Flood risk analysis procedure for nuclear power plants

    International Nuclear Information System (INIS)

    Wagner, D.P.

    1982-01-01

    This paper describes a methodology and procedure for determining the impact of floods on nuclear power plant risk. The procedures are based on techniques of fault tree and event tree analysis and use the logic of these techniques to determine the effects of a flood on system failure probability and accident sequence occurrence frequency. The methodology can be applied independently or as an add-on analysis for an existing risk assessment. Each stage of the analysis yields useful results such as the critical flood level, failure flood level, and the flood's contribution to accident sequence occurrence frequency. The results of applications show the effects of floods on the risk from nuclear power plants analyzed in the Reactor Safety Study

  15. Multihop Capability Analysis in Wireless Information and Power Transfer Multirelay Cooperative Networks

    Directory of Open Access Journals (Sweden)

    Qilin Wu

    2018-01-01

    Full Text Available We study simultaneous wireless information and power transfer (SWIPT in multihop wireless cooperative networks, where the multihop capability that denotes the largest number of transmission hops is investigated. By utilizing the broadcast nature of multihop wireless networks, we first propose a cooperative forwarding power (CFP scheme. In CFP scheme, the multiple relays and receiver have distinctly different tasks. Specifically, multiple relays close to the transmitter harvest power from the transmitter first and then cooperatively forward the power (not the information towards the receiver. The receiver receives the information (not the power from the transmitter first, and then it harvests the power from the relays and is taken as the transmitter of the next hop. Furthermore, for performance comparison, we suggest two schemes: cooperative forwarding information and power (CFIP and direct receiving information and power (DFIP. Also, we construct an analysis model to investigate the multihop capabilities of CFP, CFIP, and DFIP schemes under the given targeted throughput requirement. Finally, simulation results validate the analysis model and show that the multihop capability of CFP is better than CFIP and DFIP, and for improving the multihop capabilities, it is best effective to increase the average number of relay nodes in cooperative set.

  16. Analysis of the efficiency of the Iberian power futures market

    International Nuclear Information System (INIS)

    Capitan Herraiz, Alvaro; Rodriguez Monroy, Carlos

    2009-01-01

    Market efficiency is analysed for the Iberian Power Futures Market and other European Power Markets, as well as other fuel markets through evaluation of ex-post Forward Risk Premium. The equilibrium price from compulsory call auctions for distribution companies within the framework of the Iberian Power Futures Market is not optimal for remuneration purposes as it seems to be slightly upward biased. In the period considered (August 2006-July 2008), monthly futures contracts behave similarly to quarterly contracts. Average risk premia have been positive in power and natural gas markets but negative in oil and coal markets. Different hypotheses are tested regarding increasing volatility with maturity and regarding Forward Risk Premium variations (decreasing with variance of spot prices during delivery period and increasing with skewness of spot prices during delivery period). Enlarged data sets are recommended for stronger test results. Energy markets tend to show limited levels of market efficiency. Regarding the emerging Iberian Power Futures Market, price efficiency is improved with market development of all the coexistent forward contracting mechanisms and with further integration of European Regional Electricity Markets. (author)

  17. Nuclear power reactor analysis, methods, algorithms and computer programs

    International Nuclear Information System (INIS)

    Matausek, M.V

    1981-01-01

    Full text: For a developing country buying its first nuclear power plants from a foreign supplier, disregarding the type and scope of the contract, there is a certain number of activities which have to be performed by local stuff and domestic organizations. This particularly applies to the choice of the nuclear fuel cycle strategy and the choice of the type and size of the reactors, to bid parameters specification, bid evaluation and final safety analysis report evaluation, as well as to in-core fuel management activities. In the Nuclear Engineering Department of the Boris Kidric Institute of Nuclear Sciences (NET IBK) the continual work is going on, related to the following topics: cross section and resonance integral calculations, spectrum calculations, generation of group constants, lattice and cell problems, criticality and global power distribution search, fuel burnup analysis, in-core fuel management procedures, cost analysis and power plant economics, safety and accident analysis, shielding problems and environmental impact studies, etc. The present paper gives the details of the methods developed and the results achieved, with the particular emphasis on the NET IBK computer program package for the needs of planning, construction and operation of nuclear power plants. The main problems encountered so far were related to small working team, lack of large and powerful computers, absence of reliable basic nuclear data and shortage of experimental and empirical results for testing theoretical models. Some of these difficulties have been overcome thanks to bilateral and multilateral cooperation with developed countries, mostly through IAEA. It is the authors opinion, however, that mutual cooperation of developing countries, having similar problems and similar goals, could lead to significant results. Some activities of this kind are suggested and discussed. (author)

  18. Multiple Sclerosis Increases Fracture Risk: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Guixian Dong

    2015-01-01

    Full Text Available Purpose. The association between multiple sclerosis (MS and fracture risk has been reported, but results of previous studies remain controversial and ambiguous. To assess the association between MS and fracture risk, a meta-analysis was performed. Method. Based on comprehensive searches of the PubMed, Embase, and Web of Science, we identified outcome data from all articles estimating the association between MS and fracture risk. The pooled risk ratios (RRs with 95% confidence intervals (CIs were calculated. Results. A significant association between MS and fracture risk was found. This result remained statistically significant when the adjusted RRs were combined. Subgroup analysis stratified by the site of fracture suggested significant associations between MS and tibia fracture risk, femur fracture risk, hip fracture risk, pelvis fracture risk, vertebrae fracture risk, and humerus fracture risk. In the subgroup analysis by gender, female MS patients had increased fracture risk. When stratified by history of drug use, use of antidepressants, hypnotics/anxiolytics, anticonvulsants, and glucocorticoids increased the risk of fracture risk in MS patients. Conclusions. This meta-analysis demonstrated that MS was significantly associated with fracture risk.

  19. Power loss analysis in altered tooth-sum spur gearing

    Directory of Open Access Journals (Sweden)

    Sachidananda H. K.

    2018-01-01

    Full Text Available The main cause of power loss or dissipation of heat in case of meshed gears is due to friction existing between gear tooth mesh and is a major concern in low rotational speed gears, whereas in case of high operating speed the power loss taking place due to compression of air-lubricant mixture (churning losses and windage losses due to aerodynamic trial of air lubricant mixture which controls the total efficiency needs to be considered. Therefore, in order to improve mechanical efficiency it is necessary for gear designer during gear tooth optimization to consider these energy losses. In this research paper the power loss analysis for a tooth-sum of 100 altered by ±4% operating between a specified center distance is considered. The results show that negative altered tooth-sum gearing performs better as compared to standard and positive altered tooth-sum gearing.

  20. Thermodynamic analysis of Thermophotovoltaic Efficiency and Power Density Tradeoffs

    Energy Technology Data Exchange (ETDEWEB)

    P.F. Baldasara; J.E. Reynolds; G.W. Charache; D.M. DePoy; C.T. Ballinger; T. Donovan; J.M. Borrego

    2000-02-22

    This report presents an assessment of the efficiency and power density limitations of thermophotovoltaic (TPV) energy conversion systems for both ideal (radiative-limited) and practical (defect-limited) systems. Thermodynamics is integrated into the unique process physics of TPV conversion, and used to define the intrinsic tradeoff between power density and efficiency. The results of the analysis reveal that the selection of diode bandgap sets a limit on achievable efficiency well below the traditional Carnot level. In addition it is shown that filter performance dominates diode performance in any practical TPV system and determines the optimum bandgap for a given radiator temperature. It is demonstrated that for a given radiator temperature, lower bandgap diodes enable both higher efficiency and power density when spectral control limitations are included. The goal of this work is to provide a better understanding of the basic system limitations that will enable successful long-term development of TPV energy conversion technology.

  1. Biomechanical analysis of the knee during the power clean.

    Science.gov (United States)

    Souza, Aaron L; Shimada, Sean D

    2002-05-01

    To our knowledge, no scientific literature has examined the 3-dimensional forces acting at the knee joint during a power clean. Ten male weightlifting subjects (25.9 years, SD 3.54) performed 1 set of the power clean at 60 and 70% of their maximal collegiate level for 5 repetitions. The subjects displayed a large compressive, moderate anterior, and a small degree of lateral and medial force at the knee during both percentage lifts. The majority of these forces occurred during the second pull phase or the catching phase of the lift. Lifters with decreased weight/system weight percentages displayed a more efficient lift that placed less stress on the knees. This analysis may provide invaluable information in the assessment of weight percentages used for Olympic weightlifters throughout the training year. the power clean.

  2. Solar Stirling power generation - Systems analysis and preliminary tests

    Science.gov (United States)

    Selcuk, M. K.; Wu, Y.-C.; Moynihan, P. I.; Day, F. D., III

    1977-01-01

    The feasibility of an electric power generation system utilizing a sun-tracking parabolic concentrator and a Stirling engine/linear alternator is being evaluated. Performance predictions and cost analysis of a proposed large distributed system are discussed. Design details and preliminary test results are presented for a 9.5 ft diameter parabolic dish at the Jet Propulsion Laboratory (Caltech) Table Mountain Test Facility. Low temperature calorimetric measurements were conducted to evaluate the concentrator performance, and a helium flow system is being used to test the solar receiver at anticipated working fluid temperatures (up to 650 or 1200 C) to evaluate the receiver thermal performance. The receiver body is designed to adapt to a free-piston Stirling engine which powers a linear alternator assembly for direct electric power generation. During the next phase of the program, experiments with an engine and receiver integrated into the concentrator assembly are planned.

  3. Software and codes for analysis of concentrating solar power technologies.

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Clifford Kuofei

    2008-12-01

    This report presents a review and evaluation of software and codes that have been used to support Sandia National Laboratories concentrating solar power (CSP) program. Additional software packages developed by other institutions and companies that can potentially improve Sandia's analysis capabilities in the CSP program are also evaluated. The software and codes are grouped according to specific CSP technologies: power tower systems, linear concentrator systems, and dish/engine systems. A description of each code is presented with regard to each specific CSP technology, along with details regarding availability, maintenance, and references. A summary of all the codes is then presented with recommendations regarding the use and retention of the codes. A description of probabilistic methods for uncertainty and sensitivity analyses of concentrating solar power technologies is also provided.

  4. Dynamic Analysis & Characterization of Conventional Hydraulic Power Supply Units

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Liedhegener, Michael; Bech, Michael Møller

    2016-01-01

    Hydraulic power units operated as constant supply pres-sure systems remain to be widely used in the industry, to supply valve controlled hydraulic drives etc., where the hydraulic power units are constituted by variable pumps with mechanical outlet pressure control, driven by induction motors...... such that limited impact on the drive dynamics is observed. Such ideal properties however, are not necessarily present in industrial hydraulic applications for various reasons, with the most common being large volumes of supply lines. Long supply lines, hence large supply line volumes, between the sup-ply system...... with internal pi-lot supply are used. This paper is concerned with the analysis and characterization of the coupled pump-induction motor dy-namics, confined to hydraulic power units constituted by an axial piston pump with mechanical outlet pressure control, driven by an induction motor operated at grid...

  5. Windfarm generation assessment for reliability analysis of power systems

    DEFF Research Database (Denmark)

    Negra, N.B.; Holmstrøm, O.; Bak-Jensen, B.

    2007-01-01

    Due to the fast development of wind generation in the past ten years, increasing interest has been paid to techniques for assessing different aspects of power systems with a large amount of installed wind generation. One of these aspects concerns power system reliability. Windfarm modelling plays...... in a reliability model and the generation of a windfarm is evaluated by means of sequential Monte Carlo simulation. Results are used to analyse how each mentioned Factor influences the assessment, and why and when they should be included in the model....

  6. Windfarm Generation Assessment for Reliability Analysis of Power Systems

    DEFF Research Database (Denmark)

    Barberis Negra, Nicola; Bak-Jensen, Birgitte; Holmstrøm, O.

    2007-01-01

    Due to the fast development of wind generation in the past ten years, increasing interest has been paid to techniques for assessing different aspects of power systems with a large amount of installed wind generation. One of these aspects concerns power system reliability. Windfarm modelling plays...... in a reliability model and the generation of a windfarm is evaluated by means of sequential Monte Carlo simulation. Results are used to analyse how each mentioned Factor influences the assessment, and why and when they should be included in the model....

  7. Windfarm Generation Assessment for ReliabilityAnalysis of Power Systems

    DEFF Research Database (Denmark)

    Negra, Nicola Barberis; Holmstrøm, Ole; Bak-Jensen, Birgitte

    2007-01-01

    Due to the fast development of wind generation in the past ten years, increasing interest has been paid to techniques for assessing different aspects of power systems with a large amount of installed wind generation. One of these aspects concerns power system reliability. Windfarm modelling plays...... in a reliability model and the generation of a windfarm is evaluated by means of sequential Monte Carlo simulation. Results are used to analyse how each mentioned Factor influences the assessment, and why and when they should be included in the model....

  8. Extending the applied software in the contemporary thermal power plants for increasing the intelligence of the automatic control system

    Science.gov (United States)

    Krokhin, G.; Pestunov, A.; Arakelyan, E.; Mukhin, V.

    2017-11-01

    During the last decades, there can be noticed an increase of interest concerning various aspects of intellectual diagnostics and management in thermal power engineering according the hybrid principle. It is conditioned by the fact that conservative static methods does not allow to reflect the actual power installation state adequately. In order to improve the diagnostics quality, we use various fuzzy systems apparatus. In this paper, we introduce the intellectual system, called SKAIS, which is intended for quick and precise diagnostics of thermal power equipment. This system was developed as the result of the research carried out by specialists from National Research University “Moscow Power Engineering Institute” and Novosibirsk State University of Economics and Management. It drastically increases the level of intelligence of the automatic power plant control system.

  9. Increasing Water System Efficiency with Ultrafiltration Pre-treatment in Power Plants

    International Nuclear Information System (INIS)

    Majamaa, Katariina; Suarez, Javier; Gasia Eduard

    2012-09-01

    Water demineralization with reverse osmosis (RO) membranes has a long and successful history in water treatment for power plants. As the industry strives for more efficient, reliable and compact water systems, pressurized hollow-fiber ultrafiltration (UF) has become an increasingly appealing pre-treatment technology. Compared to conventional, non- membrane based pretreatments, ultrafiltration offers higher efficiency in the removal of suspended solids, microorganisms and colloidal matter, which are all common causes for operational challenges experienced in the RO systems. In addition, UF is more capable of handling varying feed water qualities and removes the risk of particle carry-over often seen with conventional filtration techniques. Ultrafiltration is a suitable treatment technology for various water types from surface waters to wastewater, and the more fluctuating or challenging the feed water source is, the better the benefits of UF are seen compared to conventional pretreatments. Regardless of the feed water type, ultrafiltration sustains a constant supply of high quality feed water to downstream RO, allowing a more compact and cost efficient RO system design with improved operational reliability. A detailed focus on the design and operational aspects and experiences of two plants is provided. These examples demonstrate both economical UF operation and tangible impact of RO process improvement. Experience from these plants can be leveraged to new projects. (authors)

  10. New Solutions For Increasing Environmental Protection During Severe Accidents At Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kulyukhin, Sergei A.; Mikheev, Nikolai B.; Falkovskii, Leo N.; Reshetov, Leo A.; Zvetkova, Marianna Ya.; Yagodkin, Ivan V.; Osipov, Viktor P.; Skvortsov, Sergei S.; Berkovich, Viktor M.; Taranov, Gennadii S.; Grigor'ev, Mikhail M.; Meshkov, Vladimir M.; Noskov, Andrei A.; Mitrofanov, Mikhail I.

    2008-01-01

    This paper reports new solutions for increasing environmental protection during severe accidents at NPPs. For NPPs with two protective shells and pressure release system such as WWER-1000 we suggest a new comprehensive, passive-mode environmental protection system of decontamination of the radioactive air-steam mixture from the containment and the inter-containment area, which includes the 'wet' stage (scrubbers, etc.), the 'dry' stage (sorption module), and also an ejector, which in a passive mode is capable of solving the multi-purpose task of decontamination of the air-steam mixture. For Russian WWER-440/230 NPPs we suggest three protection levels: 1) a jet-vortex condenser; 2) the spray system; 3) a sorption module. For modern designs of new generation NPPs, which do not provide for pressure release systems, we proposed a new passive filtering system together with the passive heat-removal system, which can be used during severe accidents in case all power supply units become unavailable. (authors)

  11. Randomized block experimental designs can increase the power and reproducibility of laboratory animal experiments.

    Science.gov (United States)

    Festing, Michael F W

    2014-01-01

    Randomized block experimental designs have been widely used in agricultural and industrial research for many decades. Usually they are more powerful, have higher external validity, are less subject to bias, and produce more reproducible results than the completely randomized designs typically used in research involving laboratory animals. Reproducibility can be further increased by using time as a blocking factor. These benefits can be achieved at no extra cost. A small experiment investigating the effect of an antioxidant on the activity of a liver enzyme in four inbred mouse strains, which had two replications (blocks) separated by a period of two months, illustrates this approach. The widespread failure to use these designs more widely in research involving laboratory animals has probably led to a substantial waste of animals, money, and scientific resources and slowed down the development of new treatments for human and animal diseases. © The Author 2014. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  12. Increase in the amount of evaporator concentrate from nuclear power plants in cemented products

    International Nuclear Information System (INIS)

    Costa, Bruna S.; Tello, Clédola C.O.

    2017-01-01

    Nuclear power plants, research centers and other nuclear facilities are sources of radioactive liquid waste generation. These wastes can come from cooling of the primary reactor system, cleaning spent pool of fuel, washing contaminated clothing, among others. One of the most used methods for the treatment of these aqueous flows is the evaporation, which generates the concentrate of the evaporator, waste classified as low and medium level of radiation. Norms determine that radioactive waste must be minimized, and that to be accepted in repositories, they must be solidified. The work sought to reduce the volume of the evaporated concentrate waste and its subsequent solidification in cement. In order to carry out the tests, the evaporator concentrate (CE) simulation solution was prepared and then dried in an oven. Subsequently, cementation of the dry material was made using cement, fluidizer, NaOH and water. After a curing time of 28 days, the compressive strength tests were made for all specimens obtained, and for the samples that obtained resistance above that required by the norm, which is 10MPa, the percentages of reject incorporated and volume reduction. The results showed that, by drying the evaporator concentrate, it was possible to reduce the volume of the waste generated by up to 27% in relation to the waste without drying, which shows that drying is an effective way to increase the incorporation of the evaporator concentrate in packaged waste

  13. The Photovoltaic Heat Island Effect: Larger solar power plants increase local temperatures

    Science.gov (United States)

    Allen, N.; Minor, R. L.; Pavao-Zuckerman, M.; Barron-Gafford, G.

    2016-12-01

    While photovoltaic (PV) renewable energy production has surged, concerns remain about whether or not PV power plants induce a "heat island" (PVHI) effect, much like the increase in ambient temperatures relative to wildlands generates an Urban Heat Island effect in cities. Transitions to PV plants likely alter the way that incoming energy is reflected back to the atmosphere or absorbed, stored, and reradiated as latent or sensible heat because PV plants change the albedo, vegetation, and structure of the terrain. Prior synthetic work on the PVHI has been mostly theoretical or simulated models, and past empirical work has been limited in scope to a single biome. Thus, there are large uncertainties surrounding the potential for a PHVI effect, so we examined the PVHI in empirical and experimental terms. We found temperatures over a PV plant were regularly 3-4oC warmer than wildlands at night, which is in direct contrast to modeling studies suggesting PV systems should decrease ambient temperatures. Deducing the underlying cause and scale of the PVHI effect and identifying mitigation strategies are key in supporting decision-making regarding PV development, particularly in semiarid landscapes, which are among the most likely for large-scale PV installations.

