WorldWideScience

Sample records for balance of power

  1. Balance of power

    OpenAIRE

    Lucas, James Raymond

    2012-01-01

    This Paper argues that the efficiency distribution of players in a game determines how aggressively these players interact. We formalize the idea of balance of power: players fight very inefficient players but play softly versus equally (or more) efficient players. This theory of conduct predicts that entry by new firms leads to a less aggressive outcome if it creates a balance of power. A balance of power is created if more players get technologies that are close to the most efficient techno...

  2. Balancing modern Power System with large scale of wind power

    DEFF Research Database (Denmark)

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

    2014-01-01

    Power system operators must ensure robust, secure and reliable power system operation even with a large scale integration of wind power. Electricity generated from the intermittent wind in large propor-tion may impact on the control of power system balance and thus deviations in the power system...... frequency in small or islanded power systems or tie line power flows in interconnected power systems. Therefore, the large scale integration of wind power into the power system strongly concerns the secure and stable grid operation. To ensure the stable power system operation, the evolving power system has...... to be analysed with improved analytical tools and techniques. This paper proposes techniques for the active power balance control in future power systems with the large scale wind power integration, where power balancing model provides the hour-ahead dispatch plan with reduced planning horizon and the real time...

  3. Balance of power theory meets Al Qaeda : dynamics of non-state actor balancing in postinternational politics

    OpenAIRE

    Denk, Aytaç

    2008-01-01

    Ankara : The Department of International Relations, Bilkent University, 2008. Thesis (Master's) -- Bilkent University, 2008. Includes bibliographical references leaves 196-207. The bulk of studies on the balance of power, which constitutes balance of power theory, suggest that only states are involved in balance of power dynamics. This thesis maintains that exclusion of non-state actors (NSAs) from balance of power dynamics constitutes a significant gap in balance of power t...

  4. Dynamic power balance analysis in JET

    International Nuclear Information System (INIS)

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

    2017-01-01

    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. (paper)

  5. Power balance on a multibeam laser

    Science.gov (United States)

    Sampat, S.; Kelly, J. H.; Kosc, T. Z.; Rigatti, A. L.; Kwiatkowski, J.; Donaldson, W. R.; Romanofsky, M. H.; Waxer, L. J.; Dean, R.; Moshier, R.

    2018-02-01

    Inertial confinement fusion (ICF) cryogenic experiments on the 60-beam OMEGA laser have strict requirements for the laser energy delivered on target to be power balanced in order to maximize target-irradiation uniformity. For OMEGA, this quantity (power balance) is inferred from measurements of the time-integrated energy and time-resolved, spatially integrated temporal profile of each of the 60 beams at the output of the laser. The work presented here proposes a general definition of power balance as measured at the laser output and discusses the conditions that are fundamental to achieving laser power balance. Power balance necessitates equal gain across all stages of amplification, equal net losses across each amplifier stage, equal frequency conversion (from 1053 nm to 351 nm) of all 60 beams, and equal beam path lengths (beam timing). Typical OMEGA ICF laser pulse shapes consist of one or more short (100-ps) "pickets" followed by a shaped "drive" pulse of 1 to 2 ns. For these experiments, power balance is assessed for the pickets and the drive independently, with the ultimate goal of achieving root-mean-square (rms) imbalance across all 60 beams of less than 2% rms on both. This work presents a comprehensive summary of laser shot campaigns conducted to significantly improve laser power balance from typical rms values of 4.7% and 5.2%, respectively, to the 3% level for both features along with a discussion of future work required to further reduce the rms power imbalance of the laser system.

  6. Balance of Power

    NARCIS (Netherlands)

    Boone, J.

    2004-01-01

    This paper argues that the efficiency distribution of players in a game determines how aggressively these players interact.We formalize the idea of balance of power: players fight very inefficient players but play softly versus equally (or more) efficient players.This theory of conduct predicts that

  7. Balancing trust and power

    DEFF Research Database (Denmark)

    Broholm-Jørgensen, Marie; Guassora, Ann Dorrit; Reventlow, Susanne

    2017-01-01

    Objective: Little is known about how strategies of retaining patients are acted out by general practitioners (GPs) in the clinical encounter. With this study, we apply Grimens’ (2009) analytical connection between trust and power to explore how trust and power appear in preventive health checks...... of clinical encounters. Results: From the empirical data, we identified three dimensions of respect: respect for the patient’s autonomy, respect for professional authority and respect as a mutual exchange. A balance of respect influenced trust in the relationship between GP and patients and the transfer...... of power in the encounter. The GPs articulated that a balance was needed in preventive health checks in order to establish trust and thus retain the patient in the clinic. One way this balance of respect was carried out was with the use of humour. Conclusions: To retain patients without formal education...

  8. Design of power balance SRAM for DPA-resistance

    Science.gov (United States)

    Keji, Zhou; Pengjun, Wang; Liang, Wen

    2016-04-01

    A power balance static random-access memory (SRAM) for resistance to differential power analysis (DPA) is proposed. In the proposed design, the switch power consumption and short-circuit power consumption are balanced by discharging and pre-charging the key nodes of the output circuit and adding an additional short-circuit current path. Thus, the power consumption is constant in every read cycle. As a result, the DPA-resistant ability of the SRAM is improved. In 65 nm CMOS technology, the power balance SRAM is fully custom designed with a layout area of 5863.6 μm2. The post-simulation results show that the normalized energy deviation (NED) and normalized standard deviation (NSD) are 0.099% and 0.04%, respectively. Compared to existing power balance circuits, the power balance ability of the proposed SRAM has improved 53%. Project supported by the Zhejiang Provincial Natural Science Foundation of China (No. LQ14F040001), the National Natural Science Foundation of China (Nos. 61274132, 61234002), and the K. C. Wong Magna Fund in Ningbo University, China.

  9. Real-time impact of power balancing on power system operation with large scale integration of wind power

    DEFF Research Database (Denmark)

    Basit, Abdul; Hansen, Anca Daniela; Sørensen, Poul Ejnar

    2017-01-01

    Highly wind power integrated power system requires continuous active power regulation to tackle the power imbalances resulting from the wind power forecast errors. The active power balance is maintained in real-time with the automatic generation control and also from the control room, where...... power system model. The power system model takes the hour-ahead regulating power plan from power balancing model and the generation and power exchange capacities for the year 2020 into account. The real-time impact of power balancing in a highly wind power integrated power system is assessed...

  10. Russia-Ukraine balance of military power

    Directory of Open Access Journals (Sweden)

    Jokull Johannesson

    2017-05-01

    Full Text Available The Russia-Ukraine conflict is the most serious test of European security in the 21st century and the forgone conclusion is that Russia can easily prevail in the conflict, but this has not been the case. This article uses balance of military power analysis to report findings on the plausible outcome of a war between Ukraine and Russia. I report findings based on realist theoretical perspectives that indicate Russian victory is unlikely because of relative balance of power where Russia has to face multiple threats diverting its military power while Ukraine can concentrate its military power for a single purpose. The findings suggest implication for policy in Russia, Ukraine, EU and the United States of America.

  11. Russia-Ukraine balance of military power

    OpenAIRE

    Jokull Johannesson

    2017-01-01

    The Russia-Ukraine conflict is the most serious test of European security in the 21st century and the forgone conclusion is that Russia can easily prevail in the conflict, but this has not been the case. This article uses balance of military power analysis to report findings on the plausible outcome of a war between Ukraine and Russia. I report findings based on realist theoretical perspectives that indicate Russian victory is unlikely because of relative balance of power where Russia has to ...

  12. Association of balance, strength, and power measures in young adults.

    Science.gov (United States)

    Muehlbauer, Thomas; Gollhofer, Albert; Granacher, Urs

    2013-03-01

    The purpose of this study was to investigate the relationship between variables of static/dynamic balance, isometric strength, and power. Twenty-seven young healthy adults (mean age: 23 ± 4 years) performed measurements of static (unperturbed)/dynamic (perturbed) balance, isometric strength (i.e., maximal isometric torque [MIT]; rate of torque development [RTD] of the plantar flexor), and power (i.e., countermovement jump [CMJ] height and power). No significant associations were found between variables of static and dynamic balance (r = -0.090 to +0.329, p > 0.05) and between measures of static/dynamic balance and isometric strength (r = +0.041 to +0.387, p > 0.05) and static/dynamic balance and power (r = -0.076 to +0.218, p > 0.05). Significant positive correlations (r) were detected between variables of power and isometric strength ranging from +0.458 to +0.689 (p balance measures and between static/dynamic balance, isometric strength, and power variables implies that these capacities may be independent of each other and may have to be tested and trained complementarily.

  13. Electric power balance sheet 2012

    International Nuclear Information System (INIS)

    2013-01-01

    The mission of RTE, the French electricity Transportation grid, a public service assignment, is to balance the electricity supply and demand in real time. This report presents RTE's technical results for the year 2012: strong seasonal contrast of power consumption, rise of the renewable energies contribution in meeting the electricity demand, slight decay of the nuclear and thermal power generation, decrease of the export balance and change in trades structure, adaptation of RTE's network to the evolutions of the energy system

  14. Hybrid wind power balance control strategy using thermal power, hydro power and flow batteries

    OpenAIRE

    Gelažanskas, Linas; Baranauskas, Audrius; Gamage, Kelum A.A.; Ažubalis, Mindaugas

    2016-01-01

    The increased number of renewable power plants pose threat to power system balance. Their intermittent nature makes it very difficult to predict power output, thus either additional reserve power plants or new storage and control technologies are required. Traditional spinning reserve cannot fully compensate sudden changes in renewable energy power generation. Using new storage technologies such as flow batteries, it is feasible to balance the variations in power and voltage within very short...

  15. Ring power balance observing plasma stability constraints

    International Nuclear Information System (INIS)

    Campbell, R.B.; Logan, B.G.

    1982-01-01

    Ring power balance is performed for an E-ring stabilized tandem mirror reactor, taking into account constraints imposed by plasma stability. The two most important criteria are the stability of the core interchange and hot electron interchange modes. The former determines the ring thickness, the latter determines the minimum hot electron temperature; both quantities are important for power balance. The combination of the hot electron interchange constraint and the fact that the barrier density is low places the operating point on the synchrotron dominated branch of power balance. The reference case considered here requires a reasonable 34 MW of heating power deposited in the rings. We also have examined the sensitivity of the required ring power on uncertainties in the numerical coefficients of the stability constraints. We have found that the heating power is strongly affected

  16. Relationship between strength, power and balance performance in seniors.

    Science.gov (United States)

    Muehlbauer, Thomas; Besemer, Carmen; Wehrle, Anja; Gollhofer, Albert; Granacher, Urs

    2012-01-01

    Deficits in strength, power and balance represent important intrinsic risk factors for falls in seniors. The purpose of this study was to investigate the relationship between variables of lower extremity muscle strength/power and balance, assessed under various task conditions. Twenty-four healthy and physically active older adults (mean age: 70 ± 5 years) were tested for their isometric strength (i.e. maximal isometric force of the leg extensors) and muscle power (i.e. countermovement jump height and power) as well as for their steady-state (i.e. unperturbed standing, 10-meter walk), proactive (i.e. Timed Up & Go test, Functional Reach Test) and reactive (i.e. perturbed standing) balance. Balance tests were conducted under single (i.e. standing or walking alone) and dual task conditions (i.e. standing or walking plus cognitive and motor interference task). Significant positive correlations were found between measures of isometric strength and muscle power of the lower extremities (r values ranged between 0.608 and 0.720, p power and balance (i.e. no significant association in 20 out of 21 cases). Additionally, no significant correlations were found between measures of steady-state, proactive and reactive balance or balance tests performed under single and dual task conditions (all p > 0.05). The predominately nonsignificant correlations between different types of balance imply that balance performance is task specific in healthy and physically active seniors. Further, strength, power and balance as well as balance under single and dual task conditions seem to be independent of each other and may have to be tested and trained complementarily. Copyright © 2012 S. Karger AG, Basel.

  17. 3(omega) Power Balance Procedure on the NIF

    International Nuclear Information System (INIS)

    Glenzer, S; Jones, O; Speck, D R; Munro, D; Lerche, R; Salmon, T; Bliss, E; Gates, A; Boyd, B; Auerbach, J; Williams, W; Saroyan, A; Kalantar, D; MacGowan, B; Zacharias, R; Hayman, C; Sacks, R

    2001-01-01

    This document defines the detailed NIF full system shot procedure to obtain 8% power balance as specified by the SDR002 3.2.1.04. Because the 48 quads of the NIF will be set up over a period of five years, obtaining power balance will naturally be accomplished in two steps. First, as each quad is brought online, the four laser beams within each quad will be tuned by setting the PABTS splitter ratios so that each beam will give the same laser power on target during low energy square pulse shots. During the quad activation period all of the technical tools and procedures will be developed that are needed for attaining full laser power balance. After the initial settings of the 48 PABTS, if no other tuning is done the overall NIF power balance is expected to be about <15%. In the second step, an iteration procedure with approximately 18 full laser system shots will be needed to obtain 8% power balance by tuning out the remaining systematic differences among the quads to an acceptable small difference of 2% rms (at 3ω). This rms difference is smaller than the expected variation of the injection energy or the amplifier gain, and is also of the same order as the laser energy diagnostic accuracy. Therefore, 8% power balance will require a number of precision measurements that will need accurate calibrations combined with a laser performance model that accounts and corrects for variations of the injection energy and the amplifier gain. This document is intended to specify the procedure and the flow-down of requirements from the system design requirement of 8% power balance. It is further intended to help guide the laser shot planning, the laser controls, and the laser performance operations model groups. It should provide input relevant to power balance tuning for the development of an operations model that includes post-shot analysis (as described in NIF-0046491), shot planning (as described in this memo), and pre-shot analysis

  18. Power balance limit in collective ion acceleration

    International Nuclear Information System (INIS)

    Olson, C.L.

    1978-01-01

    The power balance limit to the IREB beam front propagation velocity, as first applied to the problem of collective ion acceleration by Olson in 1973, is investigated in view of recent data of Ecker and Putnam. The beam front velocity β/sub f/c as a function of IREB impedance Z is given, showing the dependence on the power balance limit, the ionization front velocity, and the runaway cutoff. The Olson theory predictions, with no fitted parameters, are shown to be in agreement with the data. Further comparisons of β/sub f/ with respect to the IREB electron energy, the IREB current, and the neutral gas pressure are given. Various forms for the power balance limit are discussed; it is shown that inclusion of the secondary electron power loss term results in an essentially negligible correction to β/sub f/ for typical data parameters. The power balance limit used by Ecker and Putnam is shown to be simply a 3-parameter curve fit, wherein the fitted parameters must exceed their allowed physical values to obtain a reasonable fit for β/sub f/ vs Z. Further, it is shown that this curve fitting leads to serious disagreements with other aspects of the data. It is concluded that the original Olson theory adequately accounts for the data, and that the power balance limit for IREB/gas data is typically not significant except for very small values of Z

  19. French electric power balance sheet 2010

    International Nuclear Information System (INIS)

    Lartigau, Thierry; Riere, Alexia

    2011-01-01

    The mission of RTE, the French electricity Transportation grid, a public service assignment, is to balance the electricity supply and demand in real time. This report presents RTE's technical results for the year 2010: increase of RTE's investments and safety expenses for adapting the grid to the new electricity industry stakes and to meteorological hazards, decrease of power cuts frequency, rise of the French power consumption, strong increase of winter consumption peaks, increase of the French power generation, increase of the positive trade balance. New RTE's infrastructures, electricity quality data, and the evolution of market mechanisms are presented in appendixes

  20. Net energy balance of tokamak fusion power plants

    International Nuclear Information System (INIS)

    Buende, R.

    1981-10-01

    The net energy balance for a tokamak fusion power plant was determined by using a PWR power plant as reference system, replacing the fission-specific components by fusion-specific components and adjusting the non-reactor-specific components to altered conditions. For determining the energy input to the fusion plant a method was developed that combines the advantages of the energetic input-output method with those of process chain analysis. A comparison with PWR, HTR, FBR, and coal-fired power plants is made. As a result the net energy balance of the fusion power plant turns out to be more advantageous than that of an LWR, HTR or coal-fired power plant and nearly in the same range as FBR power plants. (orig.)

  1. CAN THE POWER BALANCE® BRACELET IMPROVE BALANCE, FLEXIBILITY, STRENGTH, AND POWER?

    Directory of Open Access Journals (Sweden)

    John Porcari

    2011-03-01

    Full Text Available Athletes are constantly searching for something that will give them a competitive edge. Performance jewelry is one of the latest products on the market designed to improve athletic performance. The most common claims are that wearing this performance jewelry will improve flexibility, balance, and strength. There is considerable marketing of these products, including testimonial evidence by high profile athletes, in support of the purported benefits. In demonstrations designed to validate the performance enhancing benefits of these products, however, companies typically conduct the testing in the following sequence: The first trial is done without the bracelet on and the second trial is performed with the bracelet on. Invariably, subjects perform better on the second trial. This brings into questions whether the improvement on the second trial is due to 1 a benefit of the bracelet, 2 the fact the subjects were warmed-up (Maud et al., 2006a; 2006b, 3 subjects being habituated to the task (Benson and Friedman, 1996; Wright et al., 2009, or 4 a placebo effect (Beedie and Foad, 2009.One of the most popular performance enhancing bracelets currently on the market is sold by Power Balance® (www.powerbalance.com. The Power Balance® bracelet has two dime-sized holograms; one on either side of the bracelet. The holograms within the Power Balance® bracelet are designed to "resonate with and respond to the natural energy field of the body". This purportedly improves flexibility, balance, and strength. To our knowledge, no randomized, double- blind, placebo trials have ever been conducted evaluating the validity of these claims. Thus, the purpose of this study was to evaluate whether wearing of the Power Balance® bracelet can improve trunk flexibility, balance, strength, and lower body power.Forty-two NCAA Division III athletes (22M: 20.1 ± 1.4 years, 1.82 ± 6.4 m, 82.0 ± 12.6 kg; 20F: 19.5 ± 1.3 years, 1.66 ± 6. 8 m, 63.2 ± 8.1 kg completed four

  2. Effect of the Power Balance® hologram on balance, flexibility, strength and speed-coordination among university students

    Directory of Open Access Journals (Sweden)

    Rafael Merino Marban, Daniel Mayorga Vega, Emilio Fernández Rodríguez, Francisco José Santana Pérez, Oscar Romero Ramos

    2011-01-01

    Full Text Available Based on the body’s energy field, the inventors of Power Balance® have created a hologram that theoretically runs through frequencies that are in our natural environment. Its creators say that people may experience improve balance, strength, flexibility, endurance, concentration, coordination and recovery time, among others. The purpose of this research is to evaluate the effect of Power Balance® hologram on balance, flexibility, strength and speed-coordination in university students. A sample of 105 young volunteers’ physical education students (age 20.91 ± 3.36 years, mass 69.69 ± 11.35 kg, height 171.70 ± 8.07 cm was used. A between-group experimental design with double-blind control group was used to evaluate the possible effects of the Power Balance ® on the dynamic balance, flexibility, abdominal strength, endurance and speed-coordination measured with the Dynamic Balance Test, Sit and Reach, Sit-ups in 30 seconds and Race 10 x 5 m, respectively. A t of Student for independent and dependent samples was used to assess the potential effects between-group and intra-group, respectively. Power Balance®’s hologram produces no significant effects on the balance, flexibility, strength and speed-coordination among university students

  3. Power distribution in complex environmental negotiations: Does balance matter?

    Science.gov (United States)

    Burkardt, N.; Lamb, B.L.; Taylor, J.G.

    1997-01-01

    We studied six interagency negotiations covering Federal Energy Regulatory Commission (FERC) hydroelectric power licenses. Negotiations occurred between state and federal resource agencies and developers over project operations and natural resource mitigation. We postulated that a balance of power among parties was necessary for successful negotiations. We found a complex relationship between balanced power and success and conclude that a balance of power was associated with success in these negotiations. Power played a dynamic role in the bargaining and illuminates important considerations for regulatory design.

  4. Cost reduction potentials in the German market for balancing power

    International Nuclear Information System (INIS)

    Flinkerbusch, Kai; Heuterkes, Michael

    2010-01-01

    This article examines potential cost reductions in the market for balancing power by pooling all four German control areas. In a united control area both the procurement and the production of balancing power may be more efficient than in four separated control areas. Our data contain bids on energy procurement as well as balancing power flows in the period from December 2007 to November 2008. A reference scenario simulates the market results for secondary and tertiary balancing power. Subsequently, we simulate a united control area. We show that in the period under review the total costs of balancing power are reduced by 17%. (author)

  5. Balancing U.S. Power in the 21st Century

    National Research Council Canada - National Science Library

    Caves, John

    2000-01-01

    The (neo)realist balance of power model stipulates that states seek to provide for their own security in an essentially anarchic international system by balancing the power of other states that pose...

  6. Harmonic and power balance tools for tapping-mode atomic force microscope

    International Nuclear Information System (INIS)

    Sebastian, A.; Salapaka, M. V.; Chen, D. J.; Cleveland, J. P.

    2001-01-01

    The atomic force microscope (AFM) is a powerful tool for investigating surfaces at atomic scales. Harmonic balance and power balance techniques are introduced to analyze the tapping-mode dynamics of the atomic force microscope. The harmonic balance perspective explains observations hitherto unexplained in the AFM literature. A nonconservative model for the cantilever - sample interaction is developed. The energy dissipation in the sample is studied and the resulting power balance equations combined with the harmonic balance equations are used to estimate the model parameters. Experimental results confirm that the harmonic and power balance tools can be used effectively to predict the behavior of the tapping cantilever. [copyright] 2001 American Institute of Physics

  7. Distributed Control of the Power Supply-Demand Balance

    NARCIS (Netherlands)

    Larsen, Gunn K. H.; van Foreest, Nicky D.; Scherpen, Jacquelien M. A.

    This paper aims to achieve a balance of power in a group of prosumers, based on a price mechanism, i.e., to steer the difference between the total production and consumption of power to zero. We first set the information network topology such that the prosumers exchange price (power) information

  8. T55 power turbine rotor multiplane-multispeed balancing study

    Science.gov (United States)

    Martin, M. R.

    1982-01-01

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

  9. Effect of the Power Balance® band on static balance, hamstring flexibility, and arm strength in adults.

    Science.gov (United States)

    Verdan, Princess J R; Marzilli, Thomas S; Barna, Geanina I; Roquemore, Anntionette N; Fenter, Brad A; Blujus, Brittany; Gosselin, Kevin P

    2012-08-01

    The purpose of this study was to determine the effect of Power Balance® bands on strength, flexibility, and balance. Strength and flexibility were measured using the MicroFit system. Strength was measured via a bicep curl and flexibility via the sit-and-reach method. Balance was measured by the BIODEX System SD. There were 4 different conditions for the balance test: eyes open on a firm surface (EOFS), eyes closed on a firm surface (ECFS), eyes open on a foam surface (EOFoS), and eyes closed on a foam surface (ECFoS). There were 24 subjects in the study (10 men and 14 women). A counterbalance, double-blind, placebo, controlled within-subject design was used. Each of the subjects participated in 3 treatment sessions, consisting of Power Balance®, placebo band, and no band. An alpha level of p ≤ 0.05 was set a priori. There were no significant differences in strength, flexibility, or balance with regard to the treatments used. There was a significant difference between the conditions in the balance test (p = 0.000): EOFS (0.51), ECFS (0.68), EOFoS (0.99), and ECFoS (2.18); however, these were independent of the treatment conditions. The results indicate that the Power Balance® bands did not have an effect on strength, flexibility, or balance.

  10. Modeling real-time balancing power demands in wind power systems using stochastic differential equations

    International Nuclear Information System (INIS)

    Olsson, Magnus; Perninge, Magnus; Soeder, Lennart

    2010-01-01

    The inclusion of wind power into power systems has a significant impact on the demand for real-time balancing power due to the stochastic nature of wind power production. The overall aim of this paper is to present probabilistic models of the impact of large-scale integration of wind power on the continuous demand in MW for real-time balancing power. This is important not only for system operators, but also for producers and consumers since they in most systems through various market solutions provide balancing power. Since there can occur situations where the wind power variations cancel out other types of deviations in the system, models on an hourly basis are not sufficient. Therefore the developed model is in continuous time and is based on stochastic differential equations (SDE). The model can be used within an analytical framework or in Monte Carlo simulations. (author)

  11. A power balance model for handcycling

    NARCIS (Netherlands)

    Groen, Wim G.; van der Woude, Lucas H. V.; De Koning, Jos J.

    2010-01-01

    Purpose. To demonstrate the applicability of the power balance model to elite handcycling and to obtain values for gross efficiency (GE). Methods. Four members of the Dutch Paralympic team performed trials on a 250-m indoor track. Velocity (v) and power output (PO) were measured in conjunction with

  12. Power balancing of multibeam laser fusion lasers

    International Nuclear Information System (INIS)

    Seka, W.; Morse, S.; Letzring, S.; Kremens, R.; Kessler, T.J.; Jaanimagi, P.; Keck, R.; Verdon, C.; Brown, D.

    1989-01-01

    The success of laser fusion depends to a good degree on the ability to compress the target to very high densities of ≥1000 times liquid DT. To achieve such compressions require that the irradiation nonuniformity must not exceed ∼1% rms over the whole time of the compression, particularly during the early phases of irradiation. The stringent requirements for the irradiation uniformity for laser fusion have been known for quite some time but until recently the energy balance was mistakenly equated to power balance. The authors describe their effort on energy balance and irradiation patterns on the target. They significantly improved the laser performance with respect to overall intensity distributions on target including the implementation of distributed (random) phase plates in each high power beam. However, the slightly varying performance of the third harmonic conversion crystals in the twenty-four beams of their laser system was generally compensated for by appropriately adjusted 1.054μm input laser energy. Computational analysis of the results of the recent high density campaign are shown

  13. Balancing computation and communication power in power constrained clusters

    Science.gov (United States)

    Piga, Leonardo; Paul, Indrani; Huang, Wei

    2018-05-29

    Systems, apparatuses, and methods for balancing computation and communication power in power constrained environments. A data processing cluster with a plurality of compute nodes may perform parallel processing of a workload in a power constrained environment. Nodes that finish tasks early may be power-gated based on one or more conditions. In some scenarios, a node may predict a wait duration and go into a reduced power consumption state if the wait duration is predicted to be greater than a threshold. The power saved by power-gating one or more nodes may be reassigned for use by other nodes. A cluster agent may be configured to reassign the unused power to the active nodes to expedite workload processing.

  14. Power loss measurement of implantable wireless power transfer components using a Peltier device balance calorimeter

    International Nuclear Information System (INIS)

    Leung, Ho Yan; Budgett, David M; Taberner, Andrew; Hu, Patrick

    2014-01-01

    Determining heat losses in power transfer components operating at high frequencies for implantable inductive power transfer systems is important for assessing whether the heat dissipated by the component is acceptable for implantation and medical use. However, this is a challenge at high frequencies and voltages due to limitations in electronic instrumentation. Calorimetric methods of power measurement are immune to the effects of high frequencies and voltages; hence, the measurement is independent of the electrical characteristics of the system. Calorimeters have been widely used to measure the losses of high power electrical components (>50 W), however it is more difficult to perform on low power components. This paper presents a novel power measurement method for components dissipating anywhere between 0.2 W and 1 W of power based on a heat balance calorimeter that uses a Peltier device as a balance sensor. The proposed balance calorimeter has a single test accuracy of ±0.042 W. The experimental results revealed that there was up to 35% difference between the power measurements obtained with electrical methods and the proposed calorimeter. (paper)

  15. Power and energy balances. Forecast 2008

    International Nuclear Information System (INIS)

    2005-01-01

    Both the energy and power balance in 2008 is slightly better than the former Nordel estimate for 2007. This is due to additional investments in new generation capacity, new interconnections of total 1 000 MW to outside Nordel and reduced demand forecast in Sweden. The Nordic electricity system is able to meet the estimated consumption and the corresponding typical power demand pattern in average conditions. In long term the market is expected to maintain a reasonable balance between supply, imports and demand. Lower precipitation or colder temperature result in higher market prices that give incentives for increased imports, demand response and investments. This is expected to maintain the balance between supply and demand in the short and long term even in extreme situations. Allocation between imports and demand response in reality depends on the prevailing market prices and available generation resources outside Nordel. The interconnection capacities are expected to enable import volumes that can meet the increased peak demand. Some Nordic areas can be exposed to a risk for rationing or other measures because of extremely low precipitation. Nordic transmission capacities may prevent full utilization of Nordic thermal power in certain areas. The planned reinforcements in the 'five prioritised cross-sections' will improve the situation. The power balance and the internal bottlenecks in the continental Europe can have an effect on the import possibilities to the Nordic countries. The annual energy consumption in the Nordic market is estimated to grow by 20 TWh by year 2008 (1.2%la) from 395 TWh in 2004 (temperature corrected). In the three year period investments in power generation is expected to increase the available generation capacity and capability by 1500 MW and 10 TWhla in average conditions. Iceland is not included in the figures. The annual energy consumption in Iceland is estimated to grow by about 6.8 TWh by year 2008 (15 %la) due to two new aluminium

  16. Challenging the balance of power: patient empowerment.

    Science.gov (United States)

    Hewitt-Taylor, Jaquelina

    Empowering patients is a central element of nursing care, according to the RCN (2003). This article discusses the reality of changing the balance of power in health care, awareness of types of knowledge and the ways in which power may consciously or subconsciously be used. It also includes awareness of the financial and political aspects of health care and how these affect patient choice.

  17. Learning Responsibility and Balance of Power

    Science.gov (United States)

    Çam, Sefika Sümeyye; Ünal Oruç, Eylem

    2014-01-01

    This qualitative study aims to determine teacher perspectives on learning responsibility and balance of power. The research design is case study which was conducted on four primary school teachers. The data were collected with semi-structured interviews and the data obtained were analyzed with categorical analysis, a type of content analysis. The…

  18. Separation of Powers: Checks and Balances.

    Science.gov (United States)

    Taylor, Bonnie

    1988-01-01

    This article offers a class activity on separation of powers and checks and balances within the U.S. government. Based on Franklin Delano Roosevelt's attempt to push through legislation for the New Deal of the 1930s by "packing" the U.S. Supreme Court, the activity includes worksheets and teaching suggestions. (JDH)

  19. Well-functioning balancing markets. A prerequisite for wind power integration

    International Nuclear Information System (INIS)

    Vandezande, Leen; Meeus, Leonardo; Belmans, Ronnie; Saguan, Marcelo; Glachant, Jean-Michel

    2010-01-01

    This article focuses on the design of balancing markets in Europe taking into account an increasing wind power penetration. In several European countries, wind generation is so far not burdened with full balancing responsibility. However, the more wind power penetration, the less bearable for the system not to allocate balancing costs to the responsible parties. Given the variability and limited predictability of wind generation, full balancing exposure is however only feasible conditionally to well-functioning balancing markets. On that account, recommendations ensuring an optimal balancing market design are formulated and their impact on wind generation is assessed. Taking market-based or cost-reflective imbalance prices as the main objective, it is advised that: (1) the imbalance settlement should not contain penalties or power exchange prices, (2) capacity payments should be allocated to imbalanced BRPs via an additive component in the imbalance price and (3) a cap should be imposed on the amount of reserves. Efficient implementation of the proposed market design may require balancing markets being integrated across borders. (author)

  20. Power and energy balances, today and three years ahead

    International Nuclear Information System (INIS)

    Borg, Trygve; Maula, H.; Pedersen, Jens; Soendergren, C.; Waegelund, G.; Granlund, K.

    2003-06-01

    Energy scenario 2006: In normal conditions the Nordel system is balancing well. It is expected that the Nordel system will cope with a single dry year situation. if a year with extreme low hydropower production or a combination of two dry years in succession occurs, the result may be a very serious balance deficit. For part of the Nordel system it is possible that market cannot solve the problem and the situation will demand various forms of rationing or other measures. Power balance winter peak demand 2006/07: During a normal winter, peak demand will be handled without difficulties. If a ten years winter occurs the power balance is expected to come under strain and the Nordic power system is dependent on import from Europe via strong interconnections. The forecast shows that there probably is enough production capacity and import possibilities from countries outside Nordel. (BA)

  1. The relationships of eccentric strength and power with dynamic balance in male footballers.

    Science.gov (United States)

    Booysen, Marc Jon; Gradidge, Philippe Jean-Luc; Watson, Estelle

    2015-01-01

    Unilateral balance is critical to kicking accuracy in football. In order to design interventions to improve dynamic balance, knowledge of the relationships between dynamic balance and specific neuromuscular factors such as eccentric strength and power is essential. Therefore, the aim was to determine the relationships of eccentric strength and power with dynamic balance in male footballers. The Y-balance test, eccentric isokinetic strength testing (knee extensors and flexors) and the countermovement jump were assessed in fifty male footballers (university (n = 27, mean age = 20.7 ± 1.84 years) and professional (n = 23, mean age = 23.0 ± 3.08 years). Spearman Rank Order correlations were used to determine the relationships of eccentric strength and power with dynamic balance. Multiple linear regression, adjusting for age, mass, stature, playing experience and competitive level was performed on significant relationships. Normalised reach score in the Y-balance test using the non-dominant leg for stance correlated with (1) eccentric strength of the non-dominant leg knee extensors in the university group (r = 0.50, P = 0.008) and (2) countermovement jump height in the university (r = 0.40, P = 0.04) and professional (r = 0.56, P = 0.006) football groups, respectively. No relationships were observed between eccentric strength (knee flexors) and normalised reach scores. Despite the addition of potential confounders, the relationship of power and dynamic balance was significant (r = 0.52, P power correlates moderately with dynamic balance on the non-dominant leg in male footballers.

  2. French electric power balance sheet 2009

    International Nuclear Information System (INIS)

    Lartigau, Thierry; Riere, Alexia

    2010-01-01

    The mission of RTE, the French electricity Transportation grid, a public service assignment, is to balance the electricity supply and demand in real time. This report presents RTE's technical results for the year 2009: key figures of the French electricity consumption, lowering of the French power generation, decrease of trade balance at borders but still positive, continuation of RTE's investments for the improvement of the grid performance. New RTE's infrastructures, electricity quality data, and the evolution of market mechanisms are presented in appendixes

  3. Accuracy requirements on operational measurements in nuclear power plants with regard to balance methodology

    International Nuclear Information System (INIS)

    Holecek, C.

    1986-01-01

    Accurate in-service measurement is necessary for power balancing of nuclear power plants, i.e., the determination of fuel consumption, electric power generation, heat delivery and the degree of fuel power utilization. The only possible method of determining the input of total consumed energy from the fuel is the balance of the primary coolant circuit. This is because for the purposes of power balancing it is not possible to measure the amount of power generated from nuclear fuel. Relations are presented for the calculation of basic indices of the power balance. It is stated that for the purposes of power balancing and analyses the precision of measuring instrument at the input and output of balancing circuits is of primary importance, followed by the precision of measuring instruments inside balancing circuits and meters of auxiliary parameters. (Z.M.). 7 refs., 1 tab

  4. Ultrasound power measurements of HITU transducer with a more stable radiation force balance

    International Nuclear Information System (INIS)

    Karaboece, B; Sadiko'lu, E; Bilgic, E

    2011-01-01

    A new radiation force balance (RFB) system was established at Turkish National Metrology Institute (UME) Ultrasonics Laboratory for High intensity therapeutic ultrasound (HITU) power measurements. The new system is highly stable at high power levels up to 500 Watts. The measurement system consists of a Plexiglas cylindrical balance arm, target mounting scale disks, conical reflecting and absorbing targets, adjustment nuts, and a hanging wire. Both of the two sides of balance were mounted similar size and weight targets. The equilibrium of the balance arm can be adjusted with nuts on screws located at both sides of the balance arm. Transducer was mounted to bottom of water tank. Absorbers in the bottom and the near walls of the tank were used for reflecting target case. Ultrasound power was applied to one scale of the balance where the reflecting/absorbing target was mounted and corresponding force was measured on the other scale of balance where was connected to a balance with a thin wire while the thin rest standing on a support. Ultrasound power of two HITU transducers at frequencies 0.93 MHz, 1.1 MHz and 3.3 MHz were measured with conventional and new system, the values were compared and uncertainty components were assessed in this paper.

  5. Ultrasound power measurements of HITU transducer with a more stable radiation force balance

    Energy Technology Data Exchange (ETDEWEB)

    Karaboece, B; Sadiko' lu, E; Bilgic, E, E-mail: baki.karaboce@ume.tubitak.gov.t [Tuebitak Ulusal Metroloji Enstituesue (UME), P.K. 54 41470 Gebze-Kocaeli (Turkey)

    2011-02-01

    A new radiation force balance (RFB) system was established at Turkish National Metrology Institute (UME) Ultrasonics Laboratory for High intensity therapeutic ultrasound (HITU) power measurements. The new system is highly stable at high power levels up to 500 Watts. The measurement system consists of a Plexiglas cylindrical balance arm, target mounting scale disks, conical reflecting and absorbing targets, adjustment nuts, and a hanging wire. Both of the two sides of balance were mounted similar size and weight targets. The equilibrium of the balance arm can be adjusted with nuts on screws located at both sides of the balance arm. Transducer was mounted to bottom of water tank. Absorbers in the bottom and the near walls of the tank were used for reflecting target case. Ultrasound power was applied to one scale of the balance where the reflecting/absorbing target was mounted and corresponding force was measured on the other scale of balance where was connected to a balance with a thin wire while the thin rest standing on a support. Ultrasound power of two HITU transducers at frequencies 0.93 MHz, 1.1 MHz and 3.3 MHz were measured with conventional and new system, the values were compared and uncertainty components were assessed in this paper.

  6. Power balance and loss mechanism analysis in RF transmit coil arrays.

    Science.gov (United States)

    Kuehne, Andre; Goluch, Sigrun; Waxmann, Patrick; Seifert, Frank; Ittermann, Bernd; Moser, Ewald; Laistler, Elmar

    2015-10-01

    To establish a framework for transmit array power balance calculations based on power correlation matrices to accurately quantify the loss contributions from different mechanisms such as coupling, lumped components, and radiation. Starting from Poynting's theorem, power correlation matrices are derived for all terms in the power balance, which is formulated as a matrix equation. Finite-difference time-domain simulations of two 7 T eight-channel head array coils at 297.2 MHz are used to verify the theoretical considerations and demonstrate their application. Care is taken to accurately incorporate all loss mechanisms. The power balance for static B1 phase shims as well as two-dimensional spatially selective transmit SENSE pulses is shown. The simulated power balance shows an excellent agreement with theory, with a maximum power imbalance of less than 0.11%. Power loss contributions from the different loss mechanisms vary significantly between the investigated setups, and depending on the excitation mode imposed on the coil. The presented approach enables a straightforward loss evaluation for an arbitrary excitation of transmit coil arrays. Worst-case power imbalance and losses are calculated in a straightforward manner. This allows for deeper insight into transmit array loss mechanisms, incorporation of radiated power components in specific absorption rate calculations and verification of electromagnetic simulations. © 2014 Wiley Periodicals, Inc.