  14. Power Estimation for Gene-Longevity Association Analysis Using Concordant Twins

    DEFF Research Database (Denmark)

    Tan, Qihua; Zhao, Jing Hua; Kruse, Torben A

    2014-01-01

    Statistical power is one of the major concerns in genetic association studies. Related individuals such as twins are valuable samples for genetic studies because of their genetic relatedness. Phenotype similarity in twin pairs provides evidence of genetic control over the phenotype variation...... in a population. The genetic association study on human longevity, a complex trait that is under control of both genetic and environmental factors, has been confronted by the small sample sizes of longevity subjects which limit statistical power. Twin pairs concordant for longevity have increased probability...... for carrying beneficial genes and thus are useful samples for gene-longevity association analysis. We conducted a computer simulation to estimate the power of association study using longevity concordant twin pairs. We observed remarkable power increases in using singletons from longevity concordant twin pairs...

  15. Living near nuclear power plants and thyroid cancer risk: A systematic review and meta-analysis.

    Science.gov (United States)

    Kim, Jaeyoung; Bang, Yejin; Lee, Won Jin

    2016-02-01

    There has been public concern regarding the safety of residing near nuclear power plants, and the extent of risk for thyroid cancer among adults living near nuclear power plants has not been fully explored. In the present study, a systematic review and meta-analysis of epidemiologic studies was conducted to investigate the association between living near nuclear power plants and the risk of thyroid cancer. A comprehensive literature search was performed on studies published up to March 2015 on the association between nuclear power plants and thyroid cancer risk. The summary standardized incidence ratio (SIR), standardized mortality ratio (SMR), and 95% confidence intervals (CIs) were calculated using a random-effect model of meta-analysis. Sensitivity analyses were performed by study quality. Thirteen studies were included in the meta-analysis, covering 36 nuclear power stations in 10 countries. Overall, summary estimates showed no significant increased thyroid cancer incidence or mortality among residents living near nuclear power plants (summary SIR=0.98; 95% CI 0.87-1.11, summary SMR=0.80; 95% CI 0.62-1.04). The pooled estimates did not reveal different patterns of risk by gender, exposure definition, or reference population. However, sensitivity analysis by exposure definition showed that living less than 20 km from nuclear power plants was associated with a significant increase in the risk of thyroid cancer in well-designed studies (summary OR=1.75; 95% CI 1.17-2.64). Our study does not support an association between living near nuclear power plants and risk of thyroid cancer but does support a need for well-designed future studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Performance Analysis of a Hybrid Power Cutting System for Roadheader

    Directory of Open Access Journals (Sweden)

    Yang Yang

    2017-01-01

    Full Text Available An electrohydraulic hybrid power cutting transmission system for roadheader under specific working condition was proposed in this paper. The overall model for the new system composed of an electric motor model, a hydraulic pump-motor model, a torsional planetary set model, and a hybrid power train model was established. The working mode characteristics were simulated under the conditions of taking the effect of cutting picks into account. The advantages of new hybrid power cutting system about the dynamic response under shock load were investigated compared with the traditional cutting system. The results illustrated that the hybrid power system had an obvious cushioning in terms of the dynamic load of cutting electric motor and planetary gear set. Besides, the hydraulic motor could provide an auxiliary power to improve the performance of the electric motor. With further analysis, a dynamic load was found to have a high relation to the stiffness and damping of coupling in the transmission train. The results could be a useful guide for the design of cutting transmission of roadheader.

  17. An analysis of electric utility embedded power supply costs

    International Nuclear Information System (INIS)

    Kahal, M.; Brown, D.

    1998-01-01

    There is little doubt that for the vast majority of electric utilities the embedded costs of power supply exceed market prices, giving rise to the stranded cost problem. Beyond that simple generalization, there are a number of crucial questions, which this study attempts to answer. What are the regional patterns of embedded cost differences? To what extent is the cost problem attributable to nuclear power? How does the cost of purchased power compare to the cost of utility self-generation? What is the breakdown of utility embedded generation costs between operating costs - which are potentially avoidable--and ownership costs, which by definition are ''sunk'' and therefore not avoidable? How will embedded generation costs and market prices compare over time? These are the crucial questions for states as they address retail-restructuring proposal. This study presents an analysis of generation costs, which addresses these key questions. A computerized costing model was developed and applied using FERC Form 1 data for 1995. The model analyzed embedded power supply costs (i.e.; self-generation plus purchased power) for two groups of investor-owned utilities, 49 non-nuclear vs. 63 nuclear. These two subsamples represent substantially the entire US investor-owned electric utility industry. For each utility, embedded cost is estimated both at busbar and at meter

  18. Carbon auctions, energy markets and market power: An experimental analysis

    International Nuclear Information System (INIS)

    Dormady, Noah C.

    2014-01-01

    This paper provides an experimental analysis of a simultaneous energy-emissions market under conditions of market power. The experimental design employs real-world institutional features; including stochastic demand, permit banking, inter-temporal (multi-round) dynamics, a tightening cap, and resale. The results suggest that dominant firms can utilize energy-emissions market linkages to simultaneously inflate the price of energy and suppress the price of emissions allowances. Whereas under prior market designs, regulators were concerned with dominant firms exercising their market power over the emissions market to exclude rivals and manipulate the permit market by hoarding permits; the results of this paper suggest that this strategy is less profitable to dominant firms in contemporary auction-based markets than strategic capacity withholding in the energy market and associated demand reduction in the emissions market. - Highlights: • Laboratory simulation of joint energy-emissions market. • Evaluates market power under collusion and real-world institutional features. • Dominant firms can exercise market power to inflate energy prices. • Dominant firms can exercise market power to suppress emissions prices. • Supply withholding is an implicit demand reduction in the emissions market

  19. Power quality analysis of STATCOM using dynamic phasor modeling

    Energy Technology Data Exchange (ETDEWEB)

    Hannan, M.A.; Mohamed, A.; Hussain, A.; AI-Dabbagh, Majid [Department of Electrical, Electronic and Systems Engineering, Faculty of Engineering, National University of Malaysia, 43600 Bangi, Selangor (Malaysia)

    2009-06-15

    Modeling of synchronous static compensator (STATCOM) of a power system based on the dynamic phasor model to investigate the performance of STATCOM for power quality analysis is described. It is compared with electromagnetic transient program (EMTP) like simulation. The dynamic phasor model and electromagnetic transient (EMT) model of the STATCOM including the power system are implemented in Matlab/Simulink toolbox and PSCAD/EMTDC, respectively. STATCOM dynamic phasor model including switching functions and their control system are presented. A satisfactory solution for power quality problems on typical distribution network is analyzed using the dynamic phasor model and EMTP like PSCAD/EMTDC simulation techniques. The simulation results revealed that the dynamic phasor model of STATCOM is in excellent agreement with the detailed time-domain EMT model of PSCAD/EMTDC simulation. The dynamic behavior of STATCOM using phasor model can be applied for analyzing power quality issues. It is found faster in speed and higher accuracy can be obtained and correlates well with PSCAD/EMTDC simulation results. (author)

  20. Power sale. An activity of increasing importance in S.N Nuclearelectrica S.A

    International Nuclear Information System (INIS)

    Metes, Mircea

    2006-01-01

    The paper discusses the main characteristics of the power market in Romania. S. N. Nuclearelectrica S.A., the operator of Cernavoda nuclear power plant, is a new power supplier on this market. The price formation of the power sold by S. N. Nuclearelectrica S. A., its participation to the power market as well as the structure of the production costs at Cernavoda NPP are presented. The paper has the following contents: The electricity companies; - From service supplier to wholesale dealer; - Regulated contracts vs. free market; - The shock from 1 July 2005; - The last but not the final challenge. At the above noted date two events with an direct impact upon the power sale by Nuclearelectrica S.A. in Romania took place: 1.The new Trade Code of the power gross market became operative; 2. The opening degree of the free market raised steeply from 55% to over 83% of the energy demand, all the industrial consumers having the right of having the statute of 'eligible consumer'. The conclusion of the paper is that the reduced production cost in the nuclear unit as compared with those of classical stations, as well as a correct planning of the production are favorable premises to a successful transaction and sale of power produced at Cernavoda NPP

  1. Economic costs of managing of an electricity grid with increasing wind power penetration

    NARCIS (Netherlands)

    Prescott, R.; Kooten, van G.C.

    2009-01-01

    We examine the impact of policy choices, including a carbon tax, on the optimal allocation of power across different generation sources and on future investments in generating facilities. The main focus is on the Alberta power grid, as it is heavily dependent on fossil fuels and has only limited

  2. A Power System Network Splitting Strategy Based on Contingency Analysis

    Directory of Open Access Journals (Sweden)

    Nur Zawani Saharuddin

    2018-02-01

    Full Text Available This paper proposes a network splitting strategy following critical line outages based on N-1 contingency analysis. Network splitting is the best option for certain critical outages when the tendency of severe cascading failures is very high. Network splitting is executed by splitting the power system network into feasible set of islands. Thus, it is essential to identify the optimal splitting solution (in terms of minimal power flow disruption that satisfies certain constraints. This paper determines the optimal splitting solution for each of the critical line outage using discrete evolutionary programming (DEP optimization technique assisted by heuristic initialization approach. Heuristic initialization provides the best initial cutsets which will guide the optimization technique to find the optimal splitting solution. Generation–load balance and transmission line overloading analysis are carried out in each island to ensure the steady state stability is achieved. Load shedding scheme is initiated if the power balance criterion is violated in any island to sustain the generation–load balance. The proposed technique is validated on the IEEE 118 bus system. Results show that the proposed approach produces an optimal splitting solution with lower power flow disruption during network splitting execution.

  3. An Empirical Algorithm for Power Analysis in Deep Submicron Electronic Designs

    Directory of Open Access Journals (Sweden)

    May Huang

    2002-01-01

    Full Text Available An empirical algorithm applied to logic level power analysis in deep submicron VLSI designs is introduced in the paper. The method explores a static analysis strategy using unit functions to represent signal transitions. It can be extended to the use of a Register Transfer Level (RTL power analysis after RTL codes are translated to Boolean equations. A new method for representing state-dependent power models is also introduced in the paper to reduce the complexity of power modeling and to improve the performance of power analysis. The modeling method supports not only the empirical power analysis, but also general simulation-based power analysis methods.

  4. Synthesis on power electronics for large fuel cells: From power conditioning to potentiodynamic analysis technique

    International Nuclear Information System (INIS)

    De Bernardinis, Alexandre

    2014-01-01

    Highlights: • Active load for fuel cell managing electrical drive constraints: frequency and current ripple can be adjusted independently. • Multi-port resonant soft-switched topology for power management of a thirty kilowatt segmented PEM fuel cell. • Splitting current control strategy for power segmented PEM fuel cell in case of a segment is under fault. • Reversible Buck topology for large fuel cell with control of the fuel cell potential linked to current density nonlinearity. - Abstract: The work addressed in this paper deals with a synthesis on power electronic converters used for fuel cells. The knowledge gap concerns conceptually different electronic converter architectures for PEM (Proton Exchange Membrane) fuel cells able to perform three types of functionalities: The first one is the capacity of emulating an active load representative of electrical drive constraints. In that case, frequency and fuel cell current ripple can be set independently to investigate the dynamic behavior of the fuel cell. The second one is power conditioning applied to large high power and segmented fuel cell systems (“Large” represents several tens of cells and multi-kilowatt stacks), which is a non trivial consideration regarding the topological choices to be made for improving efficiency, compactness and ensure operation under faulty condition. A multi-port resonant isolated boost topology is analyzed enabling soft switching over a large operating range for a thirty kilowatt segmented fuel cell. A splitting current control strategy in case of a segment is under fault is proposed. Each considered converter topologies meet specific constraints regarding fuel cell stack design and power level. The third functionality is the ability for the power electronics to perform analysis and diagnosis techniques, like the cyclic voltammetry on large PEM fuel cell assemblies. The latter technique is an uncommon process for large fuel cell stacks since it is rather performed on

  5. Analysis of the method for compensative power in the electricity supply networks based on portable electric power station

    OpenAIRE

    Karamnov, A.

    2006-01-01

    In this paper we consider a base technology for compensating the reactive power in electricity supply networks based on portable electric power stations (e.g. bank of capacitors, synchronous motors, barier-layer statistical reactive power source). Analysis of advantages and disadvantages for considered engineering solutions is performed.

  6. Human factor analysis and preventive countermeasures in nuclear power plant

    International Nuclear Information System (INIS)

    Li Ye

    2010-01-01

    Based on the human error analysis theory and the characteristics of maintenance in a nuclear power plant, human factors of maintenance in NPP are divided into three different areas: human, technology, and organization. Which is defined as individual factors, including psychological factors, physiological characteristics, health status, level of knowledge and interpersonal skills; The technical factors including technology, equipment, tools, working order, etc.; The organizational factors including management, information exchange, education, working environment, team building and leadership management,etc The analysis found that organizational factors can directly or indirectly affect the behavior of staff and technical factors, is the most basic human error factor. Based on this nuclear power plant to reduce human error and measures the response. (authors)

  7. Digital Processor Module Reliability Analysis of Nuclear Power Plant

    International Nuclear Information System (INIS)

    Lee, Sang Yong; Jung, Jae Hyun; Kim, Jae Ho; Kim, Sung Hun

    2005-01-01

    The system used in plant, military equipment, satellite, etc. consists of many electronic parts as control module, which requires relatively high reliability than other commercial electronic products. Specially, Nuclear power plant related to the radiation safety requires high safety and reliability, so most parts apply to Military-Standard level. Reliability prediction method provides the rational basis of system designs and also provides the safety significance of system operations. Thus various reliability prediction tools have been developed in recent decades, among of them, the MI-HDBK-217 method has been widely used as a powerful tool for the prediction. In this work, It is explained that reliability analysis work for Digital Processor Module (DPM, control module of SMART) is performed by Parts Stress Method based on MIL-HDBK-217F NOTICE2. We are using the Relex 7.6 of Relex software corporation, because reliability analysis process requires enormous part libraries and data for failure rate calculation

  8. Analysis of debt leveraging in private power projects

    International Nuclear Information System (INIS)

    Kahn, E.P.; Meal, M.; Doerrer, S.; Morse, S.

    1992-08-01

    As private power (non-utility generation) has grown to become a significant part of the electricity system, increasing concern about its financial implications has arisen. In many cases, the source of this concern has been the substantial reliance of these projects on debt financing. This study examines debt leveraging in private power projects. The policy debate on these issues has typically been conducted at a high level of generality. Critics of the private power industry assert that high debt leveraging confers an unfair competitive advantage by lowering the cost of capital, and that this leveraging is only possible because risks are shifted to the utility. Further, debt leveraging is claimed to be a threat to reliability. On the opposite side, it is argued that debt leveraging imposes costs and obligations not home by utilities, and so there is no financial advantage. The private producers also argue that on balance more risk is shifted away from utilities than to them, and that incentives for reliability are strong. In this study we examine the project finance mechanisms used in private power lending in detail, relying on a sample of actual loan documents. This review and its findings should be relevant to the further evolution of this debate. State regulatory commissions are likely to be interested in it, and Federal legislation to amend the Public Utility Holding Company Act (PUHCA) could require states to consider the implications of debt leveraging in relation to their oversight of utility power purchase programs

  9. An Empirical Analysis of a Dominant Firm's Market Power in a Restructured Electricity Market, A Case Study of Colorado

    National Research Council Canada - National Science Library

    Sweetser, Wilmer

    1998-01-01

    ...., there are 32 states where one firm owns at least 40% of the existing generation. As these states consider electric restructuring, analysis of the market power that a dominant firm can exercise could become increasingly important...

  10. Bifurcation Analysis of a DC-DC Bidirectional Power Converter Operating with Constant Power Loads

    Science.gov (United States)

    Cristiano, Rony; Pagano, Daniel J.; Benadero, Luis; Ponce, Enrique

    Direct current (DC) microgrids (MGs) are an emergent option to satisfy new demands for power quality and integration of renewable resources in electrical distribution systems. This work addresses the large-signal stability analysis of a DC-DC bidirectional converter (DBC) connected to a storage device in an islanding MG. This converter is responsible for controlling the balance of power (load demand and generation) under constant power loads (CPLs). In order to control the DC bus voltage through a DBC, we propose a robust sliding mode control (SMC) based on a washout filter. Dynamical systems techniques are exploited to assess the quality of this switching control strategy. In this sense, a bifurcation analysis is performed to study the nonlinear stability of a reduced model of this system. The appearance of different bifurcations when load parameters and control gains are changed is studied in detail. In the specific case of Teixeira Singularity (TS) bifurcation, some experimental results are provided, confirming the mathematical predictions. Both a deeper insight in the dynamic behavior of the controlled system and valuable design criteria are obtained.

  11. The software safety analysis based on SFTA for reactor power regulating system in nuclear power plant

    International Nuclear Information System (INIS)

    Liu Zhaohui; Yang Xiaohua; Liao Longtao; Wu Zhiqiang

    2015-01-01

    The digitalized Instrumentation and Control (I and C) system of Nuclear power plants can provide many advantages. However, digital control systems induce new failure modes that differ from those of analog control systems. While the cost effectiveness and flexibility of software is widely recognized, it is very difficult to achieve and prove high levels of dependability and safety assurance for the functions performed by process control software, due to the very flexibility and potential complexity of the software itself. Software safety analysis (SSA) was one way to improve the software safety by identify the system hazards caused by software failure. This paper describes the application of a software fault tree analysis (SFTA) at the software design phase. At first, we evaluate all the software modules of the reactor power regulating system in nuclear power plant and identify various hazards. The SFTA was applied to some critical modules selected from the previous step. At last, we get some new hazards that had not been identified in the prior processes of the document evaluation which were helpful for our design. (author)

  12. Nuclear power and the public: analysis of collected survey research

    International Nuclear Information System (INIS)

    Melber, B.D.; Nealey, S.M.; Hammersla, J.; Rankin, W.L.

    1977-11-01

    This executive summary highlights the major findings of a comprehensive synthesis and analysis of over 100 existing surveys dealing with public attitudes toward nuclear power issues. Questions of immediate policy relevance to the nuclear debate are posed and answered on the basis of these major findings. For each issue area, those sections of the report in which more-detailed discussion and presentation of relevant data may be found are indicated

  13. Power Analysis of an Automated Dynamic Cone Penetrometer

    Science.gov (United States)

    2015-09-01

    ARL-TR-7494 ● SEP 2015 US Army Research Laboratory Power Analysis of an Automated Dynamic Cone Penetrometer by C Wesley...Automated Dynamic Cone Penetrometer by C Wesley Tipton IV and Donald H Porschet Sensors and Electron Devices Directorate, ARL...Dynamic Cone Penetrometer 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) C Wesley Tipton IV and Donald H

  14. Nuclear power and the public: analysis of collected survey research

    Energy Technology Data Exchange (ETDEWEB)

    Melber, B.D.; Nealey, S.M.; Hammersla, J.; Rankin, W.L.

    1977-11-01

    This executive summary highlights the major findings of a comprehensive synthesis and analysis of over 100 existing surveys dealing with public attitudes toward nuclear power issues. Questions of immediate policy relevance to the nuclear debate are posed and answered on the basis of these major findings. For each issue area, those sections of the report in which more-detailed discussion and presentation of relevant data may be found are indicated.

  15. RSA Power Analysis Obfuscation: A Dynamic FPGA Architecture

    Science.gov (United States)

    2012-03-01

    18 2.3.5 Dual-Rail Logic ( DRL ) and Wave Dynamic Dif- ferential Logic (WDDL) . . . . . . . . . . . . 19 2.3.6 Time Delay...of the cryptographic circuitry. 2.3.5 Dual-Rail Logic ( DRL ) and Wave Dynamic Differential Logic (WDDL). DRL and WDDL are logic level countermeasures to...MIST : An Efficient, Randomized Exponentiation Algorithm for Resisting Power Analysis,” Topics in Cryptology CT -RSA 2002 , edited by B. Preneel

  16. New institutional analysis of European electric power reforms

    International Nuclear Information System (INIS)

    Perez, Yannick

    2002-01-01

    This research thesis reports a comparative analysis of reforms of the electric power sector implemented in European countries. In the first part, the authors proposes a presentation of the theoretical framework adopted for this analysis which is notably based on the New Institutional Economy approach. He also proposes an approach to the electric power industry based on the Transaction Cost Theory, and presents an overview of the various European reforms in the field of electricity, and of still unresolved problems which emerged after the creation of different power markets. The next part addresses an assessment of the attractive and desirable characters of reforms which have been implemented in the United Kingdom, in Germany and in Spain, with an attempt to identify winners and losers, and to classify these reforms. In the third part, the author defines a framework for the analysis of the feasibility of reforms which combine institutional and industrial dimensions, notably by reference to Noll and Williamson works. In the last part, the author sheds a new light on the concept of credibility. He introduces the conventional arbitrage of the Transaction Cost Theory between commitment stability and flexibility to generate uncertainty. He notably shows that the main problem in centralised institutional environments, is to guarantee the stability of commitments in front of opportunism, whereas in decentralised institutional environments, the main problem is to produce flexibility to manage uncertainty [fr

  17. The Environment-Power System Analysis Tool development program. [for spacecraft power supplies

    Science.gov (United States)

    Jongeward, Gary A.; Kuharski, Robert A.; Kennedy, Eric M.; Wilcox, Katherine G.; Stevens, N. John; Putnam, Rand M.; Roche, James C.

    1989-01-01

    The Environment Power System Analysis Tool (EPSAT) is being developed to provide engineers with the ability to assess the effects of a broad range of environmental interactions on space power systems. A unique user-interface-data-dictionary code architecture oversees a collection of existing and future environmental modeling codes (e.g., neutral density) and physical interaction models (e.g., sheath ionization). The user-interface presents the engineer with tables, graphs, and plots which, under supervision of the data dictionary, are automatically updated in response to parameter change. EPSAT thus provides the engineer with a comprehensive and responsive environmental assessment tool and the scientist with a framework into which new environmental or physical models can be easily incorporated.

  18. Vibration and noise analysis in nuclear power plants

    International Nuclear Information System (INIS)

    1974-12-01

    Results of the investigations on noise and vibration analysis are presented as a follow-up study of the work published in ''On-load Surveillance of Nuclear Power Plant Components by Noise and Vibration Analysis'' EUR 5036 e. The state of the art in on-load surveillance techniques of light water reactors is given by extending the preceding studies to investigations of boiling water reactors and by summarizing the latest results of pressurized water reactors, the basis being experimental and theoretical work performed by the different organizations involved in preparing this report. Finally, some developments with respect to measurement and identification methods are discussed

  19. Thermoeconomic analysis of a power/water cogeneration plant

    International Nuclear Information System (INIS)

    Hamed, Osman A.; Al-Washmi, Hamed A.; Al-Otaibi, Holayil A.

    2006-01-01

    Cogeneration plants for simultaneous production of water and electricity are widely used in the Arabian Gulf region. They have proven to be more thermodynamically efficient and economically feasible than single purpose power generation and water production plants. Yet, there is no standard or universally applied methodology for determining unit cost of electric power generation and desalinated water production by dual purpose plants. A comprehensive literature survey to critically assess and evaluate different methods for cost application in power/water cogeneration plants is reported in this paper. Based on this analysis, an in-depth thermoeconomic study is carried out on a selected power/water cogeneration plant that employs a regenerative Rankine cycle. The system incorporates a boiler, back pressure turbine (supplying steam to two MSF distillers), a deaerator and two feed water heaters. The turbine generation is rated at 118 MW, while MSF distiller is rated at 7.7 MIGD at a top brine temperature of 105 deg. C. An appropriate costing procedure based on the available energy accounting method which divides benefits of the cogeneration configuration equitably between electricity generation and water production is used to determine the unit costs of electricity and water. Capital charges of common equipment such as the boiler, deaerator and feed water heaters as well as boiler fuel costs are distributed between power generated and desalinated water according to available energy consumption of the major subsystems. A detailed sensitivity analysis was performed to examine the impact of the variation of fuel cost, load and availability factors in addition to capital recovery factor on electricity and water production costs

  20. Merger market power analysis: Pacific Enterprises and Enova Corporation

    International Nuclear Information System (INIS)

    Bailey, S.

    1999-01-01

    The Pacific Enterprises - Enova (PE-Enova) merger may be viewed as an example of the new breed of gas and power 'convergence' mergers. The merger involved the combination of a large gas distribution utility and a contiguous gas and electric utility located in Southern California. As with most mergers, the PE-Enova merger was proposed to federal and state regulators as an opportunity to achieve ratepayer savings. However, the merger also presented an issue of vertical market power involving the substantial electric generation capacity served by Southern California Gas Company (SoCalGas) and its potential impact on electric market prices, and the associated revenues for generation assets owned by San Diego Gas and Electric (SDGandE). In order for the merger to proceed, the approval of at least five separate State and federal regulators would be required. Although much of the attention of state regulators, proponents, and intervenors surrounded the division of synergy savings between ratepayers and shareholders, the analysis of the potential for market power abuse was extensive. Intervenors presented numerous complex arguments regarding the potential adverse effects of the merger on competition. In particular, intervenors argued that the combined company would manipulate its storage and transport operations to influence the delivered price of gas to California generators, and therefore, the price of power in the wholesale electric market. The arguments surrounding the existence and impacts of market power in this case are of interest in the understanding the nature and complexity of factors that may be considered in evaluating mergers. The proceeding also provides insight into how regulators are grappling with market power issues associated with convergence mergers, and weigh merger costs and benefits

  1. Social-philosophical analysis of legitimacy conditions of state power

    Directory of Open Access Journals (Sweden)

    O. V. Antonov

    2014-03-01

    Full Text Available Social­philosophical analysis had displayed the next conditions of state power legitimacy: 1 realistic progressiveness – definition of social unacceptable innovations; 2 absorption in national consciousness – policy, which conforms to local cultural­historical peculiarities of such predisposition; 3 moderate liberal views – balance between insufficient and excessive harshness; 4 observance of contractual discipline – social­contractual essence of relationships between direction of a country and its population; 5 pretended accountability, which shows oneself in dual nature of state power, that must look clear for retention of legitimacy, on the one hand, and has to make a secret of ones immoral practices, on the other hand; 6 democratic policy, which conquers recognition of majority by means of execution of their will; 7 scientific integration – countercollision, system making factor for state power and, through state power, for whole society; 8 openness, which provides intrasystem synthesis of  all other factors thanks to incessant renewal of state power stuff by the best cadres; 9 absolute meritocracy – stuffing of state elite by figures, who have professional characteristics, which conform to people’s txpectations; 10 observance of natural rights – is based on knowing of this permanent principle of social­state  relations and on empathy of its temporal modifications; 11 actualization of natural low idea in concrete acts of transindividual interplay; 12 dosated non­interference into privacy – preventive satisfaction of human individualism; 13 organization of power instinct sublimation – policy, which fund oneself  on knowing of the fact, that this aspiration is an all people’s way, and which consists in peacemaking management of aspiration realization.

  2. A long-term analysis of pumped hydro storage to firm wind power

    International Nuclear Information System (INIS)

    Foley, A.M.; Leahy, P.G.; Li, K.; McKeogh, E.J.; Morrison, A.P.

    2015-01-01

    Highlights: • This is a long term generation analysis of a high wind power system. • A high CO 2 and fossil fuel price is closest to Ireland’s EU ETS 2020 target. • New pumped storage to firm wind is limited unless strong market costs exist. • Reserve for wind power show that ancillary services are relevant for balancing. - Abstract: Although pumped hydro storage is seen as a strategic key asset by grid operators, financing it is complicated in new liberalised markets. It could be argued that the optimum generation portfolio is now determined by the economic viability of generators based on a short to medium term return on investment. This has meant that capital intensive projects such as pumped hydro storage are less attractive for wholesale electricity companies because the payback periods are too long. In tandem a significant amount of wind power has entered the generation mix, which has resulted in operating and planning integration issues due to wind’s inherent uncertain, varying spatial and temporal nature. These integration issues can be overcome using fast acting gas peaking plant or energy storage. Most analysis of wind power integration using storage to date has used stochastic optimisation for power system balancing or arbitrage modelling to examine techno-economic viability. In this research a deterministic dynamic programming long term generation expansion model is employed to optimise the generation mix, total system costs and total carbon dioxide emissions, and unlike other studies calculates reserve to firm wind power. The key finding of this study is that the incentive to build capital-intensive pumped hydro storage to firm wind power is limited unless exogenous market costs come very strongly into play. Furthermore it was demonstrated that reserve increases with increasing wind power showing the importance of ancillary services in future power systems

  3. Analysis of electrical tree propagation in XLPE power cable insulation

    International Nuclear Information System (INIS)

    Bao Minghui; Yin Xiaogen; He Junjia

    2011-01-01

    Electrical treeing is one of the major breakdown mechanisms for solid dielectrics subjected to high electrical stress. In this paper, the characteristics of electrical tree growth in XLPE samples have been investigated. XLPE samples are obtained from a commercial XLPE power cable, in which electrical trees have been grown from pin to plane in the frequency range of 4000-10,000 Hz, voltage range of 4-10 kV, and the distances between electrodes of 1 and 2 mm. Images of trees and their growing processes were taken by a CCD camera. The fractal dimensions of electric trees were obtained by using a simple box-counting technique. The results show that the tree growth rate and fractal dimension was bigger when the frequency or voltage was higher, or the distance between electrodes was smaller. Contrary to our expectation, it has been found that when the distance between electrodes changed from 1 to 2 mm, the required voltage of the similar electrical trees decreased only 1or 2 kV. In order to evaluate the difficulties of electrical tree propagation in different conditions, a simple energy threshold analysis method has been proposed. The threshold energy, which presents the minimum energy that a charge carrier in the well at the top of the tree should have to make the tree grow, has been computed considering the length of electrical tree, the fractal dimension, and the growth time. The computed results indicate that when one of the three parameters of voltage, frequency, and local electric field increase, the trends of energy threshold can be split into 3 regions.

  4. Analysis of loss of offsite power events reported in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Volkanovski, Andrija, E-mail: Andrija.VOLKANOVSKI@ec.europa.eu [European Commission, Joint Research Centre, Institute for Energy and Transport, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Ballesteros Avila, Antonio; Peinador Veira, Miguel [European Commission, Joint Research Centre, Institute for Energy and Transport, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Kančev, Duško [Kernkraftwerk Goesgen-Daeniken AG, CH-4658 Daeniken (Switzerland); Maqua, Michael [Gesellschaft für Anlagen-und-Reaktorsicherheit (GRS) gGmbH, Schwertnergasse 1, 50667 Köln (Germany); Stephan, Jean-Luc [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), BP 17 – 92262 Fontenay-aux-Roses Cedex (France)

    2016-10-15

    Highlights: • Loss of offsite power events were identified in four databases. • Engineering analysis of relevant events was done. • The dominant root cause for LOOP are human failures. • Improved maintenance procedures can decrease the number of LOOP events. - Abstract: This paper presents the results of analysis of the loss of offsite power events (LOOP) in four databases of operational events. The screened databases include: the Gesellschaft für Anlagen und Reaktorsicherheit mbH (GRS) and Institut de Radioprotection et de Sûreté Nucléaire (IRSN) databases, the IAEA International Reporting System for Operating Experience (IRS) and the U.S. Licensee Event Reports (LER). In total 228 relevant loss of offsite power events were identified in the IRSN database, 190 in the GRS database, 120 in U.S. LER and 52 in IRS database. Identified events were classified in predefined categories. Obtained results show that the largest percentage of LOOP events is registered during On power operational mode and lasted for two minutes or more. The plant centered events is the main contributor to LOOP events identified in IRSN, GRS and IAEA IRS database. The switchyard centered events are the main contributor in events registered in the NRC LER database. The main type of failed equipment is switchyard failures in IRSN and IAEA IRS, main or secondary lines in NRC LER and busbar failures in GRS database. The dominant root cause for the LOOP events are human failures during test, inspection and maintenance followed by human failures due to the insufficient or wrong procedures. The largest number of LOOP events resulted in reactor trip followed by EDG start. The actions that can result in reduction of the number of LOOP events and minimize consequences on plant safety are identified and presented.

  5. Increasing the resilience and security of the United States' power infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Happenny, Sean F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-08-01

    The United States' power infrastructure is aging, underfunded, and vulnerable to cyber attack. Emerging smart grid technologies may take some of the burden off of existing systems and make the grid as a whole more efficient, reliable, and secure. The Pacific Northwest National Laboratory (PNNL) is funding research into several aspects of smart grid technology and grid security, creating a software simulation tool that will allow researchers to test power infrastructure control and distribution paradigms by utilizing different smart grid technologies to determine how the grid and these technologies react under different circumstances. Understanding how these systems behave in real-world conditions will lead to new ways to make our power infrastructure more resilient and secure. Demonstrating security in embedded systems is another research area PNNL is tackling. Many of the systems controlling the U.S. critical infrastructure, such as the power grid, lack integrated security and the aging networks protecting them are becoming easier to attack.

  6. Reliability and mass analysis of lunar-based reactor/stirling cycle power plants

    International Nuclear Information System (INIS)

    Bloomfield, H.S.

    1989-01-01

    The purpose of this analysis was to determine the mass and reliability characteristics of nuclear reactor/Stirling cycle power plant configurations that could provide 800 kW of electricity for a proposed National Aeronautics and Space Administration (NASA) lunar surface base. The specific goal of the work was to define and characterize minimum mass power plant configurations that could provide an acceptable system reliability risk. A generic power plant design concept that exhibited potential construction feasibility and met human-rated radiation dose criteria was developed to serve as the basis for the power plant configurations assessed in this study. A combinatorial reliability analysis model based on parallel, redundant, series, and r-out-of-n system and component configurations was used to improve system reliability to an acceptable risk level. As a result of this study, an increased awareness of the importance of reliability analyses on high-capacity space power system design configurations has evolved, and future NASA mission application studies requiring high power levels for electric propulsion and orbital or planetary surface operations will benefit from this type of analysis

  7. Engineering works for increasing earthquake resistance of Hamaoka nuclear power plant

    International Nuclear Information System (INIS)

    Oonishi, Yoshihiro; Kondou, Makoto; Hattori, Kazushi

    2007-01-01

    The improvement works of the ground of outdoor piping and duct system of Hamaoka-3, one of engineering works for increasing earthquake resistance of the plant, are reported. The movable outdoor piping systems were moved. SJ method, one of the high-pressure jet mixing method, improved the ground between the duct and the unmoved light oil tank on the western side, and the environmental ground. The other places were improved by the concrete replacement works. The results of ground treated by SJ method showed the high quality of stiffness and continuity. Outline of engineering works, execution of concrete replacement works, the high-pressure jet mixing method, SJ method, the quality control and treatment of the generated mud by SJ method are reported. A seismic response analysis, execution facilities, construction planning, working diagram, improvement work conditions of three methods, and steps of SJ method are illustrated. (S.Y.)

  8. Intervention analysis of power plant impact on fish populations

    International Nuclear Information System (INIS)

    Madenjian, C.P.

    1984-01-01

    Intervention analysis was applied to 10 yr (years 1973-1982) of field fish abundance data at the D. C. Cook Nuclear Power Plant, southeastern Lake Michigan. Three log-transformed catch series, comprising monthly observations, were examined for each combination of two species (alewife, Alosa pseudoharenga, or yellow perch, Perca flavescens) and gear (trawl or gill net): catch at the plant discharged transect, catch at the reference transect, and the ratio of plant catch to reference catch. Time series separated by age groups were examined. Based on intervention analysis, no change in the abundance of fish populations could be attributed to plant operation. Additionally, a modification of the intervention analysis technique was applied to investigate trends in abundance at both the plant discharge and reference transects. Significant declines were detected for abundance of alewife adults at both of the transects. Results of the trend analysis support the contention that the alewives have undergone a lakewide decrease in abundance during the 1970s

  9. Weibull distribution in reliability data analysis in nuclear power plant

    International Nuclear Information System (INIS)

    Ma Yingfei; Zhang Zhijian; Zhang Min; Zheng Gangyang

    2015-01-01

    Reliability is an important issue affecting each stage of the life cycle ranging from birth to death of a product or a system. The reliability engineering includes the equipment failure data processing, quantitative assessment of system reliability and maintenance, etc. Reliability data refers to the variety of data that describe the reliability of system or component during its operation. These data may be in the form of numbers, graphics, symbols, texts and curves. Quantitative reliability assessment is the task of the reliability data analysis. It provides the information related to preventing, detect, and correct the defects of the reliability design. Reliability data analysis under proceed with the various stages of product life cycle and reliability activities. Reliability data of Systems Structures and Components (SSCs) in Nuclear Power Plants is the key factor of probabilistic safety assessment (PSA); reliability centered maintenance and life cycle management. The Weibull distribution is widely used in reliability engineering, failure analysis, industrial engineering to represent manufacturing and delivery times. It is commonly used to model time to fail, time to repair and material strength. In this paper, an improved Weibull distribution is introduced to analyze the reliability data of the SSCs in Nuclear Power Plants. An example is given in the paper to present the result of the new method. The Weibull distribution of mechanical equipment for reliability data fitting ability is very strong in nuclear power plant. It's a widely used mathematical model for reliability analysis. The current commonly used methods are two-parameter and three-parameter Weibull distribution. Through comparison and analysis, the three-parameter Weibull distribution fits the data better. It can reflect the reliability characteristics of the equipment and it is more realistic to the actual situation. (author)

  10. Development of the EEG of school-age children and adolescents. I. Analysis of band power.

    Science.gov (United States)

    Gasser, T; Verleger, R; Bächer, P; Sroka, L

    1988-02-01

    Development in quantitative EEG parameters is studied for a sample of 158 normal children and adolescents aged 6-17 years. This is of interest both for increasing basic knowledge of human neurophysiology and for obtaining age standardized norms, useful in clinical research and applications. After selecting an appropriate epoch and correcting for EOG artifacts, the EEG at 8 derivations was submitted to spectral analysis in order to extract broad-band parameters in absolute and relative power. Change in EEG band power across age was quantified by polynomial regression analysis. This opened automatically the possibility to obtain age-standardized EEG norms. Development was for most EEG parameters non-linear, with more pronounced changes for absolute than for relative power. No sex differences and no pubertal spurt could be identified in contrast to most somatic quantities. A detailed statistical analysis revealed, however, that this might be due to using cross-sectional data. All bands except for alpha 2 decreased in absolute power, whereas the fast bands increased and the slow bands decreased in relative power. Strong evidence was found for a substituting process between theta activity and fast alpha activity.