  7. Gender-specific influences of balance, speed, and power on agility performance.

    Science.gov (United States)

    Sekulic, Damir; Spasic, Miodrag; Mirkov, Dragan; Cavar, Mile; Sattler, Tine

    2013-03-01

    The quick change of direction (i.e., agility) is an important athletic ability in numerous sports. Because of the diverse and therefore hardly predictable manifestations of agility in sports, studies noted that the improvement in speed, power, and balance should result in an improvement of agility. However, there is evident lack of data regarding the influence of potential predictors on different agility manifestations. The aim of this study was to determine the gender-specific influence of speed, power, and balance on different agility tests. A total of 32 college-aged male athletes and 31 college-aged female athletes (age 20.02 ± 1.89 years) participated in this study. The subjects were mostly involved in team sports (soccer, team handball, basketball, and volleyball; 80% of men, and 75% of women), martial arts, gymnastics, and dance. Anthropometric variables consisted of body height, body weight, and the body mass index. Five agility tests were used: a t-test (T-TEST), zig-zag test, 20-yard shuttle test, agility test with a 180-degree turn, and forward-backward running agility test (FWDBWD). Other tests included 1 jumping ability power test (squat jump, SQJ), 2 balance tests to determine the overall stability index and an overall limit of stability score (both measured by Biodex Balance System), and 2 running speed tests using a straight sprint for 10 and 20 m (S10 and S20, respectively). A reliability analysis showed that all the agility tests were reliable. Multiple regression and correlation analysis found speed and power (among women), and balance (among men), as most significant predictors of agility. The highest Pearson's correlation in both genders is found between the results of the FWDBWD and S10M tests (0.77 and 0.81 for men and women, respectively; p Power, measured using the SQJ, is significantly (p balance measures were significantly related to the agility performance for men but not for women. In addition to demonstrating a known relationship

  8. Test-bed Assessment of Communication Technologies for a Power-Balancing Controller

    DEFF Research Database (Denmark)

    Findrik, Mislav; Pedersen, Rasmus; Hasenleithner, Eduard

    2016-01-01

    and control. In this paper, we present a Smart Grid test-bed that integrates various communication technologies and deploys a power balancing controller for LV grids. Control performance of the introduced power balancing controller is subsequently investigated and its robustness to communication network cross......Due to growing need for sustainable energy, increasing number of different renewable energy resources are being connected into distribution grids. In order to efficiently manage a decentralized power generation units, the smart grid will rely on communication networks for information exchange...

  9. Reduced storage and balancing needs in a fully renewable European power system with excess wind and solar power generation

    DEFF Research Database (Denmark)

    Heide, Dominik; Greiner, Martin; von Bremen, Lüder

    The storage and balancing needs of a simplified European power system, which is based on wind and solar power generation only, are derived from an extensive weather-driven modeling of hourly power mismatches between generation and load. The storage energy capacity, the annual balancing energy...... and the balancing power are found to depend significantly on the mixing ratio between wind and solar power generation. They decrease strongly with the overall excess generation. At 50% excess generation the required long-term storage energy capacity and annual balancing energy amount to 1% of the annual consumption....... The required balancing power turns out to be 25% of the average hourly load. These numbers are in agreement with current hydro storage lakes in Scandinavia and the Alps, as well as with potential hydrogen storage in mostly North-German salt caverns....

  10. Reduced storage and balancing needs in a fully renewable European power system with excess wind and solar power generation

    DEFF Research Database (Denmark)

    Heide, Dominik; Greiner, Martin; von Bremen, Lüder

    2011-01-01

    The storage and balancing needs of a simplified European power system, which is based on wind and solar power generation only, are derived from an extensive weather-driven modeling of hourly power mismatches between generation and load. The storage energy capacity, the annual balancing energy...... and the balancing power are found to depend significantly on the mixing ratio between wind and solar power generation. They decrease strongly with the overall excess generation. At 50% excess generation the required long-term storage energy capacity and annual balancing energy amount to 1% of the annual consumption....... The required balancing power turns out to be 25% of the average hourly load. These numbers are in agreement with current hydro storage lakes in Scandinavia and the Alps, as well as with potential hydrogen storage in mostly North-German salt caverns....

  11. Analysis of Balancing Requirements in Future Sustainable and Reliable Power Systems

    International Nuclear Information System (INIS)

    Frunt, J.

    2011-01-01

    This thesis elaborates on the rules for power balancing, provides a method for quantifying balancing requirements and examines the effect of future changes on balancing. Chapter 2 elaborates on system balancing and the different actors and entities in the electricity delivery system. The necessity and implementation of power balancing are explained. Also different subsequent markets (i.e., day-ahead markets, intraday markets and imbalance settlement systems) and options to trade electricity are discussed. As the research focusses mainly on the Netherlands, properties of the Dutch imbalance settlement system are analyzed. Based on this framework an in-depth analysis of imbalances and calls for balancing capacity with the corresponding prices is given. This shows the incentives to minimize the amount of imbalance in the system and to participate in the imbalance settlement system. Chapter 3 elaborates on the level of aggregation that the entities, involved in the imbalance settlement system, in electricity markets can have. Based on current market rules, incentives to either grow or shrink and by aggregating more or less entities are discussed. The level of aggregation will directly influence the functioning of the imbalance settlement system. It is shown that larger aggregations benefit more from the canceling out of imbalances. The imbalances of the Netherlands and Belgium have been aggregated to illustrate the possible benefits of aggregating multiple national imbalance settlement systems. The increased penetration of renewable generation strongly influences the planning and operation of the power system. As many renewable energy generators have a fluctuating power output, several methods are discussed in chapter 4 that can be used to classify and quantify the balancing requirements to counteract these fluctuations. Chapter 4 discusses the multiple existing classes of balancing capacity and the corresponding methods to quantify their needs. Due to the

  12. Analysis of Balancing Requirements in Future Sustainable and Reliable Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Frunt, J.

    2011-06-01

    This thesis elaborates on the rules for power balancing, provides a method for quantifying balancing requirements and examines the effect of future changes on balancing. Chapter 2 elaborates on system balancing and the different actors and entities in the electricity delivery system. The necessity and implementation of power balancing are explained. Also different subsequent markets (i.e., day-ahead markets, intraday markets and imbalance settlement systems) and options to trade electricity are discussed. As the research focusses mainly on the Netherlands, properties of the Dutch imbalance settlement system are analyzed. Based on this framework an in-depth analysis of imbalances and calls for balancing capacity with the corresponding prices is given. This shows the incentives to minimize the amount of imbalance in the system and to participate in the imbalance settlement system. Chapter 3 elaborates on the level of aggregation that the entities, involved in the imbalance settlement system, in electricity markets can have. Based on current market rules, incentives to either grow or shrink and by aggregating more or less entities are discussed. The level of aggregation will directly influence the functioning of the imbalance settlement system. It is shown that larger aggregations benefit more from the canceling out of imbalances. The imbalances of the Netherlands and Belgium have been aggregated to illustrate the possible benefits of aggregating multiple national imbalance settlement systems. The increased penetration of renewable generation strongly influences the planning and operation of the power system. As many renewable energy generators have a fluctuating power output, several methods are discussed in chapter 4 that can be used to classify and quantify the balancing requirements to counteract these fluctuations. Chapter 4 discusses the multiple existing classes of balancing capacity and the corresponding methods to quantify their needs. Due to the

  13. Maintaining the power balance in an "empty network"

    NARCIS (Netherlands)

    Reza, M.; Dominguez, A.O.; Schavemaker, P.H.; Kling, W.L.

    2006-01-01

    This paper presents the concept of an empty network and shows how the power balance can be maintained in such a system. In this study, an empty network is defined as a power system in which no rotating mass is present; all generators are grid-connected via power electronic interfaces. One generator

  14. Associations Between Balance and Muscle Strength, Power Performance in Male Youth Athletes of Different Maturity Status.

    Science.gov (United States)

    Hammami, Raouf; Chaouachi, Anis; Makhlouf, Issam; Granacher, Urs; Behm, David G

    2016-11-01

    Balance, strength and power relationships may contain important information at various maturational stages to determine training priorities. The objective was to examine maturity-specific relationships of static/dynamic balance with strength and power measures in young male athletes. Soccer players (N = 130) aged 10-16 were assessed with the Stork and Y balance (YBT) tests. Strength/power measures included back extensor muscle strength, standing long jump (SLJ), countermovement jump (CMJ), and 3-hop jump tests. Associations between balance with strength/power variables were calculated according to peak-height-velocity (PHV). There were significant medium-large sized correlations between all balance measures with back extensor strength (r = .486-.791) and large associations with power (r = .511-.827). These correlation coefficients were significantly different between pre-PHV and circa PHV as well as pre-PHV and post-PHV with larger associations in the more mature groups. Irrespective of maturity-status, SLJ was the best strength/power predictor with the highest proportion of variance (12-47%) for balance (i.e., Stork eyes opened) and the YBT was the best balance predictor with the highest proportion of variance (43-78%) for all strength/power variables. The associations between balance and muscle strength/power measures in youth athletes that increase with maturity may imply transfer effects from balance to strength/power training and vice versa in youth athletes.

  15. Power Balance AODV Routing Algorithm of WSN in Precision Agriculture Environment Monitoring

    Directory of Open Access Journals (Sweden)

    Xiaoqin Qin

    2013-11-01

    Full Text Available As one of important technologies of IOT (Internet of Things, WSN (Wireless Sensor Networks has been widely used in precision agriculture environment monitoring. WSN is a kind of energy-constrained network, but power balance is not taken into account in traditional routing protocols. A novel routing algorithm, named Power Balance Ad hoc On-Demand Distance Vector (PB-AODV, is proposed on cross-layer design. In the route discovery process of PB-AODV, routing path is established by the Received Signal Strength Indication (RSSI value. The optimal transmitting power, which is computed according to RSSI value, power threshold and node’s surplus energy, is encapsulated into Route Reply Packet. Hence, the sender node can adjust its transmission power to save energy according to the Route Reply Packet. Simulation results show that the proposed algorithm is effective for load balancing, and increases the WSN’s lifetime 14.3% consequently.

  16. Synthetic methods for beam to beam power balancing capability of large laser facilities

    International Nuclear Information System (INIS)

    Chen Guangyu; Zhang Xiaomin; Zhao Runchang; Zheng Wanguo; Yang Xiaoyu; You Yong; Wang Chengcheng; Shao Yunfei

    2011-01-01

    To account for output power balancing capability of large laser facilities, a synthetic method with beam to beam root-mean-square is presented. Firstly, a conversion process for the facilities from original data of beam powers to regular data is given. The regular data contribute to the normal distribution approximately, and then a corresponding simple method of root-mean-square for beam to beam power balancing capability is given.Secondly, based on theory of total control charts and cause-selecting control charts, control charts with root-mean-square are established which show short-term variety of power balancing capability of the facilities. Mean rate of failure occurrence is also defined and used to describe long-term trend of global balancing capabilities of the facilities. Finally, advantages of the intuitive and efficient diagnosis for synthetic methods are illustrated by analysis of experimental data. (authors)

  17. Modeling and simulating an electrical grid subsystem for power balance analysis

    DEFF Research Database (Denmark)

    Totu, Luminita Cristiana; Leth, John-Josef; Wisniewski, Rafal

    2012-01-01

    We present an approach for power balance analysis in Smart Grids where the physical behavior of different electrical devices is modeled at unit level, and the collective load and generation curves can later be obtained by aggregation. In this way, new behaviors, flexibilities and intelligent...... strategies for power consumption and generation can be easily introduced at the user-level and the system-level impact analyzed on the aggregated profiles. The future aim is to investigate bottom-up balancing strategies, where units with a flexible energy band can react independently to power balance signals...

  18. T700 power turbine rotor multiplane/multispeed balancing demonstration

    Science.gov (United States)

    Burgess, G.; Rio, R.

    1979-01-01

    Research was conducted to demonstrate the ability of influence coefficient based multispeed balancing to control rotor vibration through bending criticals. Rotor dynamic analyses were conducted of the General Electric T700 power turbine rotor. The information was used to generate expected rotor behavior for optimal considerations in designing a balance rig and a balance technique. The rotor was successfully balanced 9500 rpm. Uncontrollable coupling behavior prevented observations through the 16,000 rpm service speed. The balance technique is practical and with additional refinement it can meet production standards.

  19. French electric power balance sheet 2006

    International Nuclear Information System (INIS)

    Derdevet, Michel; Usatorre, Karine de

    2007-01-01

    The mission of RTE, the French electricity Transportation grid, a public service assignment, is to balance the electricity supply and demand in real time. This report presents RTE's technical results for the year 2006: key figures of the electricity balance sheet, RTE's public utility commitments, efficient market mechanisms and free flow of trades, lessons learnt from the power breakdown of November 4, 2006. The evolution of RTE's infrastructures and production means, the contract with Gaz de France for the improvement of Brittany's security of supply, and the results of RTE's 2006 satisfaction survey are presented in appendixes

  20. Net energy balance of tokamak fusion power plants

    International Nuclear Information System (INIS)

    Buende, R.

    1983-01-01

    The net energy balance for a tokamak fusion power plant of present day design is determined by using a PWR power plant as reference system, replacing the fission-specific components by fusion-specific components and adjusting the non-reactor-specific components to altered conditions. For determining the energy input to the fusion plant a method was developed that combines the advantages of the energetic input-output method with those of process chain analysis. A comparison with PWR, HTR, FBR, and coal-fired power plants is made. As a result the energy expenditures of the fusion power plant turn out to be lower than that of an LWR, HTR, or coal-fired power plant of equal net electric power output and nearly in the same range as FBR power plants. (orig.)

  1. Social assessment of wind power. Part 3: Employment and balance of payments

    International Nuclear Information System (INIS)

    Munksgaard, J.; Rahbaek Pedersen, J.; Jensen, T.

    1995-12-01

    The main object of this report is to investigate the consequences of a wind power development of the Danish electricity system on employment and the balance of payments. The development is carried out as an investment in 1,000 MW wind power compared to a 450 MW coal-based central power plant. The wind power development is consistent with 'Energy 2000 - A Plan of Action for Sustainable Development' from the Danish Ministry of Energy which states that a total capacity of 1,500 MW should be reached by 2005. The effects on the employment and the balance of payments will be quantified as employed per year and million DKK per year respectively. This is due to the opinion that these effects should not have decisive influence on the assessment of long term energy and environmental projects. Based on the assumptions on the cost-efficiency of wind power the capacity of 1,000 MW wind power, supplied by 220 MW backup capacity from natural gas-fired turbines, is equivalent to a 420 MW central power plant base on coal. This forms the basis of two scenarios: a wind power scenario and a coal power scenario. The overall result in this report is that the effects on employment and the balance of payments do not differ very much. Therefore one cannot recommend nor reject wind power in the Danish electricity system compared to a coal-based central power plant. (EG) 13 refs

  2. Measures of static postural control moderate the association of strength and power with functional dynamic balance.

    Science.gov (United States)

    Forte, Roberta; Boreham, Colin A G; De Vito, Giuseppe; Ditroilo, Massimiliano; Pesce, Caterina

    2014-12-01

    Age-related reductions in strength and power are considered to negatively impact balance control, but the existence of a direct association is still an issue of debate. This is possibly due to the fact that balance assessment is complex, reflects different underlying physiologic mechanisms and involves quantitative measurements of postural sway or timing of performance during balance tasks. The present study evaluated the moderator effect of static postural control on the association of power and strength with dynamic balance tasks. Fifty-seven healthy 65-75 year old individuals performed tests of dynamic functional balance (walking speed under different conditions) and of strength, power and static postural control. Dynamic balance performance (walking speed) was associated with lower limb strength and power, as well as postural control under conditions requiring postural adjustments (narrow surface walking r(2) = 0.31, p balance tasks. Practical implications for assessment and training are discussed.

  3. Electric power balance sheet 2013

    International Nuclear Information System (INIS)

    2014-01-01

    The mission of RTE, the French electricity Transportation grid, a public service assignment, is to balance the electricity supply and demand in real time. This report presents RTE's technical results for the year 2013: stabilisation of the electricity consumption in France, high level of hydropower generation, fast evolution of the European power network, electricity markets in a transition situation, adaptation of RTE's network to the evolutions of the energy system

  4. Tandem mirror reactor power balance studies

    International Nuclear Information System (INIS)

    Gorker, G.E.; Perkins, L.J.

    1985-01-01

    A tandem mirror reactor (TMR) power plant balance model has been developed and is now being used as a computer aid for performing parametric studies. End-cell power injection into the plasma and the physics thermal Q are used to determine the fusion power. About 80% of the fusion power is transferred by high-energy neutrons to the blanket modules and structures. The other 20% of the fusion power in the high-energy alpha particles is used to heat the deuterium-tritium (D-T) plasma. Most of the plasma-ionized particles transfer their energy to the halo dumps and direct converters. The plant efficiency is calculated for three different system cycles: (1) the pressurized water/saturated steam cycle; (2) the superheated steam cycle; and (3) the more complex superheat/reheat cycle. There is a signficiant improvement in plant efficiency as the electrical power multiplication factor and steam cycle efficiency increases

  5. How the President and Senate Affect the Balance of Power in the

    OpenAIRE

    Gisela Sin; Arthur Lupia

    2005-01-01

    Can the President or the Senate affect the balance of power in the House? We find that they can. Our answer comes from a model that links House leadership decisions to the constitutional requirement to build lawmaking coalitions with the Senate and President. Changing the ideal point of a non-House actor, while holding constant the ideal point of all House members, can alter the House’s balance of power. Power shifts because changes in the Senate or President can reshape the set of achievable...

  6. Initial experience gained with the balance-group system of the Swiss power supply legislation

    International Nuclear Information System (INIS)

    Waldner, M.; Rechsteiner, S.

    2010-01-01

    This article takes a look at the initial experience gained with the Swiss balance-group system. This system was introduced within the framework of Swiss power supply legislation (StromVG - Stromversorgungsgesetz). The balance-group system was considered to be an essential precondition for the implementation of an energy trading business in a liberalised power market. The associated rights and responsibilities and the economic risks involved are discussed in detail. The partners and structures involved in such a balance-group are looked at and basic models for the associated contracts are examined. The relationship between balance-groups and the national power grid Swissgrid are discussed

  7. Network Condition Based Adaptive Control and its Application to Power Balancing in Electrical Grids

    DEFF Research Database (Denmark)

    Pedersen, Rasmus; Findrik, Mislav; Sloth, Christoffer

    2017-01-01

    To maintain a reliable and stable power grid there must be balance between consumption and production. To achieve power balance in a system with high penetration of distributed renewable resources and flexible assets, these individual system can be coordinated through a control unit to become part...... of the power balancing effort. Such control strategies require communication networks for exchange of control loop information. In this work, we show how a congested communication network can have a dramatic impact on the control performance of such a power balancing controller. To alleviate potential...

  8. Cortical processes associated with continuous balance control as revealed by EEG spectral power.

    Science.gov (United States)

    Hülsdünker, T; Mierau, A; Neeb, C; Kleinöder, H; Strüder, H K

    2015-04-10

    Balance is a crucial component in numerous every day activities such as locomotion. Previous research has reported distinct changes in cortical theta activity during transient balance instability. However, there remains little understanding of the neural mechanisms underlying continuous balance control. This study aimed to investigate cortical theta activity during varying difficulties of continuous balance tasks, as well as examining the relationship between theta activity and balance performance. 37 subjects completed nine balance tasks with different levels of surface stability and base of support. Throughout the balancing task, electroencephalogram (EEG) was recorded from 32 scalp locations. ICA-based artifact rejection was applied and spectral power was analyzed in the theta frequency band. Theta power increased in the frontal, central, and parietal regions of the cortex when balance tasks became more challenging. In addition, fronto-central and centro-parietal theta power correlated with balance performance. This study demonstrates the involvement of the cerebral cortex in maintaining upright posture during continuous balance tasks. Specifically, the results emphasize the important role of frontal and parietal theta oscillations in balance control. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. 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)

  10. Market integration of wind power in electricity system balancing

    DEFF Research Database (Denmark)

    Sorknæs, Peter; Andersen, Anders N.; Tang, Jens

    2013-01-01

    In most countries markets for electricity are divided into wholesale markets on which electricity is traded before the operation hour, and real-time balancing markets to handle the deviations from the wholesale trading. So far, wind power has been sold only on the wholesale market and has been...... known to increase the need for balancing. This article analyses whether wind turbines in the future should participate in the balancing markets and thereby play a proactive role. The analysis is based on a real-life test of proactive participation of a wind farm in West Denmark. It is found...... that the wind farm is able to play a proactive role regarding downward regulation and thereby increase profits....

  11. Dual Decomposition for Large-Scale Power Balancing

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus; Jørgensen, John Bagterp; Vandenberghe, Lieven

    2013-01-01

    Dual decomposition is applied to power balancing of exible thermal storage units. The centralized large-scale problem is decomposed into smaller subproblems and solved locallyby each unit in the Smart Grid. Convergence is achieved by coordinating the units consumption through a negotiation...

  12. Design of Electricity Markets for Efficient Balancing of Wind Power Generation

    OpenAIRE

    Scharff, Richard

    2015-01-01

    Deploying wind power to a larger extent is one solution to reduce negative environmental impacts of electric power supply. However, various challenges are connected with increasing wind power penetration levels. From the perspective of transmission system operators, this includes balancing of varying as well as - to some extent - uncertain generation levels. From the perspective of power generating companies, changes in the generation mix will affect the market's merit order and, hence, their...

  13. Reusing balanced power flow object components for developing harmonic power flow

    Energy Technology Data Exchange (ETDEWEB)

    Nadarajah, S. [Peninsular Malaysia Electric Utility Co., Kuala Lumpur (Malaysia). Tenaga Nasional Berhad; Nor, K.M.; Abdel-Akher, M. [Malaysia Univ., Kuala Lumpur (Malaysia). Dept. of Electrical Engineering

    2005-07-01

    Harmonic power flows are used to examine the effects of nonlinear loads on power systems. In this paper, component technology was re-used for the development of a harmonic power flow. The object-oriented power system model (OO-PSM) was developed separately from a solution algorithm. Nodes, lines, and transformers were modelled as entity objects by classes. Power flow solution algorithms were modelled as control objects and encapsulated inside independent software components within the power system component software architecture (PS-COM). Both the OO-PSM and the PS-COM of the balanced power flow were re-used for developing the proposed harmonic power flow. A no-interaction hypothesis was used to consider both fundamental voltages and nonlinear device data dependence. A direct solution voltage node method was also used. The accuracy of the method was demonstrated using IEEE 14 bus and 30 bus test systems. It was concluded that component technology can be used to develop harmonic power flow programs. 7 refs., 2 tabs., 9 figs.

  14. Sensitivity of sensor-based sit-to-stand peak power to the effects of training leg strength, leg power and balance in older adults.

    Science.gov (United States)

    Regterschot, G Ruben H; Folkersma, Marjanne; Zhang, Wei; Baldus, Heribert; Stevens, Martin; Zijlstra, Wiebren

    2014-01-01

    Increasing leg strength, leg power and overall balance can improve mobility and reduce fall risk. Sensor-based assessment of peak power during the sit-to-stand (STS) transfer may be useful for detecting changes in mobility and fall risk. Therefore, this study investigated whether sensor-based STS peak power and related measures are sensitive to the effects of increasing leg strength, leg power and overall balance in older adults. A further aim was to compare sensitivity between sensor-based STS measures and standard clinical measures of leg strength, leg power, balance, mobility and fall risk, following an exercise-based intervention. To achieve these aims, 26 older adults (age: 70-84 years) participated in an eight-week exercise program aimed at improving leg strength, leg power and balance. Before and after the intervention, performance on normal and fast STS transfers was evaluated with a hybrid motion sensor worn on the hip. In addition, standard clinical tests (isometric quadriceps strength, Timed Up and Go test, Berg Balance Scale) were performed. Standard clinical tests as well as sensor-based measures of peak power, maximal velocity and duration of normal and fast STS showed significant improvements. Sensor-based measurement of peak power, maximal velocity and duration of normal STS demonstrated a higher sensitivity (absolute standardized response mean (SRM): ≥ 0.69) to the effects of training leg strength, leg power and balance than standard clinical measures (absolute SRM: ≤ 0.61). Therefore, the presented sensor-based method appears to be useful for detecting changes in mobility and fall risk. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. The Effects of Local Vibration on Balance, Power, and Self-Reported Pain After Exercise.

    Science.gov (United States)

    Custer, Lisa; Peer, Kimberly S; Miller, Lauren

    2017-05-01

    Muscle fatigue and acute muscle soreness occur after exercise. Application of a local vibration intervention may reduce the consequences of fatigue and soreness. To examine the effects of a local vibration intervention after a bout of exercise on balance, power, and self-reported pain. Single-blind crossover study. Laboratory. 19 healthy, moderately active subjects. After a 30-min bout of full-body exercise, subjects received either an active or a sham vibration intervention. The active vibration intervention was performed bilaterally over the muscle bellies of the triceps surae, quadriceps, hamstrings, and gluteals. At least 1 wk later, subjects repeated the bout, receiving the other vibration intervention. Static balance, dynamic balance, power, and self-reported pain were measured at baseline, after the vibration intervention, and 24 h postexercise. After the bout of exercise, subjects had reduced static and dynamic balance and increased self-reported pain regardless of vibration intervention. There were no differences between outcome measures between the active and sham vibration conditions. The local vibration intervention did not affect balance, power, or self-reported pain.

  16. A peaking-regulation-balance-based method for wind & PV power integrated accommodation

    Science.gov (United States)

    Zhang, Jinfang; Li, Nan; Liu, Jun

    2018-02-01

    Rapid development of China’s new energy in current and future should be focused on cooperation of wind and PV power. Based on the analysis of system peaking balance, combined with the statistical features of wind and PV power output characteristics, a method of comprehensive integrated accommodation analysis of wind and PV power is put forward. By the electric power balance during night peaking load period in typical day, wind power installed capacity is determined firstly; then PV power installed capacity could be figured out by midday peak load hours, which effectively solves the problem of uncertainty when traditional method hard determines the combination of the wind and solar power simultaneously. The simulation results have validated the effectiveness of the proposed method.

  17. Thermal Storage Power Balancing with Model Predictive Control

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus; Poulsen, Niels Kjølstad; Madsen, Henrik

    2013-01-01

    The method described in this paper balances power production and consumption with a large number of thermal loads. Linear controllers are used for the loads to track a temperature set point, while Model Predictive Control (MPC) and model estimation of the load behavior are used for coordination....... The total power consumption of all loads is controlled indirectly through a real-time price. The MPC incorporates forecasts of the power production and disturbances that influence the loads, e.g. time-varying weather forecasts, in order to react ahead of time. A simulation scenario demonstrates...

  18. Storage and balancing synergies in a fully or highly renewable pan-European power system

    International Nuclear Information System (INIS)

    Rasmussen, Morten Grud; Andresen, Gorm Bruun; Greiner, Martin

    2012-01-01

    Through a parametric time-series analysis of 8 years of hourly data, we quantify the storage size and balancing energy needs for highly and fully renewable European power systems for different levels and mixes of wind and solar energy. By applying a dispatch strategy that minimizes the balancing energy needs for a given storage size, the interplay between storage and balancing is quantified, providing a hard upper limit on their synergy. An efficient but relatively small storage reduces balancing energy needs significantly due to its influence on intra-day mismatches. Furthermore, we show that combined with a low-efficiency hydrogen storage and a level of balancing equal to what is today provided by storage lakes, it is sufficient to meet the European electricity demand in a fully renewable power system where the average power generation from combined wind and solar exceeds the demand by only a few percent. - Highlights: ► We model a wind and solar based European power system with storage and balancing. ► We find that storage needs peaks when average renewable generation matches load. ► We find strong synergetic effects when combining storage and balancing. ► We study the effects of a storage capable of storing 6 h average use. ► We find a realisable fully renewable scenario based on wind, solar and hydro power.

  19. Power and particle balance during neutral beam injection in TFTR

    International Nuclear Information System (INIS)

    Pitcher, C.S.; Budny, R.V.; Hill, K.W.; Kilpatrick, S.J.; Manos, D.M.; Medley, S.S.; Ramsey, A.T.

    1991-05-01

    Detailed boundary plasma measurements on TFTR have been made during a NBI power scan in the range P tot = 1MW--20MW in the L-mode regime. The behavior of the plasma density left-angle n e right-angle, radiated power P rad , carbon and deuterium fluxes Γ C , Γ D , and Ζ eff can be summarized as, left-angle n e right-angle ∝ P tot 1/2 , P rad , Γ C , Γ D ∝ P tot , and Ζ eff ∼ constant. It is shown that central fuelling by the neutral beams plays a minor role in the particle balance of the discharge. More important is the NBI role in the power balance. The TFTR data during NBI originate primarily at the graphite limiter

  20. Dynamic Balanced Scorecard for companies in the business field of power supply; Dynamic Balanced Scorecard fuer Unternehmen im Geschaeftsfeld der dezentralen Energieversorgung

    Energy Technology Data Exchange (ETDEWEB)

    Hollmann, M.; Roy, I. [Paderborn Univ. (Germany). Lehrstuhl fuer Nachhaltige Energiekonzepte

    2006-06-19

    Due to deregulation and liberalisation of the power market and due to the opting out of the nuclear energy, the decentralized power supply increasingly gains in importance in comparison to the classical power supply. Thus, the entrepreneur who wants to engage in the decentralized power supply needs a management tool for conversion and supervision his strategy. A pertinent means for this already is the Dynamic Balanced Scorecard. By means of an evaluation of a simple balanced scorecard, the entrepreneur realizes his vision and strategy in order to determine the success-critical factors. These success-critical factors are related together in a causal chain. By this, the entrepreneur can recognize, what has to be done in order to act successfully on the market, and in order to secure the success on a long-term basis. The modelling of the Dynamic balanced Scorecard enables the examination of the corporate strategy, before it is implemented in the enterprise. Thus, the entrepreneur saves time and minimizes the corporate risk.

  1. Economic feasibility of pipe storage and underground reservoir storage options for power-to-gas load balancing

    International Nuclear Information System (INIS)

    Budny, Christoph; Madlener, Reinhard; Hilgers, Christoph

    2015-01-01

    Highlights: • Study of cost effectiveness of power-to-gas and storage of H 2 and renewable methane. • NPV analysis and Monte Carlo simulation to address fuel and electricity price risks. • Gas sale is compared with power and gas market arbitrage and balancing market gains. • Power-to-gas for linking the balancing markets for power and gas is not profitable. • Pipe storage is the preferred option for temporal arbitrage and balancing energy. - Abstract: This paper investigates the economic feasibility of power-to-gas (P2G) systems and gas storage options for both hydrogen and renewable methane. The study is based on a techno-economic model in which the net present value (NPV) method and Monte Carlo simulation of risks and price forward curves for the electricity and the gas market are used. We study three investment cases: a Base Case where the gas is directly sold in the market, a Storage & Arbitrage Case where temporal arbitrage opportunities between the electricity and the gas market are exploited, and a Storage & Balancing Case where the balancing markets (secondary reserve market for electricity, external balancing market for natural gas) are addressed. The optimal type and size of different centralized and decentralized storage facilities are determined and compared with each other. In a detailed sensitivity and cost analysis, we identify the key factors which could potentially improve the economic viability of the technological concepts assessed. We find that the P2G system used for bridging the balancing markets for power and gas cannot be operated profitably. For both, temporal arbitrage and balancing energy, pipe storage is preferred. Relatively high feed-in tariffs (100 € MW −1 for hydrogen, 130 € MW −1 for methane) are required to render pipe storage for P2G economically viable

  2. Generalized balanced power diagrams for 3D representations of polycrystals

    DEFF Research Database (Denmark)

    Alpers, Andreas; Brieden, Andreas; Gritzmann, Peter

    2015-01-01

    Characterizing the grain structure of polycrystalline material is an important task in material science. The present paper introduces the concept of generalized balanced power diagrams as a concise alternative to voxelated mappings. Here, each grain is represented by (measured approximations of...

  3. Tradeoffs in the design of health plan payment systems: Fit, power and balance.

    Science.gov (United States)

    Geruso, Michael; McGuire, Thomas G

    2016-05-01

    In many markets, including the new U.S. Marketplaces, health insurance plans are paid by risk-adjusted capitation, sometimes combined with reinsurance and other payment mechanisms. This paper proposes a framework for evaluating the de facto insurer incentives embedded in these complex payment systems. We discuss fit, power and balance, each of which addresses a distinct market failure in health insurance. We implement empirical metrics of fit, power, and balance in a study of Marketplace payment systems. Using data similar to that used to develop the Marketplace risk adjustment scheme, we quantify tradeoffs among the three classes of incentives. We show that an essential tradeoff arises between the goals of limiting costs and limiting cream skimming because risk adjustment, which is aimed at discouraging cream-skimming, weakens cost control incentives in practice. A simple reinsurance system scores better on our measures of fit, power and balance than the risk adjustment scheme in use in the Marketplaces. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Discontinuation of the peaceful use of nuclear power and a balanced economic situation

    International Nuclear Information System (INIS)

    Lippert, M.

    2002-01-01

    The amendment to the German Atomic Energy Act (AtG) serves to terminate, in a legislative approach, the use of nuclear power for energy generation. The federal government considers the use of nuclear power 'economically unreasonable' irrespective of the fact that nuclear power makes important contributions to the protection of the climate and, above all, to safe, cost-efficient, and non-polluting supplies of power. Opting out of the use of nuclear power raises the question of the consequences this step has for the power economy and the economy as a whole. Giving up nuclear power in electricity generation would affect the objectives of a safe, economic, and non-polluting energy supply. In view of the outstanding importance of energy supply to the whole economy, the - constitutional - question arises whether opting out of the use of nuclear power not only jeopardizes the supply of energy, but may result even in a disruption of the balance of the entire economy in the sense of Art. 109, Para. 2 of the German Basic Law, under which the federation and the federal states are obliged to bear in mind the requirements of a balanced overall economy. In a differentiated interpretation of Article 109, Para. 2 of the Basic Law, the government is required, also outside of budget management aspects, to refrain from measures upsetting the balance of the entire conomy. Inter alia, this could have the consequence of not opting out of the peaceful use of nuclear power. It is up to the competent government agencies to decide on measures to control this development. For this purpose, a number of variants are available which may range between stretching out the period of time of the opt-out procedure and giving up this opt-out altogether. (orig.) [de

  5. The impact of European balancing rules on wind power economics and on short-term bidding strategies

    International Nuclear Information System (INIS)

    Chaves-Ávila, J.P.; Hakvoort, R.A.; Ramos, A.

    2014-01-01

    Wind power represents a significant percentage of the European generation mix and this will increase to fulfill the renewable energy targets. Different balancing rules are applied to wind power among the countries; for instance, to what extent wind power producers (WPPs) are responsible for the energy imbalances and how those imbalances are penalized. This paper discusses those different rules and evaluates their effects on WPP bidding strategies. To do so, a quantitative analysis is presented for an offshore wind farm, considering the differences in the balancing rules and prices of Belgium, Denmark, Germany and the Netherlands. The quantitative approach consists of a stochastic optimization model that maximizes the profits of a WPP by trading in different markets (day-ahead and intraday) and computes the final energy delivered. The model considers uncertainties of most important parameters such as wind energy forecasts and prices at different time frames. The results show that the imbalance pricing design and the allocation of balance responsibility significantly affect WPP’ revenues. Additionally, WPPs deviate differently from the expected energy depending on the balancing rules, which can impact the system. Furthermore, these balancing rules should be considered with other market regulations, such as the design of support schemes. - Highlights: • European countries apply different imbalance pricing rules. • The allocation of balance responsibility to wind power varies between the countries. • A stochastic optimization model is used to compare the effect of balancing rules. • Balancing rules have an important impact on wind generators bidding strategies. • Balancing rules have also an effect on the system imbalances

  6. Energy Balance of Nuclear Power Generation. Life Cycle Analyses of Nuclear Power

    International Nuclear Information System (INIS)

    Wallner, A.; Wenisch, A.; Baumann, M.; Renner, S.

    2011-01-01

    The accident at the Japanese nuclear power plant Fukushima in March 2011 triggered a debate about phasing out nuclear energy and the safety of nuclear power plants. Several states are preparing to end nuclear power generation. At the same time the operational life time of many nuclear power plants is reaching its end. Governments and utilities now need to take a decision to replace old nuclear power plants or to use other energy sources. In particular the requirement of reducing greenhouse gas emissions (GHG) is used as an argument for a higher share of nuclear energy. To assess the contribution of nuclear power to climate protection, the complete life cycle needs to be taken into account. Some process steps are connected to high CO2 emissions due to the energy used. While the processes before and after conventional fossil-fuel power stations can contribute up to 25% of direct GHG emission, it is up to 90 % for nuclear power (Weisser 2007). This report aims to produce information about the energy balance of nuclear energy production during its life cycle. The following key issues were examined: How will the forecasted decreasing uranium ore grades influence energy intensity and greenhouse emissions and from which ore grade on will no energy be gained anymore? In which range can nuclear energy deliver excess energy and how high are greenhouse gas emissions? Which factors including ore grade have the strongest impact on excess energy? (author)

  7. Learning Responsibility and Balance of Power

    Directory of Open Access Journals (Sweden)

    Şefika Sümeyye Çam

    2014-01-01

    Full Text Available This qualitative study aims to determine teacher perspectives on learning responsibility and balance of power. The research design is case study which was conducted on four primary school teachers. The data were collected with semi-structured interviews and the data obtained were analyzed with categorical analysis, a type of content analysis. The findings suggest that teachers think that learner should be at the center of teaching with LCT and they are incapable of applying learner-center teaching. It has been found that the class size and loaded teaching programs prevent them to apply LCT. Therefore, there have been some recommendations about the LCT by the researchers of the study.

  8. Cross-cultural differences in sibling power balance and its concomitants across three age periods

    NARCIS (Netherlands)

    Buist, K.L.; Metindogan, A.; Coban, S.; Watve, S.; Paranipe, A.; Koot, Hans M.; Van Lier, P.; Branje, Susan; Meeus, W.H.J.

    2017-01-01

    We examined cross-cultural differences in (1) sibling power balance and (2) the associations between sibling power balance and internalizing and externalizing problems in three separate cross-cultural studies (early childhood, late childhood, and adolescence). The early childhood samples consisted

  9. Using the Power Balance Wristband to Improve Students' Research-Design Skills

    Science.gov (United States)

    Lawson, Timothy J.; Blackhart, Ginette C.; Gialopsos, Brooke M.