  11. Probabilistic methods in nuclear power plant component ageing analysis

    International Nuclear Information System (INIS)

    Simola, K.

    1992-03-01

    The nuclear power plant ageing research is aimed to ensure that the plant safety and reliability are maintained at a desired level through the designed, and possibly extended lifetime. In ageing studies, the reliability of components, systems and structures is evaluated taking into account the possible time- dependent decrease in reliability. The results of analyses can be used in the evaluation of the remaining lifetime of components and in the development of preventive maintenance, testing and replacement programmes. The report discusses the use of probabilistic models in the evaluations of the ageing of nuclear power plant components. The principles of nuclear power plant ageing studies are described and examples of ageing management programmes in foreign countries are given. The use of time-dependent probabilistic models to evaluate the ageing of various components and structures is described and the application of models is demonstrated with two case studies. In the case study of motor- operated closing valves the analysis are based on failure data obtained from a power plant. In the second example, the environmentally assisted crack growth is modelled with a computer code developed in United States, and the applicability of the model is evaluated on the basis of operating experience

  12. Increasing biomass resource availability through supply chain analysis

    International Nuclear Information System (INIS)

    Welfle, Andrew; Gilbert, Paul; Thornley, Patricia

    2014-01-01

    Increased inclusion of biomass in energy strategies all over the world means that greater mobilisation of biomass resources will be required to meet demand. Strategies of many EU countries assume the future use of non-EU sourced biomass. An increasing number of studies call for the UK to consider alternative options, principally to better utilise indigenous resources. This research identifies the indigenous biomass resources that demonstrate the greatest promise for the UK bioenergy sector and evaluates the extent that different supply chain drivers influence resource availability. The analysis finds that the UK's resources with greatest primary bioenergy potential are household wastes (>115 TWh by 2050), energy crops (>100 TWh by 2050) and agricultural residues (>80 TWh by 2050). The availability of biomass waste resources was found to demonstrate great promise for the bioenergy sector, although are highly susceptible to influences, most notably by the focus of adopted waste management strategies. Biomass residue resources were found to be the resource category least susceptible to influence, with relatively high near-term availability that is forecast to increase – therefore representing a potentially robust resource for the bioenergy sector. The near-term availability of UK energy crops was found to be much less significant compared to other resource categories. Energy crops represent long-term potential for the bioenergy sector, although achieving higher limits of availability will be dependent on the successful management of key influencing drivers. The research highlights that the availability of indigenous resources is largely influenced by a few key drivers, this contradicting areas of consensus of current UK bioenergy policy. - Highlights: • As global biomass demand increases, focus is placed indigenous resources. • A Biomass Resource Model is applied to analyse UK biomass supply chain dynamics. • Biomass availability is best increased

  13. Increase of Power System Survivability with the Decision Support Tool CRIPS Based on Network Planning and Simulation Program PSS®SINCAL

    Science.gov (United States)

    Schwaegerl, Christine; Seifert, Olaf; Buschmann, Robert; Dellwing, Hermann; Geretshuber, Stefan; Leick, Claus

    The increased interconnection and automation of critical infrastructures enlarges the complexity of the dependency structures and - as consequence - the danger of cascading effects, e.g. causing area-wide blackouts in power supply networks that are currently after deregulation operated closer to their limits. New tools or an intelligent combination of existing approaches are required to increase the survivability of critical infrastructures. Within the IRRIIS project the expert system CRIPS was developed based on network simulations realised with PSS®SINCAL, an established tool to support the analysis and planning of electrical power, gas, water or heat networks. CRIPS assesses the current situation in power supply networks analysing the simulation results of the physical network behaviour and recommends corresponding decisions.

  14. Error analysis of short term wind power prediction models

    International Nuclear Information System (INIS)

    De Giorgi, Maria Grazia; Ficarella, Antonio; Tarantino, Marco

    2011-01-01

    The integration of wind farms in power networks has become an important problem. This is because the electricity produced cannot be preserved because of the high cost of storage and electricity production must follow market demand. Short-long-range wind forecasting over different lengths/periods of time is becoming an important process for the management of wind farms. Time series modelling of wind speeds is based upon the valid assumption that all the causative factors are implicitly accounted for in the sequence of occurrence of the process itself. Hence time series modelling is equivalent to physical modelling. Auto Regressive Moving Average (ARMA) models, which perform a linear mapping between inputs and outputs, and Artificial Neural Networks (ANNs) and Adaptive Neuro-Fuzzy Inference Systems (ANFIS), which perform a non-linear mapping, provide a robust approach to wind power prediction. In this work, these models are developed in order to forecast power production of a wind farm with three wind turbines, using real load data and comparing different time prediction periods. This comparative analysis takes in the first time, various forecasting methods, time horizons and a deep performance analysis focused upon the normalised mean error and the statistical distribution hereof in order to evaluate error distribution within a narrower curve and therefore forecasting methods whereby it is more improbable to make errors in prediction. (author)

  15. Analysis of engineering cycles power, refrigerating and gas liquefaction plant

    CERN Document Server

    Haywood, R W

    1991-01-01

    Extensively revised, updated and expanded, the fourth edition of this popular text provides a rigorous analytical treatment of modern energy conversion plant. Notable for both its theoretical and practical treatment of conventional and nuclear power plant, and its studies of refrigerating and gas-liquefaction plant. This fourth edition now includes material on topics of increasing concern in the fields of energy 'saving' and reduction of environmental pollution. This increased coverage deals specifically with the following areas: CHP (cogeneration) plant, studies of both gas and coal burning p

  16. Economical analysis of FV power plants according installed performance

    Directory of Open Access Journals (Sweden)

    Peter Tauš

    2009-09-01

    Full Text Available According prognosis of future development of power capacities in Slovakia till 2030 there is assumed increasing of the electricalenergy volume, produced from renewable energy sources from present 260 MW approximately to 2100 MW (Petrovič, 2008, thatpresents almost 800 % increasing! In Slovakia position of photovoltaic in this sector was due to the high investment cost and on the lastplace due to the low system efficiency. Only possible way for implementation of the photovoltaic to the energetic system of the stateis 0donation. Slovakia will go this way also.

  17. Remote Borehole Strainmeter Sites: Power system optimization improves data quality and increases equipment uptime

    Science.gov (United States)

    Pyatt, C.; Van Boskirk, E.; Gallaher, W.; Hodgkinson, K. M.; Henderson, D. B.; Gottlieb, M. H.; Johnson, W.; Fox, O.; Mencin, D.; Mattioli, G.

    2012-12-01

    The Earthscope Plate Boundary Observatory (PBO) Borehole strainmeter network consists of 74 sites, spanning the west coast of North America from Anza, California to Vancouver Island, British Columbia. Several instruments are installed at each site (including Gladwin Tensor Strainmeter, 3-component geophone, barometer, and rain gauge), with associated data storage and communications equipment. Selected sites also are co-located with high-precision GPS, tiltmeter, pore pressure sensor and metpack. The peak load for a site with VSAT communications is approximately 65W. Most sites are AC powered with battery backup systems. 21 sites are located in remote areas where AC power is unavailable; of these, 18 use solar panels and batteries as the primary power source. During O&M phase of PBO, two issues have brought the borehole solar sites into focus. First, most solar sites cannot continuously operate throughout the winter months because of inclement weather and local topography that blocks the solar array, which results in data loss. Second, high frequency noise is introduced into the instrument data stream by the solar charging system. Reducing noise levels at higher frequencies would decrease the detection threshold for short term transients, such as aseismic creep events, thus allowing researchers to leverage the overlap between simultaneous seismometer and strainmeter observations. Several improvements have been made to optimize the power system as well as decrease noise. TriStar TS-MPPT-60 solar controllers have been installed, which optimize solar flux by tracking and responding to the solar array maximum power point. The battery charge algorithm is designed to provide gains of up to 15% efficiency during winter months. In addition, the new solar controllers have been engineered to limit noise, and also feature remote network interfaces and data logging capability. For those sites where topography impacts the function of the solar power system, methanol fuel cells

  18. Dynamic analysis of WWER-1000 nuclear power plants

    International Nuclear Information System (INIS)

    Asfura, A.P.; Jordanov, M.J.

    1995-01-01

    As part of the effort to assess the seismic vulnerability of nuclear power plants in Eastern Europe, a series of dynamic analyses have been carried out for several plants. These analyses were performed using modern analysis techniques, current local seismic parameters, and local soil profiles. This paper presents a compilation of some of the seismic analyses performed for the WWER-1000 reactor buildings at the nuclear power plants of Belene and Kozloduy in Bulgaria, and Temelin in the Czech Republic. The reactor buildings at these three plants are practically identical and correspond to the standard building design for this type of reactors. The series of analyses performed for these buildings encompasses various soil profiles, seismic ground motions, and different soil-structure interaction analysis techniques and modelling. The analysis of a common structure under different conditions gives the opportunity to assess the relative importance that each of the analysis elements has in the structural responses. The use of different SSI computer programs and foundation modeling was studied for Kozloduy, and the effects of different soil conditions and site-specific seismicity were studied by comparing the responses for the three plants. In-structure acceleration response spectra were selected as the structural responses for comparison purposes

  19. Probabilistic stability analysis: the way forward for stability analysis of sustainable power systems.

    Science.gov (United States)

    Milanović, Jovica V

    2017-08-13

    Future power systems will be significantly different compared with their present states. They will be characterized by an unprecedented mix of a wide range of electricity generation and transmission technologies, as well as responsive and highly flexible demand and storage devices with significant temporal and spatial uncertainty. The importance of probabilistic approaches towards power system stability analysis, as a subsection of power system studies routinely carried out by power system operators, has been highlighted in previous research. However, it may not be feasible (or even possible) to accurately model all of the uncertainties that exist within a power system. This paper describes for the first time an integral approach to probabilistic stability analysis of power systems, including small and large angular stability and frequency stability. It provides guidance for handling uncertainties in power system stability studies and some illustrative examples of the most recent results of probabilistic stability analysis of uncertain power systems.This article is part of the themed issue 'Energy management: flexibility, risk and optimization'. © 2017 The Author(s).

  20. Small modulator reactors (SMRs) - the key to increased social acceptance of nuclear power?

    Energy Technology Data Exchange (ETDEWEB)

    Sam-Aggrey, H. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

    2014-07-01

    Small Modular Reactors (SMRs) have been touted as having the potential to spearhead a nuclear renaissance. Proponents of this view cite the relative advantages of SMRs over larger nuclear plants as reason for their optimism. Some of these merits include potential economies of mass production deriving from modular factory production, enhanced safety features, the ability to locate reactors in remote areas, and reduced requirements for technical workforces to install and maintain SMRs. Despite the optimism surrounding SMRs, nuclear power is still a contentious issue for many Canadians. The growth of nuclear power remains adversely affected by concerns over issues such as: the health and safety consequences of nuclear power generation, environmental impacts, proliferation of nuclear materials, terrorism, and radioactive waste disposal. Personal values, past nuclear accidents, and lack of trust in the industry are other factors influencing attitudes toward nuclear energy. Given that public support is pivotal to the growth of the nuclear power sector, the issues surrounding the social acceptance of SMRs should be given serious consideration. Drawing on previously published data, this paper analyses the purported qualities of SMRs with a view of determining whether these characteristics have the potential of changing public attitudes toward greater acceptance of nuclear power. (author)

  1. Small modulator reactors (SMRs) - the key to increased social acceptance of nuclear power?

    International Nuclear Information System (INIS)

    Sam-Aggrey, H.

    2014-01-01

    Small Modular Reactors (SMRs) have been touted as having the potential to spearhead a nuclear renaissance. Proponents of this view cite the relative advantages of SMRs over larger nuclear plants as reason for their optimism. Some of these merits include potential economies of mass production deriving from modular factory production, enhanced safety features, the ability to locate reactors in remote areas, and reduced requirements for technical workforces to install and maintain SMRs. Despite the optimism surrounding SMRs, nuclear power is still a contentious issue for many Canadians. The growth of nuclear power remains adversely affected by concerns over issues such as: the health and safety consequences of nuclear power generation, environmental impacts, proliferation of nuclear materials, terrorism, and radioactive waste disposal. Personal values, past nuclear accidents, and lack of trust in the industry are other factors influencing attitudes toward nuclear energy. Given that public support is pivotal to the growth of the nuclear power sector, the issues surrounding the social acceptance of SMRs should be given serious consideration. Drawing on previously published data, this paper analyses the purported qualities of SMRs with a view of determining whether these characteristics have the potential of changing public attitudes toward greater acceptance of nuclear power. (author)

  2. Analysis of the Power oscillations event in Laguna Verde Nuclear Power Plant. Preliminary Report

    International Nuclear Information System (INIS)

    Gonzalez M, V.M.; Amador G, R.; Castillo, R.; Hernandez, J.L.

    1995-01-01

    The event occurred at Unit 1 of Laguna Verde Nuclear Power Plant in January 24, 1995, is analyzed using the Ramona 3 B code. During this event, Unit 1 suffered power oscillation when operating previous to the transfer at high speed recirculating pumps. This phenomenon was timely detected by reactor operator who put the reactor in shut-down doing a manual Scram. Oscillations reached a maximum extent of 10.5% of nominal power from peak to peak with a frequency of 0.5 Hz. Preliminary evaluations show that the event did not endangered the fuel integrity. The results of simulating the reactor core with Ramona 3 B code show that this code is capable to moderate reactor oscillations. Nevertheless it will be necessary to perform a more detailed simulation of the event in order to prove that the code can predict the beginning of oscillations. It will be need an additional analysis which permit the identification of factors that influence the reactor stability in order to express recommendations and in this way avoid the recurrence of this kind of events. (Author)

  3. Exergy analysis of biomass organic Rankine cycle for power generation

    Science.gov (United States)

    Nur, T. B.; Sunoto

    2018-02-01

    The study examines proposed small biomass-fed Organic Rankine Cycle (ORC) power plant through exergy analysis. The system consists of combustion burner unit to utilize biomass as fuel, and organic Rankine cycle unit to produce power from the expander. The heat from combustion burner was transfered by thermal oil heater to evaporate ORC working fluid in the evaporator part. The effects of adding recuperator into exergy destruction were investigated. Furthermore, the results of the variations of system configurations with different operating parameters, such as the evaporating pressures, ambient temperatures, and expander pressures were analyzed. It was found that the largest exergy destruction occurs during processes are at combustion part, followed by evaporator, condenser, expander, and pump. The ORC system equipped with a recuperator unit exhibited good operational characteristics under wide range conditions compared to the one without recuperator.

  4. Thermodynamic analysis of the advanced zero emission power plant

    Directory of Open Access Journals (Sweden)

    Kotowicz Janusz

    2016-03-01

    Full Text Available The paper presents the structure and parameters of advanced zero emission power plant (AZEP. This concept is based on the replacement of the combustion chamber in a gas turbine by the membrane reactor. The reactor has three basic functions: (i oxygen separation from the air through the membrane, (ii combustion of the fuel, and (iii heat transfer to heat the oxygen-depleted air. In the discussed unit hot depleted air is expanded in a turbine and further feeds a bottoming steam cycle (BSC through the main heat recovery steam generator (HRSG. Flue gas leaving the membrane reactor feeds the second HRSG. The flue gas consist mainly of CO2 and water vapor, thus, CO2 separation involves only the flue gas drying. Results of the thermodynamic analysis of described power plant are presented.

  5. Root cause analysis for fire events at nuclear power plants

    International Nuclear Information System (INIS)

    1999-09-01

    Fire hazard has been identified as a major contributor to a plant' operational safety risk. The International nuclear power community (regulators, operators, designers) has been studying and developing tools for defending against this hazed. Considerable advances have been achieved during past two decades in design and regulatory requirements for fire safety, fire protection technology and related analytical techniques. The IAEA endeavours to provide assistance to Member States in improving fire safety in nuclear power plants. A task was launched by IAEA in 1993 with the purpose to develop guidelines and good practices, to promote advanced fire safety assessment techniques, to exchange state of the art information, and to provide engineering safety advisory services and training in the implementation of internationally accepted practices. This TECDOC addresses a systematic assessment of fire events using the root cause analysis methodology, which is recognized as an important element of fire safety assessment

  6. Power consumption analysis of operating systems for wireless sensor networks.

    Science.gov (United States)

    Lajara, Rafael; Pelegrí-Sebastiá, José; Perez Solano, Juan J

    2010-01-01

    In this paper four wireless sensor network operating systems are compared in terms of power consumption. The analysis takes into account the most common operating systems--TinyOS v1.0, TinyOS v2.0, Mantis and Contiki--running on Tmote Sky and MICAz devices. With the objective of ensuring a fair evaluation, a benchmark composed of four applications has been developed, covering the most typical tasks that a Wireless Sensor Network performs. The results show the instant and average current consumption of the devices during the execution of these applications. The experimental measurements provide a good insight into the power mode in which the device components are running at every moment, and they can be used to compare the performance of different operating systems executing the same tasks.

  7. Thermodynamic analysis of the advanced zero emission power plant

    Science.gov (United States)

    Kotowicz, Janusz; Job, Marcin

    2016-03-01

    The paper presents the structure and parameters of advanced zero emission power plant (AZEP). This concept is based on the replacement of the combustion chamber in a gas turbine by the membrane reactor. The reactor has three basic functions: (i) oxygen separation from the air through the membrane, (ii) combustion of the fuel, and (iii) heat transfer to heat the oxygen-depleted air. In the discussed unit hot depleted air is expanded in a turbine and further feeds a bottoming steam cycle (BSC) through the main heat recovery steam generator (HRSG). Flue gas leaving the membrane reactor feeds the second HRSG. The flue gas consist mainly of CO2 and water vapor, thus, CO2 separation involves only the flue gas drying. Results of the thermodynamic analysis of described power plant are presented.

  8. Power Consumption Analysis of Operating Systems for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Rafael Lajara

    2010-06-01

    Full Text Available In this paper four wireless sensor network operating systems are compared in terms of power consumption. The analysis takes into account the most common operating systems—TinyOS v1.0, TinyOS v2.0, Mantis and Contiki—running on Tmote Sky and MICAz devices. With the objective of ensuring a fair evaluation, a benchmark composed of four applications has been developed, covering the most typical tasks that a Wireless Sensor Network performs. The results show the instant and average current consumption of the devices during the execution of these applications. The experimental measurements provide a good insight into the power mode in which the device components are running at every moment, and they can be used to compare the performance of different operating systems executing the same tasks.

  9. The Analysis of SBWR Critical Power Bundle Using Cobrag Code

    Directory of Open Access Journals (Sweden)

    Yohannes Sardjono

    2013-03-01

    Full Text Available The coolant mechanism of SBWR is similar with the Dodewaard Nuclear Power Plant (NPP in the Netherlands that first went critical in 1968. The similarity of both NPP is cooled by natural convection system. These coolant concept is very related with same parameters on fuel bundle design especially fuel bundle length, core pressure drop and core flow rate as well as critical power bundle. The analysis was carried out by using COBRAG computer code. COBRAG computer code is GE Company proprietary. Basically COBRAG computer code is a tool to solve compressible three-dimensional, two fluid, three field equations for two phase flow. The three fields are the vapor field, the continuous liquid field, and the liquid drop field. This code has been applied to analyses model flow and heat transfer within the reactor core. This volume describes the finitevolume equations and the numerical solution methods used to solve these equations. This analysis of same parameters has been done i.e.; inlet sub cooling 20 BTU/lbm and 40 BTU/lbm, 1000 psi pressure and R-factor is 1.038, mass flux are 0.5 Mlb/hr.ft2, 0.75 Mlb/hr.ft2, 1.00 Mlb/hr.ft2 and 1.25 Mlb/hr.ft2. Those conditions based on history operation of some type of the cell fuel bundle line at GE Nuclear Energy. According to the results, it can be concluded that SBWR critical power bundle is 10.5 % less than current BWR critical power bundle with length reduction of 12 ft to 9 ft.