    2016-01-01

    We describe an exercise involving the power balance wristband (PBW) designed to enhance students' ability to design scientific tests. An instructor demonstrated that the PBW improved a student's balance, strength, and flexibility and invited students to design and conduct a brief scientific test of the PBW. Research methods students who…

  10. Cross-Cultural Differences in Sibling Power Balance and Its Concomitants across Three Age Periods

    Science.gov (United States)

    Buist, Kirsten L.; Metindogan, Aysegül; Coban, Selma; Watve, Sujala; Paranjpe, Analpa; Koot, Hans M.; van Lier, Pol; Branje, Susan J. T.; Meeus, Wim H. J.

    2017-01-01

    We examined cross-cultural differences in (1) sibling power balance and (2) the associations between sibling power balance and internalizing and externalizing problems in three separate cross-cultural studies (early childhood, late childhood, and adolescence). The "early childhood samples" consisted of 123 Turkish and 128 Dutch mothers…

  11. The future role of nuclear power in the global energy balance

    International Nuclear Information System (INIS)

    Semenov, B.A.; Guthrie, D.; Tatsuta, Y.

    1991-01-01

    A sound judgement on the role of nuclear power in the global energy balance within the time span of the next 30 years should logically be based on the consideration of at least a number of factors such as global trends in energy and electricity demand, practically available or estimated sources of supply, major requirements that these energy sources should meet, nuclear power's own potential, a realistic assessment of nuclear power's present status, and problems related to nuclear power. The conclusion of such an analysis is that nuclear power will retain, and may even enhance, its position as an important element in the world's energy supply mix

  12. Balance-of-plant options for the Heat-Pipe Power System

    International Nuclear Information System (INIS)

    Berte, M.; Capell, B.

    1997-09-01

    The Heat-Pipe Power System (HPS) is a near-term, low-cost space fission power system with the potential for utilizing various option for balance-of-plant options. The following options have been studied: a low-power thermoelectric design (14-kWe output), a small Brayton cycle system (60--75 kWe), and a large Brayton cycle system (250 kWe). These systems were analyzed on a preliminary basis, including mass, volume, and structure calculations. These analyses have shown that the HPS system can provide power outputs from 10--250 kWe with specific powers of ∼ 14 W/kg for a 14-kWe model to ∼ 100 W/kg for a 250-kWe model. The system designs considered in this study utilize a common component base to permit easy expansion and development

  13. Bahrain and the global balance of power after the Arab spring

    OpenAIRE

    Andersen, Lars Erslev

    2012-01-01

    The global balance of power is changing, and the role of the US as the only superpower is being challenged by emerging new powers and a still more powerful China. Nowhere is this more apparent than in the Persian Gulf. Two wars in Afghanistan and Iraq and continually rising debt have meant that the position of the US has declined. At the same time, Asian states are increasing their economic expansion in the Persian Gulf. Increasing political influence, including a bigger role in hard security...

  14. Power Loss Minimization for Transformers Connected in Parallel with Taps Based on Power Chargeability Balance

    Directory of Open Access Journals (Sweden)

    Álvaro Jaramillo-Duque

    2018-02-01

    Full Text Available In this paper, a model and solution approach for minimizing internal power losses in Transformers Connected in Parallel (TCP with tap-changers is proposed. The model is based on power chargeability balance and seeks to keep the load voltage within an admissible range. For achieving this, tap positions are adjusted in such a way that all TCP are set in similar/same power chargeability. The main contribution of this paper is the inclusion of several construction features (rated voltage, rated power, voltage ratio, short-circuit impedance and tap steps in the minimization of power losses in TCP that are not included in previous works. A Genetic Algorithm (GA is used for solving the proposed model that is a system of nonlinear equations with discrete decision variables. The GA scans different sets for tap positions with the aim of balancing the power supplied by each transformer to the load. For this purpose, a fitness function is used for minimizing two conditions: The first condition consists on the mismatching between power chargeability for each transformer and a desired chargeability; and the second condition is the mismatching between the nominal load voltage and the load voltage obtained by changing the tap positions. The proposed method is generalized for any given number of TCP and was implemented for three TCP, demonstrating that the power losses are minimized and the load voltage remains within an admissible range.

  15. Voltage balancing in modular energy storage of power supply for micro resistance welding

    Directory of Open Access Journals (Sweden)

    Kozhushko Yu. V.

    2017-10-01

    Full Text Available Micro resistance welding is one of the most effective ways to obtain permanent joints of metal parts. The quality of welded joints strongly depends on the characteristics of the power supply of welding equipment. The power supplies for micro resistance welding based on Energy Storage topology have a softer impact on the network than the ones based on Direct Energy topology. The use of supercapacitors for Energy Storage type power supplies makes it possible to reduce the dimensions of welding equipment and to improve its technical parameters. However, the feature of the supercapacitors is low value of the nominal voltage, which usually does not exceed 3 V. To provide higher voltage, the modules of supercapacitors connected in series are designed. In order to extend the life time of such modules, a voltage balancing system is required. A circuit for balancing the voltage of a modular supercapacitor energy storage of a power supply for micro resistance welding is proposed. The fragments of calculation of control units of a supercapacitor module cell are given. The simulation of the balancing circuit operation is carried out and time charts of the supercapacitor charge process are obtained. The operability and effectiveness of the proposed solution is confirmed. The advantage of the proposed circuit is the possibility of obtaining the high efficiency because of returning the excessive energy of the module cell back into the power supply.

  16. Efficacy of the Power Balance Silicone Wristband: a single-blind, randomized, triple placebo-controlled study.

    Science.gov (United States)

    Pothier, David D; Thiel, Gundula; Khoo, S G; Dillon, Wanda A; Sulway, Shaleen; Rutka, John A

    2012-06-01

    The Power Balance Silicone Wristband (Power Balance LLC, Laguna Niguel, CA) (power balance band; PBB) consists of a silicone wristband, incorporating two holograms, which is meant to confer improvements in balance on the wearer. Despite its popularity, the PBB has become somewhat controversial, with a number of articles being published in the news media regarding its efficacy. The PBB has not been formally evaluated but remains popular, largely based on anecdotal evidence. This study subjectively and objectively measured the effects of the PBB on balance in normal participants. A prospective, single-blind, randomized, triple placebo-controlled crossover study was undertaken. Twenty participants underwent measurement using the modified Test of Sensory Interaction on Balance (mCTSIB) and gave subjective feedback (visual analogue scale [VAS]) for each of four band conditions: no band, a silicone band, a deactivated PBB, and the PBB. Participants acted as their own controls. The mean of the four mCTSIB conditions (eyes open and closed on both firm and compliant surfaces) was calculated. This mean value and condition 4 of the mCTSIB were compared between band conditions using path length (PL) and root mean square (RMS) as outcome measures. No significant differences were found between band conditions for PL (p  =  .91 and p  =  .94, respectively) and RMS (p  =  .85 and p  =  .96, respectively). VASs also showed no difference between bands (p  =  .25). The PBB appears to have no effect on mCTSIB or VAS measurements of balance.

  17. Improve SSME power balance model

    Science.gov (United States)

    Karr, Gerald R.

    1992-01-01

    Effort was dedicated to development and testing of a formal strategy for reconciling uncertain test data with physically limited computational prediction. Specific weaknesses in the logical structure of the current Power Balance Model (PBM) version are described with emphasis given to the main routing subroutines BAL and DATRED. Selected results from a variational analysis of PBM predictions are compared to Technology Test Bed (TTB) variational study results to assess PBM predictive capability. The motivation for systematic integration of uncertain test data with computational predictions based on limited physical models is provided. The theoretical foundation for the reconciliation strategy developed in this effort is presented, and results of a reconciliation analysis of the Space Shuttle Main Engine (SSME) high pressure fuel side turbopump subsystem are examined.

  18. A Magnetic-Balanced Inductive Link for the Simultaneous Uplink Data and Power Telemetry.

    Science.gov (United States)

    Gong, Chen; Liu, Dake; Miao, Zhidong; Li, Min

    2017-08-02

    When using the conventional two-coil inductive link for the simultaneous wireless power and data transmissions in implantable biomedical sensor devices, the strong power carrier could overwhelm the uplink data signal and even saturate the external uplink receiver. To address this problem, we propose a new magnetic-balanced inductive link for our implantable glaucoma treatment device. In this inductive link, an extra coil is specially added for the uplink receiving. The strong power carrier interference is minimized to approach zero by balanced canceling of the magnetic field of the external power coil. The implant coil is shared by the wireless power harvesting and the uplink data transmitting. Two carriers (i.e., 2-MHz power carrier and 500-kHz uplink carrier) are used for the wireless power transmission and the uplink data transmission separately. In the experiments, the prototype of this link achieves as high as 65.72 dB improvement of the signal-to-interference ratio (SIR) compared with the conventional two-coil inductive link. Benefiting from the significant improvement of SIR, the implant transmitter costs only 0.2 mW of power carrying 50 kbps of binary phase shift keying data and gets a bit error rate of 1 × 10 - 7 , even though the coupling coefficient is as low as 0.005. At the same time, 5 mW is delivered to the load with maximum power transfer efficiency of 58.8%. This magnetic-balanced inductive link is useful for small-sized biomedical sensor devices, which require transmitting data and power simultaneously under ultra-weak coupling.

  19. A Magnetic-Balanced Inductive Link for the Simultaneous Uplink Data and Power Telemetry

    Directory of Open Access Journals (Sweden)

    Chen Gong

    2017-08-01

    Full Text Available When using the conventional two-coil inductive link for the simultaneous wireless power and data transmissions in implantable biomedical sensor devices, the strong power carrier could overwhelm the uplink data signal and even saturate the external uplink receiver. To address this problem, we propose a new magnetic-balanced inductive link for our implantable glaucoma treatment device. In this inductive link, an extra coil is specially added for the uplink receiving. The strong power carrier interference is minimized to approach zero by balanced canceling of the magnetic field of the external power coil. The implant coil is shared by the wireless power harvesting and the uplink data transmitting. Two carriers (i.e., 2-MHz power carrier and 500-kHz uplink carrier are used for the wireless power transmission and the uplink data transmission separately. In the experiments, the prototype of this link achieves as high as 65.72 dB improvement of the signal-to-interference ratio (SIR compared with the conventional two-coil inductive link. Benefiting from the significant improvement of SIR, the implant transmitter costs only 0.2 mW of power carrying 50 kbps of binary phase shift keying data and gets a bit error rate of 1 × 10 − 7 , even though the coupling coefficient is as low as 0.005. At the same time, 5 mW is delivered to the load with maximum power transfer efficiency of 58.8%. This magnetic-balanced inductive link is useful for small-sized biomedical sensor devices, which require transmitting data and power simultaneously under ultra-weak coupling.

  20. Balance of the LVC plant with increase in 15 % of power; Balance de planta de la CLV con aumento del 15 % de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, J.J.; Hernandez, J.L.; Perusquia, R.; Castillo, A.; Montes, J.L. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: jjortiz@nuclear.inin.mx

    2005-07-01

    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)

  1. Relationship of the Functional Movement Screen In-Line Lunge to Power, Speed, and Balance Measures

    OpenAIRE

    Hartigan, Erin H.; Lawrence, Michael; Bisson, Brian M.; Torgerson, Erik; Knight, Ryan C.

    2014-01-01

    Background: The in-line lunge of the Functional Movement Screen (FMS) evaluates lateral stability, balance, and movement asymmetries. Athletes who score poorly on the in-line lunge should avoid activities requiring power or speed until scores are improved, yet relationships between the in-line lunge scores and other measures of balance, power, and speed are unknown. Hypothesis: (1) Lunge scores will correlate with center of pressure (COP), maximum jump height (MJH), and 36.6-meter sprint time...

  2. Power-balance analysis of muon-catalyzed fusion-fission hybrid reactor systems

    International Nuclear Information System (INIS)

    Miller, R.L.; Krakowski, R.A.

    1985-01-01

    A power-balance model of a muon-catalyzed fusion system in the context of a fission-fuel factory is developed and exercised to predict the required physics performance of systems competitive with either pure muon-catalyzed fusion systems or thermonuclear fusion-fission fuel factory hybrid systems

  3. An alternative approach for real-time balancing of electrical power systems

    NARCIS (Netherlands)

    Virag, A.; Jokic, A.; Lampropoulos, I.; Hermans, R.M.; Bosch, van den P.P.J.

    2012-01-01

    In this paper, we focus on the inefficiencies of current real-time balancing of power systems and propose an alternative solution. Our approach is based on the introduction of double-sided markets for the provision of secondary control and a market-based provision of primary control. We propose

  4. Power balance estimation in long duration discharges on QUEST

    International Nuclear Information System (INIS)

    Hanada, K.; Zushi, H.; Idei, H.

    2013-01-01

    Fully non-inductive plasma start-up was successfully achieved by using a well-controlled microwave on the spherical tokamak, QUEST. Non inductive plasmas could be maintained for approximately 3∼5 min, where power balance could be achieved in the view of monitoring of wall and cooling water temperature. Approximately 80% of the injected power could be detected by a calorimetric measurement and the residual power may be lost in two antenna systems to inject the well-controlled microwave. Almost more than 50% of injected power is deposited on the vacuum wall, not depending on the magnetic configuration. The power distribution to PFCs significantly depends on the magnetic configuration, however some of them is providing from energetic electrons, which have large poloidal orbits and are likely to deposit on the vessel in the low field side. (author)

  5. Application of balanced score card in the development of performance indicator system in nuclear power plant

    International Nuclear Information System (INIS)

    Shen Shuguang; Huang Fang; Fang Zhaoxia

    2013-01-01

    Performance indicator, which is one of ten performance monitoring tools recommended by WANO performance improvement model, has become an effective tool for performance improvement of nuclear power plant. At present, performance indicator system has been built in nuclear power plant. However, how to establish the performance indicator system that is reasonable and applicable for plant is still a question to be discussed. Performance indictor is closely tied to the strategic direction of a corporation by a balanced score card, and the performance indicator system is established from the point of performance management and strategic development. The performance indicator system of nuclear power plant is developed by introducing the balanced score card, and can be as a reference for other domestic nuclear power plants. (authors)

  6. Forecast of wind energy production and ensuring required balancing power

    International Nuclear Information System (INIS)

    Merkulov, M.

    2010-01-01

    The wind energy is gaining larger part of the energy mix around the world as well as in Bulgaria. Having in mind the irregularity of the wind, we are in front of a challenge for management of the power grid in new unknown conditions. The world's experience has proven that there could be no effective management of the grid without forecasting tools, even with small scale of wind power penetration. Application of such tools promotes simple management of large wind energy production and reduction of the quantities of required balancing powers. The share of the expenses and efforts for forecasting of the wind energy is incomparably small in comparison with expenses for keeping additional powers in readiness. The recent computers potential allow simple and rapid processing of large quantities of data from different sources, which provides required conditions for modeling the world's climate and producing sophisticated forecast. (author)

  7. 76 FR 2368 - Balance Power Systems, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Science.gov (United States)

    2011-01-13

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ER11-2331-000] Balance Power Systems, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for Blanket... proceeding of Balance Power Systems, LLC's application for market-based rate authority, with an accompanying...

  8. Balancing of a power-transmission shaft with the application of axial torque

    Science.gov (United States)

    Zorzi, E. S.; Flemming, D.

    1980-01-01

    Evaluation of power transmission shafting for high-speed balancing has shown that when axial torque is applied, the imbalance response is altered. An increase in synchronous excitation always occurs if the axial torque level is altered from the value used during balancing; this was the case even when the shaft was balanced with torque applied. The twisting of the long slender shaft produces a change in the imbalance distribution sufficient to disrupt the balanced state. This paper presents a review of the analytic development of a weighted least squares approach to influence coefficient balancing and a review of experimental results. The analytic approach takes advantage of the fact that the past testing has shown that the influence coefficients are not significantly affected by the application of axial torque. The 3.60-m (12-ft) long aluminum shaft, 7.62 cm (3 in.) in diameter was run through the first flexural critical speed at torque levels ranging from zero-torque to 903.8 N-M (8000 lb-in.) in 112.9 N-M (1000 lb-in.) increments. Good comparison was achieved between predicted and experimental results.

  9. TPSS plasma engineering studies: profile effects and plasma power balance

    International Nuclear Information System (INIS)

    Borowski, S.K.; Strickler, D.J.

    1985-01-01

    A computationally fast profile-averaged, steady-state plasma model has been developed to allow studies of radial effects in ignited and driven tokamak systems. This code was used to search for the smallest size tokamak consistent with power balance calculations

  10. Battery model for electrical power system energy balance

    Science.gov (United States)

    Hafen, D. P.

    1983-01-01

    A model to simulate nickel-cadmium battery performance and response in a spacecraft electrical power system energy balance calculation was developed. The voltage of the battery is given as a function of temperature, operating depth-of-charge (DOD), and battery state-of-charge. Also accounted for is charge inefficiency. A battery is modeled by analysis of the results of a multiparameter battery cycling test at various temperatures and DOD's.

  11. Preliminary study on power balance in the plasma of an experimental fusion reactor

    International Nuclear Information System (INIS)

    Tone, Tatsuzo; Yamato, Harumi

    1976-03-01

    The preliminary study on power balance in the plasma is described in the first-stage design of an experimental fusion reactor. The purpose is to show the ranges of plasma parameters for the design output of about 100 MW with an injection power less than 50 MW. The impurity is permitted to the extent of Zsub(eff) -- 5 to meet the design requirement. Influences of the uncertainty in scaling law on the power output and injection power are discussed, and also possibility of the self-ignition. (auth.)

  12. Balance and muscle power of children with Charcot-Marie-Tooth.

    Science.gov (United States)

    Silva, Tais R; Testa, Amanda; Baptista, Cyntia R J A; Marques, Wilson; Mattiello-Sverzut, Ana C

    2014-01-01

    In certain diseases, functional constraints establish a greater relationship with muscle power than muscle strength. However, in hereditary peripheral polyneuropathies, no such relationship was found in the literature. In children with Charcot-Marie-Tooth (CMT), to identify the impact of muscle strength and range of movement on the static/dynamic balance and standing long jump based on quantitative and functional variables. The study analyzed 19 participants aged between 6 and 16 years, of both genders and with clinical diagnoses of CMT of different subtypes. Anthropometric data, muscle strength of the lower limbs (hand-held dynamometer), ankle and knee range of movement, balance (Pediatric Balance Scale) and standing long jump distance were obtained by standardized procedures. For the statistical analysis, Pearson and Spearman correlation coefficients were used. There was a strong positive correlation between balance and the muscle strength of the right plantar flexors (r=0.61) and dorsiflexors (r=0.59) and a moderate correlation between balance and the muscle strength of inversion (r=0.41) and eversion of the right foot (r=0.44). For the long jump and range of movement, there was a weak positive correlation with right and left plantar flexion (r=0.20 and r=0.12, respectively) and left popliteal angle (r=0.25), and a poor negative correlation with left dorsiflexion (r=-0.15). The data on the patients analyzed suggests that the maintenance of distal muscle strength favors performance during balance tasks, while limitations in the range of movement of the legs seem not to be enough to influence the performance of the horizontal long jump.

  13. U.S. and Soviet Agriculture: The Shifting Balance of Power. Worldwatch Paper 51.

    Science.gov (United States)

    Brown, Lester R.

    Analysts of U.S.-Soviet balance of power usually focus on relative military strength. But other factors determine a country's overall power and influence. Among the most basic is a country's capacity to feed its people. By this measure the Soviet Union appears to be in deep trouble. Massive spending has increased Soviet military strength in recent…

  14. Balancing trust and power: a qualitative study of GPs perceptions and strategies for retaining patients in preventive health checks.

    Science.gov (United States)

    Broholm-Jørgensen, Marie; Guassora, Ann Dorrit; Reventlow, Susanne; Dalton, Susanne Oksbjerg; Tjørnhøj-Thomsen, Tine

    2017-03-01

    Little is known about how strategies of retaining patients are acted out by general practitioners (GPs) in the clinical encounter. With this study, we apply Grimens' (2009) analytical connection between trust and power to explore how trust and power appear in preventive health checks from the GPs' perspectives, and in what way trust and power affect and/or challenge strategies towards retaining patients without formal education. Data in this study were obtained through semi-structured interviews with GPs participating in an intervention project, as well as observations of clinical encounters. From the empirical data, we identified three dimensions of respect: respect for the patient's autonomy, respect for professional authority and respect as a mutual exchange. A balance of respect influenced trust in the relationship between GP and patients and the transfer of power in the encounter. The GPs articulated that a balance was needed in preventive health checks in order to establish trust and thus retain the patient in the clinic. One way this balance of respect was carried out was with the use of humour. To retain patients without formal education in the clinical encounter, the GPs balanced trust and power executed through three dimensions of respect. In this study, retaining patients was equivalent to maintaining a trusting relationship. A strategic use of the three dimensions of respect was applied to balance trust and power and thus build or maintain a trusting relationship with patients. KEY POINTS   Little is known about how strategies for retaining patients are acted out by GPs in preventive health checks.  •  Retaining patients requires a balance of trust and power, which is executed through three dimensions of respect by the GPs.  •  Challenges of recruiting and retaining patients in public health initiatives might be associated with the balance of respect.

  15. The Research of Utilization Hours of Coal-Fired Power Generation Units Based on Electric Energy Balance

    Science.gov (United States)

    Liu, Junhui; Yang, Jianlian; Wang, Jiangbo; Yang, Meng; Tian, Chunzheng; He, Xinhui

    2018-01-01

    With grid-connected scale of clean energy such as wind power and photovoltaic power expanding rapidly and cross-province transmission scale being bigger, utilization hours of coal-fired power generation units become lower and lower in the context of the current slowdown in electricity demand. This paper analyzes the influencing factors from the three aspects of demand, supply and supply and demand balance, and the mathematical model has been constructed based on the electric energy balance. The utilization hours of coal-fired power generation units have been solved considering the relationship among proportion of various types of power installed capacity, the output rate and utilization hours. By carrying out empirical research in Henan Province, the utilization hours of coal-fired units of Henan Province in 2020 has been achieved. The example validates the practicability and the rationality of the model, which can provide a basis for the decision-making for coal-fired power generation enterprises.

  16. A Location Selection Policy of Live Virtual Machine Migration for Power Saving and Load Balancing

    Directory of Open Access Journals (Sweden)

    Jia Zhao

    2013-01-01

    Full Text Available Green cloud data center has become a research hotspot of virtualized cloud computing architecture. And load balancing has also been one of the most important goals in cloud data centers. Since live virtual machine (VM migration technology is widely used and studied in cloud computing, we have focused on location selection (migration policy of live VM migration for power saving and load balancing. We propose a novel approach MOGA-LS, which is a heuristic and self-adaptive multiobjective optimization algorithm based on the improved genetic algorithm (GA. This paper has presented the specific design and implementation of MOGA-LS such as the design of the genetic operators, fitness values, and elitism. We have introduced the Pareto dominance theory and the simulated annealing (SA idea into MOGA-LS and have presented the specific process to get the final solution, and thus, the whole approach achieves a long-term efficient optimization for power saving and load balancing. The experimental results demonstrate that MOGA-LS evidently reduces the total incremental power consumption and better protects the performance of VM migration and achieves the balancing of system load compared with the existing research. It makes the result of live VM migration more high-effective and meaningful.

  17. A location selection policy of live virtual machine migration for power saving and load balancing.

    Science.gov (United States)

    Zhao, Jia; Ding, Yan; Xu, Gaochao; Hu, Liang; Dong, Yushuang; Fu, Xiaodong

    2013-01-01

    Green cloud data center has become a research hotspot of virtualized cloud computing architecture. And load balancing has also been one of the most important goals in cloud data centers. Since live virtual machine (VM) migration technology is widely used and studied in cloud computing, we have focused on location selection (migration policy) of live VM migration for power saving and load balancing. We propose a novel approach MOGA-LS, which is a heuristic and self-adaptive multiobjective optimization algorithm based on the improved genetic algorithm (GA). This paper has presented the specific design and implementation of MOGA-LS such as the design of the genetic operators, fitness values, and elitism. We have introduced the Pareto dominance theory and the simulated annealing (SA) idea into MOGA-LS and have presented the specific process to get the final solution, and thus, the whole approach achieves a long-term efficient optimization for power saving and load balancing. The experimental results demonstrate that MOGA-LS evidently reduces the total incremental power consumption and better protects the performance of VM migration and achieves the balancing of system load compared with the existing research. It makes the result of live VM migration more high-effective and meaningful.

  18. Assessing distorted trading incentives of balance responsible parties based on the example of the Swiss power system

    International Nuclear Information System (INIS)

    Scherer, Marc; Haubensak, Oliver; Staake, Thorsten

    2015-01-01

    Power systems require a continuous balance of supply and demand. In Europe, this task is shared between Balance Responsible Parties (BRPs) and Transmission System Operators (TSOs). For this purpose, the European electricity sector consists of several markets. Objective of this paper is to investigate distorted incentives that stem from loopholes in the market design which BRPs can use to undermine electricity balancing principles in favour of gaming opportunities between the domestic imbalance energy pricing and international wholesale markets. These incentives are evaluated using historical data from the Swiss power system which features a typical European imbalance pricing mechanism. The results imply that little effort would have been needed to make a good profit at the expense of system security. The major loophole arises from the interdependence between cross-border trading and national imbalance energy pricing. Bearing in mind the European Union's Third Energy Package, the importance of national balancing mechanisms will increase strongly. In this context, national remedies to cope with distorted incentives are outlined and the importance of harmonising balancing markets on an international level is elaborated. - Highlights: • We investigate distorted incentives that stem from loopholes in the market design. • Cross-border trading that undermines electricity balancing principles is evaluated. • Little effort is necessary to make a good profit at the expense of system security. • We examine historical data from the Swiss power system. • We outline remedies to limit the possibilities of profiting from potential loopholes.

  19. Simple annulus power balance in EBT-I

    International Nuclear Information System (INIS)

    Borowski, S.K.; Uckan, N.A.; Jaeger, E.F.; Kammash, T.

    1979-09-01

    An essential feature of the ELMO Bumpy Torus (EBT) concept is the presence of a relativistic electron annulus in each of the toroidal mirror sectors. These high beta annuli are formed and sustained by microwave heating and are of sufficient density and temperature that diamagnetic currents produce the necessary minimum in the magnetic field required for MHD stability of the toroidal core plasma. Because electron rings play an important role in confinement characteristics and performance of EBT, the trade-off between the quality of the confinement afforded by the rings and the power required to sustain the rings represents an important problem in a fusion reactor. Theoretical estimates of the microwave power required to sustain the annulus are found to be within a factor of 2 of the experimentally determined value. Scaling projections that are shown for both EBT-I and EBT-S enable one to examine the sensitivity of the annulus electron temperature as a function of core plasma density for various microwave power levels. The results are found to be sensitive to the details of the hot electron distribution function as well as geometric and scaling parameters. Improvements to the model are under way in order to increase its capability and accuracy in assessing the overall power balance

  20. Thermal power calibrations of the IPR-R1 TRIGA reactor by the calorimetric and the heat balance methods

    International Nuclear Information System (INIS)

    Mesquita, Amir Zacarias; Rezende, Hugo Cesar; Souza, Rose Mary Gomes do Prado

    2009-01-01

    Since the first nuclear reactor was built, a number of methodological variations have been evolved for the calibration of the reactor thermal power. Power monitoring of reactors is done by means of neutronic instruments, but its calibration is always done by thermal procedures. The purpose of this paper is to present the results of the thermal power calibration carried out on March 5th, 2009 in the IPR-R1 TRIGA reactor. It was used two procedures: the calorimetric and heat balance methods. The calorimetric procedure was done with the reactor operating at a constant power, with primary cooling system switched off. The rate of temperature rise of the water was recorded. The reactor power is calculate as a function of the temperature-rise rate and the system heat capacity constant. The heat balance procedure consists in the steady-state energy balance of the primary cooling loop of the reactor. For this balance, the inlet and outlet temperatures and the water flow in the primary cooling loop were measured. The heat transferred through the primary loop was added to the heat leakage from the reactor pool. The calorimetric method calibration presented a large uncertainty. The main source of error was the determination of the heat content of the system, due to a large uncertainty in the volume of the water in the system and a lack of homogenization of the water temperature. The heat balance calibration in the primary loop is the standard procedure for calibrating the power of the IPR-R1 TRIGA nuclear reactor. (author))

  1. 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)

  2. Changing Gender Roles, Shifting Power Balance and Long-distance Migration of Couples

    NARCIS (Netherlands)

    Smits, J.P.J.M.; Mulder, C.H.; Hooimeijer, P.

    2003-01-01

    Long-distance migration of couples requires joint decision-making within the household. The uneven power balance between men and women and traditional gender roles have given rise to the concepts of ‘tied stayer’ (usually the male partner) and ‘tied mover’ (usually the female). Since these

  3. Changing gender roles, shifting power balance and long-distance migration of couples

    NARCIS (Netherlands)

    Smits, J.; Mulder, C.H.; Hooimeijer, P.

    2003-01-01

    Long-distance migration of couples requires joint decision-making within the household. The uneven power balance between men and women and traditional gender roles have given rise to the concepts of 'tied stayer' (usually the male partner) and 'tied mover' (usually the female). Since these concepts

  4. The effect of six week mixed exercise (power & plyometric of dynamic balance in Takhti school physical education students in Babol city

    Directory of Open Access Journals (Sweden)

    Mohammadbagher Forghani

    2015-09-01

    Full Text Available The purpose of this research was the considering of the effect of six week mixed exercise (power & plyometric of dynamic balance in Takhti school physical education students in Babol city. 60 male athlete students (physical education, without record of injury in lower organs, head & auricle disorders voluntarily participated in this research and randomly divided into two 15 individual groups (first group: power exercise; second group: plyometric exercise; third group: mixed exercise (power and plyometric and forth group: control group. The day before the performing of the six weeks exercise program, dynamic balance of examined students measured by Star Excursion Balance test (SEBT. During the six weeks that exercise group did their special exercises, the control group was asked to keep their daily body exercises and their own exercise. The day after the exercise period finished, the dynamic balance of examined students measured. Descriptive statistics one variable variance analyzes and perspective Tukey test in meaning level α≤0/05 used for statistical analyze. The results showed that power exercise, plyometric and mixed, caused meaningful increasing of examined students success distance in all eight aspects of SEBT. According to the results of the research, the   use of mixed exercise, plyometric and power (specially mixed exercises is suggested in order to decrease the probability of injury and the improvement of athlete’s dynamic balance.  . Keywords: Power Exercise, Plyometric Exercise, Mixed Exercise, Dynamic Balance

  5. Tender frequency and market concentration in balancing power markets

    International Nuclear Information System (INIS)

    Knaut, Andreas; Obermueller, Frank; Weiser, Florian

    2017-01-01

    Balancing power markets ensure the short-term balance of supply and demand in electricity markets and their importance may increase with a higher share of fluctuating renewable electricity production. While it is clear that shorter tender frequencies, e.g. daily or hourly, are able to increase the efficiency compared to a weekly procurement, it remains unclear in which respect market concentration will be affected. Against this background, we develop a numerical electricity market model to quantify the possible effects of shorter tender frequencies on costs and market concentration. We find that shorter time spans of procurement are able to lower the costs by up to 15%. While market concentration decreases in many markets, we - surprisingly - identify cases in which shorter time spans lead to higher concentration.

  6. Tender frequency and market concentration in balancing power markets

    Energy Technology Data Exchange (ETDEWEB)

    Knaut, Andreas; Obermueller, Frank; Weiser, Florian

    2017-01-15

    Balancing power markets ensure the short-term balance of supply and demand in electricity markets and their importance may increase with a higher share of fluctuating renewable electricity production. While it is clear that shorter tender frequencies, e.g. daily or hourly, are able to increase the efficiency compared to a weekly procurement, it remains unclear in which respect market concentration will be affected. Against this background, we develop a numerical electricity market model to quantify the possible effects of shorter tender frequencies on costs and market concentration. We find that shorter time spans of procurement are able to lower the costs by up to 15%. While market concentration decreases in many markets, we - surprisingly - identify cases in which shorter time spans lead to higher concentration.

  7. When Do States Balance Power?

    DEFF Research Database (Denmark)

    Hariri, Jacob Gerner; Wivel, Anders

    2010-01-01

    This paper explores the logic of balancing in structural realist theory. Arguably, the durability of the unipolar moment is a challenge to the logic of balancing. The paper uses the tools of microeconomics to build a mathematical model of structural realism. The simple model reiterates...... the structural realist prediction that the weaker states should balance the unipole. Under a slight model extension, it is shown that efforts to balance in separate capabilities always tends to offset each other. Under this extension, the durability of the unipolar moment is in fact consistent...

  8. The European system and the Egyptian question 1827-1841 : a study in the theory of balance of power

    OpenAIRE

    Abd El Sattar El Badri, Mohammed

    1996-01-01

    Ankara : The Department of International Relations and Institute of Economics and Social Sciences, Bilkent Univ., 1996. Thesis (Ph.D.) -- Bilkent University, 1996. Includes bibliographical references leaves 289-295. This work aims at explaining the events of the Egyptian Question through the tools of balance of power theory. It is the main hypothesis of this work that the Egyptian Question affected the balance of power in Europe, i.e. Equilibrium, and therefore, was subjecte...

  9. Relationship of the functional movement screen in-line lunge to power, speed, and balance measures.

    Science.gov (United States)

    Hartigan, Erin H; Lawrence, Michael; Bisson, Brian M; Torgerson, Erik; Knight, Ryan C

    2014-05-01

    The in-line lunge of the Functional Movement Screen (FMS) evaluates lateral stability, balance, and movement asymmetries. Athletes who score poorly on the in-line lunge should avoid activities requiring power or speed until scores are improved, yet relationships between the in-line lunge scores and other measures of balance, power, and speed are unknown. (1) Lunge scores will correlate with center of pressure (COP), maximum jump height (MJH), and 36.6-meter sprint time and (2) there will be no differences between limbs on lunge scores, MJH, or COP. Descriptive laboratory study. Level 3. Thirty-seven healthy, active participants completed the first 3 tasks of the FMS (eg, deep squat, hurdle step, in-line lunge), unilateral drop jumps, and 36.6-meter sprints. A 3-dimensional motion analysis system captured MJH. Force platforms measured COP excursion. A laser timing system measured 36.6-m sprint time. Statistical analyses were used to determine whether a relationship existed between lunge scores and COP, MJH, and 36.6-m speed (Spearman rho tests) and whether differences existed between limbs in lunge scores (Wilcoxon signed-rank test), MJH, and COP (paired t tests). Lunge scores were not significantly correlated with COP, MJH, or 36.6-m sprint time. Lunge scores, COP excursion, and MJH were not statistically different between limbs. Performance on the FMS in-line lunge was not related to balance, power, or speed. Healthy participants were symmetrical in lunging measures and MJH. Scores on the FMS in-line lunge should not be attributed to power, speed, or balance performance without further examination. However, assessing limb symmetry appears to be clinically relevant.

  10. Effects of a Supervised versus an Unsupervised Combined Balance and Strength Training Program on Balance and Muscle Power in Healthy Older Adults: A Randomized Controlled Trial.

    Science.gov (United States)

    Lacroix, André; Kressig, Reto W; Muehlbauer, Thomas; Gschwind, Yves J; Pfenninger, Barbara; Bruegger, Othmar; Granacher, Urs

    2016-01-01

    Losses in lower extremity muscle strength/power, muscle mass and deficits in static and particularly dynamic balance due to aging are associated with impaired functional performance and an increased fall risk. It has been shown that the combination of balance and strength training (BST) mitigates these age-related deficits. However, it is unresolved whether supervised versus unsupervised BST is equally effective in improving muscle power and balance in older adults. This study examined the impact of a 12-week BST program followed by 12 weeks of detraining on measures of balance and muscle power in healthy older adults enrolled in supervised (SUP) or unsupervised (UNSUP) training. Sixty-six older adults (men: 25, women: 41; age 73 ± 4 years) were randomly assigned to a SUP group (2/week supervised training, 1/week unsupervised training; n = 22), an UNSUP group (3/week unsupervised training; n = 22) or a passive control group (CON; n = 22). Static (i.e., Romberg Test) and dynamic (i.e., 10-meter walk test) steady-state, proactive (i.e., Timed Up and Go Test, Functional Reach Test), and reactive balance (e.g., Push and Release Test), as well as lower extremity muscle power (i.e., Chair Stand Test; Stair Ascent and Descent Test) were tested before and after the active training phase as well as after detraining. Adherence rates to training were 92% for SUP and 97% for UNSUP. BST resulted in significant group × time interactions. Post hoc analyses showed, among others, significant training-related improvements for the Romberg Test, stride velocity, Timed Up and Go Test, and Chair Stand Test in favor of the SUP group. Following detraining, significantly enhanced performances (compared to baseline) were still present in 13 variables for the SUP group and in 10 variables for the UNSUP group. Twelve weeks of BST proved to be safe (no training-related injuries) and feasible (high attendance rates of >90%). Deficits of balance and lower extremity muscle power can be

  11. Ecological balance of power generation from sewage gas; Oekobilanz Klaergasverstromung

    Energy Technology Data Exchange (ETDEWEB)

    Ronchetti, C.; Bienz, P.; Pridal, R.

    2002-07-01

    This report for the Swiss Federal Office of Energy (SFOE) presents the ecological balance made for the production of electrical power from biogas that is produced in waste water treatment plants. The study was needed as the basis for deciding if power thus generated could be certified to the strict 'Naturemade Star' standards. This label is used to designate 'green' power. The report briefly describes the processes usually used in the treatment of sewage sludge, the energy-intensive aerobic and anaerobic digestion, which produces biogas. The ecological factors of the two processes were assessed using the Eco-Indicator 99 tool. The results are discussed, which showed that a typical modern waste water treatment plant is significantly better as far as energy is concerned than older examples of plant (e.g. those built in 1995) as far as ecological impact is concerned. Also, the study addresses other forms of biogas use, like, for example, its use as a fuel for vehicles.

  12. State-of-Charge Estimation and Active Cell Pack Balancing Design of Lithium Battery Power System for Smart Electric Vehicle

    OpenAIRE

    Gao, Z. C.; Chin, C. S.; Toh, W. D.; Chiew, J.; Jia, J.

    2017-01-01

    This paper presents an integrated state-of-charge (SOC) estimation model and active cell balancing of a 12-cell lithium iron phosphate (LiFePO4) battery power system. The strong tracking cubature extended Kalman filter (STCEKF) gave an accurate SOC prediction compared to other Kalman-based filter algorithms. The proposed groupwise balancing of the multiple SOC exhibited a higher balancing speed and lower balancing loss than other cell balancing designs. The experimental results demonstrated t...

  13. Sensitivity of sensor-based sit-to-stand peak power to the effects of training leg strength, leg power and balance in older adults

    NARCIS (Netherlands)

    Regterschot, G Ruben H; Folkersma, Marjanne; Zhang, Wei; Baldus, Heribert; Stevens, Martin; Zijlstra, Wiebren

    Increasing leg strength, leg power and overall balance can improve mobility and reduce fall risk. Sensor-based assessment of peak power during the sit-to-stand (STS) transfer may be useful for detecting changes in mobility and fall risk. Therefore, this study investigated whether sensor-based STS

  14. Enhancing the calculation accuracy of performance characteristics of power-generating units by correcting general measurands based on matching energy balances

    Science.gov (United States)

    Shchinnikov, P. A.; Safronov, A. V.

    2014-12-01

    General principles of a procedure for matching energy balances of thermal power plants (TPPs), whose use enhances the accuracy of information-measuring systems (IMSs) during calculations of performance characteristics (PCs), are stated. To do this, there is the possibility for changing values of measured and calculated variables within intervals determined by measurement errors and regulations. An example of matching energy balances of the thermal power plants with a T-180 turbine is made. The proposed procedure allows one to reduce the divergence of balance equations by 3-4 times. It is shown also that the equipment operation mode affects the profit deficiency. Dependences for the divergence of energy balances on the deviation of input parameters and calculated data for the fuel economy before and after matching energy balances are represented.

  15. Balancing of generators at wind power plants. Operational balancing in normal operation at wind power plants; Auswuchten von Generatoren auf Windkraftanlagen. Betriebsauswuchten im Normalbetrieb der Windkraftanlage

    Energy Technology Data Exchange (ETDEWEB)

    Franke, Dieter [IDF vibrodiagnose GmbH, Dresden (Germany); Schmidt, Gerrit [WSB Service GmbH (Germany)

    2010-07-01

    An increasing or suddenly arising unbalanced state in the generator of a wind power plant can be recognized by means of condition monitoring systems and regularly accomplished oscillation diagnoses. A strong unbalanced state results in a fast bearing wear, increases the risk of outage and reduces the profit. The risk of a further damage of the generator by means of a clearly increased vibration severity often is substantial. The counterbalancing takes place at the extended rotor at work benches in workshops. Among other things, the substantial cost is based on the expense of the disassembly and remounting of the generator. The total costs may amount several ten thousand Euro. As an alternative to balancing in the workshop, an operating balancing is recommended on the plant in order to reduce the costs. This was successfully realized by the engineer's office IDF vibrodiagnose GmbH (Dresden, Federal Republic of Germany) by the example of a Vestas V44 plant. The authors of the contribution under consideration describe the approach and advantages of an operating balancing. The main vibration stimulation at generators are described.

  16. Relationship of the Functional Movement Screen In-Line Lunge to Power, Speed, and Balance Measures

    Science.gov (United States)

    Hartigan, Erin H.; Lawrence, Michael; Bisson, Brian M.; Torgerson, Erik; Knight, Ryan C.

    2014-01-01

    Background: The in-line lunge of the Functional Movement Screen (FMS) evaluates lateral stability, balance, and movement asymmetries. Athletes who score poorly on the in-line lunge should avoid activities requiring power or speed until scores are improved, yet relationships between the in-line lunge scores and other measures of balance, power, and speed are unknown. Hypothesis: (1) Lunge scores will correlate with center of pressure (COP), maximum jump height (MJH), and 36.6-meter sprint time and (2) there will be no differences between limbs on lunge scores, MJH, or COP. Study Design: Descriptive laboratory study. Level of Evidence: Level 3. Methods: Thirty-seven healthy, active participants completed the first 3 tasks of the FMS (eg, deep squat, hurdle step, in-line lunge), unilateral drop jumps, and 36.6-meter sprints. A 3-dimensional motion analysis system captured MJH. Force platforms measured COP excursion. A laser timing system measured 36.6-m sprint time. Statistical analyses were used to determine whether a relationship existed between lunge scores and COP, MJH, and 36.6-m speed (Spearman rho tests) and whether differences existed between limbs in lunge scores (Wilcoxon signed-rank test), MJH, and COP (paired t tests). Results: Lunge scores were not significantly correlated with COP, MJH, or 36.6-m sprint time. Lunge scores, COP excursion, and MJH were not statistically different between limbs. Conclusion: Performance on the FMS in-line lunge was not related to balance, power, or speed. Healthy participants were symmetrical in lunging measures and MJH. Clinical Relevance: Scores on the FMS in-line lunge should not be attributed to power, speed, or balance performance without further examination. However, assessing limb symmetry appears to be clinically relevant. PMID:24790688

  17. Minimizing Wind Power Producer's Balancing Costs Using Electrochemical Energy Storage: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Miettinen, J.; Tikka, V.; Lassila, J.; Partanen, J.; Hodge, B. M.

    2014-08-01

    This paper examines how electrochemical energy storage can be used to decrease the balancing costs of a wind power producer in the Nordic market. Because electrochemical energy storage is developing in both technological and financial terms, a sensitivity analysis was carried out for the most important variables in the wind-storage hybrid system. The system was studied from a wind power producer's point of view. The main result is that there are no technical limitations to using storage for reducing the balancing costs. However, in terms of economic feasibility, installing hybrid wind-storage systems such as the one studied in this paper faces challenges in both the short and long terms.

  18. Implementation of Four-Phase Interleaved Balance Charger for Series-Connected Batteries with Power Factor Correction

    Science.gov (United States)

    Juan, Y. L.; Lee, Y. T.; Lee, Y. L.; Chen, L. L.; Huang, M. L.

    2017-11-01

    A four-phase interleaved balance charger for series-connected batteries with power factor correction is proposed in this dissertation. In the two phases of two buckboost converters, the rectified ac power is firstly converted to a dc link capacitor. In the other two phases of two flyback converters, the rectified ac power is directly converted to charge the corresponding batteries. Additionally, the energy on the leakage inductance of flyback converter is bypassed to the dc link capacitor. Then, a dual-output balance charging circuit is connected to the dc link to deliver the dc link power to charge two batteries in the series-connected batteries module. The constant-current/constant-voltage charging strategy is adopted. Finally, a prototype of the proposed charger with rated power 500 W is constructed. From the experimental results, the performance and validity of the proposed topology are verified. Compared to the conventional topology with passive RCD snubber, the efficiency of the proposed topology is improved about 3% and the voltage spike on the active switch is also reduced. The efficiency of the proposed charger is at least 83.6 % within the CC/CV charging progress.

  19. Using the power balance model to simulate cross-country skiing on varying terrain.

    Science.gov (United States)

    Moxnes, John F; Sandbakk, Oyvind; Hausken, Kjell

    2014-01-01

    The current study adapts the power balance model to simulate cross-country skiing on varying terrain. We assumed that the skier's locomotive power at a self-chosen pace is a function of speed, which is impacted by friction, incline, air drag, and mass. An elite male skier's position along the track during ski skating was simulated and compared with his experimental data. As input values in the model, air drag and friction were estimated from the literature based on the skier's mass, snow conditions, and speed. We regard the fit as good, since the difference in racing time between simulations and measurements was 2 seconds of the 815 seconds racing time, with acceptable fit both in uphill and downhill terrain. Using this model, we estimated the influence of changes in various factors such as air drag, friction, and body mass on performance. In conclusion, the power balance model with locomotive power as a function of speed was found to be a valid tool for analyzing performance in cross-country skiing.

  20. Impact of Balance Of System (BOS) costs on photovoltaic power systems

    Science.gov (United States)

    Hein, G. F.; Cusick, J. P.; Poley, W. A.

    1978-01-01

    The Department of Energy has developed a program to effect a large reduction in the price of photovoltaic modules, with significant progress already achieved toward the 1986 goal of 50 cents/watt (1975 dollars). Remaining elements of a P/V power system (structure, battery storage, regulation, control, and wiring) are also significant cost items. The costs of these remaining elements are commonly referred to as Balance-of-System (BOS) costs. The BOS costs are less well defined and documented than module costs. The Lewis Research Center (LeRC) in 1976/77 and with two village power experiments that will be installed in 1978. The costs were divided into five categories and analyzed. A regression analysis was performed to determine correlations of BOS Costs per peak watt, with power size for these photovoltaic systems. The statistical relationship may be used for flat-plate, DC systems ranging from 100 to 4,000 peak watts. A survey of suppliers was conducted for comparison with the predicted BOS cost relationship.

  1. The raw material and waste activity balance in the projected nuclear power of Russia

    International Nuclear Information System (INIS)

    Adamov, E.O.; Ganev, I.Kh.; Lopatkin, A.V.; Muratov, V.G.; Orlov, V.V.

    1997-01-01

    Under discussion is the management of long-lived high-level wastes in the nuclear energy sector of Russia, the development of which on a large scale in the next century is motivated by the need for arresting the increasing consumption of fossil fuels. The prerequisites for the nuclear power growth consists in the design of naturally safe reactors and development of a transmutational nuclear fuel cycle (NFC) technology. The choice of operations in such a cycle and of their quantitative characteristics, is aimed at minimizing the wastes to approach the radiation balance with the natural uranium extracted and put to use. The paper discusses the way the approximation to the balance between the raw material and waste activity is influenced by introduction of the transmutational NFC (in case 2), inclusion of transmutation reactors into the energy mix (case 1), partial disposal of actinide wastes into outer space, and by recycling of protactinium (case 3). It is shown that such a balance can be sustained for a considerable time in cases 2 and 3 or throughout the operation stage of the future nuclear power (case 1). (orig.)

  2. Does a Relationship Exist Between Lower Body Power and Balance Scores Among Older Adults?

    Science.gov (United States)

    Shim, Andrew; Harr, Brady; Waller, Mike

    2018-03-12

    Falls are the second-leading cause of unintentional injury and death worldwide. To determine if a relationship exists between lower body power scores and center of pressure (CoP) and limits of stability (LoS) scores. A one-shot case study design (n = 13) was selected for the investigation. All participants were assessed stability scores via computerized posturography to determine CoP and LoS balance scores. Participants stood on a perturbed surface with their eyes open and closed. An experimental stair ramp with a switch mat timing device was used to determine lower body power scores in watts. There was a strong correlation (r = 0.725, p = 0.005) between the posterior (LoS) plane and relative peak power. An intraclass R revealed a strong correlation among the three trials (R = 0.831) performed on the stair ramp. Muscle power output and LoS scores have moderate to strong correlations with balance scores in older adults.

  3. Short-term Power Load Forecasting Based on Balanced KNN

    Science.gov (United States)

    Lv, Xianlong; Cheng, Xingong; YanShuang; Tang, Yan-mei

    2018-03-01

    To improve the accuracy of load forecasting, a short-term load forecasting model based on balanced KNN algorithm is proposed; According to the load characteristics, the historical data of massive power load are divided into scenes by the K-means algorithm; In view of unbalanced load scenes, the balanced KNN algorithm is proposed to classify the scene accurately; The local weighted linear regression algorithm is used to fitting and predict the load; Adopting the Apache Hadoop programming framework of cloud computing, the proposed algorithm model is parallelized and improved to enhance its ability of dealing with massive and high-dimension data. The analysis of the household electricity consumption data for a residential district is done by 23-nodes cloud computing cluster, and experimental results show that the load forecasting accuracy and execution time by the proposed model are the better than those of traditional forecasting algorithm.

  4. Joint Load Balancing and Power Allocation for Hybrid VLC/RF Networks

    KAUST Repository

    Obeed, Mohanad

    2018-01-15

    In this paper, we propose and study a new joint load balancing (LB) and power allocation (PA) scheme for a hybrid visible light communication (VLC) and radio frequency (RF) system consisting of one RF\\\\access point (AP) and multiple VLC\\\\APs. An iterative algorithm is proposed to distribute the users on the APs and distribute the powers of these APs on their users. In PA subproblem, an optimization problem is formulated to allocate the power of each AP to the connected users for the total achievable data rates maximization. It is proved that the PA optimization problem is concave but not easy to tackle. Therefore, we provide a new algorithm to obtain the optimal dual variables after formulating them in terms of each other. Then, the users that are connected to the overloaded APs and receive less data rates start seeking for other APs that offer higher data rates. Users with lower data rates continue re-connecting from AP to other to balance the load only if this travel increases the summation of the achievable data rates and enhances the system fairness. The numerical results demonstrate that the proposed algorithms improve the system capacity and system fairness with fast convergence.

  5. Joint Load Balancing and Power Allocation for Hybrid VLC/RF Networks

    KAUST Repository

    Obeed, Mohanad; Salhab, Anas M.; Zummo, Salam A.; Alouini, Mohamed-Slim

    2018-01-01

    In this paper, we propose and study a new joint load balancing (LB) and power allocation (PA) scheme for a hybrid visible light communication (VLC) and radio frequency (RF) system consisting of one RF\\access point (AP) and multiple VLC\\APs. An iterative algorithm is proposed to distribute the users on the APs and distribute the powers of these APs on their users. In PA subproblem, an optimization problem is formulated to allocate the power of each AP to the connected users for the total achievable data rates maximization. It is proved that the PA optimization problem is concave but not easy to tackle. Therefore, we provide a new algorithm to obtain the optimal dual variables after formulating them in terms of each other. Then, the users that are connected to the overloaded APs and receive less data rates start seeking for other APs that offer higher data rates. Users with lower data rates continue re-connecting from AP to other to balance the load only if this travel increases the summation of the achievable data rates and enhances the system fairness. The numerical results demonstrate that the proposed algorithms improve the system capacity and system fairness with fast convergence.

  6. Assessing harmonic current source modelling and power definitions in balanced and unbalanced networks

    Energy Technology Data Exchange (ETDEWEB)

    Atkinson-Hope, Gary; Stemmet, W.C. [Cape Peninsula University of Technology, Cape Town Campus, Cape Town (South Africa)

    2006-07-01

    The purpose of this paper is to assess the DlgSILENT PowerFactory software power definitions (indices) in terms of phase and sequence components for balanced and unbalanced networks when harmonic distortion is present and to compare its results to hand calculations done, following recommendation made by the IEEE Working Group on this topic. This paper also includes the development of a flowchart for calculating power indices in balanced and unbalanced three-phase networks when non-sinusoidal voltages and currents are present. A further purpose is to determine how two industrial grade harmonic analysis software packages (DlgSILENT and ERACS) model three-phase harmonic sources used for current penetration studies and to compare their results when applied to a network. From the investigations, another objective was to develop a methodology for modelling harmonic current sources based on a spectrum obtained from measurements. Three case studies were conducted and the assessment and developed methodologies were shown to be effective. (Author)

  7. Power cycle heat balance software for personal computer (PC)2TM

    International Nuclear Information System (INIS)

    Bockh, P. von; Rodriguez, H.

    1996-01-01

    This paper describes the PC-based power cycle balance of plant software (PC)trademark (Power Cycle on Personal Computer). It is designed to assist nuclear, fossil, and industrial power plants so that steam cycles can be simulated, analyzed and optimized. First, the cycle model is developed on the screen. The elements of the power cycle are taken from a tool box containing all components of a modern power cycle. The elements are connected by using a mouse. The next step is the input of the design values of the components or data taken from performance tests. This entire input sequence is guided by the program. Based on the input data, the physical behavior of each component is simulated according to established physical rules. Part load operation or other off-design conditions can be calculated. The program is designed for use by power plant engineers and power engineering firms to optimize new power cycles, perform problem-solving analyses, optimize component retrofit, and train power plant engineers and operators. It also can be used by universities to educate engineering students

  8. Theoretical and perceived balance of power inside Spanish public hospitals.

    Science.gov (United States)

    Salvadores, P; Schneider, J; Zubero, I

    2001-01-01

    The hierarchical pyramid inside Spanish public hospitals was radically changed by the Health Reform Law promulgated in 1986. According to it, the manpower of the hospitals was divided into three divisions (Medical, Nursing, General Services/Administration), which from then on occupied the same level, only subject to the general manager. Ten years after the implementation of the law, the present study was designed in order to investigate if the legal changes had indeed produced a real change in the balance of power inside the hospitals, as perceived by the different workers within them. A questionnaire was administered to 1,027 workers from four different public hospitals (two university-based and two district hospitals). The participants belonged to all divisions, and to all three operative levels (staff, supervisory and managerial) within them. The questionnaire inquired about the perceived power inside each division and hierarchical level, as well as about that of the other divisions and hierarchical levels. Every division attributed the least power to itself. The Nursing and the Administrative division attributed the highest power to the physicians, and these attributed the highest power to the General Services/Administrative division. All hierarchical levels (including the formal top of the pyramid) attributed significantly more power to the other than to them. More than ten years after the implementation of the new law, the majority of workers still perceive that the real power within the hospitals is held by the physicians (whereas these feel that it has shifted to the administrators). No division or hierarchical level believes it holds any significant degree of power, and this carries with it the danger of also not accepting any responsibility.

  9. State-of-Charge Estimation and Active Cell Pack Balancing Design of Lithium Battery Power System for Smart Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Z. C. Gao

    2017-01-01

    Full Text Available This paper presents an integrated state-of-charge (SOC estimation model and active cell balancing of a 12-cell lithium iron phosphate (LiFePO4 battery power system. The strong tracking cubature extended Kalman filter (STCEKF gave an accurate SOC prediction compared to other Kalman-based filter algorithms. The proposed groupwise balancing of the multiple SOC exhibited a higher balancing speed and lower balancing loss than other cell balancing designs. The experimental results demonstrated the robustness and performance of the battery when subjected to current load profile of an electric vehicle under varying ambient temperature.

  10. Radiation losses and global power balance of JT-60 plasmas

    International Nuclear Information System (INIS)

    Nishitani, T.; Itami, K.; Nagashima, K.; Tsuji, S.; Hosogane, N.; Yoshida, H.; Ando, T.; Kubo, H.; Takeuchi, H.

    1990-01-01

    The radiation losses and the global power balance for Ohmic and neutral beam heated plasmas have been investigated in different JT-60 configurations. Discharges with a TiC coated molybdenum wall and with a graphite wall, with limiter, outer and lower X-point configurations have been studied by bolometric measurements, thermocouples and an infrared TV camera. In neutral beam heated outer X-point discharges with a TiC coated molybdenum first wall, the radiation loss of the main plasma was very low (10% of the absorbed power). The radiation loss due to oxygen was dominant in this case. On the contrary, in discharges with TiC coated molybdenum limiters the radiation loss was very high (>60% of the absorbed power). In the discharges with a graphite wall the radiated power from the main plasma was 20-25% for both limiter and lower X-point configurations. In lower X-point discharges the main contributor to the radiation loss was oxygen, whereas in limiter discharges the loss due to carbon was equal to the loss due to oxygen. The radiation loss from the lower X-point divertor increased with increasing electron density of the main plasma. (author). 33 refs, 14 figs, 1 tab

  11. Japan and the changing global balance of power: The view from the summit

    OpenAIRE

    Dobson, H.

    2010-01-01

    This article explores Japan's relative decline and its responses to the changing global balance of power through a case study of one symptom of this shift: the rise of the G20 as the 'premier forum for international economic co-operation' at the expense of the G8. The G8 has traditionally held a significant position in Japan's international relations that appears to be undermined by the rise of the G20. Japan's responses to these developments reveal it to be a status quo power that is still c...

  12. Modeling a power-to-renewable methane system for an assessment of power grid balancing options in the Baltic States’ region

    International Nuclear Information System (INIS)

    Zoss, Toms; Dace, Elina; Blumberga, Dagnija

    2016-01-01

    Highlights: • A mathematical modeling framework developed for assessing power-to-methane systems. • An integrated system of wind power, electrolysis, biogas and methanation assessed. • Power system is more stable with methanizing biogas with H_2 from excess wind power. • Accumulation of H_2 limits production of renewable methane. • Large potential for wind power development in the Baltic States. - Abstract: The explicit tendency to increase the power generation from stochastic renewable resources forces to look for technological solutions of energy management and storage. In the recent years, the concept of power-to-gas, where the excess energy is converted into hydrogen and/or further methanized into renewable methane, is gaining high popularity among researchers. In this study, we assess the power-to-renewable methane system as the potential technology for power grid balancing. For the assessment, a mathematical model has been developed that assists in understanding of whether a power-to-renewable methane system can be developed in a region with specific installed and planned capacities of wind energy and biogas plants. Considering the varying amount of excess power available for H_2 production and the varying biogas quality, the aim of the model is to simulate the system to determine, if wind power generation meets the needs of biogas plants for storing the excess energy in the form of methane via the methanation process. For the case study, the Baltic States (Estonia, Latvia, and Lithuania) have been selected, as the region is characterized by high dependence on fossil energy sources and electricity import. The results show that with the wind power produced in the region it would be possible to increase the average CH_4 content in the methanized biogas by up to 48.4%. Yet, even with a positive H_2 net production rate, not in all cases the maximum possible quality of the renewable methane would be achieved, as at moments the necessary amount of H_2 for

  13. Reliability and relationships among handgrip strength, leg extensor strength and power, and balance in older men.

    Science.gov (United States)

    Jenkins, Nathaniel D M; Buckner, Samuel L; Bergstrom, Haley C; Cochrane, Kristen C; Goldsmith, Jacob A; Housh, Terry J; Johnson, Glen O; Schmidt, Richard J; Cramer, Joel T

    2014-10-01

    To quantify the reliability of isometric leg extension torque (LEMVC), rate of torque development (LERTD), isometric handgrip force (HGMVC) and RFD (HGRFD), isokinetic leg extension torque and power at 1.05rad·s(-1) and 3.14rad·s(-1); and explore relationships among strength, power, and balance in older men. Sixteen older men completed 3 isometric handgrips, 3 isometric leg extensions, and 3 isokinetic leg extensions at 1.05rad·s(-1) and 3.14rad·s(-1) during two visits. Intraclass correlation coefficients (ICCs), ICC confidence intervals (95% CI), coefficients of variation (CVs), and Pearson correlation coefficients were calculated. LERTD demonstrated no reliability. The CVs for LERTD and HGRFD were ≤23.26%. HGMVC wasn't related to leg extension torque or power, or balance (r=0.14-0.47; p>0.05). However, moderate to strong relationships were found among isokinetic leg extension torque at 1.05rad·s(-1) and 3.14rad·s(-1), leg extension mean power at 1.05rad·s(-1), and functional reach (r=0.51-0.95; p≤0.05). LERTD and HGRFD weren't reliable and shouldn't be used as outcome variables in older men. Handgrip strength may not be an appropriate surrogate for lower body strength, power, or balance. Instead, perhaps handgrip strength should only be used to describe upper body strength or functionality, which may compliment isokinetic assessments of lower body strength, which were reliable and related to balance. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Balancing Europe's wind power output through spatial deployment informed by weather regimes.

    Science.gov (United States)

    Grams, Christian M; Beerli, Remo; Pfenninger, Stefan; Staffell, Iain; Wernli, Heini

    2017-08-01

    As wind and solar power provide a growing share of Europe's electricity1, understanding and accommodating their variability on multiple timescales remains a critical problem. On weekly timescales, variability is related to long-lasting weather conditions, called weather regimes2-5, which can cause lulls with a loss of wind power across neighbouring countries6. Here we show that weather regimes provide a meteorological explanation for multi-day fluctuations in Europe's wind power and can help guide new deployment pathways which minimise this variability. Mean generation during different regimes currently ranges from 22 GW to 44 GW and is expected to triple by 2030 with current planning strategies. However, balancing future wind capacity across regions with contrasting inter-regime behaviour - specifically deploying in the Balkans instead of the North Sea - would almost eliminate these output variations, maintain mean generation, and increase fleet-wide minimum output. Solar photovoltaics could balance low-wind regimes locally, but only by expanding current capacity tenfold. New deployment strategies based on an understanding of continent-scale wind patterns and pan-European collaboration could enable a high share of wind energy whilst minimising the negative impacts of output variability.

  15. Study of regeneration system of 300 MW power unit based on nondeaerating heat balance diagram at reduced load

    Science.gov (United States)

    Esin, S. B.; Trifonov, N. N.; Sukhorukov, Yu. G.; Yurchenko, A. Yu.; Grigor'eva, E. B.; Snegin, I. P.; Zhivykh, D. A.; Medvedkin, A. V.; Ryabich, V. A.

    2015-09-01

    More than 30 power units of thermal power stations, based on the nondeaerating heat balance diagram, successfully operate in the former Soviet Union. Most of them are power units with a power of 300 MW, equipped with HTGZ and LMZ turbines. They operate according to a variable electric load curve characterized by deep reductions when undergoing night minimums. Additional extension of the range of power unit adjustment makes it possible to maintain the dispatch load curve and obtain profit for the electric power plant. The objective of this research is to carry out estimated and experimental processing of the operating regimes of the regeneration system of steam-turbine plants within the extended adjustment range and under the conditions when the constraints on the regeneration system and its equipment are removed. Constraints concerning the heat balance diagram that reduce the power unit efficiency when extending the adjustment range have been considered. Test results are presented for the nondeaerating heat balance diagram with the HTGZ turbine. Turbine pump and feed electric pump operation was studied at a power unit load of 120-300 MW. The reliability of feed pump operation is confirmed by a stable vibratory condition and the absence of cavitation noise and vibration at a frequency that characterizes the cavitation condition, as well as by oil temperature maintenance after bearings within normal limits. Cavitation performance of pumps in the studied range of their operation has been determined. Technical solutions are proposed on providing a profitable and stable operation of regeneration systems when extending the range of adjustment of power unit load. A nondeaerating diagram of high-pressure preheater (HPP) condensate discharge to the mixer. A regeneration system has been developed and studied on the operating power unit fitted with a deaeratorless thermal circuit of the system for removing the high-pressure preheater heating steam condensate to the mixer

  16. Computerized heat balance models to predict performance of operating nuclear power plants

    International Nuclear Information System (INIS)

    Breeding, C.L.; Carter, J.C.; Schaefer, R.C.

    1983-01-01

    The use of computerized heat balance models has greatly enhanced the decision making ability of TVA's Division of Nuclear Power. These models are utilized to predict the effects of various operating modes and to analyze changes in plant performance resulting from turbine cycle equipment modifications with greater speed and accuracy than was possible before. Computer models have been successfully used to optimize plant output by predicting the effects of abnormal condenser circulating water conditions. They were utilized to predict the degradation in performance resulting from installation of a baffle plate assembly to replace damaged low-pressure blading, thereby providing timely information allowing an optimal economic judgement as to when to replace the blading. Future use will be for routine performance test analysis. This paper presents the benefits of utility use of computerized heat balance models

  17. Power Balancing of Inline Multicylinder Diesel Engine

    Directory of Open Access Journals (Sweden)

    S. H. Gawande

    2012-01-01

    Full Text Available In this work, a simplified methodology is presented for power balancing by reducing the amplitude of engine speed variation, which result in excessive torsional vibrations of the crankshaft of inline six-cylinder diesel engine. In modern fuel injection systems for reciprocating engines, nonuniform cylinder-wise torque contribution is a common problem due to nonuniform fuel supply due to a defect in fuel injection system, causing increased torsional vibration levels of the crankshaft and stress of mechanical parts. In this paper, a mathematical model for the required fuel adjustment by using amplitude of engine speed variation applied on the flywheel based on engine dynamics is suggested. From the found empirical relations and FFT analysis, the amplitude of engine speed variation (i.e., torsional vibration levels of the crankshaft of inline six-cylinder diesel engine genset can be reduced up to 55%. This proposed methodology is simulated by developing MATALB code for uniform and nonuniform working of direct injection diesel engine of SL90 type manufactured by Kirloskar Oil Engine Ltd., Pune, India.

  18. Lifetime and economic analyses of lithium-ion batteries for balancing wind power forecast error

    DEFF Research Database (Denmark)

    Swierczynski, Maciej Jozef; Stroe, Daniel Ioan; Stroe, Ana-Irina

    2015-01-01

    is considered. In this paper, the economic feasibility of lithium-ion batteries for balancing the wind power forecast error is analysed. In order to perform a reliable assessment, an ageing model of lithium-ion battery was developed considering both cycling and calendar life. The economic analysis considers two......, it was found that for total elimination of the wind power forecast error, it is required to have a 25-MWh Li-ion battery energy storage system for the considered 2 MW WT....

  19. A ten year perspective on power balances and CO2 emissions in Northern Europe

    International Nuclear Information System (INIS)

    Tennbakk, Berit; Torgersen, Lasse

    2003-10-01

    The electric power balance and electricity trade will change a lot in Northern Europe over the next decade. Independent of the price of emission quotas, the balance will worsen, especially for Sweden and Germany, but the absolute numbers are strongly dependent on the demand growth. New production capacity will be built primarily in the Netherlands and Norway. Finland will also have a growing need of imported power until the new nuclear power plant is running, around 2012. Denmark will remain a net exporter. If the construction of new generating capacity is slowed down by economic or administrative reasons, the raising prices will lead to higher production in the Nordic coal fired plants. The CO 2 emissions will increase and the Nordic countries will become net importers of emission quotas, even at a quota price of 20 Euros per ton CO 2 , since new natural gas plants in Norway and Netherlands will outperform existing coal plants in Poland and Germany at high quota prices

  20. Normative data and the influence of age and gender on power, balance, flexibility, and functional movement in healthy service members.

    Science.gov (United States)

    Teyhen, Deydre S; Riebel, Mark A; McArthur, Derrick R; Savini, Matthew; Jones, Mackenzie J; Goffar, Stephen L; Kiesel, Kyle B; Plisky, Phillip J

    2014-04-01

    Determine the influence of age and sex and describe normative data on field expedient tests associated with power, balance, trunk stability, mobility, and functional movement in a military population. Participants (n = 247) completed a series of clinical and functional tests, including closed-chain ankle dorsiflexion (DF), Functional Movement Screen (FMS), Y-Balance Test Lower Quarter (YBT-LQ), Y-Balance Test Upper Quarter (YBT-UQ), single leg vertical jump (SLVJ), 6-m timed hop (6-m timed), and triple hop. Descriptive statistics were calculated. Analysis of variance tests were performed to compare the results based on sex and age (30 years). Service members demonstrated DF of 34.2 ± 6.1°, FMS composite score of 16.2 ± 2.2, YBT-LQ normalized composite score of 96.9 ± 8.6%, YBT-UQ normalized composite score of 87.6 ± 9.6%, SLVJ of 26.9 ± 8.6 cm, 6-m hop of 2.4 ± 0.5 seconds, and a triple hop of 390.9 ± 110.8 cm. Men performed greater than women (p power, balance, and trunk stability tests, whereas younger individuals performed better on power, balance, mobility, and functional movement. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

  1. LDMOS Channel Thermometer Based on a Thermal Resistance Sensor for Balancing Temperature in Monolithic Power ICs

    Directory of Open Access Journals (Sweden)

    Tingyou Lin

    2017-06-01

    Full Text Available This paper presents a method of thermal balancing for monolithic power integrated circuits (ICs. An on-chip temperature monitoring sensor that consists of a poly resistor strip in each of multiple parallel MOSFET banks is developed. A temperature-to-frequency converter (TFC is proposed to quantize on-chip temperature. A pulse-width-modulation (PWM methodology is developed to balance the channel temperature based on the quantization. The modulated PWM pulses control the hottest of metal-oxide-semiconductor field-effect transistor (MOSFET bank to reduce its power dissipation and heat generation. A test chip with eight parallel MOSFET banks is fabricated in TSMC 0.25 μm HV BCD processes, and total area is 900 × 914 μm2. The maximal temperature variation among the eight banks can reduce to 2.8 °C by the proposed thermal balancing system from 9.5 °C with 1.5 W dissipation. As a result, our proposed system improves the lifetime of a power MOSFET by 20%.

  2. Single-Phase Single-Stage Grid Tied Solar PV System with Active Power Filtering Using Power Balance Theory

    Science.gov (United States)

    Singh, Yashi; Hussain, Ikhlaq; Singh, Bhim; Mishra, Sukumar

    2018-03-01

    In this paper, power quality features such as harmonics mitigation, power factor correction with active power filtering are addressed in a single-stage, single-phase solar photovoltaic (PV) grid tied system. The Power Balance Theory (PBT) with perturb and observe based maximum power point tracking algorithm is proposed for the mitigation of power quality problems in a solar PV grid tied system. The solar PV array is interfaced to a single phase AC grid through a Voltage Source Converter (VSC), which provides active power flow from a solar PV array to the grid as well as to the load and it performs harmonics mitigation using PBT based control. The solar PV array power varies with sunlight and due to this, the solar PV grid tied VSC works only 8-10 h per day. At night, when PV power is zero, the VSC works as an active power filter for power quality improvement, and the load active power is delivered by the grid to the load connected at the point of common coupling. This increases the effective utilization of a VSC. The system is modelled and simulated using MATLAB and simulated responses of the system at nonlinear loads and varying environmental conditions are also validated experimentally on a prototype developed in the laboratory.

  3. Accounting of the Power Balance for Neutral-beam heated H-Mode Plasmas in NSTX

    International Nuclear Information System (INIS)

    Paul, S.F.; Maingi, R.; Soukhanovskii, V.; Kaye, S.M.; Kugel, H.

    2004-01-01

    A survey of the dependence of power balance on input power, shape, and plasma current was conducted for neutral-beam-heated plasmas in the National Spherical Torus Experiment (NSTX). Measurements of heat to the divertor strike plates and divertor and core radiation were taken over a wide range of plasma conditions. The different conditions were obtained by inducing a L-mode to H-mode transition, changing the divertor configuration [lower single null (LSN) vs. double-null (DND)] and conducting a NBI power scan in H-mode. 60-70% of the net input power is accounted for in the LSN discharges with 20% of power lost as fast ions, 30-45% incident on the divertor plates, up to 10% radiated in the core, and about 12% radiated in the divertor. In contrast, the power accountability in DND is 85-90%. A comparison of DND and LSN data show that the remaining power in the LSN is likely to be directed to the upper divertor

  4. Low complexity transmit antenna selection with power balancing in OFDM systems

    KAUST Repository

    Park, Kihong

    2010-10-01

    In this paper, we consider multi-carrier systems with multiple transmit antennas under the power balancing constraint, which is defined as the constraint that the power on each antenna should be limited under a certain level due to the linearity of the power amplifier of the RF chain. Applying transmit antenna selection and fixed-power variable-rate transmission per subcarrier as a function of channel variations, we propose an implementation-friendly antenna selection method which offers a reduced complexity in comparison with the optimal antenna selection scheme. More specifically, in order to solve the subcarrier imbalance across the antennas, we operate a two-step reallocation procedure to minimize the loss of spectral efficiency. We also provide an analytic lower bound on the spectral efficiency for the proposed scheme. From selected numerical results, we show that our suboptimal scheme offers almost the same spectral efficiency as the optimal one. © 2010 IEEE.

  5. Using the power balance model to simulate cross-country skiing on varying terrain

    Directory of Open Access Journals (Sweden)

    Moxnes JF

    2014-05-01

    Full Text Available John F Moxnes,1 Øyvind Sandbakk,2 Kjell Hausken31Department for Protection, Norwegian Defence Research Establishment, Kjeller, Norway; 2Center for Elite Sports Research, Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway; 3Faculty of Social Sciences, University of Stavanger, Stavanger, NorwayAbstract: The current study adapts the power balance model to simulate cross-country skiing on varying terrain. We assumed that the skier’s locomotive power at a self-chosen pace is a function of speed, which is impacted by friction, incline, air drag, and mass. An elite male skier’s position along the track during ski skating was simulated and compared with his experimental data. As input values in the model, air drag and friction were estimated from the literature based on the skier's mass, snow conditions, and speed. We regard the fit as good, since the difference in racing time between simulations and measurements was 2 seconds of the 815 seconds racing time, with acceptable fit both in uphill and downhill terrain. Using this model, we estimated the influence of changes in various factors such as air drag, friction, and body mass on performance. In conclusion, the power balance model with locomotive power as a function of speed was found to be a valid tool for analyzing performance in cross-country skiing.Keywords: air drag, efficiency, friction coefficient, speed, locomotive power

  6. Balancing corporate power: a new Federalist paper.

    Science.gov (United States)

    Handy, C

    1992-01-01

    In an effort to govern their increasingly complex organizations, chief executives in some of today's largest corporations are turning to one of the world's oldest political philosophies-federalism. Given that organizations are seen more and more as minisocieties, the prospect of applying political principles to management makes a great deal of sense. Federalism is particularly appropriate because it offers a well-recognized system for dealing with paradoxes of power and control: the need to make things big by keeping them small; to encourage autonomy but within bounds; and to combine variety and shared purpose, individuality and partnership, local and global. As London Business School professor Charles Handy explains it, federalism responds to these paradoxes by balancing power among those in the center of the organization, those in the centers of expertise, and those in the center of the action--the operating businesses. The centers of federal organizations meet regularly, but they do not need to live together. Doing so would concentrate too much power in one place, whereas federalism gets its strength and energy from spreading responsibility across many decision points. Guided by five principles, federalism avoids the risks of autocracy and the overcontrol of a central bureaucracy. It ensures a measure of democracy and creates a "dispersed center" that is more a network than a place. That's why Asea Brown Boveri CEO Percy Barnevik calls his sprawling "multi-domestic" enterprise of 1,100 separate companies and 210,000 employees a federation. It succeeds because the independent bits, be they individuals, clusters, or business units, know they are part of the greater whole.

  7. Coverage extension and balancing the transmitted power of the moving relay node at LTE-A cellular network.

    Science.gov (United States)

    Aldhaibani, Jaafar A; Yahya, Abid; Ahmad, R Badlishah

    2014-01-01

    The poor capacity at cell boundaries is not enough to meet the growing demand and stringent design which required high capacity and throughput irrespective of user's location in the cellular network. In this paper, we propose new schemes for an optimum fixed relay node (RN) placement in LTE-A cellular network to enhance throughput and coverage extension at cell edge region. The proposed approach mitigates interferences between all nodes and ensures optimum utilization with the optimization of transmitted power. Moreover, we proposed a new algorithm to balance the transmitted power of moving relay node (MR) over cell size and providing required SNR and throughput at the users inside vehicle along with reducing the transmitted power consumption by MR. The numerical analysis along with the simulation results indicates that an improvement in capacity for users is 40% increment at downlink transmission from cell capacity. Furthermore, the results revealed that there is saving nearly 75% from transmitted power in MR after using proposed balancing algorithm. ATDI simulator was used to verify the numerical results, which deals with real digital cartographic and standard formats for terrain.