  10. Sensitivity analysis of power depression and axial power factor effect on fuel pin to temperature and related properties distribution

    International Nuclear Information System (INIS)

    Suwardi, S.

    2001-01-01

    The presented paper is a preliminary step to evaluate the effect of radial and axial distribution of power generation on thermal analysis of whole fuel pin model with large L/D ratio. The model takes into account both radial and axial distribution of power generation due to power depression and core geometry, temperature and microstructure dependent on thermal conductivity. The microstructure distribution and the gap conductance for typical steady-state situation are given for the sensitivity analysis. The temperature and thermal conductivity distribution along the radial and axial directions obtained by different power distribution is used to indicate the sensitivity of power depression and power factor on thermal aspect. The evaluation is made for one step of incremental time and steady state approach is used. The analysis has been performed using a finite element-finite difference model. The result for typical reactor fuel shows that the sensitivity is too important to be omitted in thermal model

  11. Phalanx force magnitude and trajectory deviation increased during power grip with an increased coefficient of friction at the hand-object interface.

    Science.gov (United States)

    Enders, Leah R; Seo, Na Jin

    2011-05-17

    This study examined the effect of friction between the hand and grip surface on a person's grip strategy and force generation capacity. Twelve young healthy adults performed power grip exertions on an instrumented vertical cylinder with the maximum and 50% of maximum efforts (far above the grip force required to hold the cylinder), while normal and shear forces at each phalanx of all five fingers in the direction orthogonal to the gravity were recorded. The cylinder surface was varied for high-friction rubber and low-friction paper coverings. An increase in surface friction by replacing the paper covering with the rubber covering resulted in 4% greater mean phalanx normal force (perpendicular to the cylinder surface) and 22% greater mean phalanx shear force in either the proximal or distal direction of the digits (pfriction with the rubber surface compared to the paper surface was associated with a 20% increase in the angular deviation of the phalanx force from the direction normal to the cylinder surface (p<0.05). This study demonstrates that people significantly changed the magnitude and direction of phalanx forces depending on the surface they gripped. Such change in the grip strategy appears to help increase grip force generation capacity. This finding suggests that a seemingly simple power grip exertion involves sensory feedback-based motor control, and that people's power grip capacity may be reduced in cases of numbness, glove use, or injuries resulting in reduced sensation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Vibration analysis in nuclear power plant using neural networks

    International Nuclear Information System (INIS)

    Loskiewicz-Buczak, A.; Alguindigue, I.E.

    1993-01-01

    Vibration monitoring of components in nuclear power plants has been used for a number of years. This technique involves the analysis of vibration data coming from vital components of the plant to detect features which reflect the operational state of machinery. The analysis leads to the identification of potential failures and their causes, and makes it possible to perform efficient preventive maintenance. This paper documents the authors' work on the design of a vibration monitoring methodology enhanced by neural network technology. This technology provides an attractive complement to traditional vibration analysis because of the potential of neural networks to handle data which may be distorted or noisy. This paper describes three neural networks-based methods for the automation of some of the activities related to motion and vibration monitoring in engineering systems

  13. Analysis in environmental radioactivity around Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong Woo; Han, Man Jung; Cho, Seong Won; Cho, Hong Jun; Oh, Hyeon Kyun; Lee, Jeong Min; Chang, Jae Sook [KORTIC, Taejon (Korea, Republic of)

    2003-12-15

    Twelve kinds of environmental samples such as soil, seawater, underground water, etc. around Nuclear Power Plants(NPPs) were collected. Tritium chemical analysis was tried for the samples of rain water, pine-needle, air, seawater, underground water, chinese cabbage, again of rice and milk sampled around NPPs, and surface seawater and rain water sampled over the country. Strontium in the soil that were sampled at 60 point of district in Korea were analyzed. Tritium were analyzed in 21 samples of surface seawater around the Korea peninsular that were supplied form KFRDI(National Fisheries Research and Development Institute). Sampling and chemical analysis environmental samples around Kori, Woolsung, Youngkwang, Wooljin NPPs and Taeduk science town for tritium and strontium analysis was managed according to plans. Succeed to KINS after all samples were tried.

  14. Methodology for flood risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Wagner, D.P.; Casada, M.L.; Fussell, J.B.

    1984-01-01

    The methodology for flood risk analysis described here addresses the effects of a flood on nuclear power plant safety systems. Combining the results of this method with the probability of a flood allows the effects of flooding to be included in a probabilistic risk assessment. The five-step methodology includes accident sequence screening to focus the detailed analysis efforts on the accident sequences that are significantly affected by a flood event. The quantitative results include the flood's contribution to system failure probability, accident sequence occurrence frequency and consequence category occurrence frequency. The analysis can be added to existing risk assessments without a significant loss in efficiency. The results of two example applications show the usefulness of the methodology. Both examples rely on the Reactor Safety Study for the required risk assessment inputs and present changes in the Reactor Safety Study results as a function of flood probability

  15. Principal Component Analysis - A Powerful Tool in Computing Marketing Information

    Directory of Open Access Journals (Sweden)

    Constantin C.

    2014-12-01

    Full Text Available This paper is about an instrumental research regarding a powerful multivariate data analysis method which can be used by the researchers in order to obtain valuable information for decision makers that need to solve the marketing problem a company face with. The literature stresses the need to avoid the multicollinearity phenomenon in multivariate analysis and the features of Principal Component Analysis (PCA in reducing the number of variables that could be correlated with each other to a small number of principal components that are uncorrelated. In this respect, the paper presents step-by-step the process of applying the PCA in marketing research when we use a large number of variables that naturally are collinear.

  16. The case of nuclear power: an economical analysis

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, Gustavo; Ramirez, Jose R.; Palacios, Javier C. [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca s/n, Ocoyoacac, Edo. de Mex. 52750 (Mexico)

    2009-06-15

    In this paper an analysis will be performed to assess the economical competitiveness of Nuclear Power against other base load technologies. There are several plans to build more nuclear power plants in western countries; these plans are result among other things of the fossil fuel high prices and the concern for the global warming. France started the construction of one EPR at Flamanville in 2007 and at the end of 2008 there were 17 applications before NRC for construction and operation licenses (COL) to build as much as 26 new reactor units in USA, among the designs selected are the US-EPR, APWR, ESBWR, ABWR and AP1000. Currently, there is a lot of uncertainty about what is the overnight cost for a new generation III nuclear power plant and the vendors are not providing too much information. However, it is expected that under the new economy conditions the overnight cost will be between 2500 and 3500 USD/kW, the output electricity power of the units mentioned above are between 1100 and 1600 MW, construction time, from first concrete to commercial operation, is about five years as it has been demonstrated in the latest reactors built in Asia (e.g. Japan and China), also Flamanville is under schedule and budget. In the current paper we perform a levelized electricity cost analysis using the conditions given above, to compare the generation cost of electricity using nuclear reactors against using natural gas in combined cycle plants and also coal plants. The levelized cost analysis developed here assumes overnight cost in the range of 2500 to 3500 USD/kW to assess the levelized cost impact. Also a sensitivity analysis for construction time delays and different capacity factors in the range of 80% to 90% is offered along with a uranium fuel cost sensitivity analysis. The investment scenarios considered here comprise three different discount rates, 5%, 8% and 10%. Results obtained are presented in several graphs that show under which circumstance nuclear energy is a

  17. Fault diagnosis of power transformer based on fault-tree analysis (FTA)

    Science.gov (United States)

    Wang, Yongliang; Li, Xiaoqiang; Ma, Jianwei; Li, SuoYu

    2017-05-01

    Power transformers is an important equipment in power plants and substations, power distribution transmission link is made an important hub of power systems. Its performance directly affects the quality and health of the power system reliability and stability. This paper summarizes the five parts according to the fault type power transformers, then from the time dimension divided into three stages of power transformer fault, use DGA routine analysis and infrared diagnostics criterion set power transformer running state, finally, according to the needs of power transformer fault diagnosis, by the general to the section by stepwise refinement of dendritic tree constructed power transformer fault

  18. System Evaluation and Economic Analysis of a HTGR Powered High-Temperature Electrolysis Hydrogen Production Plant

    International Nuclear Information System (INIS)

    McKellar, Michael G.; Harvego, Edwin A.; Gandrik, Anastasia A.

    2010-01-01

    A design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production has been developed. The HTE plant is powered by a high-temperature gas-cooled reactor (HTGR) whose configuration and operating conditions are based on the latest design parameters planned for the Next Generation Nuclear Plant (NGNP). The current HTGR reference design specifies a reactor power of 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 322 C and 750 C, respectively. The power conversion unit will be a Rankine steam cycle with a power conversion efficiency of 40%. The reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes a steam-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The overall system thermal-to-hydrogen production efficiency (based on the higher heating value of the produced hydrogen) is 40.4% at a hydrogen production rate of 1.75 kg/s and an oxygen production rate of 13.8 kg/s. An economic analysis of this plant was performed with realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a cost of $3.67/kg of hydrogen assuming an internal rate of return, IRR, of 12% and a debt to equity ratio of 80%/20%. A second analysis shows that if the power cycle efficiency increases to 44.4%, the hydrogen production efficiency increases to 42.8% and the hydrogen and oxygen production rates are 1.85 kg/s and 14.6 kg/s respectively. At the higher power cycle efficiency and an IRR of 12% the cost of hydrogen production is $3.50/kg.

  19. Analysis of competition and market power in the wholesale electricity market in India

    International Nuclear Information System (INIS)

    Shukla, Umesh Kumar; Thampy, Ashok

    2011-01-01

    The electricity reforms were initiated in India with the objective of promoting competition in the electricity market. In order to promote competition, the Electricity Act 2003 was enacted and various policy initiatives were taken by the Government of India. Central Electricity Regulatory Commission (CERC) also facilitated competition through the regulatory framework of availability based tariff, Indian Electricity Grid Code, open access in inter-state transmission, inter-state trading and power exchanges. Despite these initiatives, electricity prices increased in the Wholesale Electricity Market in India (WEMI). This paper analyses the market structure and competitiveness in the WEMI. There are, of course, various potential reasons for the rise in the electricity price. This paper seeks to investigate, if market power was one of the reasons for increase in market prices. Concentration ratio, Herfindahl-Hirschman index, Supply Margin Assessment, and Residual Supply Index have been used to measure market power. This paper also uses the price-cost mark-up to examine, if exercise of market power led to higher margins. The analysis suggests that market power of firms may be part of the reason for the increase in electricity prices in WEMI. The study suggests various measures to increase competition in the WEMI.

  20. Controlling for peak power extraction from microbial fuel cells can increase stack voltage and avoid cell reversal

    Science.gov (United States)

    Boghani, Hitesh C.; Papaharalabos, George; Michie, Iain; Fradler, Katrin R.; Dinsdale, Richard M.; Guwy, Alan J.; Ieropoulos, Ioannis; Greenman, John; Premier, Giuliano C.

    2014-12-01

    Microbial fuel cells (MFCs) are bioelectrochemical systems which can degrade organic materials and are increasingly seen as potential contributors to low carbon technologies, particularly in energy recovery from and treatment of wastewaters. The theoretical maximum open circuit voltage from MFCs lies in the region of 1.1 V, but is reduced substantially by overvoltage losses. Practical use of the power requires stacking or other means to increase voltage. Series stacking of MFCs with typically encountered variability in operating conditions and performance raises the risk of cell reversal, which diminishes overall power performance. A novel strategy of MFC subsystem series connectivity along with maximum power point tracking (MPPT) generates increased power from individual MFCs whilst eliminating cell reversal. MFCs fed with lower concentrations of substrate experienced voltage reversal when connected in normal series connection with one common load, but when MFCs and loads together were connected in series, the underperforming cell is effectively bypassed and maximum power is made available. It is concluded that stack voltage may be increased and cell reversal avoided using the hybrid connectivity along with MPPT. This approach may be suitable for stacked MFC operations in the event that large scale arrays/modules are deployed in treating real wastewaters.

  1. Bottoming organic Rankine cycle configurations to increase Internal Combustion Engines power output from cooling water waste heat recovery

    International Nuclear Information System (INIS)

    Peris, Bernardo; Navarro-Esbrí, Joaquín; Molés, Francisco

    2013-01-01

    This work is focused on waste heat recovery of jacket cooling water from Internal Combustion Engines (ICEs). Cooling water heat does not always find use due to its low temperature, typically around 90 °C, and usually is rejected to the ambient despite its high thermal power. An efficient way to take benefit from the ICE cooling water waste heat can be to increase the power output through suitable bottoming Organic Rankine Cycles (ORCs). Thereby, this work simulates six configurations using ten non flammable working fluids and evaluates their performances in efficiency, safety, cost and environmental terms. Results show that the Double Regenerative ORC using SES36 gets the maximum net efficiency of 7.15%, incrementing the ICE electrical efficiency up to 5.3%, although requires duplicating the number of main components and high turbine size. A more rigorous analysis, based on the system feasibility, shows that small improvements in the basic cycle provide similar gains compared to the most complex schemes proposed. So, the single Regenerative ORC using R236fa and the Reheat Regenerative ORC using R134a seem suitable cycles which provide a net efficiency of 6.55%, incrementing the ICE electrical efficiency up to 4.9%. -- Highlights: • Suitable bottoming cycles for ICE cooling water waste heat recovery are studied. • Non flammable working fluids and various ORC configurations are evaluated. • Double regenerative cycle using SES36 is the most efficient configuration. • Regenerative and reheat regenerative ORCs seem feasible cycles. • Electrical efficiency of the ICE can be improved up to 5.3%

  2. Small-Signal Modeling and Analysis of Grid-Connected Inverter with Power Differential Droop Control

    Directory of Open Access Journals (Sweden)

    Xin Chen

    2016-01-01

    Full Text Available The conventional voltage and frequency droop control strategy in grid-connected inverter suffers a major setback in the presence of disturbance by producing oscillations. Adding a power differential term in droop controller is an effective way to address such drawback. In this paper, grid-connected inverter’s small-signal models of the conventional droop control and the power differential droop control are established. The eigenvalues of the models are then determined by system matrix. The eigenvalues analysis is presented which helps in identifying the relationship between the system stability and controller parameters. It is concluded that the damping ratio of dominant low-frequency eigenvalues increased and the oscillation caused by the disturbance is suppressed when a power differential term is added to the droop control method. The MATLAB/Simulink models of grid-connected inverter with both control strategies are also established to validate the results of small-signal analysis.

  3. Increasing physical activity with mobile devices: a meta-analysis.

    Science.gov (United States)

    Fanning, Jason; Mullen, Sean P; McAuley, Edward

    2012-11-21

    Regular physical activity has established physical and mental health benefits; however, merely one quarter of the U.S. adult population meets national physical activity recommendations. In an effort to engage individuals who do not meet these guidelines, researchers have utilized popular emerging technologies, including mobile devices (ie, personal digital assistants [PDAs], mobile phones). This study is the first to synthesize current research focused on the use of mobile devices for increasing physical activity. To conduct a meta-analysis of research utilizing mobile devices to influence physical activity behavior. The aims of this review were to: (1) examine the efficacy of mobile devices in the physical activity setting, (2) explore and discuss implementation of device features across studies, and (3) make recommendations for future intervention development. We searched electronic databases (PubMed, PsychINFO, SCOPUS) and identified publications through reference lists and requests to experts in the field of mobile health. Studies were included that provided original data and aimed to influence physical activity through dissemination or collection of intervention materials with a mobile device. Data were extracted to calculate effect sizes for individual studies, as were study descriptives. A random effects meta-analysis was conducted using the Comprehensive Meta-Analysis software suite. Study quality was assessed using the quality of execution portion of the Guide to Community Preventative Services data extraction form. Four studies were of "good" quality and seven of "fair" quality. In total, 1351 individuals participated in 11 unique studies from which 18 effects were extracted and synthesized, yielding an overall weight mean effect size of g = 0.54 (95% CI = 0.17 to 0.91, P = .01). Research utilizing mobile devices is gaining in popularity, and this study suggests that this platform is an effective means for influencing physical activity behavior. Our focus

  4. Exergy Analysis of Operating Lignite Fired Thermal Power Plant

    Directory of Open Access Journals (Sweden)

    K. Murugesan

    2009-01-01

    Full Text Available The energy assessment must be made through the energy quantity as well as the quality. But the usual energy analysisevaluates the energy generally on its quantity only. However, the exergy analysis assesses the energy on quantity as well asthe quality. The aim of the exergy analysis is to identify the magnitudes and the locations of real energy losses, in order toimprove the existing systems, processes or components. The present paper deals with an exergy analysis performed on anoperating 50MWe unit of lignite fired steam power plant at Thermal Power Station-I, Neyveli Lignite Corporation Limited,Neyveli, Tamil Nadu, India. The exergy losses occurred in the various subsystems of the plant and their components havebeen calculated using the mass, energy and exergy balance equations. The distribution of the exergy losses in several plantcomponents during the real time plant running conditions has been assessed to locate the process irreversibility. The Firstlaw efficiency (energy efficiency and the Second law efficiency (exergy efficiency of the plant have also been calculated.The comparison between the energy losses and the exergy losses of the individual components of the plant shows that themaximum energy losses of 39% occur in the condenser, whereas the maximum exergy losses of 42.73% occur in the combustor.The real losses of energy which has a scope for the improvement are given as maximum exergy losses that occurredin the combustor.

  5. Sandia-Power Surety Task Force Hawaii foam analysis.

    Energy Technology Data Exchange (ETDEWEB)

    McIntyre, Annie

    2010-11-01

    The Office of Secretary of Defense (OSD) Power Surety Task Force was officially created in early 2008, after nearly two years of work in demand reduction and renewable energy technologies to support the Warfighter in Theater. The OSD Power Surety Task Force is tasked with identifying efficient energy solutions that support mission requirements. Spray foam insulation demonstrations were recently expanded beyond field structures to include military housing at Ft. Belvoir. Initial results to using the foam in both applications are favorable. This project will address the remaining key questions: (1) Can this technology help to reduce utility costs for the Installation Commander? (2) Is the foam cost effective? (3) What application differences in housing affect those key metrics? The critical need for energy solutions in Hawaii and the existing relationships among Sandia, the Department of Defense (DOD), the Department of Energy (DOE), and Forest City, make this location a logical choice for a foam demonstration. This project includes application and analysis of foam to a residential duplex at the Waikulu military community on Oahu, Hawaii, as well as reference to spray foam applied to a PACOM facility and additional foamed units on Maui, conducted during this project phase. This report concludes the analysis and describes the utilization of foam insulation at military housing in Hawaii and the subsequent data gathering and analysis.

  6. Exergetic analysis of parabolic trough solar thermal power plants

    Science.gov (United States)

    Petrakopoulou, F.; Ruperez, B.; San Miguel, G.