  8. Local and global particle and power balance in large area capacitive discharges

    International Nuclear Information System (INIS)

    Cho, Suwon; Lieberman, M A

    2003-01-01

    Large area radio frequency (rf) capacitive discharges have attracted recent interest for materials etching and deposition on large area substrates. A distinguishing feature is that the radial distribution of the absorbed rf power in these discharges depends on the rf voltage across the plates, independent of the radial variation of the plasma density n(r). A reduced set of steady-state fluid equations has been used to investigate the radial variation of n and electron temperature T e . The derived equations are shown to be invariant with respect to pL and pR, where p is the pressure, L is the plate separation and R is the discharge radius, and can be further reduced to the equations of the usual global balance model when R ε , the energy relaxation length. In this limit, the ionization frequency and T e are essentially independent of radius and n can be approximately described by the usual radial profile of a zeroth-order Bessel function. When R≥λ ε , n and T e are predominantly determined by local particle and power balance, and the n and T e radial profiles are flat over most of the volume except near the radial boundary, where n falls and T e rises to account for the increased losses at the boundary. The scale length of the edge density variation in the local balance regime is shown to be proportional to the energy relaxation length

  9. The effects of strength and power training on single-step balance recovery in older adults: a preliminary study.

    Science.gov (United States)

    Pamukoff, Derek N; Haakonssen, Eric C; Zaccaria, Joseph A; Madigan, Michael L; Miller, Michael E; Marsh, Anthony P

    2014-01-01

    Improving muscle strength and power may mitigate the effects of sarcopenia, but it is unknown if this improves an older adult's ability to recover from a large postural perturbation. Forward tripping is prevalent in older adults and lateral falls are important due to risk of hip fracture. We used a forward and a lateral single-step balance recovery task to examine the effects of strength training (ST) or power (PT) training on single-step balance recovery in older adults. Twenty older adults (70.8±4.4 years, eleven male) were randomly assigned to either a 6-week (three times/week) lower extremity ST or PT intervention. Maximum forward (FLean(max)) and lateral (LLean(max)) lean angle and strength and power in knee extension and leg press were assessed at baseline and follow-up. Fifteen participants completed the study (ST =7, PT =8). Least squares means (95% CI) for ΔFLean(max) (ST: +4.1° [0.7, 7.5]; PT: +0.6° [-2.5, 3.8]) and ΔLLean(max) (ST: +2.2° [0.4, 4.1]; PT: +2.6° [0.9, 4.4]) indicated no differences between groups following training. In exploratory post hoc analyses collapsed by group, ΔFLean(max) was +2.4° (0.1, 4.7) and ΔLLean(max) was +2.4° (1.2, 3.6). These improvements on the balance recovery tasks ranged from ~15%-30%. The results of this preliminary study suggest that resistance training may improve balance recovery performance, and that, in this small sample, PT did not lead to larger improvements in single-step balance recovery compared to ST.

  10. Loss of balance during balance beam walking elicits a multifocal theta band electrocortical response.

    Science.gov (United States)

    Sipp, Amy R; Gwin, Joseph T; Makeig, Scott; Ferris, Daniel P

    2013-11-01

    Determining the neural correlates of loss of balance during walking could lead to improved clinical assessment and treatment for individuals predisposed to falls. We used high-density electroencephalography (EEG) combined with independent component analysis (ICA) to study loss of balance during human walking. We examined 26 healthy young subjects performing heel-to-toe walking on a treadmill-mounted balance beam as well as walking on the treadmill belt (both at 0.22 m/s). ICA identified clusters of electrocortical EEG sources located in or near anterior cingulate, anterior parietal, superior dorsolateral-prefrontal, and medial sensorimotor cortex that exhibited significantly larger mean spectral power in the theta band (4-7 Hz) during walking on the balance beam compared with treadmill walking. Left and right sensorimotor cortex clusters produced significantly less power in the beta band (12-30 Hz) during walking on the balance beam compared with treadmill walking. For each source cluster, we also computed a normalized mean time/frequency spectrogram time locked to the gait cycle during loss of balance (i.e., when subjects stepped off the balance beam). All clusters except the medial sensorimotor cluster exhibited a transient increase in theta band power during loss of balance. Cluster spectrograms demonstrated that the first electrocortical indication of impending loss of balance occurred in the left sensorimotor cortex at the transition from single support to double support prior to stepping off the beam. These findings provide new insight into the neural correlates of walking balance control and could aid future studies on elderly individuals and others with balance impairments.

  11. Poor anaerobic power/capability and static balance predicted prospective musculoskeletal injuries among Soldiers of the 101st Airborne (Air Assault) Division.

    Science.gov (United States)

    Nagai, Takashi; Lovalekar, Mita; Wohleber, Meleesa F; Perlsweig, Katherine A; Wirt, Michael D; Beals, Kim

    2017-11-01

    Musculoskeletal injuries have negatively impacted tactical readiness. The identification of prospective and modifiable risk factors of preventable musculoskeletal injuries can guide specific injury prevention strategies for Soldiers and health care providers. To analyze physiological and neuromuscular characteristics as predictors of preventable musculoskeletal injuries. Prospective-cohort study. A total of 491 Soldiers were enrolled and participated in the baseline laboratory testing, including body composition, aerobic capacity, anaerobic power/capacity, muscular strength, flexibility, static balance, and landing biomechanics. After reviewing their medical charts, 275 male Soldiers who met the criteria were divided into two groups: with injuries (INJ) and no injuries (NOI). Simple and multiple logistic regression analyses were used to calculate the odds ratio (OR) and significant predictors of musculoskeletal injuries (pmodel included the static balance with eyes-closed and peak anaerobic power as predictors of future injuries (p<0.001). The current results highlighted the importance of anaerobic power/capacity and static balance. High intensity training and balance exercise should be incorporated in their physical training as countermeasures. Copyright © 2017 Sports Medicine Australia. All rights reserved.

  12. Wind Turbines and Heat Pumps. Balancing wind power fluctuations using flexible demand

    International Nuclear Information System (INIS)

    Warmer, C.J.; Hommelberg, M.P.F.; Kamphuis, I.G.; Derszi, Z.; Kok, J.K.

    2007-01-01

    In order to overcome portfolio imbalance for traders of variable power from wind we have built an 'Imbalance Reduction System' (IRS) and performed a real-world field test with it, in which imbalance is minimized within a real-time electricity market portfolio, consisting of wind power and industrial and residential consumers and producers (Combined Heat and Power for district heating; residential heat pumps; industrial cold store; emergency generators). IRS uses the PowerMatcher concept, a coordination system for supply and demand of electricity in a which multi-agent system is combined with microeconomic principles. IRS appears to offer opportunities for embedding less predictable generators such as wind power more smoothly in the portfolio. We describe the context and operation of the Imbalance Reduction System and discuss a number of results from the performed field test. Also we introduce a business model for the balance responsible party, based on the e3-value method

  13. A Preliminary Model for Spacecraft Propulsion Performance Analysis Based on Nuclear Gain and Subsystem Mass-Power Balances

    Science.gov (United States)

    Chakrabarti, Suman; Schmidt, George R.; Thio, Y. C.; Hurst, Chantelle M.

    1999-01-01

    A preliminary model for spacecraft propulsion performance analysis based on nuclear gain and subsystem mass-power balances are presented in viewgraph form. For very fast missions with straight-line trajectories, it has been shown that mission trip time is proportional to the cube root of alpha. Analysis of spacecraft power systems via a power balance and examination of gain vs. mass-power ratio has shown: 1) A minimum gain is needed to have enough power for thruster and driver operation; and 2) Increases in gain result in decreases in overall mass-power ratio, which in turn leads to greater achievable accelerations. However, subsystem mass-power ratios and efficiencies are crucial: less efficient values for these can partially offset the effect of nuclear gain. Therefore, it is of interest to monitor the progress of gain-limited subsystem technologies and it is also possible that power-limited systems with sufficiently low alpha may be competitive for such ambitious missions. Topics include Space flight requirements; Spacecraft energy gain; Control theory for performance; Mission assumptions; Round trips: Time and distance; Trip times; Vehicle acceleration; and Minimizing trip times.

  14. Power conversion and balance of plant considerations for the STARFIRE commercial tokamak reactor

    International Nuclear Information System (INIS)

    Barry, K.; Graumann, D.

    1981-01-01

    The power conversion and balance of plant facilities for this tenth-of-a-kind tokamak fusion power plant are a combination of both features common to any large power plant, and elements peculiar to the fusion technology. For example, the steam generators, turbine-generator and main condenser components of the power conversion system and the natural draft cooling towers that are used for heat rejection at sites not close to a large body of water are generic to power plants. The tritium reprocessing facilities that minimize the tritium inventory in the plant, the Electrical and RF Power Supply Building that contains the coil and rf power supplies, the cryogenic facilities that provide liquid helium coolant for the superconducting coils, and the Hot Cell in which fully remote repair and maintenance functions are performed are unique to a fusion power plant. One of the major features of the STARFIRE design is steady state operation that maximizes overall facility reliability and eliminates both thermal storage requirements and potential power fluctuations on the grid. The reference reactor power is 4000 MWt with a gross electric power generation of 1440 MW. For STARFIRE, water is the preferred coolant and is utilized in both the first wall/blanket and limiter cooling circuits. Dual parallel primary coolant loops cool the twenty-four first-wall/blanket sectors. The power deposited in the limiter, approximately 5% of the total thermal power, is removed by the separate limiter/feedwater loop and is used for feedwater heating in the steam power conversion system

  15. Power supply-demand balance in a Smart Grid : An information sharing model for a market mechanism

    NARCIS (Netherlands)

    Larsen, Gunn K. H.; van Foreest, Nicky D.; Scherpen, Jacquelien M. A.

    2014-01-01

    In the future, global energy balance of a Smart Grid system can be achieved by its agents deciding on their own power demand and production (locally) and the exchange of these decisions. In this paper, we develop a network model that describes how the information of power imbalance of individual

  16. Norwegian power and energy balance towards the year of 2010; Norges effekt- og energibalanse frem mot aar 2010

    Energy Technology Data Exchange (ETDEWEB)

    Loekke, K.

    1996-12-31

    The present conference paper deals with the Norwegian power and energy balance towards the year of 2010 based on the rate of domestic energy consumption, development of new power plants, and international supply agreements. The efficiency of power transmission compared to the level of delivered energy in the Norwegian power grid within the period from 1975 to 1992 has increased from 83% to 91% with an equivalency of 5.5 TWh. Aspects in connection with the long-range programme are discussed. 12 figs.

  17. Balance of Power Theory: Implications for the U.S., Iran, Saudi Arabia, and a New Arms Race

    National Research Council Canada - National Science Library

    Turner, Randall G

    2008-01-01

    .... There is a balance of power struggle taking place between Iran and Saudi Arabia which, because of Iran's nuclear ambitions, has drawn the attention of the international community and the ire of the United States...

  18. French electric power balance sheet 2007

    International Nuclear Information System (INIS)

    Lartigau, Thierry; Pierron, Helene

    2008-01-01

    The mission of RTE, the French electricity Transportation grid, a public service assignment, is to balance the electricity supply and demand in real time. This report presents RTE's technical results for the year 2007: key figures of the electricity balance sheet, progresses in the implementation of market mechanisms, durable rise of RTE's investment, and RTE's commitment in sustainable development

  19. Maintenance management balancing performance maintenance and cost balance at reinforced concrete constructions of the fossil-fuel and nuclear power stations

    International Nuclear Information System (INIS)

    Ito, Hiroshi; Benno, Hiroshi; Ozaki, Mitsuhiro

    2003-01-01

    Life elongation of concrete constructions (CCs) is a very important needs for supporting future safe supply of electric power. However, some CCs constructed and used for a long term at fossil-fuel and nuclear power stations had reduction of their required performance by deterioration based on environmental and using conditions represented by salt-damage. As such constructions are anxious to increase in future, it is necessary to keep reliability of their establishments by providing desired rehabilitation to persist supplying effect of their facilities. On the other hand, as it is also essential to progress keeping and reducing cost of power generation together with development of recent liberalization of electric power, it is an important subject how to keep their performance maintenance and cost balance. Therefore, here were outlined on required performance setting method, inspection method, long-term deterioration forecasting and evaluating methods, selection method of countermeasure scenarios minimizing LCC, inspection period setting method, introduction of database and deterioration forecasting system, and so on, to economically maintain and manage already built reinforced concrete constructions at suitable materials and places to elongate their lives. (G.K.)

  20. Fuel balance in nuclear power with fast reactors without a uranium blanket

    International Nuclear Information System (INIS)

    Naumov, V.V.; Orlov, V.V.; Smirnov, V.S.

    1994-01-01

    General aspects related to replacing the uranium blanket of a lead-cooled fast reactor burning uranium-plutonium nitride fuel with a more efficient lead reflector are briefly discussed in the article. A study is very briefly summarized, which showed that a breeding ratio of about 1 and electric power of about 300 MW were achievable. A nuclear fuel balance is performed to estimate the increased consumption of uranium to produce power and the gains achievable by eliminating the uranium blanket. Elimination of the uranium blanket has the advantages of simplifying and improving the fast reactor and eliminating the production of weapons quality plutonium. 3 figs

  1. Validation of the thermal balance of Laguna Verde turbine under conditions of extended power increase; Validacion del balance termico de turbina de Laguna Verde en condiciones de aumento de potencia extendido

    Energy Technology Data Exchange (ETDEWEB)

    Castaneda G, M. A.; Cruz B, H. J.; Mercado V, J. J.; Cardenas J, J. B.; Garcia de la C, F. M., E-mail: miguel.castaneda01@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 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)

  2. The Power of Balance: Transforming Self, Society, and Scientific Inquiry

    Directory of Open Access Journals (Sweden)

    William R. Torbert

    2010-03-01

    Full Text Available The “power of balance” as conceived by Torbert represents an integral paradigm of principles, theory, and praxis. Deployed, the paradigm is one that can indeed inform and shape the development of self, society, and scientific inquiry. To explicate that fulsome vision, the book’s fifteen chapters develop the themes of three sections: Theory and Strategy, Heart and Practice, and Vision and Method. Here, we have excerpted from several chapters in Theory and Strategy, and from one chapter in Vision and Method. This means, of course, that we present but a small fraction of this integral classic, leaving out all of the rich, in-depth illustrations, including the author’s learning practice as he first attempted to enact the principles. Yet, we hope even this abbreviated form of The Power of Balance supports at least two goals: to offer deployable insights and practices for developing politics and the political; and to take root as part of a foundational canon for integral political thought, research, and praxis. How we readers deploy these principles in our own actions will determine the degree to which self, society, and scientific inquiry transform.

  3. Associations Between Measures of Balance and Lower-Extremity Muscle Strength/Power in Healthy Individuals Across the Lifespan: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Muehlbauer, Thomas; Gollhofer, Albert; Granacher, Urs

    2015-12-01

    It has frequently been reported that balance and lower-extremity muscle strength/power are associated with sports-related and everyday activities. Knowledge about the relationship between balance, strength, and power are important for the identification of at-risk individuals because deficits in these neuromuscular components are associated with an increased risk of sustaining injuries and falls. In addition, this knowledge is of high relevance for the development of specifically tailored health and skill-related exercise programs. The objectives of this systematic literature review and meta-analysis were to characterize and, if possible, quantify associations between variables of balance and lower-extremity muscle strength/power in healthy individuals across the lifespan. A computerized systematic literature search was performed in the electronic databases PubMed, Web of Science, and SPORTDiscus up to March 2015 to capture all relevant articles. A systematic approach was used to evaluate the 996 articles identified for initial review. Studies were included only if they investigated healthy individuals aged ≥6 years and tested at least one measure of static steady-state balance (e.g., center of pressure [CoP] displacement during one-legged stance), dynamic steady-state balance (e.g., gait speed), proactive balance (e.g., distance in the functional-reach-test), or reactive balance (e.g., CoP displacement during perturbed one-legged stance), and one measure of maximal strength (e.g., maximum voluntary contraction), explosive force (e.g., rate of force development), or muscle power (e.g., jump height). In total, 37 studies met the inclusionary criteria for review. The included studies were coded for the following criteria: age (i.e., children: 6-12 years, adolescents: 13-18 years, young adults: 19-44 years, middle-aged adults: 45-64 years, old adults: ≥65 years), sex (i.e., female, male), and test modality/outcome (i.e., test for the assessment of balance

  4. Development of technologies on innovative-simplified nuclear power plant using high-efficiency steam injectors. (2) Analysis of heat balance of innovative-simplified nuclear power plant

    International Nuclear Information System (INIS)

    Goto, Shoji; Ohmori, Shuichi; Mori, Mitchitsugu

    2004-01-01

    It is possible to established simplified systems and reduced space and equipments using high-efficiency Steam Injector (SI) instead of low-pressure feed water heaters in Nuclear Power Plant (NPP). The SI works as a heat exchanger through direct contact between feedwater from condenser and extracted steam from turbine. It can get a higher pressure than supplied steam pressure, so it can reduce the feedwater pumps. The maintenance and reliability are still higher because SI has no movable parts. This paper describes the analysis of the heat balance and plant efficiency of this Innovative-Simplified NPP with high-efficiency SI. The plant efficiency is compared with the electric power of 1100MWe class original BWR system and the Innovative-Simplified BWR system with SI. The SI model is adapted into the heat balance simulator with a simplified model. The results show plant efficiencies of the Innovated-Simplified BWR system are almost equal to the original BWR one. The present research is one of the projects that are carried out by Tokyo Electric Power Company, Toshiba Corporation, and six Universities in Japan, funded from the Institute of Applied Energy (IAE) of Japan as the national public research-funded program. (author)

  5. Classification and quantification of reserve requirements for balancing

    NARCIS (Netherlands)

    Frunt, J.; Kling, W.L.; Bosch, van den P.P.J.

    2010-01-01

    In electrical power systems there must always be a balance between supply and demand of power. Any imbalance will result in a frequency deviation. To reduce the imbalance to zero, ancillary services for balance management are in use. Ancillary services for balance management are characterized by

  6. Dynamic modelling of balance of plant systems for a pulsed DEMO power plant

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, C., E-mail: Chris.Harrington@ccfe.ac.uk

    2015-10-15

    Highlights: • A fully dynamic model of the balance of plant systems for pulsed DEMO is presented. • An operating strategy for handling pulse/dwell transitions has been devised. • Operation of a water-cooled system without energy storage appears feasible. • Steam turbine cycling can be minimised if rotation speed is maintained. - Abstract: The current baseline concept for a European DEMO defines a pulsed reactor producing power for periods of 2–4 h at a time, interrupted by dwell periods of approximately half an hour, potentially leading to cyclic fatigue of the heat transfer system and power generation equipment. Thermal energy storage systems could mitigate pulsing issues; however, the requirements for such a system cannot be defined without first understanding the challenges for pulsed operation, while any system will simultaneously increase the cost and complexity of the balance of plant. This work therefore presents a dynamic model of the primary heat transfer system and associated steam plant for a water-cooled DEMO, without energy storage, capable of simulating pulsed plant operation. An operating regime is defined such that the primary coolant flows continuously throughout the dwell period while the secondary steam flow is reduced. Simulation results show minimised thermal and pressure transients in the primary circuit, and small thermally induced stresses on the steam turbine rotor. If the turbine can be kept spinning to also minimise mechanical cycling, pulsed operation of a water-cooled DEMO without thermal energy storage may be feasible.

  7. Lower-extremity resistance training on unstable surfaces improves proxies of muscle strength, power and balance in healthy older adults: a randomised control trial.

    Science.gov (United States)

    Eckardt, Nils

    2016-11-24

    It is well documented that both balance and resistance training have the potential to mitigate intrinsic fall risk factors in older adults. However, knowledge about the effects of simultaneously executed balance and resistance training (i.e., resistance training conducted on unstable surfaces [URT]) on lower-extremity muscle strength, power and balance in older adults is insufficient. The objective of the present study was to compare the effects of machine-based stable resistance training (M-SRT) and two types of URT, i.e., machine-based (M-URT) and free-weight URT (F-URT), on measures of lower-extremity muscle strength, power and balance in older adults. Seventy-five healthy community-dwelling older adults aged 65-80 years, were assigned to three intervention groups: M-SRT, M-URT and F-URT. Over a period of ten weeks, all participants exercised two times per week with each session lasting ~60 min. Tests included assessment of leg muscle strength (e.g., maximal isometric leg extension strength), power (e.g., chair rise test) and balance (e.g., functional reach test), carried out before and after the training period. Furthermore, maximal training load of the squat-movement was assessed during the last training week. Maximal training load of the squat-movement was significantly lower in F-URT in comparison to M-SRT and M-URT. However, lower-extremity resistance training conducted on even and uneven surfaces meaningfully improved proxies of strength, power and balance in all groups. M-URT produced the greatest improvements in leg extension strength and F-URT in the chair rise test and functional reach test. Aside from two interaction effects, overall improvements in measures of lower-extremity muscle strength, power and balance were similar across training groups. Importantly, F-URT produced similar results with considerably lower training load as compared to M-SRT and M-URT. Concluding, F-URT seems an effective and safe alternative training program to mitigate

  8. Joint Optimization of Power Allocation and Load Balancing for Hybrid VLC/RF Networks

    KAUST Repository

    Obeed, Mohanad; Salhab, Anas; Zummo, Salam A.; Alouini, Mohamed-Slim

    2018-01-01

    In this paper, we propose and study a new joint load balancing (LB) and power allocation (PA) scheme for a hybrid visible light communication (VLC) and radio frequency (RF) system consisting of one RF access point (AP) and multiple VLC APs. An iterative algorithm is proposed to distribute users on APs and distribute the powers of the APs on their users. In the PA subproblem, an optimization problem is formulated to allocate the power of each AP to the connected users for total achievable data rate maximization. In this subproblem, we propose a new efficient algorithm that finds optimal dual variables after formulating them in terms of each other. This new algorithm provides faster convergence and better performance than the traditional subgradient method. In addition, it does not depend on the step size or the initial values of the variables, which we look for, as the subgradient does. Then, we start with the user of the minimum data rate seeking another AP that offers a higher data rate for that user. Users with lower data rates continue reconnecting from one AP to another to balance the load only if this travel increases the summation of the achievable data rates and enhances the system fairness. Two approaches are proposed to have the joint PA and LB performed: a main approach that considers the exact interference information for all users, and a suboptimal approach that aims to decrease the complexity of the first approach by considering only the approximate interference information of users. The numerical results demonstrate that the proposed algorithms improve the system capacity and system fairness with fast convergence.

  9. Joint Optimization of Power Allocation and Load Balancing for Hybrid VLC/RF Networks

    KAUST Repository

    Obeed, Mohanad

    2018-04-18

    In this paper, we propose and study a new joint load balancing (LB) and power allocation (PA) scheme for a hybrid visible light communication (VLC) and radio frequency (RF) system consisting of one RF access point (AP) and multiple VLC APs. An iterative algorithm is proposed to distribute users on APs and distribute the powers of the APs on their users. In the PA subproblem, an optimization problem is formulated to allocate the power of each AP to the connected users for total achievable data rate maximization. In this subproblem, we propose a new efficient algorithm that finds optimal dual variables after formulating them in terms of each other. This new algorithm provides faster convergence and better performance than the traditional subgradient method. In addition, it does not depend on the step size or the initial values of the variables, which we look for, as the subgradient does. Then, we start with the user of the minimum data rate seeking another AP that offers a higher data rate for that user. Users with lower data rates continue reconnecting from one AP to another to balance the load only if this travel increases the summation of the achievable data rates and enhances the system fairness. Two approaches are proposed to have the joint PA and LB performed: a main approach that considers the exact interference information for all users, and a suboptimal approach that aims to decrease the complexity of the first approach by considering only the approximate interference information of users. The numerical results demonstrate that the proposed algorithms improve the system capacity and system fairness with fast convergence.

  10. Can the Power Balance® Bracelet Improve Balance, Flexibility, Strength, and Power?

    OpenAIRE

    Porcari, John; Hazuga, Rachel; Foster, Carl; Doberstein, Scott; Becker, Jordan; Kline, Dennis; Mickschl, Thomas; Dodge, Chris

    2011-01-01

    Athletes are constantly searching for something that will give them a competitive edge. Performance jewelry is one of the latest products on the market designed to improve athletic performance. The most common claims are that wearing this performance jewelry will improve flexibility, balance, and strength. There is considerable marketing of these products, including testimonial evidence by high profile athletes, in support of the purported benefits. In demonstrations designed to validate the ...

  11. Heat flux estimates of power balance on Proto-MPEX with IR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Showers, M., E-mail: mshower1@vols.utk.edu [Bredesen Center, University of Tennessee, Knoxville, Tennessee 37996 (United States); Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Biewer, T. M.; Caughman, J. B. O.; Goulding, R. H.; Rapp, J. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Donovan, D. C. [Bredesen Center, University of Tennessee, Knoxville, Tennessee 37996 (United States)

    2016-11-15

    The Prototype Material Plasma Exposure eXperiment (Proto-MPEX) at Oak Ridge National Laboratory (ORNL) is a precursor linear plasma device to the Material Plasma Exposure eXperiment (MPEX), which will study plasma material interactions (PMIs) for future fusion reactors. This paper will discuss the initial steps performed towards completing a power balance on Proto-MPEX to quantify where energy is lost from the plasma, including the relevant diagnostic package implemented. Machine operating parameters that will improve Proto-MPEX’s performance may be identified, increasing its PMI research capabilities.

  12. Heat flux estimates of power balance on Proto-MPEX with IR imaging

    International Nuclear Information System (INIS)

    Showers, M.; Biewer, T. M.; Caughman, J. B. O.; Goulding, R. H.; Rapp, J.; Donovan, D. C.

    2016-01-01

    The Prototype Material Plasma Exposure eXperiment (Proto-MPEX) at Oak Ridge National Laboratory (ORNL) is a precursor linear plasma device to the Material Plasma Exposure eXperiment (MPEX), which will study plasma material interactions (PMIs) for future fusion reactors. This paper will discuss the initial steps performed towards completing a power balance on Proto-MPEX to quantify where energy is lost from the plasma, including the relevant diagnostic package implemented. Machine operating parameters that will improve Proto-MPEX’s performance may be identified, increasing its PMI research capabilities.

  13. Evaluation of actual costs of power sources and effects on balance sheets of electric utilities

    International Nuclear Information System (INIS)

    Matsuo, Yuji; Yamaguchi, Yuji; Murakami, Tomoko

    2013-01-01

    After the Fukushima nuclear accident, almost all nuclear power stations continued to stop operation and sharp increase of purchase costs of fossil fuels forced some electric utilities to suffer a deficit. This article presented quantitative analysis of effects of present state on power costs and balance sheets of electric utilities. Levelized costs of electricity increased from 8.6 ¥/kWh (2010) to 11.6 ¥/kWh (2011) and 12.6 ¥/kWh (2012). Total power costs increased from 7.5 Trillion¥(2010) to 9.5 Trillion¥(2011). Due to increase of cost of fossil fuel compensated for nuclear power, electric utilities suffered a net loss of 0.8 Trillion¥ and decreased surplus to 2.5 Trillion¥ in 2011. Net loss of 1.3 Trillion¥ and surplus of 1.2 Trillion¥ was estimated for 2012. This state was beyond the limit of utilities' efforts to reduce costs and uncertain share of power sources became a great risk. Future share of power sources should be judged appropriately from various standpoints (costs, stable supply, energy security and national economic growth) and early public dissemination of new philosophy on share of power sources was highly required. (T. Tanaka)

  14. Balancing Act

    Science.gov (United States)

    Part of being an Active, More Powerful You means finding balance in your daily life: taking on the Must-dos and finding time for some Should Dos and Want-to-Dos. Sometimes, emotions and commitments can come into play and upset the balance.

  15. Child abuse and the balance of power in parental relationships: an evolved domain-independent mental mechanism that accounts for behavioral variation.

    Science.gov (United States)

    Handwerker, W P

    2001-01-01

    Previous studies use zero-order analyses to show a link between child abuse and exposure to "stepfathers." These studies rest on a proposed evolved, domain-specific cognitive mechanism that induces adult males to abuse or kill offspring not their own and, so, contribute directly to reproductive success. However, child abuse may reflect an evolved neurological mechanism that creates behavioral plasticity and adaptability by assigning emotional weights (which in consciousness appear rationalized as costs and benefits) to choice alternatives in all behavioral domains. This mechanism should act as a selective mechanism to create enhanced ability to avoid predation (social exploitation) and to obtain access to resources, given the properties of specific ecosystems, and should control behavioral responses to variation in the balance of power in social relationships. Power equalities should elicit good treatment for both parties; power inequalities, by contrast, should elicit exploitative and coercive behavior on the part of those who hold the balance of power. This paper reports a test of both hypotheses simultaneously, controlling for a standard social science risk factor (growing up in poverty). Once we control for the balance of power in parental relationships, exposure to a stepfather and growing up in poverty show no effect on the intensity of child abuse. Powerful women negotiated affectionate behavior from their partners for both themselves and their children; powerless women's negotiations with partners usually left both themselves and their children open to violence.

  16. Development of a PEMFC Power System with Integrated Balance of Plant

    Science.gov (United States)

    Wynne, B.; Diffenderfer, C.; Ferguson, S.; Keyser, J.; Miller, M.; Sievers, B.; Ryan, A.; Vasquez, A.

    2012-01-01

    Autonomous Underwater Vehicles (AUV s) have received increasing attention in recent years as military and commercial users look for means to maintain a mobile and persistent presence in the undersea world. Compact, neutrally buoyant power systems are needed for both small and large vehicles. Batteries are usually employed in these applications, but the energy density and therefore the mission duration are limited with current battery technology. At a certain energy or mission duration requirement, other means to get long duration power become feasible. For example, above 10 kW-hrs liquid oxygen and hydrogen have better specific energy than batteries and are preferable for energy storage as long as a compact system of about 100 W/liter is achievable to convert the chemical energy in these reactants into power. Other reactant forms are possible, such as high pressure gas, chemical hydrides or oxygen carriers, but it is essential that the power system be small and light weight. Recent fuel cell work, primarily focused on NASA applications, has developed power systems that can meet this target power density. Passive flow-through systems, using ejector driven reactant (EDR) flow, integrated into a compact balance of plant have been developed. These systems are thermally and functionally integrated in much the same way as are automotive, air breathing fuel cell systems. These systems fit into the small volumes required for AUV and future NASA applications. Designs have been developed for both a 21" diameter and a larger diameter (LD) AUV. These fuel cell systems occupy a very small portion of the overall energy system, allowing most of the system volume to be used for the reactants. The fuel cell systems have been optimized to use reactants efficiently with high stack efficiency and low parasitic losses. The resulting compact, highly efficient fuel cell system provides exceptional reactant utilization and energy density. Key design variables and supporting test data are

  17. Development of technologies on innovative-simplified nuclear power plant using high-efficiency steam injectors (2) analysis of heat balance of innovative-simplified nuclear power plant

    International Nuclear Information System (INIS)

    Goto, S.; Ohmori, S.; Mori, M.

    2005-01-01

    It is possible to establish simplified system with reduced space and total equipment weight using high-efficiency Steam Injector (SI) instead of low-pressure feedwater heaters in Nuclear Power Plant (NPP)(1)-(6). The SI works as a heat exchanger through direct contact between feedwater from the condensers and extracted steam from the turbines. It can get a higher pressure than supplied steam pressure, so it can reduce the feedwater pumps. The maintenance and reliability are still higher because SI has no movable parts. This paper describes the analysis of the heat balance and plant efficiency of this Innovative- Simplified NPP with high-efficiency SI. The plant efficiency is compared with the electric power of 1100MWe-class BWR system and the Innovative- Simplified BWR system with SI. The SI model is adapted into the heat balance simulator with a simplified model. The results show plant efficiencies of the Innovated-Simplified BWR system are almost equal to the original BWR one. The present research is one of the projects that are carried out by Tokyo Electric Power Company, Toshiba Corporation, and six Universities in Japan, funded from the Institute of Applied Energy (IAE) of Japan as the national public research-funded program. (authors)

  18. Lower-extremity resistance training on unstable surfaces improves proxies of muscle strength, power and balance in healthy older adults: a randomised control trial

    Directory of Open Access Journals (Sweden)

    Nils Eckardt

    2016-11-01

    Full Text Available Abstract Background It is well documented that both balance and resistance training have the potential to mitigate intrinsic fall risk factors in older adults. However, knowledge about the effects of simultaneously executed balance and resistance training (i.e., resistance training conducted on unstable surfaces [URT] on lower-extremity muscle strength, power and balance in older adults is insufficient. The objective of the present study was to compare the effects of machine-based stable resistance training (M-SRT and two types of URT, i.e., machine-based (M-URT and free-weight URT (F-URT, on measures of lower-extremity muscle strength, power and balance in older adults. Methods Seventy-five healthy community-dwelling older adults aged 65–80 years, were assigned to three intervention groups: M-SRT, M-URT and F-URT. Over a period of ten weeks, all participants exercised two times per week with each session lasting ~60 min. Tests included assessment of leg muscle strength (e.g., maximal isometric leg extension strength, power (e.g., chair rise test and balance (e.g., functional reach test, carried out before and after the training period. Furthermore, maximal training load of the squat-movement was assessed during the last training week. Results Maximal training load of the squat-movement was significantly lower in F-URT in comparison to M-SRT and M-URT. However, lower-extremity resistance training conducted on even and uneven surfaces meaningfully improved proxies of strength, power and balance in all groups. M-URT produced the greatest improvements in leg extension strength and F-URT in the chair rise test and functional reach test. Conclusion Aside from two interaction effects, overall improvements in measures of lower-extremity muscle strength, power and balance were similar across training groups. Importantly, F-URT produced similar results with considerably lower training load as compared to M-SRT and M-URT. Concluding, F-URT seems an

  19. A Systematic Review of the Association Between Physical Fitness and Musculoskeletal Injury Risk: Part 3 - Flexibility, Power, Speed, Balance, and Agility.

    Science.gov (United States)

    de la Motte, Sarah J; Lisman, Peter; Gribbin, Timothy C; Murphy, Kaitlin; Deuster, Patricia A

    2017-12-11

    We performed a systematic review and evaluation of the existing scientific literature on the association between flexibility, power, speed, balance, and agility, and musculoskeletal injury (MSK-I) risk in military and civilian populations. MEDLINE, EBSCO, EMBASE, and the Defense Technical Information Center were searched for original studies published from 1970 through 2015 that examined associations between these physical fitness measures (flexibility, power, speed, balance, and agility) and MSK-I. Methodological quality and strength of the evidence were determined following criteria adapted from previously published systematic reviews. Twenty-seven of 4,229 citations met our inclusion criteria. Primary findings indicate there is (a) moderate evidence that hamstring flexibility, as measured by performance on a sit-and-reach test or active straight-leg raise test assessed with goniometry, and ankle flexibility, assessed with goniometry, are associated with MSK-I risk; (b) moderate evidence that lower body power, as measured by performance on a standing broad jump or vertical jump with no countermovement, is associated with MSK-I risk; (c) moderate evidence that slow sprint speed is associated with MSK-I risk; (d) moderate evidence that poor performance on a single-leg balance test is associated with increased risk for ankle sprain; and (e) insufficient evidence that agility is associated with MSK-I risk. Several measures of flexibility, power, speed, and balance are risk factors for training-related MSK-I in military and civilian athletic populations. Importantly, these findings can be useful for military, first responder, and athletic communities who are seeking evidence-based metrics for assessing or stratifying populations for risk of MSK-I.

  20. Experimental evaluation of the power balance model of speed skating.

    Science.gov (United States)

    de Koning, Jos J; Foster, Carl; Lampen, Joanne; Hettinga, Floor; Bobbert, Maarten F

    2005-01-01

    Prediction of speed skating performance with a power balance model requires assumptions about the kinetics of energy production, skating efficiency, and skating technique. The purpose of this study was to evaluate these parameters during competitive imitations for the purpose of improving model predictions. Elite speed skaters (n = 8) performed races and submaximal efficiency tests. External power output (P(o)) was calculated from movement analysis and aerodynamic models and ice friction measurements. Aerobic kinetics was calculated from breath-by-breath oxygen uptake (Vo(2)). Aerobic power (P(aer)) was calculated from measured skating efficiency. Anaerobic power (P(an)) kinetics was determined by subtracting P(aer) from P(o). We found gross skating efficiency to be 15.8% (1.8%). In the 1,500-m event, the kinetics of P(an) was characterized by a first-order system as P(an) = 88 + 556e(-0.0494t) (in W, where t is time). The rate constant for the increase in P(aer) was -0.153 s(-1), the time delay was 8.7 s, and the peak P(aer) was 234 W; P(aer) was equal to 234[1 - e(-0.153(t-8.7))] (in W). Skating position changed with preextension knee angle increasing and trunk angle decreasing throughout the event. We concluded the pattern of P(aer) to be quite similar to that reported during other competitive imitations, with the exception that the increase in P(aer) was more rapid. The pattern of P(an) does not appear to fit an "all-out" pattern, with near zero values during the last portion of the event, as assumed in our previous model (De Koning JJ, de Groot G, and van Ingen Schenau GJ. J Biomech 25: 573-580, 1992). Skating position changed in ways different from those assumed in our previous model. In addition to allowing improved predictions, the results demonstrate the importance of observations in unique subjects to the process of model construction.

  1. Discussion on management of earth and rock balancing during the construction of Fuqing nuclear power plant

    International Nuclear Information System (INIS)

    Yan Yingdi; Gu Jian

    2013-01-01

    The main purpose of earth and stone work for Fuqing nuclear power plant is to solve problems of the main plant and the temporary accommodation site and also providing aggregate, marine stone and backfill as well. For a reasonable arrangement of stacking, using and spoiling, a dynamic balance management is performed in the project based on the initial design by the plant design institute. The design result would be used to conduct the construction arrangement, for avoiding the risk of earth and stone shortage, and enhancing the economic benefits. By discussing on problems existed in the balanced management of earth and stone, some suggestions are raised in this paper for optimizing earth and stone medium-and long-term management. (authors)

  2. Alfacalcidol improves muscle power, muscle function and balance in elderly patients with reduced bone mass.

    Science.gov (United States)

    Schacht, E; Ringe, Johann D

    2012-01-01

    We investigated the effect of daily therapy with 1 mcg alfacalcidol (Doss(®)-TEVA/AWD-pharma) on muscle power, muscle function, balance performance and fear of falls in an open, multi-centered, uncontrolled, prospective study on a cohort of patients with reduced bone mass. Among the 2,097 participants, 87.1% were post-menopausal women and 12.9% were men. Mean age was 74.8 years and mean body mass index (BMI) 26.3 kg/m². A total of 75.3% of the study population had osteoporosis, 81% a diagnosis of "increased risk of falls" and 70.1% had a creatinine clearance (CrCl) of power tests at onset and after 3 and 6 months: the timed up and go test (TUG) and the chair rising test (CRT). At baseline and after 6 months, participants performed the tandem gait test (TGT) and filled out a questionnaire evaluating fear of falling. Successful performance in the muscle tests is associated with a significantly lower risk of falls and non-vertebral fractures in elderly patients (successful test performance: TUG ≤ 10 s (sec), CRT ≤ 10 s, TGT ≥ 8 steps). A significant improvement in the performance of the two muscle tests was proved already after 3 months of treatment with alfacalcidol and further increased by the end of the therapeutic intervention. There were significant increases in the number of participants able to successfully perform the tests: 24.6% at baseline and 46.3% at the end of trial for the TUG (P balance test (TGT) increased from 36.0% at onset to 58.6% at the end of the trial (P power, muscle function and balance and reduces fear of falls. The significant improvement in the three muscle and balance tests and fear of falls may have a preventative effect on falls and fractures. We suggest that the quantitative risk tests used in this study could be reliable surrogate parameters for the risk of falls and fractures in elderly patients.

  3. One session of high-intensity interval training (HIIT) every 5 days, improves muscle power but not static balance in lifelong sedentary ageing men

    Science.gov (United States)

    Sculthorpe, Nicholas F.; Herbert, Peter; Grace, Fergal

    2017-01-01

    Abstract Background: Declining muscle power during advancing age predicts falls and loss of independence. High-intensity interval training (HIIT) may improve muscle power, but remains largely unstudied in ageing participants. Methods: This randomized controlled trial (RCT) investigated the efficacy of a low-frequency HIIT (LfHIIT) intervention on peak muscle power (peak power output [PPO]), body composition, and balance in lifelong sedentary but otherwise healthy males. Methods: Thirty-three lifelong sedentary ageing men were randomly assigned to either intervention (INT; n = 22, age 62.3 ± 4.1 years) or control (n = 11, age 61.6 ± 5.0 years) who were both assessed at 3 distinct measurement points (phase A), after 6 weeks of conditioning exercise (phase B), and after 6 weeks of HIIT once every 5 days in INT (phase C), where control remained inactive throughout the study. Results: Static balance remained unaffected, and both absolute and relative PPO were not different between groups at phases A or B, but increased significantly in INT after LfHIIT (P balance in sedentary ageing men. PMID:28178145

  4. A simulation of cross-country skiing on varying terrain by using a mathematical power balance model.

    Science.gov (United States)

    Moxnes, John F; Sandbakk, Oyvind; Hausken, Kjell

    2013-01-01

    The current study simulated cross-country skiing on varying terrain by using a power balance model. By applying the hypothetical inductive deductive method, we compared the simulated position along the track with actual skiing on snow, and calculated the theoretical effect of friction and air drag on skiing performance. As input values in the model, air drag and friction were estimated from the literature, whereas the model included relationships between heart rate, metabolic rate, and work rate based on the treadmill roller-ski testing of an elite cross-country skier. We verified this procedure by testing four models of metabolic rate against experimental data on the treadmill. The experimental data corresponded well with the simulations, with the best fit when work rate was increased on uphill and decreased on downhill terrain. The simulations predicted that skiing time increases by 3%-4% when either friction or air drag increases by 10%. In conclusion, the power balance model was found to be a useful tool for predicting how various factors influence racing performance in cross-country skiing.

  5. An evaluation of the power-to-gas concept in the balancing energy marker; Eine Bewertung der Regelenergievermarktung im Power-to-Gas-Konzept

    Energy Technology Data Exchange (ETDEWEB)

    Michaelis, Julia; Junker, Julian; Wietschel, Martin [Fraunhofer-Institut fuer System- und Innovationsforschung ISI, Karlsruhe (Germany)

    2013-09-15

    The integration of the increasing share of fluctuating renewable energy sources into the energy system requires more options in flexibility. A promising attempt is the power-to-gas concept (PtG) which allows the production of hydrogen and synthetic natural gas (SNG) from electricity and the storage in caverns or existing gas storage facilities. However, an economic operation in Germany is not expected before 2030, when the amount of surplus energy, mainly generated in wind parks, will be sufficient. Currently, a hardly analyzed aspect is the potential commercialization of the flexible electrolysis as controllable load on the electricity balancing market. This offers opportunities to generate additional revenues and to obtain cheap electricity in the form of balancing energy. The present article has been designed to analyze this aspect and to examine the impact of a potential commercialization of balancing energy on the gas production costs within the PtG concept. At first, the current legal framework, the funding instruments of SNG and the differences between the notion 'Speichergas' and 'Biogas' will be outlined. An overview of the current balancing market will be given and the development of prices on the secondary balancing market will be evaluated as well as expected market trends will be presented. The following calculation of gas production costs, which result from applying an optimal proposal strategy on the secondary balancing market, is model-based and uses historical data. Three scenarios are defined and examined, and the impact of variable electricity prices is analyzed. The electricity balancing market is profitable and offers many opportunities for PtG plants. The results show a decrease of SNG production costs by up to 74 % to 46,9 Euro/MWh. As for the hydrogen, the production costs amount to approximately 25,8 Euro/MWh which equals a cost reduction of up to 81 % compared to conventional PtG plants without commercialization of

  6. An ultrasound mini-balance for measurement of therapy level ultrasound

    International Nuclear Information System (INIS)

    Sutton, Yvonne; McBride, Karne; Pye, Stephen

    2006-01-01

    This paper describes a cost-effective method for measuring acoustic power using a radiation force balance. The device is based around a long established balance design with a gantry arrangement fitted with an absorbing target. The notion of this balance design is that it can easily be constructed from materials that would be readily available within a clinical or industrial environment. The mini-balance was calibrated using a transfer standard against an NPL Reference balance, so a comparison of the performance between the two systems could be assessed. The measurements were completed at 1 MHz and 3 MHz and over the acoustic power range of 1 W to 15 W. The results show the acoustic power measured on the mini-balance to be within 5% of the reference measurements made on the NPL Balance. A separate systematic uncertainty budget is also presented based on studies made on the balance and on similar systems. The overall expanded uncertainty was calculated to be within 14% at 1 W level, decreasing with increasing power level to 7.4% above 5 W

  7. Confinement and power balance in the S-1 spheromak

    Energy Technology Data Exchange (ETDEWEB)

    Levinton, F.M.; Meyerhofer, D.D.; Mayo, R.M.; Janos, A.C.; Ono, Y.; Ueda, Y.; Yamada, M.

    1989-07-01

    The confinement and scaling features of the S-1 spheromak have been investigated using magnetic, spectroscopic, and Thomson scattering data in conjunction with numerical modeling. Results from the multipoint Thomson scattering diagnostic shows that the central beta remains constant (/beta//sub to/ /approximately/ 5%) as the plasma current density increases from 0.68--2.1 MA/m/sup 2/. The density is observed to increase slowly over this range, while the central electron temperature increases much more rapidly. Analysis of the global plasma parameters shows a decrease in the volume average beta and energy confinement as the total current is increased. The power balance has been modeled numerically with a 0-D non-equilibrium time-dependent coronal model and is consistent with the experimental observations. 20 refs., 12 figs., 2 tabs.

  8. Confinement and power balance in the S-1 spheromak

    International Nuclear Information System (INIS)

    Levinton, F.M.; Meyerhofer, D.D.; Mayo, R.M.; Janos, A.C.; Ono, Y.; Ueda, Y.; Yamada, M.; Rochester Univ., NY; Los Alamos National Lab., NM; Princeton Univ., NJ

    1989-07-01

    The confinement and scaling features of the S-1 spheromak have been investigated using magnetic, spectroscopic, and Thomson scattering data in conjunction with numerical modeling. Results from the multipoint Thomson scattering diagnostic shows that the central beta remains constant (β to ∼ 5%) as the plasma current density increases from 0.68--2.1 MA/m 2 . The density is observed to increase slowly over this range, while the central electron temperature increases much more rapidly. Analysis of the global plasma parameters shows a decrease in the volume average beta and energy confinement as the total current is increased. The power balance has been modeled numerically with a 0-D non-equilibrium time-dependent coronal model and is consistent with the experimental observations. 20 refs., 12 figs., 2 tabs

  9. Power-balancing instantaneous optimization energy management for a novel series-parallel hybrid electric bus

    Science.gov (United States)

    Sun, Dongye; Lin, Xinyou; Qin, Datong; Deng, Tao

    2012-11-01

    Energy management(EM) is a core technique of hybrid electric bus(HEB) in order to advance fuel economy performance optimization and is unique for the corresponding configuration. There are existing algorithms of control strategy seldom take battery power management into account with international combustion engine power management. In this paper, a type of power-balancing instantaneous optimization(PBIO) energy management control strategy is proposed for a novel series-parallel hybrid electric bus. According to the characteristic of the novel series-parallel architecture, the switching boundary condition between series and parallel mode as well as the control rules of the power-balancing strategy are developed. The equivalent fuel model of battery is implemented and combined with the fuel of engine to constitute the objective function which is to minimize the fuel consumption at each sampled time and to coordinate the power distribution in real-time between the engine and battery. To validate the proposed strategy effective and reasonable, a forward model is built based on Matlab/Simulink for the simulation and the dSPACE autobox is applied to act as a controller for hardware in-the-loop integrated with bench test. Both the results of simulation and hardware-in-the-loop demonstrate that the proposed strategy not only enable to sustain the battery SOC within its operational range and keep the engine operation point locating the peak efficiency region, but also the fuel economy of series-parallel hybrid electric bus(SPHEB) dramatically advanced up to 30.73% via comparing with the prototype bus and a similar improvement for PBIO strategy relative to rule-based strategy, the reduction of fuel consumption is up to 12.38%. The proposed research ensures the algorithm of PBIO is real-time applicability, improves the efficiency of SPHEB system, as well as suite to complicated configuration perfectly.

  10. Lower limb power rehabilitation (LLPR) using interactive video game for improvement of balance function in older people.

    Science.gov (United States)

    Chen, Po-Yin; Wei, Shun-Hwa; Hsieh, Wan-Ling; Cheen, Jang-Rong; Chen, Liang-Kung; Kao, Chung-Lan

    2012-01-01

    Declined balance functions have adverse effects on elderly population. Lower limbs muscle power training is currently an emerging concept in rehabilitation on individuals with decreased balance and mobility. In this prospective, controlled study, we used a human-computer interactive video-game-based rehabilitation device (LLPR) for training of lower limb muscle power in the elderly. Forty (aged >65 years) individuals were recruited from the community. Twenty participants in the exercise group received 30-min training, twice a week, using the LLPR system. The LLPR system allows participants to perform fast speed sit-to-stand (STS) movements. Twenty age-matched participants in the control group performed slow speed STS movements, as well as strengthening and balance exercises, with the same frequency and duration. The results were compared after 12 sessions (6 weeks) of training. The mechanical and time parameters during STS movement were measured using the LLPR system. Modified falls efficacy scale (MFES), Tinetti Performance-Oriented Mobility Assessment (POMA), function reach test, five times sit to stand (FTSS) and Timed Up and Go (TUG) were administered to participants as clinical assessments. Results showed that in the exercise group, all the mechanical and time parameters showed significant improvement. In control group, only the maximal vertical ground reaction force (MVGRF) improved significantly. For clinical assessments (balance, mobility, and self-confidence), exercise group showed significantly better scores. The STS movements in video-game-based training mimic real life situations which may help to transfer the training effects into daily activities. The effectiveness of lower limb muscle training is worthy of further investigation. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  11. Balancing power: A grounded theory study on partnership of academic service institutes.

    Science.gov (United States)

    Heshmati Nabavi, Fatemeh; Vanaki, Zohreh; Mohammadi, Eesa; Yazdani, Shahram

    2017-07-01

    Governments and professional organizations have called for new partnerships between health care providers and academics to improve clinical education for the benefit of both students and patients. To develop a substantive grounded theory on the process of forming academic-service partnerships in implementing clinical education, from the perspective of academic and clinical nursing staff members and managers working in Iranian settings. The participants included 15 hospital nurses, nurse managers, nurse educators, and educational managers from two central universities and clinical settings from 2009 to 2012. Data were collected through 30 in-depth, semi-structure interviews with the individual participants and then analyzed using the methodology of Strauss and Corbin's grounded theory. Utilizing "balancing power" as the core variable enabled us to integrate the concepts concerning the partnership processes between clinical and educational institutes. Three distinct and significant categories emerged to explain the process of partnership: 1) divergence, 2) conflict between educational and caring functions, and 3) creation of balance between educational and caring functions. In implementing clinical education, partnerships have been formed within a challenging context in Iran. Conflict between clinical and educational functions was the main concern of both sides of the partnership in forming a collaborative relationship, with our findings emphasizing the importance of nursing educators' role in the establishment of partnership programs.

  12. Conception of programs for evaluating balance indices of operation of WWER-440 nuclear power plants

    International Nuclear Information System (INIS)

    Zadrazil, J.

    1986-01-01

    The procedures are discussed of writing computation programs for the evaluation of basic technical and economic parameters of the operation of WWER-440 nuclear power plants. The criterion of the evaluation is the maximum power supply to the grid together with the required supply of heat, with the observance of safe operating conditions. Previous procedures of evaluation are compared with present procedures based on the use of a monitoring and evaluation system of the KOMPLEX-URAN 2 M type. The mathematical model of the program is based on balance equations and relations derived for actual measuring systems and is completed with an assessment of the reliability of input and output data. The flow chart is shown of the algorithm for the evaluation of technical and economic parameters, and methods are suggested for improving and extending the program. (J.C.)

  13. ANALYSIS OF THE HARMONIC LOSSES WITH ARTIFICIAL NEURAL NETWORKS IN UNBALANCED SYSTEM LOSSES USING BALANCED ELECTRIC POWER SYSTEM DATA

    Directory of Open Access Journals (Sweden)

    Aslan İNAN

    2005-01-01

    Full Text Available The losses in the power systems should be low as possible as. Saving energy instead of loses (kWh in power utilities can supply much more energy to the consumers. The lower losses the more energy is saved and thus the power system becomes more economical. In recent years, the increasing number of applications and power ratings of the devices which have nonlinear voltage-current characteristics cause voltage waveform distortion and additional losses. While evaluating losses considering harmonics will provide more contribution to obtain more accurate results. In this study, Artificial Neural Networks (ANN method has been presented to predict the harmonic losses in unbalanced power systems by using the data from balanced power system with nonlinear loads.

  14. Effects of Strength Training Using Unstable Surfaces on Strength, Power and Balance Performance Across the Lifespan: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Behm, David G; Muehlbauer, Thomas; Kibele, Armin; Granacher, Urs

    2015-12-01

    The effectiveness of strength training on unstable surfaces (STU) versus stable surfaces (STS) or a control condition (CON; i.e., no training or regular training only) for strength, power and balance performance across the lifespan has not yet been investigated in a systematic review and meta-analysis. The aims of this systematic review and meta-analysis were to determine the general effects of STU versus STS or CON on muscle strength, power and balance in healthy individuals across the lifespan and to investigate whether performance changes following STU are age specific. A computerized systematic literature search was performed in the electronic databases PubMed and Web of Science from January 1984 up to February 2015. Initially, 209 articles were identified for review. Only controlled trials were included if they investigated STU in healthy individuals and tested at least one measure of maximal strength, strength endurance, muscle power, or static/dynamic balance. In total, 22 studies met the inclusion criteria. The included studies were coded for the following criteria: age, sex, training status, training modality, exercise and test modality. Effect size measures included within-subject standardized mean differences (SMDw) and weighted between-subject standardized mean differences (SMDb). Heterogeneity between studies was assessed using I2 and χ2 statistics. The methodological quality of each study was assessed using the Physiotherapy Evidence Database (PEDro) Scale. Our search failed to identify studies that examined the effects of STU versus STS or CON in children and middle-aged adults. However, four studies were identified that investigated the effects of STU versus CON or STS in adolescents, 15 studies were identified in young adults and three studies were identified in old adults. Compared with CON, STU produced medium effects on maximal strength in young adults and no effects to medium effects in old adults. In addition, large effects were detected on

  15. Re-insurance in the Swiss health insurance market: Fit, power, and balance.

    Science.gov (United States)

    Schmid, Christian P R; Beck, Konstantin

    2016-07-01

    Risk equalization mechanisms mitigate insurers' incentives to practice risk selection. On the other hand, incentives to limit healthcare spending can be distorted by risk equalization, particularly when risk equalization payments depend on realized costs instead of expected costs. In addition, cost based risk equalization mechanisms may incentivize health insurers to distort the allocation of resources among different services. The incentives to practice risk selection, to limit healthcare spending, and to distort the allocation of resources can be measured by fit, power, and balance, respectively. We apply these three measures to evaluate the risk adjustment mechanism in Switzerland. Our results suggest that it performs very well in terms of power but rather poorly in terms of fit. The latter indicates that risk selection might be a severe problem. We show that re-insurance can reduce this problem while power remains on a high level. In addition, we provide evidence that the Swiss risk equalization mechanism does not lead to imbalances across different services. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Power systems balancing with high penetration renewables: The potential of demand response in Hawaii

    International Nuclear Information System (INIS)

    Critz, D. Karl; Busche, Sarah; Connors, Stephen

    2013-01-01

    Highlights: • Demand response for Oahu results in system cost savings. • Demand response improves thermal power plant operations. • Increased use of wind generation possible with demand response. • WILMAR model used to simulate various levels and prices of demand response. - Abstract: The State of Hawaii’s Clean Energy policies call for 40% of the state’s electricity to be supplied by renewable sources by 2030. A recent study focusing on the island of Oahu showed that meeting large amounts of the island’s electricity needs with wind and solar introduced significant operational challenges, especially when renewable generation varies from forecasts. This paper focuses on the potential of demand response in balancing supply and demand on an hourly basis. Using the WILMAR model, various levels and prices of demand response were simulated. Results indicate that demand response has the potential to smooth overall power system operation, with production cost savings arising from both improved thermal power plant operations and increased wind production. Demand response program design and cost structure is then discussed drawing from industry experience in direct load control programs

  17. Comparative analysis of hourly and dynamic power balancing models for validating future energy scenarios

    DEFF Research Database (Denmark)

    Pillai, Jayakrishnan R.; Heussen, Kai; Østergaard, Poul Alberg

    2011-01-01

    Energy system analyses on the basis of fast and simple tools have proven particularly useful for interdisciplinary planning projects with frequent iterations and re-evaluation of alternative scenarios. As such, the tool “EnergyPLAN” is used for hourly balanced and spatially aggregate annual......, the model is verified on the basis of the existing energy mix on Bornholm as an islanded energy system. Future energy scenarios for the year 2030 are analysed to study a feasible technology mix for a higher share of wind power. Finally, the results of the hourly simulations are compared to dynamic frequency...... simulations incorporating the Vehicle-to-grid technology. The results indicate how the EnergyPLAN model may be improved in terms of intra-hour variability, stability and ancillary services to achieve a better reflection of energy and power capacity requirements....

  18. Lower limb muscle moments and power during recovery from forward loss of balance in male and female single and multiple steppers.

    Science.gov (United States)

    Carty, Christopher P; Cronin, Neil J; Lichtwark, Glen A; Mills, Peter M; Barrett, Rod S

    2012-12-01

    Studying recovery responses to loss of balance may help to explain why older adults are susceptible to falls. The purpose of the present study was to assess whether male and female older adults, that use a single or multiple step recovery strategy, differ in the proportion of lower limb strength used and power produced during the stepping phase of balance recovery. Eighty-four community-dwelling older adults (47 men, 37 women) participated in the study. Isometric strength of the ankle, knee and hip joint flexors and extensors was assessed using a dynamometer. Loss of balance was induced by releasing participants from a static forward lean (4 trials at each of 3 forward lean angles). Participants were instructed to recover with a single step and were subsequently classified as using a single or multiple step recovery strategy for each trial. (1) Females were weaker than males and the proportion of females that were able to recover with a single step were lower than for males at each lean magnitude. (2) Multiple compared to single steppers used a significantly higher proportion of their hip extension strength and produced less knee and ankle joint peak power during stepping, at the intermediate lean angle. Strength deficits in female compared to male participants may explain why a lower proportion of female participants were able to recover with a single step. The inability to generate sufficient power in the stepping limb appears to be a limiting factor in single step recovery from forward loss of balance. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  19. Balancing beyond the horizon?

    DEFF Research Database (Denmark)

    Kluth, Michael Friederich; Pilegaard, Jess

    2011-01-01

    The present article seeks to make sense of recent European Union (EU) naval capability changes by applying neo-realist theory to the EU as a collective actor in the global balance of power. The paper compares two different strands of neorealist theory by deducing key predictions about the expecte......-term balancing strategy aimed at bolstering the autonomy and international influence of the Union vis-a`-vis other major powers, including the USA....

  20. Getting the balance right

    International Nuclear Information System (INIS)

    1987-01-01

    This 8 page leaflet is published by the Nuclear Electricity Information Group (NEIG) which is made up of eight different bodies working within the nuclear industry. It aims to present a balanced outline of the facts needed to form an opinion about energy policy in the UK. It looks at the price of electricity, other sources of electricity, (oil and coal, solar power, wind power, water power), safety in the nuclear industry, nuclear waste disposal and risks from radiation. The NEIG is in favour of a balanced energy programme with nuclear energy being only a part of the overall scheme. (U.K.)

  1. [Effects of a training of power and balance on the use of mechanical restraint among in-patients with dementia].

    Science.gov (United States)

    Steinert, Tilman; Bohnet, Ulrich; Flammer, Erich; Lüchtenberg, Dietmar; Eisele, Frank

    2009-09-01

    Patients with dementia are most frequently affected by mechanical restraint in psychiatric hospitals, most frequently due to falls. There is evidence for beneficial effects of a training of power and balance on the frequency of falls in residential homes. An adapted training of power and balance was developed by specialists of training in sports. In 2007, 159 patients with dementia were trained. The frequency and duration of mechanical restraint was compared with a control group of a different hospital (n = 217) and the patients treated in the year before (n = 164). The percentage of patients with mechanical restraint and the mean duration of restraint per admission were significantly lower than in the control group. However, only a non-significant reduction could be achieved in comparison with the patients treated in the year before without an increase of falls. A considerable reduction of the use of mechanical restraint in patients with dementia is feasible. An unequivocal association with the training could not be confirmed due to other influencing factors.

  2. Forecasted balance sheet of the power supply and demand equilibrium in France. 2007 issue

    International Nuclear Information System (INIS)

    2007-01-01

    Conformably with the law from February 10, 2000, RTE, the French power transportation network is liable for establishing, at least every two year, a pluri-annual forecasted balance sheet of the power supply and demand equilibrium. Its aim is to identify the unbalance risks between the power consumption and the available generation means. To perform this technical expertise, RTE establishes some forecasts of domestic power consumption which are compared to the known perspectives of evolution of the production means. Two main changes have been taken into consideration in this analysis: the improvement of the energy efficiency, and the decay of power consumption in the big industry. Therefore, the new reference scenario indicates a consumption growth of 1.3% per year up to 2010 and 1% only for the next decade, i.e. 534 TWh of annual power consumption for 2020. On the offer side, several projects of new production means (mainly gas combined cycles) have been accepted during the last two years which represent more than 13000 MW of additional power. On the other hand, the decommissioning of several old fossil fuel power plants is foreseen for 2015 and represent 4400 MW. The offer based on decentralized production means is changing too, mainly thanks to the development of the wind power industry. In order to reach the supply-demand equilibrium, an acceptability threshold for failure duration has been defined by the public authorities and is limited to 3 hours per year. According to the reference scenario, the security of supplies in France seems to be reasonably assured for the next five years to come. A complement of 10500 MW will be necessary to meet the demand foreseen for 2020. (J.S.)

  3. Energy balance and efficiency of power stations with a pulsed Tokamak reactor

    International Nuclear Information System (INIS)

    Davenport, P.A.; Mitchell, J.T.D.; Darvas, J.; Foerster, S.; Sack, B.

    1976-06-01

    The energy balance of a fusion power station based on the TOKAMAK concept is examined with the aid of a model comprising three distinct elements: the reactor, the energy converter and the reactor operation equipment. The efficiency of each element is expressed in terms of the various energy flows and the product of these efficiencies gives the net station efficiency. The analysis takes account of pulsed operation and has general applicability. Numerical values for the net station efficiency are derived from detailed estimates of the energy flows for a TOKAMAK reactor and its auxiliary equipment operating with advanced energy converters. The derivation of these estimates is given in eleven appendices. The calculated station efficiencies span ranges similar to those quoted for the current generation of fission reactors, though lower than those predicted for HTGR and LMFBR stations. Credible parameter domains for pulsed TOKAMAK operation are firmly delineated and factors inimical to improved performance are indicated. It is concluded that the net thermal efficiency of a TOKAMAK reactor power station based on present designs and using advanced thermal converters will be approximately 0.3 and is unlikely to exceed 0.33. (orig.) [de

  4. [Balance of power in hospitals].

    Science.gov (United States)

    Lameyer, A

    2000-08-01

    It is known that there is a large extent of working dissatisfaction within some professional groups of the health service system. Especially in the hospital sector, many "struggles for power" take place. Unfortunately, these struggles are often only examined with regard to individual points of view without considering the system-oriented background. The following text will reflect the discussion in social sciences as to the distribution of power within the health service system. The double meaning of the distribution of power will be explained and, by means of decisive phenomenons, the development of cost and efficiency structures on the one hand as well as the development of health political processes in decision-making on the other hand will be described. In the section "The Hospital in the 20th Century", the structures that still can be widely found nowadays will be specified and examined as to aspects in behavioural sciences. Finally, as a logical consequence, an urgently needed reorientation from administration towards management will be pointed out.

  5. Balancing the roles of humans and machines in power plant control

    International Nuclear Information System (INIS)

    Lipsett, J.J.

    1989-05-01

    A number of factors are leading to a re-examination of the balance between the roles of the operators and the machine in controlling nuclear power plants. Some of these factors are: the advent of new and advanced computer technologies; increased plant complexity, placing heavy workloads and stress on the control room operator; and increasing concerns about the role of human reliability in industrial mishaps. In light of the changing control aspects, we examine the meaning of automation, we discuss a proposed model of the control process, the concept of control within a few defined reactor states, a decision-making sequence; and we identify some possible problem areas in implementing new control technologies. Significant benefits should come from the new control methods and these opportunities should be exploited as soon as prudence allows, taking great care that the safety of the plants is improved

  6. Assessment of load of beam-balanced pumping units by electric motor power indicators

    Directory of Open Access Journals (Sweden)

    Д. И. Шишлянников

    2017-10-01

    Full Text Available The results of experimental studies on the loading of beam-balanced pumping units (BP of sucker rod- pumping equipment (SRPE are presented. It is noted that the key factor that has the most significant effect causing the SRPE failure is the balance of the beam pumping unit, which determines the amount of specific energy consumption for the rise of reservoir fluid and the level of dynamic loads on the machine units. The urgency of using software-recording systems for estimating the loading of units of oil field pumping installations is substantiated. The principle of operation and design of the «AKD-SK» software recording system is described. The prospects of using this method for controlling the performance parameters and evaluating the technical state of the sicker rod-pumping units is proved on the basis of an analysis of the magnitude and nature of the changes in the loads of drive motors determined by the registration of the instantaneous values of the consumed power. The main provisions of the methodology for analyzing the watt-meters of drive motors of the sucker rod-pumping units are outlined. The nature of the manifestation of the main defects of submersible pumps and beam-balanced pumping units is described. The results of pilot-industrial tests of the beam-balanced pumping units equipped with advanced permanent magnet motors and intelligent control stations are presented. It is proved that the use of permanent magnet motors allows to reduce the specific energy consumption for the rise of reservoir fluid, which increases the efficiency of the SRPE.However, the presence of transient processes and generator operating modes of the permanent magnet motors results in the occurrence of significant dynamic loads, which, due to the rigid fixing of the rotor of magnet motor on the reducer shaft, negatively affect the life of the gearbox bearings. It has been shown that the lack of its own bearings in the tested motors causes a high probability

  7. Power Control and Monitoring Requirements for Thermal Vacuum/Thermal Balance Testing of the MAP Observatory

    Science.gov (United States)

    Johnson, Chris; Hinkle, R. Kenneth (Technical Monitor)

    2002-01-01

    The specific heater control requirements for the thermal vacuum and thermal balance testing of the Microwave Anisotropy Probe (MAP) Observatory at the Goddard Space Flight Center (GSFC) in Greenbelt, Maryland are described. The testing was conducted in the 10m wide x 18.3m high Space Environment Simulator (SES) Thermal Vacuum Facility. The MAP thermal testing required accurate quantification of spacecraft and fixture power levels while minimizing heater electrical emissions. The special requirements of the MAP test necessitated construction of five (5) new heater racks.

  8. Optimal Power Allocation for Downstream xDSL With Per-Modem Total Power Constraints: Broadcast Channel Optimal Spectrum Balancing (BC-OSB)

    Science.gov (United States)

    Le Nir, Vincent; Moonen, Marc; Verlinden, Jan; Guenach, Mamoun

    2009-02-01

    Recently, the duality between Multiple Input Multiple Output (MIMO) Multiple Access Channels (MAC) and MIMO Broadcast Channels (BC) has been established under a total power constraint. The same set of rates for MAC can be achieved in BC exploiting the MAC-BC duality formulas while preserving the total power constraint. In this paper, we describe the BC optimal power allo- cation applying this duality in a downstream x-Digital Subscriber Lines (xDSL) context under a total power constraint for all modems over all tones. Then, a new algorithm called BC-Optimal Spectrum Balancing (BC-OSB) is devised for a more realistic power allocation under per-modem total power constraints. The capacity region of the primal BC problem under per-modem total power constraints is found by the dual optimization problem for the BC under per-modem total power constraints which can be rewritten as a dual optimization problem in the MAC by means of a precoder matrix based on the Lagrange multipliers. We show that the duality gap between the two problems is zero. The multi-user power allocation problem has been solved for interference channels and MAC using the OSB algorithm. In this paper we solve the problem of multi-user power allocation for the BC case using the OSB algorithm as well and we derive a computational efficient algorithm that will be referred to as BC-OSB. Simulation results are provided for two VDSL2 scenarios: the first one with Differential-Mode (DM) transmission only and the second one with both DM and Phantom- Mode (PM) transmissions.

  9. First Aspect of Conventional Power System Assessment for High Wind Power Plants Penetration

    Directory of Open Access Journals (Sweden)

    A Merzic

    2012-11-01

    Full Text Available Most power systems in underdeveloped and developing countries are based on conventional power plants, mainly "slow-response" thermal power plants and a certain number of hydro power plants; characterized by inflexible generating portfolios and traditionally designed to meet own electricity needs. Taking into account operational capabilities of conventional power systems, their development planning will face problems with integration of notable amounts of installed capacities in wind power plants (WPP. This is what highlights the purpose of this work and in that sense, here, possible variations of simulated output power from WPP in the 10 minute and hourly time interval, which need to be balanced, are investigated, presented and discussed. Comparative calculations for the amount of installed power in WPP that can be integrated into a certain power system, according to available secondary balancing power amounts, in case of concentrated and dispersed future WPP are given. The stated has been done using a part of the power system of Bosnia and Herzegovina. In the considered example, by planned geographically distributed WPP construction, even up to cca. 74% more in installed power of WPP can be integrated into the power system than in case of geographically concentrated WPP construction, for the same available amount of (secondary balancing power. These calculations have shown a significant benefit of planned, geographically distributed WPP construction, as an important recommendation for the development planning of conventional power systems, with limited balancing options. Keywords: balancing reserves,  geographical dispersion, output power  variations

  10. The balancing mechanism. How to ensure the power production-consumption balance in a market opened to competition

    International Nuclear Information System (INIS)

    Harmnd, Y.; Nebas-Hamoudia, C.; Larripa, B.; Neupont, B.

    2005-01-01

    As electricity is a non-storable product in large quantities, generation and consumption have to be balanced at all times. In France, this balancing was historically solely supplied by EDF. Recent legislative changes have opened balancing supplies, thus creating competition. RTE, the electricity transmission system operator, has developed, in consultation with the main market players, the balancing mechanism. This enables available capacities to be merged in order to guarantee this balance. It operates like a permanent bidding system open to producers, industrial consumers and foreign players. Bids submitted by players are selected by RTE depending on the system requirements, taking into account merit order criterion and technical constraints. Prices issued from the balancing mechanism are used to provide a legitimate reference price for the settlement of imbalances between supplies and consumptions of the different electricity market players. Transparency, a crucial element of this mechanism, is ensured by a comprehensive system of open data publication. Since its launch, the balancing mechanism has proven its operational strength. (author)

  11. Radiocarbon Mass Balance for a Magnox Nuclear Power Station

    International Nuclear Information System (INIS)

    Metcalfe, M.P.; Mills, R.W.

    2016-01-01

    Nuclear power generation in the United Kingdom is based principally on graphite-moderated gas-cooled reactors. The mass of irradiated graphite associated with these reactors, including material from associated experimental, prototype and production reactors, exceeds 96,000 tonnes. One of the principal long-lived radionuclides produced during graphite irradiation is radiocarbon (C-14), which has a half-life of 5730 ± 40 years. Decommissioning and graphite waste management strategies must take account of this radionuclide. In order to identify appropriate options for addressing the potential hazard of C-14, it is important that the production processes are understood and the distributions and concentrations of C-14 are characterised. In fact, C-14 precursors and their activation processes are well-known. However, there is ongoing debate over the relative importance of different C-14 precursors, which will determine the location of C-14 within graphite components and hence its mobility/response to treatment. A generally held misconception concerning C-14 in irradiated graphite is that generic statements can be made about its precursors and their location. C-14 location and activities will depend upon the composition of the original manufactured graphite (raw materials, impurities), the chemical environment of the graphite during service and the irradiation history of the graphite. So, while there may be some similarities across, for example, carbon dioxide cooled graphite moderated designs (Magnox, AGR, UNGG), any informed assessment of a core’s C-14 inventory would require more-precise characterisation. The analysis presented here focuses on a UK Magnox reactor core, Reactor 1 at Wylfa Nuclear Power Station. The objective of the analysis is to present a full C-14 mass balance over a selected period of operation for which there are accurate C-14 discharge records. The analysis presented here provides the first assessment of the principal C-14 activation pathways

  12. The Shifting Global Power Balance Equations and the Emerging Real ‘New World Order’

    OpenAIRE

    Ovie-D’Leone, Alex Igho

    2010-01-01

    Expansion in globalization arising from increased interconnectivity and interdependence across the worldis causing a shift both in the focus of what now could determine the principal international powervariables and the criteria for power balancing calculus. One direct challenge to the status quo is theemergence on one hand of new state actors which are becoming more assertive, as well as some other newkey non-state actors now matching states seemingly one-on-one on the world stage in many sp...

  13. Participation of distributed generation in balance management

    NARCIS (Netherlands)

    Frunt, J.; Kechroud, A.; Kling, W.L.; Myrzik, J.M.A.

    2009-01-01

    Distributed generation is not yet considered to participate in balance management in power systems. Low marginal costs and poor predictability make them less attractive for this application. However, further integration of distributed generation will make participation in balance management a

  14. A Dynamic Model for Load Balancing in Cloud Infrastructure

    Directory of Open Access Journals (Sweden)

    Jitendra Bhagwandas Bhatia

    2015-08-01

    Full Text Available This paper analysis various challenges faced in optimizing computing resource utilization via load balancing and presents a platform-independent model for load balancing which targets high availability of resources, low SLA (Service Level agreement violations and saves power. To achieve this, incoming requests are monitored for sudden burst, a prediction model is employed to maintain high availability and a power-aware algorithm is applied for choosing a suitable physical node for a virtual host. The proposed dynamic load balancing model provides a way to conflicting goals of saving power and maintaining high resource availability.For anyone building a private, public or hybrid IaaS cloud infrastructure, load balancing of virtual hosts on a limited number of physical nodes, becomes a crucial aspect. This paper analysis various challenges faced in optimizing computing resource utilization via load balancing and presents a platform independent model for load balancing which targets high availability of resources, low SLA (Service Level agreement violations and saves power. To achieve this, incoming requests are monitored for sudden burst, prediction model is employed to maintain high availability and power aware algorithm is applied for choosing a suitable physical node for virtual host. The proposed dynamic load balancing model provides a way to conflicting goals of saving power and maintaining high resource availability.

  15. Large scale development of wind power. Consequences for the national grid and the need for load balancing; Storskalig utbyggnad av vindkraft. Konsekvenser foer stamnaetet och behovet av reglerkraft

    Energy Technology Data Exchange (ETDEWEB)

    2008-06-15

    Wind power is expected to growth rapidly in Sweden. The existing certificate system gives economic incentives for development of 17 TWh from renewable energy sources until 2016, compared to the 2002 level. The Swedish Energy Agency estimates that 9 TWh wind power will be built by 2020, given the present certificate system. However, a new planning goal of 30 TWh wind energy by 2020 has been proposed by the Agency. It is very important for Svenska Kraftnaet to follow the development in order to take the right actions to adapt the national grid to the increased share of wind power. The total increased need for balancing power is estimated to be: 1 400-1 800 MW for 10 TWh added wind power, and 4 300-5 300 MW for 30 TWh. About 15% of the increased balancing need must be assigned to automatically frequency regulating generation. The rest can be made up of sources that can be regulated on a minute- or hour-scale. The planned wind power risks to replace generation with regulating capacity, and it is important to continuously analyze if and how this happens, and which the consequences will be for the balancing capacity. The socio-economic effects for the national grid include increased investment cost and increased costs foe balancing and regulating. Massive expansion in North Sweden is the most costly alternative, with a capitalized cost estimated to 25 000 MSEK (about 4 000 MUSD) at an expansion of 30 TWh wind power. This can be compared to the estimated investment cost for the wind power expansion of 150 000 MSEK

  16. Is direct marketing a risk factor? Inaccurate forecasting of power generation from renewables raises the demand for balancing power; Risikofaktor Direktvermarktung? Durch ungenaue Prognosen bei der Einspeisung von gruenem Strom steigt der Bedarf an Regelleistung

    Energy Technology Data Exchange (ETDEWEB)

    Korn, Stefan

    2012-05-15

    Since the amendment of the EEG in January 2012, enormous amounts of electric power from renewable energy sources are marketed directly, i.e. outside the control of power supply grid owners and operators that formerly sold the electric power in the stock exchange. Inaccurate prognoses made by the direct marketers as well as their marketing strategies have increased the demand for balancing power and made critical situations in the power grid even more difficult.

  17. Can quantum coherent solar cells break detailed balance?

    International Nuclear Information System (INIS)

    Kirk, Alexander P.

    2015-01-01

    Carefully engineered coherent quantum states have been proposed as a design attribute that is hypothesized to enable solar photovoltaic cells to break the detailed balance (or radiative) limit of power conversion efficiency by possibly causing radiative recombination to be suppressed. However, in full compliance with the principles of statistical mechanics and the laws of thermodynamics, specially prepared coherent quantum states do not allow a solar photovoltaic cell—a quantum threshold energy conversion device—to exceed the detailed balance limit of power conversion efficiency. At the condition given by steady-state open circuit operation with zero nonradiative recombination, the photon absorption rate (or carrier photogeneration rate) must balance the photon emission rate (or carrier radiative recombination rate) thus ensuring that detailed balance prevails. Quantum state transitions, entropy-generating hot carrier relaxation, and photon absorption and emission rate balancing are employed holistically and self-consistently along with calculations of current density, voltage, and power conversion efficiency to explain why detailed balance may not be violated in solar photovoltaic cells

  18. 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

    , is provided by the hour-ahead power balancing model, i.e. Simulation power Balancing model (SimBa. The regulating power plan is prepared from day-ahead power production plan and hour-ahead wind power forecast. The wind power (forecasts and available) are provided by the Correlated Wind power fluctuations (Cor......Wind) model, where the wind turbine storm controllers are also implemented....