    2014-12-01

    A very important component to achieve sustainable development in the energy sector is the improvement of energy efficiency of widely applied thermodynamic processes. Evaluation and optimization methods of energy processes play a crucial role in fulfilling this goal. A suitable method for the evaluation and optimization of energy conversion systems has been proven to be the exergetic analysis. In this work, two parabolic trough solar thermal power plants are simulated in detail using commercial software, and they are further analysed and compared using an exergetic analysis. The first plant uses a thermal fluid to produce the steam required in a steam generator, while the second one produces the steam directly in the solar field. The analysis involves the evaluation of the individual components of the power plants, as well as the performance evaluation of the overall structures. The main goal is to detect thermodynamic inefficiencies of the two different configurations and propose measures to minimize those. We find that the two examined plants have similar main sources of exergy destruction: the solar field (parabolic trough solar collectors), followed by the steam generator. This reveals the importance of an optimal design of these particular components, which could reduce inefficiencies present in the system. The differences in the exergy destruction and exergetic efficiencies of individual components of the two plants are analyzed in detail based on comparable operational conditions.

  7. Job analysis of nuclear power reactor health physics technicians

    International Nuclear Information System (INIS)

    Davis, L.T.; Mazour, T.J.; Clark, P.V.; Todd, R.C.; Marotta, F.J.

    1984-06-01

    This report describes a project, an industry-wide Job Analysis of Nuclear Power Reactor Health Physics Technicians (HPTs), conducted by Brookhaven National Laboratory and Analysis and Technology, Inc. to provide the industry with job-performance data that can be used in systematically defining training programs in terms of required job functions responsibilities, and performance standards. The job-analysis methodology is consistent with that used by the Institute of Nuclear Power Operations (INPO) in similar industry-wide projects and includes administration of over 850 job task questionnaires to utility and contractor Health Physics Technicians throughout the country. Data collected includes task performance (difficulty, importance, and frequency) and industry-wide demographics (job levels, experience, education, and training). The results of this project discussed herein include model job descriptions for HPT positions, summaries of HPT experience, education, and training, industry-wide task listings with task-performance characteristics, and recommendations of selected tasks as a basis for HPT training development. Finally, potential future applications of the data base by utility and contractor organizations in training program development and evaluation and personnel qualifications are discussed

  8. Yoga Poses Increase Subjective Energy and State Self-Esteem in Comparison to ‘Power Poses’

    Science.gov (United States)

    Golec de Zavala, Agnieszka; Lantos, Dorottya; Bowden, Deborah

    2017-01-01

    Research on beneficial consequences of yoga focuses on the effects of yogic breathing and meditation. Less is known about the psychological effects of performing yoga postures. The present study investigated the effects of yoga poses on subjective sense of energy and self-esteem. The effects of yoga postures were compared to the effects of ‘power poses,’ which arguably increase the sense of power and self-confidence due to their association with interpersonal dominance (Carney et al., 2010). The study tested the novel prediction that yoga poses, which are not associated with interpersonal dominance but increase bodily energy, would increase the subjective feeling of energy and therefore increase self-esteem compared to ‘high power’ and ‘low power’ poses. A two factorial, between participants design was employed. Participants performed either two standing yoga poses with open front of the body (n = 19), two standing yoga poses with covered front of the body (n = 22), two expansive, high power poses (n = 21), or two constrictive, low power poses (n = 20) for 1-min each. The results showed that yoga poses in comparison to ‘power poses’ increased self-esteem. This effect was mediated by an increased subjective sense of energy and was observed when baseline trait self-esteem was controlled for. These results suggest that the effects of performing open, expansive body postures may be driven by processes other than the poses’ association with interpersonal power and dominance. This study demonstrates that positive effects of yoga practice can occur after performing yoga poses for only 2 min. PMID:28553249

  9. Yoga Poses Increase Subjective Energy and State Self-Esteem in Comparison to ‘Power Poses’

    Directory of Open Access Journals (Sweden)

    Agnieszka Golec de Zavala

    2017-05-01

    Full Text Available Research on beneficial consequences of yoga focuses on the effects of yogic breathing and meditation. Less is known about the psychological effects of performing yoga postures. The present study investigated the effects of yoga poses on subjective sense of energy and self-esteem. The effects of yoga postures were compared to the effects of ‘power poses,’ which arguably increase the sense of power and self-confidence due to their association with interpersonal dominance (Carney et al., 2010. The study tested the novel prediction that yoga poses, which are not associated with interpersonal dominance but increase bodily energy, would increase the subjective feeling of energy and therefore increase self-esteem compared to ‘high power’ and ‘low power’ poses. A two factorial, between participants design was employed. Participants performed either two standing yoga poses with open front of the body (n = 19, two standing yoga poses with covered front of the body (n = 22, two expansive, high power poses (n = 21, or two constrictive, low power poses (n = 20 for 1-min each. The results showed that yoga poses in comparison to ‘power poses’ increased self-esteem. This effect was mediated by an increased subjective sense of energy and was observed when baseline trait self-esteem was controlled for. These results suggest that the effects of performing open, expansive body postures may be driven by processes other than the poses’ association with interpersonal power and dominance. This study demonstrates that positive effects of yoga practice can occur after performing yoga poses for only 2 min.

  10. Second law analysis of a conventional steam power plant

    Science.gov (United States)

    Liu, Geng; Turner, Robert H.; Cengel, Yunus A.

    1993-01-01

    A numerical investigation of exergy destroyed by operation of a conventional steam power plant is computed via an exergy cascade. An order of magnitude analysis shows that exergy destruction is dominated by combustion and heat transfer across temperature differences inside the boiler, and conversion of energy entering the turbine/generator sets from thermal to electrical. Combustion and heat transfer inside the boiler accounts for 53.83 percent of the total exergy destruction. Converting thermal energy into electrical energy is responsible for 41.34 percent of the total exergy destruction. Heat transfer across the condenser accounts for 2.89 percent of the total exergy destruction. Fluid flow with friction is responsible for 0.50 percent of the total exergy destruction. The boiler feed pump turbine accounts for 0.25 percent of the total exergy destruction. Fluid flow mixing is responsible for 0.23 percent of the total exergy destruction. Other equipment including gland steam condenser, drain cooler, deaerator and heat exchangers are, in the aggregate, responsible for less than one percent of the total exergy destruction. An energy analysis is also given for comparison of exergy cascade to energy cascade. Efficiencies based on both the first law and second law of thermodynamics are calculated for a number of components and for the plant. The results show that high first law efficiency does not mean high second law efficiency. Therefore, the second law analysis has been proven to be a more powerful tool in pinpointing real losses. The procedure used to determine total exergy destruction and second law efficiency can be used in a conceptual design and parametric study to evaluate the performance of other steam power plants and other thermal systems.

  11. The IAEA, nuclear power and sustainable development. Maintaining and increasing the overall assets available to future generations

    International Nuclear Information System (INIS)

    2001-01-01

    In the framework of one of the fundamental objectives of the IAEA mandate to enhance the contribution of nuclear technologies towards meeting the needs of Member States, the present status, all the aspects, and the future of nuclear power are reviewed. The development of nuclear power broadens the natural resource base usable for energy production, increases human and man-made capital, and when safely handled has little impact on ecosystems. This means that it could meet the central goal of sustainable development, considering that it covers maintaining or increasing the overall assets available to future generations, while minimizing consumption of finite resources and not exceeding the carrying capacities of ecosystems

  12. Development of RCM analysis software for Korean nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Ho; Choi, Kwang Hee; Jeong, Hyeong Jong [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    1998-12-31

    A software called KEPCO RCM workstation (KRCM) has been developed to optimize the maintenance strategies of Korean nuclear power plants. The program modules of the KRCM were designed in a manner that combines EPRI methodologies and KEPRI analysis technique. The KRCM is being applied to the three pilot system, chemical and volume control system, main steam system, and compressed air system of Yonggwang Units 1 and 2. In addition, the KRCM can be utilized as a tool to meet a part of the requirements of maintenance rule (MR) imposed by U.S. NRC. 3 refs., 4 figs. (Author)

  13. SPS market analysis. [small solar thermal power systems

    Science.gov (United States)

    Goff, H. C.

    1980-01-01

    A market analysis task included personal interviews by GE personnel and supplemental mail surveys to acquire statistical data and to identify and measure attitudes, reactions and intentions of prospective small solar thermal power systems (SPS) users. Over 500 firms were contacted, including three ownership classes of electric utilities, industrial firms in the top SIC codes for energy consumption, and design engineering firms. A market demand model was developed which utilizes the data base developed by personal interviews and surveys, and projected energy price and consumption data to perform sensitivity analyses and estimate potential markets for SPS.

  14. Elastohydrodynamic analysis using a power law pressure-viscosity relation

    Science.gov (United States)

    Loewenthal, S. H.; Zaretsky, E. V.

    1973-01-01

    An isothermal elastohydrodynamic (EHD) inlet analysis of the Grubin type which considers a power law pressure-viscosity relation and a finite pressure at the inlet edge of the Hertzian contact zone was performed. Comparisons made with published X-ray EHD film thickness data for a synthetic paraffinic oil and when conventional EHD theory showed that the present theory exhibits a slightly stronger film thickness load dependence than do previous isothermal EHD theories but far less than that exhibited by the measured data.

  15. Analysis of operating experience of nuclear power plants

    International Nuclear Information System (INIS)

    Volta, G.; Amesz, J.; Mancini, G.

    1981-01-01

    The power reactors operating experience has been matter for studies at the Joint Research Centre of the C.E.C. with the aim of validating probabilistic analysis models and of setting up data banks concerning reliability, availability of components and systems and safety related events. The report shows problems encountered and solutions given to attain the goal. For what concerns validation, the need of more satisfactory models that could handle both the technical and the organizational aspects of an operating plant is shown. For what concerns the data banks the possibilities opened by a coherent international system of classification are underlined. (author)

  16. Cost-benefit analysis for combined heat and power plant

    International Nuclear Information System (INIS)

    Sazdovski, Ace; Fushtikj, Vangel

    2004-01-01

    The paper presents a methodology and practical application of Cost-Benefit Analysis for Combined Heat and Power Plant (Cogeneration facility). Methodology include up-to-date and real data for cogeneration plant in accordance with the trends ill development of the CHP technology. As a case study a CHP plant that could be built-up in Republic of Macedonia is analyzed. The main economic parameters for project evaluation, such as NPV and IRR are calculated for a number of possible scenarios. The analyze present the economic outputs that could be used as a decision for CHP project acceptance for investment. (Author)

  17. Sensitivity Analysis of Power Distribution Synthesis Method for Failed In core Detector

    International Nuclear Information System (INIS)

    Koo, Bonseung; Cho, Jinyoung; Kim, Kyoyoun

    2013-01-01

    In this paper, performance of RCOMS 3-D power distribution synthesis method is evaluated and sensitivity analysis for the number of failed detector is tested. The performance of a 3-dimensional power distribution synthesis method (DPCM3D) was evaluated for the digital core monitoring system (RCOMS). RCOMS shows negligible power distribution errors and less sensitive to the number of available detectors compared with COLSS. By employing a DPCM3D method in RCOMS, it is judged that a core power distribution could be synthesized more accurately by eliminating the fitting error with a minimum available detector numbers and it would lead to thermal margin increase. A 3-dimensional power distribution synthesis method (called DPCM3D) has been developed by KAERI. RCOMS(Real-time calculator for COre Monitoring System) adopts the method instead of Fourier expansion method being used in COLSS of conventional PWRs. COLSS generates level-averaged detector responses from in core detector signals and fits core average axial power shape. Thus, COLSS inevitably includes considerable fitting error in itself. However, DPCM3D produces a synthetic 3-D power distribution by coupling a neutronics code and measured in core detector signals without any fitting

  18. Methods for seismic analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Gantenbein, F.

    1990-01-01

    The seismic analysis of a complex structure, such as a nuclear power plant, is done in various steps. An overview of the methods, used in each of these steps will be given in the following chapters: Seismic analysis of the buildings taking into account structures with important mass or stiffness. The input to the building analysis, called ground motion, is described by an accelerogram or a response spectra. In this step, soil structure interaction has to be taken into account. Various methods are available: Impedance, finite element. The response of the structure can be calculated by spectral method or by time history analysis; advantages and limitations of each method will be shown. Calculation of floor response spectrum which are the data for the equipment analysis. Methods to calculate this spectrum will be described. Seismic analysis of the equipments. Presentation of the methods for both monosupported and multisupported equipment will be given. In addition methods to analyse equipments which present non-linearities associated to the boundary conditions such as impacts, sliding will be presented. (author). 30 refs, 15 figs

  19. Source modelling in seismic risk analysis for nuclear power plants

    International Nuclear Information System (INIS)

    Yucemen, M.S.

    1978-12-01

    The proposed probabilistic procedure provides a consistent method for the modelling, analysis and updating of uncertainties that are involved in the seismic risk analysis for nuclear power plants. The potential earthquake activity zones are idealized as point, line or area sources. For these seismic source types, expressions to evaluate their contribution to seismic risk are derived, considering all the possible site-source configurations. The seismic risk at a site is found to depend not only on the inherent randomness of the earthquake occurrences with respect to magnitude, time and space, but also on the uncertainties associated with the predicted values of the seismic and geometric parameters, as well as the uncertainty in the attenuation model. The uncertainty due to the attenuation equation is incorporated into the analysis through the use of random correction factors. The influence of the uncertainty resulting from the insufficient information on the seismic parameters and source geometry is introduced into the analysis by computing a mean risk curve averaged over the various alternative assumptions on the parameters and source geometry. Seismic risk analysis is carried for the city of Denizli, which is located in the seismically most active zone of Turkey. The second analysis is for Akkuyu

  20. Public speaking in front of an unreceptive audience increases implicit power motivation and its endocrine arousal signature.

    Science.gov (United States)

    Wiemers, Uta S; Schultheiss, Oliver C; Wolf, Oliver T

    2015-05-01

    The present study explored the motivational characteristics of the Trier Social Stress Test (TSST; Kirschbaum, Pirke, & Hellhammer, 1993). Seventy-two participants either completed the public-speaking component of the TSST or, as a control condition, the friendly TSST (Wiemers, Schoofs, & Wolf, 2013) and wrote picture stories both before and after treatment. Stories were coded for motivational imagery related to power, achievement, and affiliation as well as for activity inhibition, a marker of functional brain lateralization during stress. The TSST had a specific arousing effect on power motivation, but not on other motivational needs, on activity inhibition, or on story length. TSST-elicited increases in power imagery, but not in achievement or affiliation imagery, were associated with a relatively greater salivary alpha-amylase response and with a relatively lesser salivary cortisol response. These findings suggest that the TSST specifically induces power-related stress. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Procedure for the analysis of errors of commission during non-power modes of nuclear power plant operation

    International Nuclear Information System (INIS)

    Julius, J.A.; Jorgenson, E.J.; Parry, G.W.; Mosleh, A.M.

    1996-01-01

    The continued, historical occurrence of human interactions which place nuclear power plants in a condition of potentially heightened risk is of increasing interest to regulators, utility management, and industry observers alike. These Errors of Commission (EOCs), as they are often called, lead to a variety of questions such as: 'Can the event lead to a potentially dangerous condition such as core damage? By what failure mechanisms? With what frequency? What defences does the plant have to mitigate the event? Are these actions in the Probabilistic Risk Assessment (PRA) model of the plant?'. EOCs are often excluded from the bounds of a typical PRA model, yet they have the potential for being significant contributors to risk. This paper is the second of two describing procedures for the analysis of the potential for significant errors of commission. The first paper addressed operations at power while this paper describes the procedure for non-power operations. Each procedure describes a method for identifying the opportunities for error, identifying failures modes of functions, systems, or components that could arise from such errors (referred to in this paper as error expressions), and the identification of the most significant of these EOCs based on consideration of consequences, recovery potential, and likelihood

  2. Prolonged Living as a Refugee from the Area Around a Stricken Nuclear Power Plant Increases the Risk of Death.

    Science.gov (United States)

    Tanaka, Reiichiro

    2015-08-01

    Although it is well known that the Great East Japan Earthquake (March 11, 2011) resulted in a large number of disaster-related deaths, it is not common knowledge that the number of disaster-related deaths continues to increase, even four years after the earthquake, in Fukushima Prefecture, where the nuclear power plant accident occurred. There has been a lack of a minute and critical analysis for the causes for this continuous increase. In this report, the causes for the increase in disaster-related deaths in Fukushima Prefecture were analyzed by aggregating and comparing multiple data released by public organizations (the Reconstruction Agency, the National Police Agency, and Fukushima Prefecture), which may also have implications for developing response strategies to other disasters. The disaster-related death rate, the dead or missing rate, and the refugee rate (the number of disaster-related deaths, dead or missing persons, and refugees per 1,000 people) in each prefecture in stricken areas, and also each city, county, town, and village in Fukushima Prefecture, were calculated and compared with each other. The populations which were used for the calculation of each death rate in the area were based on the number of dead victims who had lived in the area when the earthquake occurred, regardless of where they were at the time of their death. The disaster-related death rate was higher than the dead or missing rate in the area around a stricken nuclear power plant in Fukushima Prefecture. These areas coincide exactly with the Areas under Evacuation Orders because of unsafe radiation levels. The external and internal radiation doses of most of the victims of the Great East Japan Earthquake have appeared not to be so high to harm their health, until now. The psychological stress associated with being displaced from one's home for a long time with an uncertain future may be the cause for these disaster-related deaths. There is an urgent need to recognize refugees

  3. Can the Critical Power Model Explain the Increased Peak Velocity/Power During Incremental Test After Concurrent Strength and Endurance Training?

    Science.gov (United States)

    Denadai, Benedito S; Greco, Camila C

    2017-08-01

    Denadai, BS and Greco, CC. Can the critical power model explain the increased peak velocity/power during incremental test after concurrent strength and endurance training? J Strength Cond Res 31(8): 2319-2323, 2017-The highest exercise intensity that can be maintained at the end of a ramp or step incremental test (i.e., velocity or work rate at V[Combining Dot Above]O2max - Vpeak/Wpeak) can be used for endurance performance prediction and individualization of aerobic training. The interindividual variability in Vpeak/Wpeak has been attributed to exercise economy, anaerobic capacity, and neuromuscular capability, alongside the major determinant of aerobic capacity. Interestingly, findings after concurrent strength and endurance training performed by endurance athletes have challenged the actual contribution of these variables. The critical power model usually derived from the performance of constant-work rate exercise can also explain tolerance to a ramp incremental exercise so that, Vpeak/Wpeak can be predicted accurately. However, there is not yet discussion of possible concomitant improvements in the parameters of the critical power model and Vpeak/Wpeak after concurrent training and whether they can be associated with and therefore depend on different neuromuscular adaptations. Therefore, this brief review presents some evidence that the critical power model could explain the improvement of Vpeak/Wpeak and should be used to monitor aerobic performance enhancement after different concurrent strength- and endurance-training designs.

  4. Analysis of Indentation-Derived Power-Law Creep Response

    Science.gov (United States)

    Martinez, Nicholas J.; Shen, Yu-Lin

    2016-03-01

    The use of instrumented indentation to characterize power-law creep is studied by computational modeling. Systematic finite element analyses were conducted to examine how indentation creep tests can be employed to retrieve the steady-state creep parameters pertaining to regular uniaxial loading. The constant indentation load hold and constant indentation-strain-rate methods were considered, first using tin (Sn)-based materials as a model system. The simulated indentation-strain rate-creep stress relations were compared against the uniaxial counterparts serving as model input. It was found that the constant indentation-strain-rate method can help establish steady-state creep, and leads to a more uniform behavior than the constant-load hold method. An expanded parametric analysis was then performed using the constant indentation-strain-rate method, taking into account a wide range of possible power-law creep parameters. The indentation technique was found to give rise to accurate stress exponents, and a certain trend for the ratio between indentation strain rate and uniaxial strain rate was identified. A contour-map representation of the findings serves as practical guidance for determining the uniaxial power-law creep response based on the indentation technique.

  5. Regression and kriging analysis for grid power factor estimation

    Directory of Open Access Journals (Sweden)

    Rajesh Guntaka

    2014-12-01

    Full Text Available The measurement of power factor (PF in electrical utility grids is a mainstay of load balancing and is also a critical element of transmission and distribution efficiency. The measurement of PF dates back to the earliest periods of electrical power distribution to public grids. In the wide-area distribution grid, measurement of current waveforms is trivial and may be accomplished at any point in the grid using a current tap transformer. However, voltage measurement requires reference to ground and so is more problematic and measurements are normally constrained to points that have ready and easy access to a ground source. We present two mathematical analysis methods based on kriging and linear least square estimation (LLSE (regression to derive PF at nodes with unknown voltages that are within a perimeter of sample nodes with ground reference across a selected power grid. Our results indicate an error average of 1.884% that is within acceptable tolerances for PF measurements that are used in load balancing tasks.

  6. Profitability primer: a guide to profitability analysis in the electric power industry

    International Nuclear Information System (INIS)

    Woo, C.K.; Lloyd-Zannetti, D.; Martin, J.; Price, S.

    1996-06-01

    As the electric power industry is opened to forces of competition, increased attention must be focused to develop products and services that deliver good value to customers and to identify customer segments that are profitable to serve. This primer introduces the concept of profitability analysis and its application to the electric power industry. The primer recognizes that some segments of the business will remain monopolistic and subject to regulations, while other segments will become competitive. The primer also recognizes that customer profitability is critically dependent on a host of related issues such as how internal costs are allocated to various functions and how revenues are collected and allocated

  7. Family nurture intervention in preterm infants increases early development of cortical activity and independence of regional power trajectories.

    Science.gov (United States)

    Welch, Martha G; Stark, Raymond I; Grieve, Philip G; Ludwig, Robert J; Isler, Joseph R; Barone, Joseph L; Myers, Michael M

    2017-12-01

    Premature delivery and maternal separation during hospitalisation increase infant neurodevelopmental risk. Previously, a randomised controlled trial of Family Nurture Intervention (FNI) in the neonatal intensive care unit demonstrated improvement across multiple mother and infant domains including increased electroencephalographic (EEG) power in the frontal polar region at term age. New aims were to quantify developmental changes in EEG power in all brain regions and frequencies and correlate developmental changes in EEG power among regions. EEG (128 electrodes) was obtained at 34-44 weeks postmenstrual age from preterm infants born 26-34 weeks. Forty-four infants were treated with Standard Care and 53 with FNI. EEG power was computed in 10 frequency bands (1-48 Hz) in 10 brain regions and in active and quiet sleep. Percent change/week in EEG power was increased in FNI in 132/200 tests (p < 0.05), 117 tests passed a 5% False Discovery Rate threshold. In addition, FNI demonstrated greater regional independence in those developmental rates of change. This study strengthens the conclusion that FNI promotes cerebral cortical development of preterm infants. The findings indicate that developmental changes in EEG may provide biomarkers for risk in preterm infants as well as proximal markers of effects of FNI. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  8. Increased power generation from primary sludge by a submersible microbial fuel cell and optimum operational conditions

    DEFF Research Database (Denmark)

    Vologni, Valentina; Kakarla, Ramesh; Angelidaki, Irini

    2013-01-01

    Microbial fuel cells (MFCs) have received attention as a promising renewable energy technology for waste treatment and energy recovery. We tested a submersible MFC with an innovative design capable of generating a stable voltage of 0.250 ± 0.008 V (with a fixed 470 Ω resistor) directly from primary...... sludge. In a polarization test, the maximum power density was 0.18 W/m2 at a current density of 0.8 A/m2 with an external resistor of 300 Ω. The anodic solution of the primary sludge needs to be adjusted to a pH 7 for high power generation. The modified primary sludge with an added phosphate buffer...

  9. High-resolution Fourier transform ion cyclotron resonance mass spectrometry with increased throughput for biomolecular analysis.

    Science.gov (United States)

    Nagornov, Konstantin O; Gorshkov, Mikhail V; Kozhinov, Anton N; Tsybin, Yury O

    2014-09-16

    A multielectrode ion cyclotron resonance (ICR) cell, herein referred to as the "4X cell", for signal detection at the quadruple frequency multiple was implemented and characterized on a commercial 10 T Fourier transform ICR mass spectrometer (FT-ICR MS). Notably, with the 4X cell operating at a 10 T magnetic field we achieved a 4-fold increase in MS acquisition rate per unit of resolving power for signal detection periods typically employed in FTMS, viz., shorter than 6 s. Effectively, the obtained resolution performance represents the limit of the standard measurement principle with dipolar signal detection and FT signal processing at an equivalent magnetic field of 40 T. In other words, the achieved resolving powers are 4 times higher than those provided by 10 T FT-ICR MS with a standard ICR cell. For example, resolving powers of 170,000 and 70,000 were obtained in magnitude-mode Fourier spectra of 768 and 192 ms apodized transient signals acquired for a singly charged fluorinated phosphazine (m/z 1422) and a 19-fold charged myoglobin (MW 16.9 kDa), respectively. In peptide analysis, the baseline-resolved isotopic fine structures were obtained with as short as 768 ms transients. In intact protein analysis, the average resolving power of 340,000 across the baseline-resolved (13)C isotopic pattern of multiply charged ions of bovine serum albumin was obtained with 1.5 s transients. The dynamic range and the mass measurement accuracy of the 4X cell were found to be comparable to the ones obtained for the standard ICR cell on the same mass spectrometer. Overall, the reported results validate the advantages of signal detection at frequency multiples for increased throughput in FT-ICR MS, essential for numerous applications with time constraints, including proteomics.

  10. New inspection and reconstitution techniques for fuel assemblies increase power plants efficiency

    International Nuclear Information System (INIS)

    Knecht, K.

    1998-01-01

    The amount of time required to complete many nuclear fuel service activities can be cut significantly through the use of innovative procedures and equipment. In addition to other benefits, these new approaches lower the radiation exposure of service and plant personnel. These new procedures and hardware can be integrated into the power plant processes and equipment to more effectively complete the required service activities. (author)

  11. HIIT produces increases in muscle power and free testosterone in male masters athletes

    OpenAIRE

    Herbert, P; Hayes, LD; Sculthorpe, NF; Grace, FM

    2017-01-01

    High intensity interval training (HIIT) improves peak power output (PPO) in sedentary aging men but has not been examined in masters endurance athletes. Therefore, we investigated whether a 6-week programme of low volume HIIT would (i) improve PPO in masters athletes and (ii) whether any change in PPO would be associated with steroid hormone perturbations.Seventeen male masters athletes (60 ± 5 years) completed the intervention which comprised of nine HIIT sessions over six weeks. HIIT sessio...

  12. Expanding exports, increasing smog : Ontario Power Generation's and Hydro One's strategies to continue coal-fired electricity generation in Ontario

    International Nuclear Information System (INIS)

    Gibbons, J.

    2002-06-01

    The production of coal-fired electricity increased by approximately 150 per cent in Ontario between 1995 and 2000. As a result, the smog-causing emissions generated by the five coal-fired power plants operated by Ontario Power Generation caused an increase in smog and worsened air quality in the province as well as affecting air quality as far afield as the Atlantic provinces. Between 2002 and 2005, it is expected that the Pickering and Bruce nuclear plants will be returned to service, making the electricity generated by the coal plants surplus to Ontario's needs. Increasing this surplus are the planned natural gas generating stations. Ontario Power Generation is planning on using this surplus to export it to the United States rather than phasing out its reliance on coal. The increase in exports to the United States Northeast and Midwest is planned with Hydro One, already busy increasing its transmission capacity to the United States by 1,000 megawatt (MW). This plan involves laying 975 MW submarine cable from the Nanticoke Generating Station (operated by Ontario Power Generation) under Lake Erie to Pennsylvania, Ohio, or both states. At the moment, the exports are constrained by the government emissions limits imposed by the Ontario government on sulphur dioxide and nitrogen oxides. This constraint could be removed if Ontario Power Generation decides to pay further for pollution controls for sulphur dioxide and nitrogen oxides at its coal stations. Unfortunately, increasing the exports would also result in emissions increases for 28 other uncapped pollutants such as lead, mercury and arsenic. The author recommended that the Ontario government ban non-emergency coal-fired electricity exports to improve air quality in the province. refs., 8 figs

  13. Health effects models for nuclear power plant accident consequence analysis

    International Nuclear Information System (INIS)

    Abrahamson, S.; Bender, M.A.; Boecker, B.B.; Scott, B.R.

    1993-05-01

    The Nuclear Regulatory Commission (NRC) has sponsored several studies to identify and quantify, through the use of models, the potential health effects of accidental releases of radionuclides from nuclear power plants. The Reactor Safety Study provided the basis for most of the earlier estimates related to these health effects. Subsequent efforts by NRC-supported groups resulted in improved health effects models that were published in the report entitled open-quotes Health Effects Models for Nuclear Power Plant Consequence Analysisclose quotes, NUREG/CR-4214, 1985 and revised further in the 1989 report NUREG/CR-4214, Rev. 1, Part 2. The health effects models presented in the 1989 NUREG/CR-4214 report were developed for exposure to low-linear energy transfer (LET) (beta and gamma) radiation based on the best scientific information available at that time. Since the 1989 report was published, two addenda to that report have been prepared to (1) incorporate other scientific information related to low-LET health effects models and (2) extend the models to consider the possible health consequences of the addition of alpha-emitting radionuclides to the exposure source term. The first addendum report, entitled open-quotes Health Effects Models for Nuclear Power Plant Accident Consequence Analysis, Modifications of Models Resulting from Recent Reports on Health Effects of Ionizing Radiation, Low LET Radiation, Part 2: Scientific Bases for Health Effects Models,close quotes was published in 1991 as NUREG/CR-4214, Rev. 1, Part 2, Addendum 1. This second addendum addresses the possibility that some fraction of the accident source term from an operating nuclear power plant comprises alpha-emitting radionuclides. Consideration of chronic high-LET exposure from alpha radiation as well as acute and chronic exposure to low-LET beta and gamma radiations is a reasonable extension of the health effects model

  14. Aerospace Power Systems Design and Analysis (APSDA) Tool

    Science.gov (United States)

    Truong, Long V.

    1998-01-01

    The conceptual design of space and/or planetary electrical power systems has required considerable effort. Traditionally, in the early stages of the design cycle (conceptual design), the researchers have had to thoroughly study and analyze tradeoffs between system components, hardware architectures, and operating parameters (such as frequencies) to optimize system mass, efficiency, reliability, and cost. This process could take anywhere from several months to several years (as for the former Space Station Freedom), depending on the scale of the system. Although there are many sophisticated commercial software design tools for personal computers (PC's), none of them can support or provide total system design. To meet this need, researchers at the NASA Lewis Research Center cooperated with Professor George Kusic from the University of Pittsburgh to develop a new tool to help project managers and design engineers choose the best system parameters as quickly as possible in the early design stages (in days instead of months). It is called the Aerospace Power Systems Design and Analysis (APSDA) Tool. By using this tool, users can obtain desirable system design and operating parameters such as system weight, electrical distribution efficiency, bus power, and electrical load schedule. With APSDA, a large-scale specific power system was designed in a matter of days. It is an excellent tool to help designers make tradeoffs between system components, hardware architectures, and operation parameters in the early stages of the design cycle. user interface. It operates on any PC running the MS-DOS (Microsoft Corp.) operating system, version 5.0 or later. A color monitor (EGA or VGA) and two-button mouse are required. The APSDA tool was presented at the 30th Intersociety Energy Conversion Engineering Conference (IECEC) and is being beta tested at several NASA centers. Beta test packages are available for evaluation by contacting the author.

  15. Analysis of Highly Wind Power Integrated Power System model performance during Critical Weather conditions

    DEFF Research Database (Denmark)

    Basit, Abdul; Hansen, Anca Daniela; Sørensen, Poul Ejnar

    2014-01-01

    Secure power system operation of a highly wind power integrated power system is always at risk during critical weather conditions, e.g. in extreme high winds. The risk is even higher when 50% of the total electricity consumption has to be supplied by wind power, as the case for the future Danish...

  16. Thermodynamic analysis of a new combined cooling and power system using ammonia–water mixture

    International Nuclear Information System (INIS)

    Wang, Jiangfeng; Wang, Jianyong; Zhao, Pan; Dai, Yiping

    2016-01-01

    Highlights: • A new combined cooling and power system is proposed. • Exergy destruction analysis is used to identify irreversibility of components in system. • Thermodynamic parameter analysis is performed for system. - Abstract: In order to achieve both power and cooling supply for users, a new combined cooling and power system using ammonia–water mixture is proposed to utilizing low grade heat sources, such as industrial waste heat, solar energy and geothermal energy. The proposed system combines a Kalina cycle and an ammonia–water absorption refrigeration cycle, in which the ammonia–water turbine exhaust is delivered to a separator to extract purer ammonia vapor. The purer ammonia vapor enters an evaporator to generate refrigeration output after being condensed and throttled. Mathematical models are established to simulate the combined system under steady-state conditions. Exergy destruction analysis is conducted to display the exergy destruction distribution in the system qualitatively and the results show that the major exergy destruction occurs in the heat exchangers. Finally a thermodynamic sensitivity analysis is performed and reveals that with an increase in the pressure of separator I or the ammonia mass fraction of basic solution, thermal efficiency and exergy efficiency of the system increase, whereas with an increase in the temperature of separator I, the ammonia–water turbine back pressure or the condenser II pressure, thermal efficiency and exergy efficiency of the system drop.

  17. Local structure analysis of materials for increased energy efficiency

    Science.gov (United States)

    Medling, Scott

    In this dissertation, a wide range of materials which exhibit interesting properties with potential for energy efficiency applications are investigated. The bulk of the research was conducted using the Extended X-ray Absorption Fine Structure (EXAFS) technique. EXAFS is a powerful tool for elucidating the local structure of novel materials, and it's advantages are presented in Chapter 2. In Chapter 3, I present details on two new techniques which are used in studies later in this dissertation, but are also promising for other, unrelated studies and, therefore, warrant being discussed generally. I explain the presence of and present a method for subtracting the X-ray Raman background in the fluorescence window when collecting fluorescence EXAFS data of a dilute dopant Z in a Z+1 host. I introduce X-ray magnetic circular dichroism (XMCD) and discuss the process to reduce XMCD data, including the self-absorption corrections for low energy K-edges. In Chapter 4, I present a series of investigations on ZnS:Cu electroluminescent phosphors. Optical microscopy indicates that the emission centers do not degrade uniformly or monotonically, but rather, most of the emission centers blink on and off during degradation. The effect of this on various proposed degradation mechanisms is discussed. EXAFS data of ZnS:Cu phosphors ground to enable thinner, lower-voltage devices indicate that grinding preferentially causes damage to the CuS nanoprecipitates, quenching electroluminescence (EL) and concluding that smaller particles must be built up from nanoparticles instead. EXAFS data of nanoparticles show that adding a ZnS shell outside a ZnS:Cu core provides significant additional encapsulation of the Cu, increasing photoluminescence and indicating that this may increase EL if devices can be fabricated. Data from extremely dilute (0.02% Cu) ZnS:Cu nanoparticles is presented in order to specifically study the non-precipitate and suggests that the Cu dopant substitutes for Zn and is

  18. Power analysis and simulation of a vehicle under combined loads

    International Nuclear Information System (INIS)

    Khayyam, H.; Kouzani, A.Z.; Khoshmanesh, K.; Hu, E.

    2008-01-01

    Reducing fuel consumption in vehicles offers many obvious economic benefits, and also helps reduce air pollution emission levels. Mechanical engineers and automotive researches have continuously searched for ways to optimize fuel consumption in vehicles. This paper presented an analytical model of fuel consumption (AMFC) in an effort to coordinate the driving power and manage the overall fuel consumption for an internal combustion engine vehicle. The model calculated the different loads applied on the vehicle, such as road-slope, road-friction, wind-drag, accessories, and mechanical losses. It also solved the combustion equation of the engine under different working conditions including various fuel compositions, excess airs and air inlet temperatures. The model then determined the contribution of each load to signify the energy distribution and power flows of the vehicle. In order to assess the model's sensitivity to different loads, the following four simulations were conducted: flat-windless, flat-windy, sloppy-windless, sloppy-windy. The average fuel consumption for the four simulations was presented. The paper outlined the specification of the vehicle and environment as well as the simulation methodology. The model, algorithm, slope simulation, and drive strategy were presented. It was concluded that the power consumption significantly increased where the slope friction came into play and that the model has the potential to assist in vehicle energy management. 16 refs., 4 tabs., 14 figs

  19. Exergoeconomical analysis of coal gasification combined cycle power plants

    International Nuclear Information System (INIS)

    Avgousti, A.; Knoche, K.F.; Poptodorov, H.; Hesselmann, K.; Roth, M.

    1989-01-01

    This paper reports on combined cycle power plants with integrated coal gasification for a better utilization of primary energy sources which gained more and more importance. The established coal gasification technology offers various possibilities e.g. the TEXACO or the PRENFLO method. Recommendation for processes with these gasification methods will be evaluated energetically and exergetically. The pure thermodynamical analysis is at a considerable disadvantage in that the economical consequences of certain process improvement measures are not subjected to investigation. The connection of the exergetical with the economical evaluation will be realized in a way suggested as exergoeconomical analysis. This consideration of the reciprocal influencing of the exergy destruction and the capital depending costs is resulting in an optimization of the process and a minimization of the product costs

  20. Uncertainty propagation in probabilistic safety analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Fleming, P.V.

    1981-09-01

    The uncertainty propagation in probabilistic safety analysis of nuclear power plants, is done. The methodology of the minimal cut is implemented in the computer code SVALON and the results for several cases are compared with corresponding results obtained with the SAMPLE code, which employs the Monte Carlo method to propagate the uncertanties. The results have show that, for a relatively small number of dominant minimal cut sets (n approximately 25) and error factors (r approximately 5) the SVALON code yields results which are comparable to those obtained with SAMPLE. An analysis of the unavailability of the low pressure recirculation system of Angra 1 for both the short and long term recirculation phases, are presented. The results for the short term phase are in good agreement with the corresponding one given in WASH-1400. (E.G.) [pt

  1. GNSS Spoofing Detection Based on Signal Power Measurements: Statistical Analysis

    Directory of Open Access Journals (Sweden)

    V. Dehghanian

    2012-01-01

    Full Text Available A threat to GNSS receivers is posed by a spoofing transmitter that emulates authentic signals but with randomized code phase and Doppler values over a small range. Such spoofing signals can result in large navigational solution errors that are passed onto the unsuspecting user with potentially dire consequences. An effective spoofing detection technique is developed in this paper, based on signal power measurements and that can be readily applied to present consumer grade GNSS receivers with minimal firmware changes. An extensive statistical analysis is carried out based on formulating a multihypothesis detection problem. Expressions are developed to devise a set of thresholds required for signal detection and identification. The detection processing methods developed are further manipulated to exploit incidental antenna motion arising from user interaction with a GNSS handheld receiver to further enhance the detection performance of the proposed algorithm. The statistical analysis supports the effectiveness of the proposed spoofing detection technique under various multipath conditions.