  19. A Power Balance Aware Wireless Charger Deployment Method for Complete Coverage in Wireless Rechargeable Sensor Networks

    Directory of Open Access Journals (Sweden)

    Tu-Liang Lin

    2016-08-01

    Full Text Available Traditional sensor nodes are usually battery powered, and the limited battery power constrains the overall lifespan of the sensors. Recently, wireless power transmission technology has been applied in wireless sensor networks (WSNs to transmit wireless power from the chargers to the sensor nodes and solve the limited battery power problem. The combination of wireless sensors and wireless chargers forms a new type of network called wireless rechargeable sensor networks (WRSNs. In this research, we focus on how to effectively deploy chargers to maximize the lifespan of a network. In WSNs, the sensor nodes near the sink consume more power than nodes far away from the sink because of frequent data forwarding. This important power unbalanced factor has not been considered, however, in previous charger deployment research. In this research, a power balance aware deployment (PBAD method is proposed to address the power unbalance in WRSNs and to design the charger deployment with maximum charging efficiency. The proposed deployment method is effectively aware of the existence of the sink node that would cause unbalanced power consumption in WRSNs. The simulation results show that the proposed PBAD algorithm performs better than other deployment methods, and fewer chargers are deployed as a result.

  20. An analysis of physician antitrust exemption legislation: adjusting the balance of power.

    Science.gov (United States)

    Hellinger, F J; Young, G J

    2001-07-04

    Current antitrust law restricts physicians from joining together to collectively negotiate. However, such activities may be approved by state laws under the so-called state action immunity doctrine and by federal legislation under an explicit antitrust exemption. In 1999, Texas became the first state to pass physician antitrust exemption legislation allowing physicians, under certain defined circumstances, to collectively negotiate fees with health plans. Last year, similar legislation was introduced in the US Congress, in 18 state legislatures, and in the District of Columbia. This legislation was passed only in the District of Columbia where its implementation was blocked by the city's financial control board. Nonetheless, legislation permitting physicians to collectively negotiate fees with managed care plans has been introduced in 10 state legislatures this year, and there is continued interest in introducing similar legislation in the US Congress. This analysis examines the basic features of this legislation and its potential impact on the balance of power between physicians and managed care plans.

  1. Effects of bioDensity Training and Power Plate Whole-Body Vibration on Strength, Balance, and Functional Independence in Older Adults.

    Science.gov (United States)

    Smith, Derek T; Judge, Stacey; Malone, Ashley; Moynes, Rebecca C; Conviser, Jason; Skinner, James S

    2016-01-01

    Reduced strength, balance, and functional independence diminish quality of life and increase health care costs. Sixty adults (82.2 ± 4.9 years) were randomized to a control or three 12-week intervention groups: bioDensity (bD); Power Plate (PP) whole-body vibration (WBV); or bD+PP. bD involved one weekly 5-s maximal contraction of four muscle groups. PP involved two 5-min WBV sessions. Primary outcomes were strength, balance, and Functional Independence Measure (FIM). No groups differed initially. Strength significantly increased 22-51% for three muscle groups in bD and bD+PP (P Balance significantly improved in PP and bD+PP but not in control or bD. bD, PP, and bD+PP differentially improved FIM self-care and mobility. Strength improvements from weekly 5-min sessions of bD may impart health/clinical benefits. Balance and leg strength improvements suggest WBV beneficially impacts fall risk and incidence. Improved FIM scores are encouraging and justify larger controlled trials on bD and bD+PP efficacy.

  2. Power Balance Modeling of Local Helicity Injection for Non-Solenoidal ST Startup

    Science.gov (United States)

    Weberski, J. D.; Barr, J. L.; Bongard, M. W.; Fonck, R. J.; Perry, J. M.; Reusch, J. A.

    2017-10-01

    A zero-dimensional power balance model for predicting Ip(t) for Local Helicity Injection (LHI) discharges has been used to interpret experimental results from recent experimental campaigns using high-field-side (HFS) helicity injection. This model quantifies LHI's effective drive (Veff) through helicity balance while enforcing the Taylor relaxation current limit and tracking inductive effects to determine Ip(t) . Recent analysis of HFS LHI discharges indicate LHI is the dominant source of drive and provides Veff up to 1.3 V while geometric effects and inductive drive provide < 0.1 V throughout much of the discharge. In contrast to previous analysis of low-field-side (LFS) LHI discharges, which were driven by Veff = 0.3 V and 2.0 V from geometric effects and inductive drive. A significant remaining uncertainty in the model is the resistive dissipation of LHI discharges. This requires greater understanding of LHI confinement scaling and impurity content, which are currently under investigation. However, the model and experimental Ip(t) exhibit good agreement for parameters consistent with previous experimental findings. Extrapolation of plasma parameters and shaping from recent experiments allow for the model to project the performance of LHI systems. These projections indicate Ip 0.3 MA can be accessed on Pegasus via HFS LHI through changes to injector geometry to provide more Veff. This regime can be accessed via a LFS system by increasing the Taylor relaxation current limit early in the discharge. Work supported by US DOE Grants DE-FG02-96ER54375 and DE-SC0006928.

  3. Power balance in an Ohmically heated fusion reactor

    International Nuclear Information System (INIS)

    Christiansen, J.P.; Roberts, K.V.

    1982-01-01

    A simplified power-balance equation (zero-dimensional model) is used to study the performance of an Ohmically heated fusion reactor with emphasis on a pulsed reversed-field pinch concept (RFP). The energy confinement time tausub(E) is treated as an adjustable function, and empirical tokamak scaling laws are employed in the numerical estimates, which are supplemented by 1-D ATHENE code calculations. The known heating rates and energy losses are represented by the net energy replacement time tausub(W), which is exhibited as a surface in density (n) and temperature (T) space with a saddle point (nsub(*), Tsub(*)), the optimum ignition point. It is concluded that i) ignition by Ohmic heating is more practicable for the RFP reactor than for a tokamak reactor with the same tausub(E), (ii) if at fixed current the minor radius can be reduced or at fixed minor radius the current can be increased, then it is found that Ohmic ignition becomes more likely when present tokamak scaling laws are used. More definitive estimates require, however, a knowledge of tausub(E), which can only be obtained by establishing a reliable set of experimental RFP scaling laws and, in particular, by extending RFP experiments closer to the reactor regime. (author)

  4. Balancing Power Absorption and Fatigue Loads in Irregular Waves for an Oscillating Surge Wave Energy Converter: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Tom, Nathan M.; Yu, Yi-Hsiang; Wright, Alan D.; Lawson, Michael

    2016-06-01

    The aim of this paper is to describe how to control the power-to-load ratio of a novel wave energy converter (WEC) in irregular waves. The novel WEC that is being developed at the National Renewable Energy Laboratory combines an oscillating surge wave energy converter (OSWEC) with control surfaces as part of the structure; however, this work only considers one fixed geometric configuration. This work extends the optimal control problem so as to not solely maximize the time-averaged power, but to also consider the power-take-off (PTO) torque and foundation forces that arise because of WEC motion. The objective function of the controller will include competing terms that force the controller to balance power capture with structural loading. Separate penalty weights were placed on the surge-foundation force and PTO torque magnitude, which allows the controller to be tuned to emphasize either power absorption or load shedding. Results of this study found that, with proper selection of penalty weights, gains in time-averaged power would exceed the gains in structural loading while minimizing the reactive power requirement.

  5. A best practice fall prevention exercise program to improve balance, strength / power, and psychosocial health in older adults: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Gschwind, Yves J; Kressig, Reto W; Lacroix, Andre; Muehlbauer, Thomas; Pfenninger, Barbara; Granacher, Urs

    2013-10-09

    With increasing age neuromuscular deficits (e.g., sarcopenia) may result in impaired physical performance and an increased risk for falls. Prominent intrinsic fall-risk factors are age-related decreases in balance and strength / power performance as well as cognitive decline. Additional studies are needed to develop specifically tailored exercise programs for older adults that can easily be implemented into clinical practice. Thus, the objective of the present trial is to assess the effects of a fall prevention program that was developed by an interdisciplinary expert panel on measures of balance, strength / power, body composition, cognition, psychosocial well-being, and falls self-efficacy in healthy older adults. Additionally, the time-related effects of detraining are tested. Healthy old people (n = 54) between the age of 65 to 80 years will participate in this trial. The testing protocol comprises tests for the assessment of static / dynamic steady-state balance (i.e., Sharpened Romberg Test, instrumented gait analysis), proactive balance (i.e., Functional Reach Test; Timed Up and Go Test), reactive balance (i.e., perturbation test during bipedal stance; Push and Release Test), strength (i.e., hand grip strength test; Chair Stand Test), and power (i.e., Stair Climb Power Test; countermovement jump). Further, body composition will be analysed using a bioelectrical impedance analysis system. In addition, questionnaires for the assessment of psychosocial (i.e., World Health Organisation Quality of Life Assessment-Bref), cognitive (i.e., Mini Mental State Examination), and fall risk determinants (i.e., Fall Efficacy Scale - International) will be included in the study protocol. Participants will be randomized into two intervention groups or the control / waiting group. After baseline measures, participants in the intervention groups will conduct a 12-week balance and strength / power exercise intervention 3 times per week, with each training session lasting 30 min

  6. Predictive assessment of the Ukrainian power industry fuel balance structure progress

    Directory of Open Access Journals (Sweden)

    Alexander P. Voinov

    2014-12-01

    Full Text Available The existing structure of the fuel balance in Ukraine does largely determine high prices of such energy products as the electricity and the heat. The main reason lies in the fact that approximately 40% of the fuel balance represents the expensive imported liquid and gaseous fuels. Of course, such balance structure significantly affects the energy security of Ukraine. The article analyzes the three main directions of this situation possible normalization: replacing the imported gas with relatively inexpensive domestic coal burned at boilers and innovative coal-fired burner systems, especially in the low-temperature boilers with fluidized bed furnaces; replacement of imported fuel with respectively cheap pyrolysis gas obtained from the domestic low-grade brown coal; organization of domestic production of shale gas, which industrial production is scheduled for 2020. These promising directions of the national energetics’ fuel balance development can be considered as a priority part of the national tasks of increasing the country’s energy independence.

  7. General framework for real-time implementation of balancing services market outcome

    NARCIS (Netherlands)

    Virag, A.; Jokic, A.; Bosch, van den P.P.J.

    2012-01-01

    Load frequency control (LFC) is widely used for real-time balancing connected power systems. With the deregulation of power system markets, there is a necessity for adapting the current LFC to support market-based operation. In this paper we propose a general balancing tool which covers both,

  8. Central receiver solar thermal power system, Phase 1. CDRL item 2. Pilot plant preliminary design report. Volume VI. Electrical power generation and master control subsystems and balance of plant

    Energy Technology Data Exchange (ETDEWEB)

    Hallet, Jr., R. W.; Gervais, R. L.

    1977-10-01

    The requirements, performance, and subsystem configuration for both the Commercial and Pilot Plant electrical power generation subsystems (EPGS) and balance of plants are presented. The EPGS for both the Commercial Plant and Pilot Plant make use of conventional, proven equipment consistent with good power plant design practices in order to minimize risk and maximize reliability. The basic EPGS cycle selected is a regenerative cycle that uses a single automatic admission, condensing, tandem-compound double-flow turbine. Specifications, performance data, drawings, and schematics are included. (WHK)

  9. REVISITING EUROPE’S GEOPOLITICAL LANDSCAPE AFTER THE UKRAINE CRISIS: AMERICA’S BALANCE OF POWER STRATEGY

    Directory of Open Access Journals (Sweden)

    Sotiris Serbos

    2018-01-01

    Full Text Available The unveiling of the economic crisis in Europe foregrounds the resurgence of geopolitics in transatlantic foreign policy analysis. With the EU project still at risk, a fragmented Europe allows Russia to gain ground and challenge the European power balance at large. We argue that the U.S. will seriously try to avert such a path and even loss of commitment towards further EU integration. In order to keep Europe united, we stress that the U.S. can exploit the Ukraine crisis by compelling Europe’s pivotal player (Germany towards a European leadership fully committed to EU integration as its ideal option.

  10. Radiocarbon mass balance for a Magnox nuclear power station

    International Nuclear Information System (INIS)

    Metcalfe, M.P.; Mills, R.W.

    2015-01-01

    Highlights: • First comprehensive assessment of C-14 arisings in a Magnox nuclear power station. • C-14 production in graphite and coolant gas quantified by activation modelling. • Principal C-14 production pathway is via C-13 with a small contribution from N-14. • C-14 mass balance model provides a basis for analyses on other reactors. - Abstract: Nuclear power generation in the United Kingdom is based principally on graphite-moderated gas-cooled reactors. The mass of irradiated graphite associated with these reactors, including material from associated experimental, prototype and plutonium production reactors, exceeds 96,000 tonnes. One of the principal long-lived radionuclides produced during graphite irradiation is radiocarbon (C-14). Its potential as a hazard must be taken into account in decommissioning and graphite waste management strategies. While C-14 production processes are well-understood, radionuclide distributions and concentrations need to be characterised. A common misconception is that generic statements can be made about C-14 precursors and their location. In fact, the composition of the original manufactured material, the chemical environment of the graphite during service and its irradiation history will all influence C-14 levels. The analysis presented here provides the first assessment of the principal C-14 activation pathways for a UK Magnox reactor. Activation modelling has been used to predict C-14 production rates in both the graphite core and the carbon dioxide coolant over a selected period of operation and the results compared with monitored site C-14 discharges. Principal activation routes have been identified, which should inform future graphite waste management strategies relating to radiocarbon

  11. Revised sequence components power system models for unbalanced power system studies

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Akher, M. [Tunku Abdul Rahman Univ., Kuala Lumpur (Malaysia); Nor, K.-M. [Univ. of Technology Malaysia, Johor (Malaysia); Rashid, A.H.A. [Univ. of Malaya, Kuala Lumpur (Malaysia)

    2007-07-01

    The principle method of analysis using positive, negative, and zero-sequence networks has been used to examine the balanced power system under both balanced and unbalanced loading conditions. The significant advantage of the sequence networks is that the sequence networks become entirely uncoupled in the case of balanced three-phase power systems. The uncoupled sequence networks then can be solved in independent way such as in fault calculation programs. However, the hypothesis of balanced power systems cannot be considered in many cases due to untransposed transmission lines; multiphase line segments in a distribution power system; or transformer phase shifts which cannot be incorporated in the existing models. A revised sequence decoupled power system models for analyzing unbalanced power systems based on symmetrical networks was presented in this paper. These models included synchronous machines, transformers, transmission lines, and voltage regulators. The models were derived from their counterpart's models in phase coordinates frame of reference. In these models, the three sequence networks were fully decoupled with a three-phase coordinates features such as transformer phase shifts and transmission line coupling. The proposed models were used to develop an unbalanced power-flow program for analyzing both balanced and unbalanced networks. The power flow solution was identical to results obtained from a full phase coordinate three-phase power-flow program. 11 refs., 3 tabs.

  12. Wave power balance in resonant dissipative media with spatial and temporal dispersion

    International Nuclear Information System (INIS)

    Tokman, M.D.; Gavrilova, M.A.; Westerhof, E. . www.rijnh.nl

    2003-01-01

    A power balance for waves in resonant dissipative media is formulated, which generalizes well-known expressions for dielectric wave energy density, wave energy flux, and dissipated power density. The identification of the different terms with wave energy density and flux remains only phenomenological. The result is better viewed as an equation for the evolution of wave intensity. In that form, its consequences are discussed in particular in relation to anomalous dispersion. A discrimination is made between boundary and initial value problems. For boundary value problems, anomalous dispersion is shown not to lead to unphysical results. In contrast, for initial value problems the solution for the evolution of wave intensity is shown to be at fault in the case of anomalous dispersion. Further illustration is provided by consideration of wave dispersion in a medium of charged harmonic oscillators and of ordinary-mode dispersion in plasma. Both are characterized by anomalous dispersion and show marked differences in the solutions of the dispersion relation solved either for complex wave vector at real frequency, k(ω) (applicable to boundary value problems), or for complex frequency at real wave vector ω(k) (applicable to initial value problems). (author)

  13. Balancing the Power-to-Load Ratio for a Novel Variable Geometry Wave Energy Converter with Nonideal Power Take-Off in Regular Waves: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Tom, Nathan M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Yu, Yi-Hsiang [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wright, Alan D [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-28

    This work attempts to balance power absorption against structural loading for a novel variable geometry wave energy converter. The variable geometry consists of four identical flaps that will be opened in ascending order starting with the flap closest to the seafloor and moving to the free surface. The influence of a pitch motion constraint on power absorption when utilizing a nonideal power take-off (PTO) is examined and found to reduce the losses associated with bidirectional energy flow. The power-to-load ratio is evaluated using pseudo-spectral control to determine the optimum PTO torque based on a multiterm objective function. The pseudo-spectral optimal control problem is extended to include load metrics in the objective function, which may now consist of competing terms. Separate penalty weights are attached to the surge-foundation force and PTO control torque to tune the optimizer performance to emphasize either power absorption or load shedding. PTO efficiency is not included in the objective function, but the penalty weights are utilized to limit the force and torque amplitudes, thereby reducing losses associated with bidirectional energy flow. Results from pseudo-spectral control demonstrate that shedding a portion of the available wave energy can provide greater reductions in structural loads and reactive power.

  14. Tokamak plasma power balance calculation code (TPC code) outline and operation manual

    International Nuclear Information System (INIS)

    Fujieda, Hirobumi; Murakami, Yoshiki; Sugihara, Masayoshi.

    1992-11-01

    This report is a detailed description on the TPC code, that calculates the power balance of a tokamak plasma according to the ITER guidelines. The TPC code works on a personal computer (Macintosh or J-3100/ IBM-PC). Using input data such as the plasma shape, toroidal magnetic field, plasma current, electron temperature, electron density, impurities and heating power, TPC code can determine the operation point of the fusion reactor (Ion temperature is assumed to be equal to the electron temperature). Supplied flux (Volt · sec) and burn time are also estimated by coil design parameters. Calculated energy confinement time is compared with various L-mode scaling laws and the confinement enhancement factor (H-factor) is evaluated. Divertor heat load is predicted by using simple scaling models (constant-χ, Bohm-type-χ and JT-60U empirical scaling models). Frequently used data can be stored in a 'device file' and used as the default values. TPC code can generate 2-D mesh data and the POPCON plot is drawn by a contour line plotting program (CONPLT). The operation manual about CONPLT code is also described. (author)

  15. Strength and Power Training Effects on Lower Limb Force, Functional Capacity, and Static and Dynamic Balance in Older Female Adults.

    Science.gov (United States)

    Lopes, Paula Born; Pereira, Gleber; Lodovico, Angélica; Bento, Paulo C B; Rodacki, André L F

    2016-03-03

    It has been proposed that muscle power is more effective to prevent falls than muscle force production capacity, as rapid reactions are required to allow the postural control. This study aimed to compare the effects of strength and power training on lower limb force, functional capacity, and static and dynamic balance in older female adults. Thirty-seven volunteered healthy women had been allocated into the strength-training group (n = 14; 69 ± 7.3 years, 155 ± 5.6 cm, 72 ± 9.7 kg), the power-training group (n = 12; 67 ± 7.4 years, 153 ± 5.5 cm, 67.2 ± 7 kg), and control group (n = 11; 65 ± 3.1 years, 154 ± 5.6 cm, 70.9 ± 3 kg). After 12 weeks of training, the strength-training and power-training groups increased significantly maximum dynamic strength (29% and 27%), isometric strength (26% and 37%), and step total time (13% and 14%, dynamic balance), respectively. However, only the power-training group increased the rate of torque development (55%) and the functional capacity in 30-second chair stand (22%) and in time up and go tests (-10%). Empirically, power training may reduce the risk of injuries due to lower loads compared to strength training, and consequently, the physical effort demand during the training session is lower. Therefore, power training should be recommended as attractive training stimuli to improve lower limb force, functional capacity, and postural control of older female adults.

  16. Harmonising the balancing market Issues to be considered

    Energy Technology Data Exchange (ETDEWEB)

    2010-07-15

    One of the work streams established in NordREG Work Programme for 2009 is related to the Nordic balancing power market and balance management. One of the tasks is to follow up the implementation of the common balance management according to what was described above, the other task is related to the efficient functioning of the Nordic balancing power market. While it has been noted that the Nordic wholesale market functions well, there is an expectation that further harmonization of the Nordic balancing power market would improve the efficiency of the market and form the basis for further integration with adjacent markets in the area of balancing services. Therefore NordREG has taken on to investigate in which areas further harmonization can be expected to be cost-efficient and contribute to a better functioning market and how this harmonized market could be monitored. The task according to the work programme is: 'In its initial work regarding Nordic balancing, NordREG noted that the common Nordic list for bids in regulation power works fairly well. However, there seems to be scope for increased efficiency. This might be attained by identifying important differences in the framework between countries as well as proposing a genuine Nordic harmonisation. It is important initially to discuss to what degree harmonisation is necessary in order to improve the efficient functioning of the market. 'In approaching these topics, NordREG has been discussing with the Nordic TSOs, where appropriate, and has made use of Nordel's publications on this topic. This report provides an overview of the current state of integration and harmonization of balancing in the Nordic region. The report also provides a summary of the harmonization measures that might be implemented in the future

  17. Control Structures for Smart Grid Balancing

    DEFF Research Database (Denmark)

    Juelsgaard, Morten; Totu, Luminita Cristiana; Shafiei, Seyed Ehsan

    2013-01-01

    This work addresses the problem of maintaining the balance between consumption and production in the electricity grid when volatile resources, such as wind and sun, account for a large percentage of the power generation. We present control structures for Smart Grid balancing services on three...

  18. Recent laser physics results on power balance and frequency conversion with the Phebus laser system

    International Nuclear Information System (INIS)

    Thiell, G.; Paye, J.; Graillot, H.; Mathieu, F.; Boscheron, A.; Reynier, F.; Estraillier, P.; Bruneau, J.L.

    1995-01-01

    The Phebus laser system has been mainly devoted to plasma physics experiments such as implosion and hydrodynamical instability studies since it was completed in 1985. But during the last two years, the three Phebus beamlines (2 main beams and a backlighter beam) are also utilized to perform some laser physics studies in view of the Megajoule laser project. The goal of the laser physics experiments conducted at the Phebus facility in 1994--1995 is to validate some design issues of the Megajoule Laser project concerning namely power balance and frequency conversion

  19. Analysis of the spontaneous variations in wind power and necessary continuous regulation of hydro-electric and thermal power, related to a future Swedish power system

    Energy Technology Data Exchange (ETDEWEB)

    Holm, J O; Lindstrom, P O

    1982-09-01

    Wind power is unlike conventional electric power generation, since the output fluctuates uncontrollably. These fluctuations must be balanced by controlled generation from other power sources. This will create new and interesting demands on the reserves in the power system. The short-term fluctuations have a low simultaneity factor and must be balanced by an automatic frequency control reserve. In Sweden, this consists of automatically controlled hydro-electric power. The report contains calculations of the amount by which the demand on reserves will increase when wind power is introduced.

  20. Balance of excitation and inhibition determines 1/f power spectrum in neuronal networks.

    Science.gov (United States)

    Lombardi, F; Herrmann, H J; de Arcangelis, L

    2017-04-01

    The 1/f-like decay observed in the power spectrum of electro-physiological signals, along with scale-free statistics of the so-called neuronal avalanches, constitutes evidence of criticality in neuronal systems. Recent in vitro studies have shown that avalanche dynamics at criticality corresponds to some specific balance of excitation and inhibition, thus suggesting that this is a basic feature of the critical state of neuronal networks. In particular, a lack of inhibition significantly alters the temporal structure of the spontaneous avalanche activity and leads to an anomalous abundance of large avalanches. Here, we study the relationship between network inhibition and the scaling exponent β of the power spectral density (PSD) of avalanche activity in a neuronal network model inspired in Self-Organized Criticality. We find that this scaling exponent depends on the percentage of inhibitory synapses and tends to the value β = 1 for a percentage of about 30%. More specifically, β is close to 2, namely, Brownian noise, for purely excitatory networks and decreases towards values in the interval [1, 1.4] as the percentage of inhibitory synapses ranges between 20% and 30%, in agreement with experimental findings. These results indicate that the level of inhibition affects the frequency spectrum of resting brain activity and suggest the analysis of the PSD scaling behavior as a possible tool to study pathological conditions.

  1. Characteristic evaluations of BWR uprate method based on heat balance shift concept

    International Nuclear Information System (INIS)

    Kitou, Kazuaki; Aoyama, Motoo; Shiina, Kouji; Sasaki, Hiroshi; Yoshikawa, Kazuhiro

    2007-01-01

    Reactor power uprate of nuclear power plants is an efficient plant operating method. Most BWR plants need the exchange of high pressure turbines when plant thermal power increases over 5% because main steam flow rate exceeds the limitation of inlet steam flow rate of a high pressure turbine. Therefore, the new power uprate method named heat balance shift power uprate method has been developed. This method decreases feedwater temperature with increasing plant thermal power not to increase main steam flower rate. This study clarified that the heat balance shift method could increase plant electric power up to 2.8% compared with conventional power uprate method without the exchange of a high pressure turbine. (author)

  2. Tests of stepping as indicators of mobility, balance, and fall risk in balance-impaired older adults.

    Science.gov (United States)

    Cho, Be-long; Scarpace, Diane; Alexander, Neil B

    2004-07-01

    To determine the relationships between two tests of stepping ability (the maximal step length (MSL) and rapid step test (RST)) and standard tests of standing balance, gait, mobility, and functional impairment in a group of at-risk older adults. Cross-sectional study. University-based laboratory. One hundred sixty-seven mildly balance-impaired older adults recruited for a balance-training and fall-reduction program (mean age 78, range 65-90). Measures of stepping maximally (MSL, the ability to maximally step out and return to the initial position) and rapidly (RST, the time taken to step out and return in multiple directions as fast as possible); standard measures of balance, gait, and mobility including timed tandem stance (TS), tandem walk (TW, both timing and errors), timed unipedal stance (US), timed up and go (TUG), performance oriented mobility assessment (POMA), and 6-minute walk (SMW); measures of leg strength (peak knee and ankle torque and power at slow and fast speeds); self-report measures of frequent falls (>2 per 12 months), disability (Established Population for Epidemiologic Studies of the Elderly (EPESE) physical function), and confidence to avoid falls (Activity-specific Balance Confidence (ABC) Scale). Spearman and Pearson correlation, intraclass correlation coefficient, logistic regression, and linear regression were used for data analysis. MSL consistently predicted a number of self-report and performance measures at least as well as other standard balance measures. MSL correlations with EPESE physical function, ABC, TUG, and POMA scores; SMW; and peak maximum knee and ankle torque and power were at least as high as those correlations seen with TS, TW, or US. MSL score was associated with the risk of being a frequent faller. In addition, the six MSL directions were highly correlated (up to 0.96), and any one of the leg directions yielded similar relationships with functional measures and a history of falls. Relationships between RST and these

  3. Energy balance in processes of transition radiation

    International Nuclear Information System (INIS)

    Vladimirov, S.V.; Tsytovich, V.N.

    1985-01-01

    The authors consider the transition radiation arising when a charged particle crosses an interface between two nonabsorbing media. It is shown that energy balance is observed under these circumstances. The fulfillment of energy balance in transition radiation for nonabsorbing media is rigorously demonstrated. This allows one to find the energy of the transition radiation from the change in the energy of the intrinsic field of the charge and the work of forces for volume waves, which in a number of cases of complicated configurations may prove to be considerably simpler than a direct calculation of the radiation power. For surface waves, a calculation of the work of forces enables one to determine the radiation power directly

  4. Direct energy balance based active disturbance rejection control for coal-fired power plant.

    Science.gov (United States)

    Sun, Li; Hua, Qingsong; Li, Donghai; Pan, Lei; Xue, Yali; Lee, Kwang Y

    2017-09-01

    The conventional direct energy balance (DEB) based PI control can fulfill the fundamental tracking requirements of the coal-fired power plant. However, it is challenging to deal with the cases when the coal quality variation is present. To this end, this paper introduces the active disturbance rejection control (ADRC) to the DEB structure, where the coal quality variation is deemed as a kind of unknown disturbance that can be estimated and mitigated promptly. Firstly, the nonlinearity of a recent power plant model is analyzed based on the gap metric, which provides guidance on how to set the pressure set-point in line with the power demand. Secondly, the approximate decoupling effect of the DEB structure is analyzed based on the relative gain analysis in frequency domain. Finally, the synthesis of the DEB based ADRC control system is carried out based on multi-objective optimization. The optimized ADRC results show that the integrated absolute error (IAE) indices of the tracking performances in both loops can be simultaneously improved, in comparison with the DEB based PI control and H ∞ control system. The regulation performance in the presence of the coal quality variation is significantly improved under the ADRC control scheme. Moreover, the robustness of the proposed strategy is shown comparable with the H ∞ control. Copyright © 2017. Published by Elsevier Ltd.

  5. Stick balancing, falls and Dragon-Kings

    Science.gov (United States)

    Cabrera, J. L.; Milton, J. G.

    2012-05-01

    The extent to which the occurrence of falls, the dominant feature of human attempts to balance a stick at their fingertip, can be predicted is examined in the context of the "Dragon-King" hypothesis. For skilled stick balancers, fluctuations in the controlled variable, namely the vertical displacement angle θ, exhibit power law behaviors. When stick balancing is made less stable by either decreasing the length of the stick or by requiring the subject to balance the stick on the surface of a table tennis racket, systematic departures from the power law behaviors are observed in the range of large θ. This observation raises the possibility that the presence of departures from the power law in the large length scale region, possibly Dragon-Kings, may identify situations in which the occurrence of a fall is more imminent. However, whether or not Dragon-Kings are observed, there is a Weibull-type survival function for stick falling. The possibility that increased risk of falling can, at least to some extent, be predicted from fluctuations in the controlled variable before the event occurs has important implications for the development of preventative strategies for the management of phenomena ranging from earthquakes to epileptic seizures to falls in the elderly.

  6. Effect of a combination of whole body vibration exercise and squat training on body balance, muscle power, and walking ability in the elderly.

    Science.gov (United States)

    Osugi, Tomohiro; Iwamoto, Jun; Yamazaki, Michio; Takakuwa, Masayuki

    2014-01-01

    A randomized controlled trial was conducted to clarify the beneficial effect of whole body vibration (WBV) exercise plus squat training on body balance, muscle power, and walking ability in the elderly with knee osteoarthritis and/or spondylosis. Of 35 ambulatory patients (14 men and 21 women) who were recruited at our outpatient clinic, 28 (80.0%, 12 men and 16 women) participated in the trial. The subjects (mean age 72.4 years) were randomly divided into two groups (n=14 in each group), ie, a WBV exercise alone group and a WBV exercise plus squat training group. A 4-minute WBV exercise (frequency 20 Hz) was performed 2 days per week in both groups; squat training (20 times per minute) was added during the 4-minute WBV training session in the WBV exercise plus squat training group. The duration of the trial was 6 months. The exercise and training program was safe and well tolerated. WBV exercise alone improved indices of body balance and walking velocity from baseline values. However, WBV exercise plus squat training was more effective for improving tandem gait step number and chair-rising time compared with WBV exercise alone. These results suggest the benefit and safety of WBV exercise plus squat training for improving physical function in terms of body balance and muscle power in the elderly.

  7. One session of high-intensity interval training (HIIT) every 5 days, improves muscle power but not static balance in lifelong sedentary ageing men: A randomized controlled trial.

    Science.gov (United States)

    Sculthorpe, Nicholas F; Herbert, Peter; Grace, Fergal

    2017-02-01

    Declining muscle power during advancing age predicts falls and loss of independence. High-intensity interval training (HIIT) may improve muscle power, but remains largely unstudied in ageing participants. This randomized controlled trial (RCT) investigated the efficacy of a low-frequency HIIT (LfHIIT) intervention on peak muscle power (peak power output [PPO]), body composition, and balance in lifelong sedentary but otherwise healthy males. Thirty-three lifelong sedentary ageing men were randomly assigned to either intervention (INT; n = 22, age 62.3 ± 4.1 years) or control (n = 11, age 61.6 ± 5.0 years) who were both assessed at 3 distinct measurement points (phase A), after 6 weeks of conditioning exercise (phase B), and after 6 weeks of HIIT once every 5 days in INT (phase C), where control remained inactive throughout the study. Static balance remained unaffected, and both absolute and relative PPO were not different between groups at phases A or B, but increased significantly in INT after LfHIIT (P < 0.01). Lean body mass displayed a significant interaction (P < 0.01) due to an increase in INT between phases B and C (P < 0.05). 6 weeks of LfHIIT exercise feasible and effective method to induce clinically relevant improvements in absolute and relative PPO, but does not improve static balance in sedentary ageing men.

  8. [Influence of ski boots on balance performance].

    Science.gov (United States)

    Mildner, E; Lembert, S; Raschner, C

    2010-03-01

    Modern ski carving technique demands that skiers have a strong sense of balance and edge their skis with precision and feeling. Stiff ski boots facilitate the transfer of power to the ski but increase the difficulty of balancing. The aim of this study was to analyse the influence of ski boots on balance performance of alpine skiers. 76 experienced skiers (female 33/male 43) and 76 ski racers of the Skigymnasium Stams (female 31/male 45) were tested on the MFT S 3 Check with and without ski boots. Ski boots significantly influenced balance. There were also significant differences between experienced skiers and ski racers, but gender differences were minimal. In addition to general conditioning, skiers should utilise general and ski-specific balance and sensomotor training which could help in ski injury prevention, especially knee injuries. Georg Thieme Verlag KG Stuttgart, New York.

  9. Macroscopic electromagnetic properties of the Irvine Field-Reversed Configuration: Equilibrium, power balance and fluctuations

    Science.gov (United States)

    Trask, Erik Harold

    The plasma parameters and characteristics of the Irvine Field-Reversed Configuration (IFRC) are summarized in this thesis. Particular emphasis is placed on the development of the different diagnostics used to make measurements in the experiment, as well as the measurements themselves. Whenever possible, actual measurements are used in lieu of theoretical or analytical fits to data. Analysis of magnetic probes (B-dots) comprises the bulk of what is known about the IFRC. From these B-dot probes, the magnetic field structure in a two dimensional plane at constant toroidal position has been determined, and has been found to be consistent with a field-reversed configuration. Peak reversed fields of approximately 250 Gauss have been observed. Further analyses have been developed to extract information from the magnetic field structure, including components of the electric field, the current density, and plasma pressure in the same two dimensional plane. Electric field magnitudes reach 600 V/m, concurrent with current densities greater than 105 Amps/m2 and thermal pressures over 200 Pa. Spectroscopic analysis of hydrogen lines has been done to make estimates of the electron temperature, while spectroscopic measurements of the Doppler broadening of the Halpha line31 have allowed an estimate of the ion temperature. Particle losses out one axial end plane measured by an array of Faraday cups quantify the how well the configuration traps particles. Spectral information derived from B-dot probes indicates that there is substantial power present at frequencies lying between the hydrogen cyclotron and mean gyrofrequency. These various measurements are used to find the following parameters that characterize the Irvine FRC: (1) Electromagnetic and thermal stored energies as functions of time. (2) Power balance, including input power from the field coils, resistive heating, power lost by particle transport and radiation, and particle and energy confinement times. (3) Strong

  10. Preventing Control Constraint Violations by Use of Energy Balances for a Class of Coupled Systems: Applied to a Power Plant

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2007-01-01

    recomputes the reference values to the system such that control signal constraint violations are avoided. The new reference values are found using an energy balance of the system. The scheme is intended to handle rarely occurring constraint violations, so the only concern is that the system should be stable...... and not to optimize performance during all conditions. The scheme is applied to an example with a coal mill pulverizing coal for a power plant.  ...

  11. How Should Equation Balancing Be Taught?

    Science.gov (United States)

    Porter, Spencer K.

    1985-01-01

    Matrix methods and oxidation-number methods are currently advocated and used for balancing equations. This article shows how balancing equations can be introduced by a third method which is related to a fundamental principle, is easy to learn, and is powerful in its application. (JN)

  12. Balancing services in smart electricity grids enabled by market-driven software agents

    NARCIS (Netherlands)

    Warmer, C.J.; Kamphuis, I.G.; Hermans, R.M.; Frunt, J.; Jokic, A.; Bosch, van den P.P.J.