  2. TREEFINDER: a powerful graphical analysis environment for molecular phylogenetics

    Directory of Open Access Journals (Sweden)

    von Haeseler Arndt

    2004-06-01

    Full Text Available Abstract Background Most analysis programs for inferring molecular phylogenies are difficult to use, in particular for researchers with little programming experience. Results TREEFINDER is an easy-to-use integrative platform-independent analysis environment for molecular phylogenetics. In this paper the main features of TREEFINDER (version of April 2004 are described. TREEFINDER is written in ANSI C and Java and implements powerful statistical approaches for inferring gene tree and related analyzes. In addition, it provides a user-friendly graphical interface and a phylogenetic programming language. Conclusions TREEFINDER is a versatile framework for analyzing phylogenetic data across different platforms that is suited both for exploratory as well as advanced studies.

  3. Increasing the time resolution of a pulse width modulator in a class D power amplifier by using delay lines

    Science.gov (United States)

    Weber, M.; Vennemann, T.; Mathis, W.

    2014-11-01

    In this paper, we present a method to increase the time resolution of a pulse width modulator by using delay lines. The modulator is part of an open loop class D power amplifier, which uses the ZePoC algorithm to code the audio signal which is amplified in the class D power stage. If the time resolution of the pulse width modulator is high enough, ZePoC could also be used to build an high accuracy AC power standard, because of its open loop property. With the presented method the time resolution theoretically could be increased by a factor of 16, which means here the time resolution will be enhanced from 5 ns to 312.5 ps.

  4. Power Estimation for Gene-Longevity Association Analysis Using Concordant Twins

    Directory of Open Access Journals (Sweden)

    Qihua Tan

    2014-01-01

    Full Text Available Statistical power is one of the major concerns in genetic association studies. Related individuals such as twins are valuable samples for genetic studies because of their genetic relatedness. Phenotype similarity in twin pairs provides evidence of genetic control over the phenotype variation in a population. The genetic association study on human longevity, a complex trait that is under control of both genetic and environmental factors, has been confronted by the small sample sizes of longevity subjects which limit statistical power. Twin pairs concordant for longevity have increased probability for carrying beneficial genes and thus are useful samples for gene-longevity association analysis. We conducted a computer simulation to estimate the power of association study using longevity concordant twin pairs. We observed remarkable power increases in using singletons from longevity concordant twin pairs as cases in comparison with cases of sporadic proband. A similar power would require doubled sample sizes for fraternal twins than for identical twins who are concordant for longevity suggesting that longevity concordant identical twins are more efficient samples than fraternal twins. We also observed an approximate of 2- to 3-fold increase in sample sizes needed for longevity cutoff at age 90 as compared with that at age 95. Overall, our results showed high value of twins in genetic association studies on human longevity.

  5. Quantum heat engine power can be increased by noise-induced coherence.

    Science.gov (United States)

    Scully, Marlan O; Chapin, Kimberly R; Dorfman, Konstantin E; Kim, Moochan Barnabas; Svidzinsky, Anatoly

    2011-09-13

    Laser and photocell quantum heat engines (QHEs) are powered by thermal light and governed by the laws of quantum thermodynamics. To appreciate the deep connection between quantum mechanics and thermodynamics we need only recall that in 1901 Planck introduced the quantum of action to calculate the entropy of thermal light, and in 1905 Einstein's studies of the entropy of thermal light led him to introduce the photon. Then in 1917, he discovered stimulated emission by using detailed balance arguments. Half a century later, Scovil and Schulz-DuBois applied detailed balance ideas to show that maser photons were produced with Carnot quantum efficiency (see Fig. 1A). Furthermore, Shockley and Quiesser invoked detailed balance to obtain the efficiency of a photocell illuminated by "hot" thermal light (see Fig. 2A). To understand this detailed balance limit, we note that in the QHE, the incident light excites electrons, which can then deliver useful work to a load. However, the efficiency is limited by radiative recombination in which the excited electrons are returned to the ground state. But it has been proven that radiatively induced quantum coherence can break detailed balance and yield lasing without inversion. Here we show that noise-induced coherence enables us to break detailed balance and get more power out of a laser or photocell QHE. Surprisingly, this coherence can be induced by the same noisy (thermal) emission and absorption processes that drive the QHE (see Fig. 3A). Furthermore, this noise-induced coherence can be robust against environmental decoherence.Fig. 1.(A) Schematic of a laser pumped by hot photons at temperature T(h) (energy source, blue) and by cold photons at temperature T(c) (entropy sink, red). The laser emits photons (green) such that at threshold the laser photon energy and pump photon energy is related by Carnot efficiency (4). (B) Schematic of atoms inside the cavity. Lower level b is coupled to the excited states a and β. The laser power

  6. WORK AND POWER ANALYSIS OF THE GOLF SWING

    Directory of Open Access Journals (Sweden)

    Steven M. Nesbit

    2005-12-01

    Full Text Available A work and power (energy analysis of the golf swing is presented as a method for evaluating the mechanics of the golf swing. Two computer models were used to estimate the energy production, transfers, and conversions within the body and the golf club by employing standard methods of mechanics to calculate work of forces and torques, kinetic energies, strain energies, and power during the golf swing. A detailed model of the golf club determined the energy transfers and conversions within the club during the downswing. A full-body computer model of the golfer determined the internal work produced at the body joints during the downswing. Four diverse amateur subjects were analyzed and compared using these two models. The energy approach yielded new information on swing mechanics, determined the force and torque components that accelerated the club, illustrated which segments of the body produced work, determined the timing of internal work generation, measured swing efficiencies, calculated shaft energy storage and release, and proved that forces and range of motion were equally important in developing club head velocity. A more comprehensive description of the downswing emerged from information derived from an energy based analysis

  7. Force analysis of magnetic bearings with power-saving controls

    International Nuclear Information System (INIS)

    Johnson, D.; Brown, G.V.; Inman, D.J.

    1992-01-01

    Most magnetic bearing control schemes use a bias current with a superimposed control current to linearize the relationship between the control current and the force it delivers. For most operating conditions, the existence of the bias current requires more power than alternative methods that do not use conventional bias. Two such methods are examined which diminish or eliminate bias current. In the typical bias control scheme it is found that for a harmonic control force command into a voltage limited transconductance amplifier, the desired force output is obtained only up to certain combinations of force amplitude and frequency. Above these values, the force amplitude is reduced and a phase lag occurs. The power saving alternative control schemes typically exhibit such deficiencies at even lower command frequencies and amplitudes. To assess the severity of these effects, a time history analysis of the force output is performed for the bias method and the alternative methods. Results of the analysis show that the alternative approaches may be viable. The various control methods examined were mathematically modeled using nondimensionalized variables to facilitate comparison of the various methods

  8. Analysis of color environment in nuclear power plants

    International Nuclear Information System (INIS)

    Natori, Kazuyuki; Akagi, Ichiro; Souma, Ichiro; Hiraki, Tadao; Sakurai, Yukihiro.

    1996-01-01

    This article reports the results of color and psychological analysis of the outlook of nuclear power plants and the visual environments inside of the plants. Study one was the color measurements of the outlook of nuclear plants and the visual environment inside of the plants. Study two was a survey of the impressions on the visual environments of nuclear plants obtained from observers and interviews of the workers. Through these analysis, we have identified the present state of, and the problems of the color environments of the nuclear plants. In the next step, we have designed the color environments of inside and outside of the nuclear plants which we would recommend (inside designs were about fuel handling room, operation floor of turbine building, observers' pathways, central control room, rest room for the operators). Study three was the survey about impressions on our design inside and outside of the nuclear plants. Nuclear plant observers, residents in Osaka city, residents near the nuclear plants, the operators, employees of subsidiary company and the PR center guides rated their impressions on the designs. Study four was the survey about the design of the rest room for the operators controlling the plants. From the results of four studies, we have proposed some guidelines and problems about the future planning about the visual environments of nuclear power plants. (author)

  9. Application and development analysis of nuclear power plant modular construction

    International Nuclear Information System (INIS)

    Fang Xiaopeng

    2015-01-01

    Modular Construction is currently one of the major development trends for the nuclear power plant construction technology worldwide. In the first-of-a-kind AP1000 Nuclear Power Project practiced in China, the large-scale structural modules and mechanical modules have been successfully fabricated, assembled and installed. However, in the construction practice of the project, some quality issues are identified with the assembly and installation process of large-scale structural modules in addition to the issue of incomplete supply of mechanical modules, which has failed to fully demonstrate the features and merits of modular construction. This paper collects and consolidates the issues of modular construction of AP1000 first of a kind reactor, providing root cause analysis in the aspects of process design, quality control, site construction logic, interface management in the process of module fabrication, assembly and installation; modular construction feasibility assessment index is proved based on the quantification and qualitative analysis of the impact element. Based on the modular construction feasibility, NPP modular construction improvement suggestions are provided in the aspect of modular assembly optimization definition, tolerance control during the fitting process and the construction logic adjustment. (author)

  10. Transient thermal analysis of a space reactor power system

    International Nuclear Information System (INIS)

    Gaeta, M.J.; Best, F.R.

    1993-01-01

    Space nuclear power systems utilize materials and processes that are completely different from terrestrial reactor systems. Therefore, the tools used to analyze ground-based systems are inappropriate for space reactor design and analysis. The purpose of this study was to develop a space reactor transient analysis tool and to apply this tool to scenarios of interest. The scope of the simulation includes the thermal and neutronic behavior of a liquid-metal-cooled fast reactor, the electrical and thermal performance of the thermoelectric generators, the thermal dynamics of heat pipe radiators, and the thermal behavior of the coolant piping between major components. The thermal model of the system is explicitly coupled to a momentum model of the primary and secondary coolant loops. A one-dimensional conduction model is employed in all solid component models. The reactor model includes an expression for energy generation due to fission and decay heat. The thermoelectric heat exchanger model accounts for thermal energy conversion to useful electrical output. The two-node radiator heat pipe model includes normal operation as well as limited heat pipe operation under sonic limit conditions. The reactor, thermoelectric heat exchanger, and heat pipe models are coupled explicitly by the coolant piping thermal model. The computer program is used to simulate a variety of transients including reactor power changer, degradation of the radiator, and a temporary open circuit condition on the thermoelectrics

  11. Exergy analysis of a combined heat and power plant with integrated lignocellulosic ethanol production

    DEFF Research Database (Denmark)

    Lythcke-Jørgensen, Christoffer Ernst; Haglind, Fredrik; Clausen, Lasse Røngaard

    2013-01-01

    Integrating second generation bioethanol production in combined heat and power units is expected to increase system energy efficiencies while producing sustainable fuel for the transportation sector at a competitive price. By applying exergy analysis, this study assessed the efficiency of an inte......Integrating second generation bioethanol production in combined heat and power units is expected to increase system energy efficiencies while producing sustainable fuel for the transportation sector at a competitive price. By applying exergy analysis, this study assessed the efficiency...... of an integrated system in which steam extracted from an existing combined heat and power unit is used for covering the heating demand of a lignocellulosic ethanol production facility. The integration solution was designed and optimized using already existing steam extraction points in the combined heat and power...... and losses in the system was in the range of 0.46-0.87 depending on the system operation. This study suggests that a well-designed heat integration network can increase the exergy efficiency of the integrated system markedly....

  12. Are Public-Private Partnerships an Appropriate Governance Structure for Power Plants? A Transaction Cost Analysis

    Science.gov (United States)

    Ho, S. Ping; Hsu, Yaowen

    2015-04-01

    In order to meet the requirements of the rapid economic growth, many countries demand an increasing number of power plants to meet the increasing electricity usage. Since high capital requirements of power plants present a big issue for these countries, PPPs have been considered an alternative to provide power plant infrastructure. In particular, in emerging or developing countries, PPPs may be the fastest way to provide the infrastructure needed. However, while PPPs are a promising alternative to providing various types of infrastructure, many failed power plant PPP projects have made it evident that PPPs, under certain situations, can be very costly or even a wrong choice of governance structure. While the higher efficiency due to better pooling of resources is greatly emphasized in Public-Private Partnerships (PPPs), the embedded transaction inefficiencies are often understated or even ignored. Through the lens of Transaction Cost Economics (TCE), this paper aims to answer why and when PPPs may become a costly governance structure for power plants. Specifically, we develop a TCE-based theory of PPPs as a governance structure. This theory suggests that three major opportunism problems embedded in infrastructure PPPs are possible to cause substantial transaction costs and render PPPs a costly governance structure. The three main opportunism problems are principal-principal problem, firm's hold-up problem, and government-led hold-up problem. Moreover, project and institutional characteristics that may lead to opportunism problems are identified. Based on these characteristics, an opportunism-focused transaction cost analysis (OTCA) for PPPs as a governance structure is proposed to supplement the current practice of PPP feasibility analysis. As a part of theory development, a case study of PPP power plants is performed to evaluate the proposed theory and to illustrate how the proposed OTCA can be applied in practice. Policies and administration strategies for power

  13. Analysis and Simulation of Fault Characteristics of Power Switch Failures in Distribution Electronic Power Transformers

    Directory of Open Access Journals (Sweden)

    Dan Wang

    2013-08-01

    Full Text Available This paper presents research on the voltage and current distortion in the input stage, isolation stage and output stage of Distribution Electronic Power transformer (D-EPT after the open-circuit and short-circuit faults of its power switches. In this paper, the operational principles and the control methods for input stage, isolation stage and output stage of D-EPT, which work as a cascaded H-bridge rectifier, DC-DC converter and inverter, respectively, are introduced. Based on conclusions derived from the performance analysis of D-EPT after the faults, this paper comes up with the effects from its topology design and control scheme on the current and voltage distortion. According to the EPT fault characteristics, since the waveforms of relevant components heavily depend on the location of the faulty switch, it is very easy to locate the exact position of the faulty switch. Finally, the fault characteristics peculiar to D-EPT are analyzed, and further discussed with simulation on the Saber platform, as well as a fault location diagnosis algorithm.

  14. 78 FR 4477 - Review of Safety Analysis Reports for Nuclear Power Plants, Introduction

    Science.gov (United States)

    2013-01-22

    ... COMMISSION Review of Safety Analysis Reports for Nuclear Power Plants, Introduction AGENCY: Nuclear... subsection to NUREG-0800, ``Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power..., Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: Integral...

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

    Directory of Open Access Journals (Sweden)

    David G. Behm

    2017-06-01

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

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

    Science.gov (United States)

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

    2017-01-01

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

  17. The future of nuclear power in France: an analysis of the costs of phasing-out

    International Nuclear Information System (INIS)

    Malischek, Raimund; Trüby, Johannes

    2016-01-01

    Nuclear power is an important pillar in electricity generation in France. However, the French nuclear power plant fleet is ageing, and the possibility of reducing the technology's share in power generation or even a complete phase-out has been increasingly discussed. This paper focuses on three inter-related questions: First, what are the costs of phasing-out nuclear power in France? Second, who has to bear these costs, i.e., how much of the costs will be passed on to the rest of the European power system? And third, what effect does the uncertainty regarding future nuclear policy in France have on system costs? Applying a stochastic optimization model for the European electricity system, the analysis showed that additional system costs in France of a nuclear phase-out amount up to 76 billion € 2010 . Additional costs are mostly borne by the French power system. Surprisingly, the analysis found that the costs of uncertainty are rather limited. Based on the results, it can be concluded that a commitment regarding nuclear policy reform is only mildly beneficial in terms of system cost savings. - Highlights: • Analysis of different nuclear policy and phase-out scenarios in France. • Nuclear policy uncertainty in France is treated using stochastic programming. • Costs of a nuclear phase-out in France are significant, amounting up to 76 bill €. • Costs of a phase-out are hardly passed on to the rest of the European power system. • Costs of uncertainty are low, implying little benefit of nuclear policy commitment.

  18. Extreme triple asymmetric (ETAS) epitaxial designs for increased efficiency at high powers in 9xx-nm diode lasers

    Science.gov (United States)

    Kaul, T.; Erbert, G.; Maaßdorf, A.; Martin, D.; Crump, P.

    2018-02-01

    Broad area lasers that are tailored to be most efficient at the highest achievable optical output power are sought by industry to decrease operation costs and improve system performance. Devices using Extreme-Double-ASymmetric (EDAS) epitaxial designs are promising candidates for improved efficiency at high optical output powers due to low series resistance, low optical loss and low carrier leakage. However, EDAS designs leverage ultra-thin p-side waveguides, meaning that the optical mode is shifted into the n-side waveguide, resulting in a low optical confinement in the active region, low gain and hence high threshold current, limiting peak performance. We introduce here explicit design considerations that enable EDAS-based devices to be developed with increased optical confinement in the active layer without changing the p-side layer thicknesses. Specifically, this is realized by introducing a third asymmetric component in the vicinity of the quantum well. We call this approach Extreme-Triple-ASymmetric (ETAS) design. A series of ETAS-based vertical designs were fabricated into broad area lasers that deliver up to 63% power conversion efficiency at 14 W CW optical output power from a 100 μm stripe laser, which corresponds to the operation point of a kW optical output power in a laser bar. The design process, the impact of structural changes on power saturation mechanisms and finally devices with improved performance will be presented.

  19. Expertise about the request of the nuclear power plant Leibstadt for increasing the power to 3600 MW{sub th}; Gutachten zum Gesuch des Kernkraftwerks Leibstadt um Leistungserhoehung auf 3600 MW{sub th}

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-15

    . In the case of design incidents too, all safety-relevant limits and the maximal tolerable dose rates in the environment must be respected. In the context of design incidents, the 'transitory' group also constitutes the limiting case with the higher power. For the complete judgement of the safety of a nuclear power plant it is not sufficient to estimate the effects of a design incident through deterministic methods. The evaluation of the effects of out-of-design accidents needs a probabilistic safety analysis which determines the frequency as well as the consequences of an accident. The results show that KKL represents a very small risk for the environment. In KKL the measures necessary for safe operation and protection of mankind and environment at a thermal power of 3600 MW have already been taken or will be taken shortly. According to its examination, HSK concludes that there are no safety-relevant reasons speaking against an operational license for the increased thermal power. The increase will, however, have to be carried out in 4 steps of 1 year each in order to gain operational experience

  20. A Dynamic Approach to the Analysis of Soft Power in International Relations

    Directory of Open Access Journals (Sweden)

    Chi Zhang

    2013-12-01

    Full Text Available This article discusses soft power in international relations and the soft power of China’s foreign policy in recent years. After presenting a critique of the soft power theory developed by Joseph S. Nye, the paper provides an alternative interpretation of soft power. The author proposes a dynamic analysis of soft power in international relations, and argues that whether a power resource is soft or hard depends on the perceptions and feelings of various actors in specific situations. Due to the varying degrees of acceptance, power can be divided into hard power, soft power and bargaining power. An analysis should look at the soft or hard effectiveness of a power resource from three perspectives–horizontally, vertically and relatively. Recently, the soft power of China’s foreign policy and international behavior has mainly been manifested in multilateralism, economic diplomacy and a good-neighborly policy.