    2010-01-01

    An important prerequisite for reliable and stable operation of electrical power grids is that supply and demand of power are balanced at all times. In traditional, centrally-controlled electrical power networks, real-time balancing is usually implemented by adjusting large-scale generation to

  13. Report on the balancing mechanism: November 2015

    International Nuclear Information System (INIS)

    2015-11-01

    Electricity is stored in very limited volumes. At any time, generation therefore has to be equal to consumption. RTE ensures this balance in real time and factors in generation and consumption contingencies (risks of severe weather, power generation capability, etc). In order to maintain supply-demand balance, RTE has to have a power balancing reserve available in real time for upward and downward adjustment. There are three types of reserves which can be successively deployed. Once the primary and secondary reserves (services controlled by RTE so that power plant generation can be automatically increased or decreased) have been deployed, RTE notifies the generation companies and consumers connected to the grid that the planned operating program needs to be changed very rapidly. This is the role of the balancing mechanism (or tertiary reserve) set up in 2003. The market participants liaising with the power generation companies and the consumers who can do so then make upward and downward bids and notify RTE of their technical and financial conditions. RTE then selects these bids according to their cost and requirements. This mechanism therefore enables the most effective bid in technical and economic terms to be selected. It also makes it possible to resolve congestion on the grid. This phenomenon occurs, for example, if an electrical line is damaged and electricity flows are distributed over neighbouring lines. The monthly reports on this balancing mechanism designed and set up by RTE contain the following information: - summary of the indicators published by the balancing mechanism operation committee, - characteristics of the balancing entities the most deployed during the month, - results of the adjustment-difference accounts up to month M-3, - costs for resolving congestion on the grid up to month M-1, - volumes activated under the terms of the reserve trading contracts concluded between RTE and other TSOs, - reliability rate of the provisional indicators

  14. Report on the balancing mechanism: June 2014

    International Nuclear Information System (INIS)

    2014-06-01

    Electricity is stored in very limited volumes. At any time, generation therefore has to be equal to consumption. RTE ensures this balance in real time and factors in generation and consumption contingencies (risks of severe weather, power generation capability, etc). In order to maintain supply-demand balance, RTE has to have a power balancing reserve available in real time for upward and downward adjustment. There are three types of reserves which can be successively deployed. Once the primary and secondary reserves (services controlled by RTE so that power plant generation can be automatically increased or decreased) have been deployed, RTE notifies the generation companies and consumers connected to the grid that the planned operating program needs to be changed very rapidly. This is the role of the balancing mechanism (or tertiary reserve) set up in 2003. The market participants liaising with the power generation companies and the consumers who can do so then make upward and downward bids and notify RTE of their technical and financial conditions. RTE then selects these bids according to their cost and requirements. This mechanism therefore enables the most effective bid in technical and economic terms to be selected. It also makes it possible to resolve congestion on the grid. This phenomenon occurs, for example, if an electrical line is damaged and electricity flows are distributed over neighbouring lines. The monthly reports on this balancing mechanism designed and set up by RTE contain the following information: - summary of the indicators published by the balancing mechanism operation committee, - characteristics of the balancing entities the most deployed during the month, - results of the adjustment-difference accounts up to month M-3, - costs for resolving congestion on the grid up to month M-1, - volumes activated under the terms of the reserve trading contracts concluded between RTE and other TSOs, - reliability rate of the provisional indicators

  15. Report on the balancing mechanism: January 2016

    International Nuclear Information System (INIS)

    2016-01-01

    Electricity is stored in very limited volumes. At any time, generation therefore has to be equal to consumption. RTE ensures this balance in real time and factors in generation and consumption contingencies (risks of severe weather, power generation capability, etc). In order to maintain supply-demand balance, RTE has to have a power balancing reserve available in real time for upward and downward adjustment. There are three types of reserves which can be successively deployed. Once the primary and secondary reserves (services controlled by RTE so that power plant generation can be automatically increased or decreased) have been deployed, RTE notifies the generation companies and consumers connected to the grid that the planned operating program needs to be changed very rapidly. This is the role of the balancing mechanism (or tertiary reserve) set up in 2003. The market participants liaising with the power generation companies and the consumers who can do so then make upward and downward bids and notify RTE of their technical and financial conditions. RTE then selects these bids according to their cost and requirements. This mechanism therefore enables the most effective bid in technical and economic terms to be selected. It also makes it possible to resolve congestion on the grid. This phenomenon occurs, for example, if an electrical line is damaged and electricity flows are distributed over neighbouring lines. The monthly reports on this balancing mechanism designed and set up by RTE contain the following information: - summary of the indicators published by the balancing mechanism operation committee, - characteristics of the balancing entities the most deployed during the month, - results of the adjustment-difference accounts up to month M-3, - costs for resolving congestion on the grid up to month M-1, - volumes activated under the terms of the reserve trading contracts concluded between RTE and other TSOs, - reliability rate of the provisional indicators

  16. Report on the balancing mechanism: November 2014

    International Nuclear Information System (INIS)

    2014-11-01

    Electricity is stored in very limited volumes. At any time, generation therefore has to be equal to consumption. RTE ensures this balance in real time and factors in generation and consumption contingencies (risks of severe weather, power generation capability, etc). In order to maintain supply-demand balance, RTE has to have a power balancing reserve available in real time for upward and downward adjustment. There are three types of reserves which can be successively deployed. Once the primary and secondary reserves (services controlled by RTE so that power plant generation can be automatically increased or decreased) have been deployed, RTE notifies the generation companies and consumers connected to the grid that the planned operating program needs to be changed very rapidly. This is the role of the balancing mechanism (or tertiary reserve) set up in 2003. The market participants liaising with the power generation companies and the consumers who can do so then make upward and downward bids and notify RTE of their technical and financial conditions. RTE then selects these bids according to their cost and requirements. This mechanism therefore enables the most effective bid in technical and economic terms to be selected. It also makes it possible to resolve congestion on the grid. This phenomenon occurs, for example, if an electrical line is damaged and electricity flows are distributed over neighbouring lines. The monthly reports on this balancing mechanism designed and set up by RTE contain the following information: - summary of the indicators published by the balancing mechanism operation committee, - characteristics of the balancing entities the most deployed during the month, - results of the adjustment-difference accounts up to month M-3, - costs for resolving congestion on the grid up to month M-1, - volumes activated under the terms of the reserve trading contracts concluded between RTE and other TSOs, - reliability rate of the provisional indicators

  17. Report on the balancing mechanism: October 2014

    International Nuclear Information System (INIS)

    2014-10-01

    Electricity is stored in very limited volumes. At any time, generation therefore has to be equal to consumption. RTE ensures this balance in real time and factors in generation and consumption contingencies (risks of severe weather, power generation capability, etc). In order to maintain supply-demand balance, RTE has to have a power balancing reserve available in real time for upward and downward adjustment. There are three types of reserves which can be successively deployed. Once the primary and secondary reserves (services controlled by RTE so that power plant generation can be automatically increased or decreased) have been deployed, RTE notifies the generation companies and consumers connected to the grid that the planned operating program needs to be changed very rapidly. This is the role of the balancing mechanism (or tertiary reserve) set up in 2003. The market participants liaising with the power generation companies and the consumers who can do so then make upward and downward bids and notify RTE of their technical and financial conditions. RTE then selects these bids according to their cost and requirements. This mechanism therefore enables the most effective bid in technical and economic terms to be selected. It also makes it possible to resolve congestion on the grid. This phenomenon occurs, for example, if an electrical line is damaged and electricity flows are distributed over neighbouring lines. The monthly reports on this balancing mechanism designed and set up by RTE contain the following information: - summary of the indicators published by the balancing mechanism operation committee, - characteristics of the balancing entities the most deployed during the month, - results of the adjustment-difference accounts up to month M-3, - costs for resolving congestion on the grid up to month M-1, - volumes activated under the terms of the reserve trading contracts concluded between RTE and other TSOs, - reliability rate of the provisional indicators

  18. Report on the balancing mechanism: March 2014

    International Nuclear Information System (INIS)

    2014-03-01

    Electricity is stored in very limited volumes. At any time, generation therefore has to be equal to consumption. RTE ensures this balance in real time and factors in generation and consumption contingencies (risks of severe weather, power generation capability, etc). In order to maintain supply-demand balance, RTE has to have a power balancing reserve available in real time for upward and downward adjustment. There are three types of reserves which can be successively deployed. Once the primary and secondary reserves (services controlled by RTE so that power plant generation can be automatically increased or decreased) have been deployed, RTE notifies the generation companies and consumers connected to the grid that the planned operating program needs to be changed very rapidly. This is the role of the balancing mechanism (or tertiary reserve) set up in 2003. The market participants liaising with the power generation companies and the consumers who can do so then make upward and downward bids and notify RTE of their technical and financial conditions. RTE then selects these bids according to their cost and requirements. This mechanism therefore enables the most effective bid in technical and economic terms to be selected. It also makes it possible to resolve congestion on the grid. This phenomenon occurs, for example, if an electrical line is damaged and electricity flows are distributed over neighbouring lines. The monthly reports on this balancing mechanism designed and set up by RTE contain the following information: - summary of the indicators published by the balancing mechanism operation committee, - characteristics of the balancing entities the most deployed during the month, - results of the adjustment-difference accounts up to month M-3, - costs for resolving congestion on the grid up to month M-1, - volumes activated under the terms of the reserve trading contracts concluded between RTE and other TSOs, - reliability rate of the provisional indicators

  19. Report on the balancing mechanism: December 2014

    International Nuclear Information System (INIS)

    2014-12-01

    Electricity is stored in very limited volumes. At any time, generation therefore has to be equal to consumption. RTE ensures this balance in real time and factors in generation and consumption contingencies (risks of severe weather, power generation capability, etc). In order to maintain supply-demand balance, RTE has to have a power balancing reserve available in real time for upward and downward adjustment. There are three types of reserves which can be successively deployed. Once the primary and secondary reserves (services controlled by RTE so that power plant generation can be automatically increased or decreased) have been deployed, RTE notifies the generation companies and consumers connected to the grid that the planned operating program needs to be changed very rapidly. This is the role of the balancing mechanism (or tertiary reserve) set up in 2003. The market participants liaising with the power generation companies and the consumers who can do so then make upward and downward bids and notify RTE of their technical and financial conditions. RTE then selects these bids according to their cost and requirements. This mechanism therefore enables the most effective bid in technical and economic terms to be selected. It also makes it possible to resolve congestion on the grid. This phenomenon occurs, for example, if an electrical line is damaged and electricity flows are distributed over neighbouring lines. The monthly reports on this balancing mechanism designed and set up by RTE contain the following information: - summary of the indicators published by the balancing mechanism operation committee, - characteristics of the balancing entities the most deployed during the month, - results of the adjustment-difference accounts up to month M-3, - costs for resolving congestion on the grid up to month M-1, - volumes activated under the terms of the reserve trading contracts concluded between RTE and other TSOs, - reliability rate of the provisional indicators

  20. Power generation from bio methane. Requirements of the EEG 2012 and balancing in gas infrastructure; Verstromung von Biomethan. Anforderungen des EEG 2012 und gaswirtschaftliche Bilanzierung

    Energy Technology Data Exchange (ETDEWEB)

    Herz, Steffen; Bredow, Hartwig von [von Bredow Valentin Rechtsanwaelte, Berlin (Germany)

    2012-12-15

    Six years ago, the first biogas infeed plant was connected to the natural gas distribution system. The infeed of biogas progressed beyond the nursery stage. The infeed of bio methane significantly is promoted by the renewable energy law. One fundamental requirement for the promotion with respect to the Renewable Energy Law is the generation of the power to be remunerated by means of the exclusive use of biomass. The Renewable Energy Law EEG 2012 contains the new requirement, that furthermore the transport of biogas from its production until removal has to be documented by means of a mass balance. Under this aspect, the authors of the contribution under consideration report on the requirements of the EEG 2012 and the balancing in gas infrastructure with respect to the power generation from biomass.

  1. Prediction of Critical Power and W' in Hypoxia: Application to Work-Balance Modelling.

    Science.gov (United States)

    Townsend, Nathan E; Nichols, David S; Skiba, Philip F; Racinais, Sebastien; Périard, Julien D

    2017-01-01

    Purpose: Develop a prediction equation for critical power (CP) and work above CP (W') in hypoxia for use in the work-balance ([Formula: see text]) model. Methods: Nine trained male cyclists completed cycling time trials (TT; 12, 7, and 3 min) to determine CP and W' at five altitudes (250, 1,250, 2,250, 3,250, and 4,250 m). Least squares regression was used to predict CP and W' at altitude. A high-intensity intermittent test (HIIT) was performed at 250 and 2,250 m. Actual and predicted CP and W' were used to compute W' during HIIT using differential ([Formula: see text]) and integral ([Formula: see text]) forms of the [Formula: see text] model. Results: CP decreased at altitude ( P equations for CP and W' developed in this study are suitable for use with the [Formula: see text] model in acute hypoxia. This enables the application of [Formula: see text] modelling to training prescription and competition analysis at altitude.

  2. Balance of leadership in the power economy

    Energy Technology Data Exchange (ETDEWEB)

    Goeschel, G; Wolff, G

    1986-06-05

    The authors depict the management situation in the German power economy. Using the results of a survey which they carried out and practical observations made when conducting seminars for managers in the power economy, they pinpoint weak points in a number of different sectors. They show how suitable management training programmes can rectify this deficit in management skills and consequently improve a company's overall performance.

  3. Energy balance in the ohmically heated FT

    International Nuclear Information System (INIS)

    Bartiromo, R.; Brusati, M.; Cilloco, F.

    1981-01-01

    A typical discharge in the FT Tokamak at 60 kG has been studied in detail in order to derive the power balance between the ohmic input and the plasma losses. Impurity and radiation losses together with ion and electron energy balance are discussed. A power transport term for electrons is derived which is ascribed to anomalous thermal conduction. This resulting thermal transport is compared with those derived from different proposed scalings

  4. Application Of A Balanced Adder-Subtractor In The Solution Of ...

    African Journals Online (AJOL)

    A balanced adder-subtractor employing operational amplifier is used to solve simultaneous linear equations. A pair of simultaneous linear equation with two unknowns have been considered for the design of the balanced adder-subtractor operated from a 6- volts d.c power source. A general purpose operational amplifier, ...

  5. Operation Modeling of Power Systems Integrated with Large-Scale New Energy Power Sources

    Directory of Open Access Journals (Sweden)

    Hui Li

    2016-10-01

    Full Text Available In the most current methods of probabilistic power system production simulation, the output characteristics of new energy power generation (NEPG has not been comprehensively considered. In this paper, the power output characteristics of wind power generation and photovoltaic power generation are firstly analyzed based on statistical methods according to their historical operating data. Then the characteristic indexes and the filtering principle of the NEPG historical output scenarios are introduced with the confidence level, and the calculation model of NEPG’s credible capacity is proposed. Based on this, taking the minimum production costs or the best energy-saving and emission-reduction effect as the optimization objective, the power system operation model with large-scale integration of new energy power generation (NEPG is established considering the power balance, the electricity balance and the peak balance. Besides, the constraints of the operating characteristics of different power generation types, the maintenance schedule, the load reservation, the emergency reservation, the water abandonment and the transmitting capacity between different areas are also considered. With the proposed power system operation model, the operation simulations are carried out based on the actual Northwest power grid of China, which resolves the new energy power accommodations considering different system operating conditions. The simulation results well verify the validity of the proposed power system operation model in the accommodation analysis for the power system which is penetrated with large scale NEPG.

  6. Balance between automation and human actions in nuclear power plant operation. Results of international cooperation

    International Nuclear Information System (INIS)

    Sun, B.; Olmstead, R.; Oudiz, A.; Jenkinson, J.; Kossilov, A.

    1990-01-01

    Automation has long been an established feature of power plants. In some applications, the use of automation has been the significant factor which has enabled plant technology to progress to its current state. Societal demands for increased levels of safety have led to greater use of redundancy and diversity and this, in turn, has increased levels of automation. However, possibly the greatest contributory factor in increased automation has resulted from improvements in information technology. Much recent attention has been focused on the concept of inherently safe reactors, which may simplify safety system requirements and information and control system complexity. The allocation of tasks between man and machine may be one of the most critical activity in the design of new nuclear plants and major retro-fits and it therefore warrants a design approach which is commensurate in quality with the high levels of safety and production performance sought from nuclear plants. Facing this climate, in 1989 the International Atomic Energy Agency (IAEA) formed an advisory group from member countries with extensive experience in nuclear power plant automation. The task of this group was to advise on the appropriate balance between manual and automatic actions in plant operation

  7. Balance between automation and human actions in nuclear power plant operation. Results of international cooperation

    International Nuclear Information System (INIS)

    Sun, B.; Olmstead, R.; Oudiz, A.; Jenkinson, J.; Kossilov, A.

    1990-01-01

    Automation has long been an established feature of power plants. In some applications, the use of automation has been the significant factor which has enabled plant technology to progress to its current state. Societal demands for increased levels of safety have led to greater use of redundancy and diversity and this, in turn, has increased levels of automation. However, possibly the greatest contributory factor in increased automation has resulted from improvements in information technology. Much recent attention has been focused on the concept of inherently safe reactors, which may simplify safety system requirements and information and control system complexity. The allocation of tasks between man and machine may be one of the most critical activity in the design of new nuclear plants and major retro-fits and it therefore warrants a design approach which is commensurate in quality with the high levels of safety and production performance sought from nuclear plants. Facing this climate, in 1989 the International Atomic Energy Agency (IAEA) formed an advisory group from member countries with extensive experience in nuclear power plant automation. The task of this group was to advise on the appropriate balance between manual and automatic actions in plant operation. (author) [fr

  8. Wind power plant system services

    DEFF Research Database (Denmark)

    Basit, Abdul; Altin, Müfit

    Traditionally, conventional power plants have the task to support the power system, by supplying power balancing services. These services are required by the power system operators in order to secure a safe and reliable operation of the power system. However, as in the future the wind power...... is going more and more to replace conventional power plants, the sources of conventional reserve available to the system will be reduced and fewer conventional plants will be available on-line to share the regulation burden. The reliable operation of highly wind power integrated power system might...... then beat risk unless the wind power plants (WPPs) are able to support and participate in power balancing services. The objective of this PhD project is to develop and analyse control strategies which can increase the WPPs capability to provide system services, such as active power balancing control...

  9. Balance equations for a relativistic plasma. Pt. 1

    International Nuclear Information System (INIS)

    Hebenstreit, H.

    1983-01-01

    Relativistic power moments of the four-momentum are decomposed according to a macroscopic four-velocity. The thus obtained quantities are identified as relativistic generalization of the nonrelativistic orthogonal moments, e.g. diffusion flow, heat flow, pressure, etc. From the relativistic Boltzmann equation we then derive balance equations for these quantities. Explicit expressions for the relativistic mass conservation, energy balance, pressure balance, heat flow balance are presented. The weak relativistic limit is discussed. The derivation of higher order balance equations is sketched. (orig.)

  10. Analysis of heat balance on innovative-simplified nuclear power plant using multi-stage steam injectors

    International Nuclear Information System (INIS)

    Goto, Shoji; Ohmori, Shuichi; Mori, Michitsugu

    2006-01-01

    The total space and weight of the feedwater heaters in a nuclear power plant (NPP) can be reduced by replacing low-pressure feedwater heaters with high-efficiency steam injectors (SIs). The SI works as a direct heat exchanger between feedwater from condensers and steam extracted from turbines. It can attain pressures higher than the supplied steam pressure. The maintenance cost is lower than that of the current feedwater heater because of its simplified system without movable parts. In this paper, we explain the observed mechanisms of the SI experimentally and the analysis of the computational fluid dynamics (CFD). We then describe mainly the analysis of the heat balance and plant efficiency of the innovative-simplified NPP, which adapted to the boiling water reactor (BWR) with the high-efficiency SI. The plant efficiencies of this innovative-simplified BWR with SI are compared with those of a 1 100 MWe-class BWR. The SI model is adopted in the heat balance simulator as a simplified model. The results show that the plant efficiencies of the innovate-simplified BWR with SI are almost equal to those of the original BWR. They show that the plant efficiency would be slightly higher if the low-pressure steam, which is extracted from the low-pressure turbine, is used because the first-stage of the SI uses very low pressure. (author)

  11. Spreading law of non-Newtonian power-law liquids on a spherical substrate by an energy-balance approach.

    Science.gov (United States)

    Iwamatsu, Masao

    2017-07-01

    The spreading of a cap-shaped spherical droplet of non-Newtonian power-law liquids, both shear-thickening and shear-thinning liquids, that completely wet a spherical substrate is theoretically investigated in the capillary-controlled spreading regime. The crater-shaped droplet model with the wedge-shaped meniscus near the three-phase contact line is used to calculate the viscous dissipation near the contact line. Then the energy balance approach is adopted to derive the equation that governs the evolution of the contact line. The time evolution of the dynamic contact angle θ of a droplet obeys a power law θ∼t^{-α} with the spreading exponent α, which is different from Tanner's law for Newtonian liquids and those for non-Newtonian liquids on a flat substrate. Furthermore, the line-tension dominated spreading, which could be realized on a spherical substrate for late-stage of spreading when the contact angle becomes low and the curvature of the contact line becomes large, is also investigated.

  12. In the balance

    DEFF Research Database (Denmark)

    Kluth, Michael Friederich; Pilegaard, Jess

    The present paper seeks to make sense of recent EU naval capability changes by applying neo-realist theory on the EU as an international actor in the global balance of power. The paper compares three different strands of Neo-realist theory by deducting key predictions about the expected defense...... posture of the Union and the expected changes in naval capabilities. The predictions are subsequently held up against recent data on naval military build-up in the EU. The paper argues that the observed patterns are best explained not as bandwagoning with the United States, but as a long-term balancing...

  13. Brazilian energy balance 2002: calendar year 2001

    International Nuclear Information System (INIS)

    2002-12-01

    The Brazilian Energy Balance 2002, based on 2001 data, contains the information related to the supply and consumption of the primary and secondary energy sources, provided by data and information of responsible sectors. This version presents important differences in relation to the previous editions, new technical concepts were introduced for the treatment of calorific powers of energy sources in the composition and consolidation of data, and also in the structure of its contents. The Balance 2002 was structured in the same way of the last edition, divided in 8 chapters, as follows: summary of the relevant indicators of 2001 and consolidated data of production, consumption and external dependence on energy, and also the sectorial composition of the consumption of the different groups of energy sources - period 1970/2001; energy supply and demand by source - 1986/2001; energy consumption by sector - 1986/2001; energy foreign trading - 1986/2001; transformation centers balances - 1986/2001; energy resources and reserves - 1973/2001; energy and socio-economy - 1986/2001; regional parameters and appendices including: installed capacity, international data, general structure of the balance, information processing, conversion units and consolidated energy balances - 1970/2001,in the 'kcal' unit, calculated in PCI- Inferior Calorific Power. This new model has the intention to approximate the Brazilian Energy Balance to the international methodologies, mainly to the OECD balances

  14. Reaction-rate coefficients, high-energy ions slowing-down, and power balance in a tokamak fusion reactor plasma

    International Nuclear Information System (INIS)

    Tone, Tatsuzo

    1978-07-01

    Described are the reactivity coefficient of D-T fusion reaction, slowing-down processes of deuterons injected with high energy and 3.52 MeV alpha particles generated in D-T reaction, and the power balance in a Tokamak reactor plasma. Most of the results were obtained in the first preliminary design of JAERI Experimental Fusion Reactor (JXFR) driven with stationary neutral beam injection. A manual of numerical computation program ''BALTOK'' developed for the calculations is given in the appendix. (auth.)

  15. Voltage-Balancing Method for Modular Multilevel Converters Switched at Grid Frequency

    DEFF Research Database (Denmark)

    Deng, Fujin; Chen, Zhe

    2015-01-01

    The modular multilevel converter (MMC) becomes attractive for high-voltage and high-power applications due to its high modularity, availability, and power quality. The voltage balance issue of capacitors is very important in the MMC, and the balancing of the capacitor voltage is increasingly...

  16. The system of parliamentary government: The possibility of balance under the principle of the separation of powers

    Directory of Open Access Journals (Sweden)

    Pejić Irena

    2016-01-01

    Full Text Available The minimum consensus in defining the concept of a parliamentary system is closely related to the presence of the responsible government in the system governed by the principle of the separation of powers, which is the essential characteristic of parliamentarism. A constitutional and political theory classify this system as a model of parliamentary government that is elected by Parliament and responsible to Parliament, which is the essence and the common denominator of this system. Moreover, all the modalities of the system develop in line with the relations established between the legislative and the executive authorities, i.e. between the head of state, the government and the parliament. Nowadays, there is no 'pure' model of the parliamentary government, for at least two reasons. First, modern constitutions set up instruments of rationalization and transfer the focus of the constitutional power either to the government or to the head of state, but in any case 'away from' the parliament. Second, political framework of modern parliamentarism significantly contributes to the situation where the constitutional instruments aimed at preserving the balance receive a new legal and political meaning; thus, they serve some functions other than those prescribed by the constitution.

  17. Distributed control of deregulated electrical power networks

    NARCIS (Netherlands)

    Hermans, R.M.

    2012-01-01

    A prerequisite for reliable operation of electrical power networks is that supply and demand are balanced at all time, as efficient ways for storing large amounts of electrical energy are scarce. Balancing is challenging, however, due to the power system's dimensions and complexity, the low

  18. Power balance in ELMO Bumpy Torus: bulk electrons and ions in a 37 kW discharge

    International Nuclear Information System (INIS)

    McNeill, D.H.

    1985-10-01

    The power balance of the bulk electrons and ions in discharges with 37 kW of applied microwave power in the ELMO Bumpy Torus (EBT) is examined in a zero-dimensional model using data on the intensity and linewidth of the molecular and atomic hydrogen emission. At least 60% of the applied power is ultimately dissipated by processes involving the neutral particles, including dissociation of molecules, ionization of and radiation from atoms, and heating of cold electrons produced during atomic ionization. The molecular influx rate and the density of atoms are used independently to determine the bulk electron particle confinement time, and an upper bound estimate is made of the diffusional power loss from the bulk plasma electrons. Parameters derived from the basic spectroscopic data presented in this paper include the neutral atom density 2 - 5x10 10 cm -3 , incident molecular flux 3 - 5x10 15 cm -2 s -1 , bulk ion temperature approx. =3 eV, and particle confinement time <1.1 ms. The bulk electron energy confinement time is 0.7 ms or less in the standard operating regime. Published data on the nonthermal electron and ion populations in the plasma are used to evaluate approximately the overall energy flow in the discharge. 54 refs

  19. The United States, the Soviet Union/Russia and the strategic and military balance of power between 1989 and 2016

    Directory of Open Access Journals (Sweden)

    João Fábio Bertonha

    2016-03-01

    Full Text Available The international system has changed dramatically after the fall of the Berlin Wall and the collapse of the USSR. These changes include economic, social and political aspects, as well as the strategic and military ones. This article discusses the changes in the world balance of power, regarding military and strategic aspects, in the period of almost thirty years after the fall of the Berlin Wall. The cases of the United States and the Soviet Union/Russian Federation will be specially addressed.

  20. A standard description and costing methodology for the balance-of-plant items of a solar thermal electric power plant. Report of a multi-institutional working group

    Science.gov (United States)

    1983-01-01

    Standard descriptions for solar thermal power plants are established and uniform costing methodologies for nondevelopmental balance of plant (BOP) items are developed. The descriptions and methodologies developed are applicable to the major systems. These systems include the central receiver, parabolic dish, parabolic trough, hemispherical bowl, and solar pond. The standard plant is defined in terms of four categories comprising (1) solar energy collection, (2) power conversion, (3) energy storage, and (4) balance of plant. Each of these categories is described in terms of the type and function of components and/or subsystems within the category. A detailed description is given for the BOP category. BOP contains a number of nondevelopmental items that are common to all solar thermal systems. A standard methodology for determining the costs of these nondevelopmental BOP items is given. The methodology is presented in the form of cost equations involving cost factors such as unit costs. A set of baseline values for the normalized cost factors is also given.

  1. CMOS current controlled fully balanced current conveyor

    International Nuclear Information System (INIS)

    Wang Chunhua; Zhang Qiujing; Liu Haiguang

    2009-01-01

    This paper presents a current controlled fully balanced second-generation current conveyor circuit (CF-BCCII). The proposed circuit has the traits of fully balanced architecture, and its X-Y terminals are current controllable. Based on the CFBCCII, two biquadratic universal filters are also proposed as its applications. The CFBCCII circuits and the two filters were fabricated with chartered 0.35-μm CMOS technology; with ±1.65 V power supply voltage, the total power consumption of the CFBCCII circuit is 3.6 mW. Comparisons between measured and HSpice simulation results are also given.

  2. Construction of a new watt balance with the goal to realize the kilogram in the US

    Science.gov (United States)

    Schlamminger, Stephan; Haddad, Darine; Seifert, Frank; Chao, Leon; Newell, David; Pratt, Jon

    2015-04-01

    A watt balance is a mechanical device that compares mechanical power to electrical power. Since electrical power is measured using quantum physics by employing the Josephson effect and the Quantum Hall effect, electrical power can be measured as a product of a known factor, two frequencies, and the Planck constant h. Mechanical power is given by mgv , where m is the mass of a weight, g the local acceleration, and v the velocity. Hence, the watt balance provides a link between mass and Planck's constant. Currently several watt balances worldwide are employed to measure h. A redefinition of the international system of units (SI) is currently in discussion and may become reality as early as 2018. In the new SI, the numerical value of the Planck constant will be fixed and the watt balance is a means to realize the unit of mass. Researchers at NIST are preparing for a new SI and we have started in 2011 with plans to design a new watt balance capable of realizing the kilogram with relative uncertainties of a few parts in 108. Construction of the new watt balance has started in 2014. In my talk, I will show some of the latest results achieved with this apparatus.

  3. Report on the balancing mechanism from February 2016

    International Nuclear Information System (INIS)

    2016-02-01

    Electricity is stored in very limited volumes. At any time, generation therefore has to be equal to consumption. RTE ensures this balance in real time and factors in generation and consumption contingencies (risks of severe weather, power generation capability, etc). In order to maintain supply-demand balance, RTE has to have a power balancing reserve available in real time for upward and downward adjustment. There are three types of reserves which can be successively deployed. Once the primary and secondary reserves (services controlled by RTE so that power plant generation can be automatically increased or decreased) have been deployed, RTE notifies the generation companies and consumers connected to the grid that the planned operating program needs to be changed very rapidly. This is the role of the balancing mechanism (or tertiary reserve) set up in 2003. The market participants liaising with the power generation companies and the consumers who can do so then make upward and downward bids and notify RTE of their technical and financial conditions. RTE then selects these bids according to their cost and requirements. This mechanism therefore enables the most effective bid in technical and economic terms to be selected. It also makes it possible to resolve congestion on the grid. This phenomenon occurs, for example, if an electrical line is damaged and electricity flows are distributed over neighbouring lines. The monthly reports on this balancing mechanism designed and set up by RTE contain the following information: - summary of the indicators published by the balancing mechanism operation committee, - characteristics of the balancing entities the most deployed during the month, - results of the adjustment-difference accounts up to month M-3, - costs for resolving congestion on the grid up to month M-1, - volumes activated under the terms of the reserve trading contracts concluded between RTE and other TSOs, - reliability rate of the provisional indicators

  4. Report on the balancing mechanism from May 2016

    International Nuclear Information System (INIS)

    2016-05-01

    Electricity is stored in very limited volumes. At any time, generation therefore has to be equal to consumption. RTE ensures this balance in real time and factors in generation and consumption contingencies (risks of severe weather, power generation capability, etc). In order to maintain supply-demand balance, RTE has to have a power balancing reserve available in real time for upward and downward adjustment. There are three types of reserves which can be successively deployed. Once the primary and secondary reserves (services controlled by RTE so that power plant generation can be automatically increased or decreased) have been deployed, RTE notifies the generation companies and consumers connected to the grid that the planned operating programme needs to be changed very rapidly. This is the role of the balancing mechanism (or tertiary reserve) set up in 2003. The market participants liaising with the power generation companies and the consumers who can do so then make upward and downward bids and notify RTE of their technical and financial conditions. RTE then selects these bids according to their cost and requirements. This mechanism therefore enables the most effective bid in technical and economic terms to be selected. It also makes it possible to resolve congestion on the grid. This phenomenon occurs, for example, if an electrical line is damaged and electricity flows are distributed over neighbouring lines. The monthly reports on this balancing mechanism designed and set up by RTE contain the following information: - summary of the indicators published by the balancing mechanism operation committee, - characteristics of the balancing entities the most deployed during the month, - results of the adjustment-difference accounts up to month M-3, - costs for resolving congestion on the grid up to month M-1, - volumes activated under the terms of the reserve trading contracts concluded between RTE and other TSOs, - reliability rate of the provisional indicators

  5. The effects of forecast errors on the merchandising of wind power

    International Nuclear Information System (INIS)

    Roon, Serafin von

    2012-01-01

    A permanent balance between consumption and generation is essential for a stable supply of electricity. In order to ensure this balance, all relevant load data have to be announced for the following day. Consequently, a day-ahead forecast of the wind power generation is required, which also forms the basis for the sale of the wind power at the wholesale market. The main subject of the study is the short-term power supply, which compensates errors in wind power forecasting for balancing the wind power forecast errors at short notice. These forecast errors effects the revenues and the expenses by selling and buying power in the day-ahead, intraday and balance energy market. These price effects resulting from the forecast errors are derived from an empirical analysis. In a scenario for the year 2020 the potential of conventional power plants to supply power at short notice is evaluated from a technical and economic point of view by a time series analysis and a unit commitment simulation.

  6. CONSEQUENCES OF A SHIFT IN THE POWER BALANCE FOR THE MARKET OF SERVICES

    Directory of Open Access Journals (Sweden)

    Frits van den BERG

    2008-06-01

    Full Text Available This article starts with some observations on changes in the power balance between clients and suppliers in the service industry. The main forces between these changes are more information in the hands of clients (by use of internet and personal experiences and less information received by suppliers (by less contact with potential clients because of cost reduction. These changes can be translated into the replacement of a demand oriented market by a demand driven market. For suppliers of services to individuals in such a market two aspects are highly relevant. First the client will formulate his wishes in a kind of "Terms of Reference" and the supplier has to search for interesting requests. This instead of the client searching on internet or somewhere else for the best standard offer. In the second place the client will formulate his wishes often in a way that a single enterprise cannot deliver what is wanted. In order to survive chains of enterprises have to be formed. I mentioned a few of the vulnerable points of chains, points which need to have attention in the contract between the links of the chain.

  7. Online dynamic equalization adjustment of high-power lithium-ion battery packs based on the state of balance estimation

    International Nuclear Information System (INIS)

    Wang, Shunli; Shang, Liping; Li, Zhanfeng; Deng, Hu; Li, Jianchao

    2016-01-01

    Highlights: • A novel concept (SOB, State of Balance) is proposed for the LIB pack equalization. • Core parameter detection and filtering is analyzed to identify the LIB pack behavior. • The electrical UKF model is adopted for the online dynamic estimation. • The equalization target model is built based on the optimum preference. • Comprehensive imbalance state calculation is implemented for the adjustment. - Abstract: A novel concept named as state of balance (SOB) is proposed and its online dynamic estimation method is presented for the high-power lithium-ion battery (LIB) packs, based on which the online dynamic equalization adjustment is realized aiming to protect the operation safety of its power supply application. The core parameter detection method based on the specific moving average algorithm is studied because of their identical varying characteristics on the individual cells due to the manufacturing variability and other factors, affecting the performance of the high-power LIB pack. The SOB estimation method is realized with the detailed deduction, in which a dual filter consisting of the Unscented Kalman filter (UKF), equivalent circuit model (ECM) and open circuit voltage (OCV) is used in order to predict the SOB state. It is beneficial for the energy operation and the energy performance state can be evaluated online prior to the adjustment method based on the terminal voltage consistency. The energy equalization is realized that is based on the credibility reasoning together with the equalization model building process. The experiments including the core parameter detection, SOB estimation and equalization adjustment are done and the experimental results are analyzed. The experiment results show that the numerical Coulomb efficiency is bigger than 95%. The cell voltage measurement error is less than 5 mV and the terminal voltage measurement error of the LIB pack is less than 1% FS. The measurement error of the battery discharge and charge

  8. Energy analysis of power systems

    International Nuclear Information System (INIS)

    2004-01-01

    Next to economic viability, the holistic energy balance of electricity generation options' is a factor of major importance. All aspects of the energy balance, i. e. all expenditures and all revenues, are compared in a life cycle analysis. This turns out to be a complex task, especially because of the large number of input quantities to be determined, including the balancing limits to be taken into account. The article presents in detail the findings of analyses of energy balances for various types of nuclear power plants as well as electricity generation in fossil-fired power plants, and for renewable energies. The analyses and their databases are discussed. Moreover, the findings are presented for the energetic amortization periods and the amounts of CO 2 emissions specific to the respective generating technologies. (orig.)

  9. THE PRINCIPLE OF SEPARATION OF POWERS - CONSTITUTIONAL GUARANTEE

    Directory of Open Access Journals (Sweden)

    Emilian CIONGARU

    2017-05-01

    Full Text Available The principle of ensuring the legal bases of the State functioning is the fundamental principle of law which actually settles down the principle of separation of powers: legislative, executive and judicial power. Over the time, the principle of separation of powers, although in practice its enforcement experienced more than two centuries, it hasn’t expressed itself in a pure form, not even in the most advanced democracies. Whether it is approached the thesis of a more flexible or more rigid separation of powers or the thesis on certain exceptions to those two situations specific to certain political regimes, the principle of separation of powers is the fundamental mechanism in ensuring a balance of powers and preventing the establishment of a dictatorial or authoritarian regime. The complex content of the rule of law consists of: the rule of law regency; the capitalization on the actual size of the fundamental rights and freedoms; the achievement of the balance/mutual cooperation of public authorities and the performance of free access to justice. If the form of State organization of the political power of the people is done by several groups or categories of State bodies with functions and features clearly defined and characterized by organizational and functional autonomy, as well as mutual balance and collaboration, it is emerging the principle of separation of the State powers balance.

  10. Two-Step Load Balancing Scheme for Fairness Improvement in ...

    African Journals Online (AJOL)

    ABSTRACT: The problem of load imbalance in HetNets among wireless access technologies is addressed in this article. ... balancing could either mean balancing the transmit power or the radio ..... Weight for Multimedia Transmission.

  11. Optimal Operation of Plug-In Electric Vehicles in Power Systems with High Wind Power Penetrations

    DEFF Research Database (Denmark)

    Hu, Weihao; Su, Chi; Chen, Zhe

    2013-01-01

    in the power systems with high wind power penetrations. In this paper, the integration of plug-in electric vehicles in the power systems with high wind power penetrations is proposed and discussed. Optimal operation strategies of PEV in the spot market are proposed in order to decrease the energy cost for PEV......The Danish power system has a large penetration of wind power. The wind fluctuation causes a high variation in the power generation, which must be balanced by other sources. The battery storage based Plug-In Electric Vehicles (PEV) may be a possible solution to balance the wind power variations...... owners. Furthermore, the application of battery storage based aggregated PEV is analyzed as a regulation services provider in the power system with high wind power penetrations. The western Danish power system where the total share of annual wind power production is more than 27% of the electrical energy...

  12. Performance of automatic generation control mechanisms with large-scale wind power

    Energy Technology Data Exchange (ETDEWEB)

    Ummels, B.C.; Gibescu, M.; Paap, G.C. [Delft Univ. of Technology (Netherlands); Kling, W.L. [Transmission Operations Department of TenneT bv (Netherlands)

    2007-11-15

    The unpredictability and variability of wind power increasingly challenges real-time balancing of supply and demand in electric power systems. In liberalised markets, balancing is a responsibility jointly held by the TSO (real-time power balancing) and PRPs (energy programs). In this paper, a procedure is developed for the simulation of power system balancing and the assessment of AGC performance in the presence of large-scale wind power, using the Dutch control zone as a case study. The simulation results show that the performance of existing AGC-mechanisms is adequate for keeping ACE within acceptable bounds. At higher wind power penetrations, however, the capabilities of the generation mix are increasingly challenged and additional reserves are required at the same level. (au)

  13. Balancing fast-rotating parts of hand-held machine drive

    Science.gov (United States)

    Korotkov, V. S.; Sicora, E. A.; Nadeina, L. V.; Yongzheng, Wang

    2018-03-01

    The article considers the issues related to the balancing of fast rotating parts of the hand-held machine drive including a wave transmission with intermediate rolling elements, which is constructed on the basis of the single-phase collector motor with a useful power of 1 kW and a nominal rotation frequency of 15000 rpm. The forms of balancers and their location are chosen. The method of balancing is described. The scheme for determining of residual unbalance in two correction planes is presented. Measurement results are given in tables.

  14. Analysis on the heat balance between CEFR and the primary loop system

    International Nuclear Information System (INIS)

    Liu Shangbo; Yang Hongyi; Li Jing; Wang Xiongying

    2013-01-01

    The heat balance ability of reactor is very important to design and operation. Special heat balance analysis and calculation software shall be available. This article analyzes and calculates in details the heat source and cooling power of the main cooling system of the primary loop in China Experimental Faster Reactor (CEFR), and develops a calculation code. By using the steady state heat balance data of 26.5% Pn and 40% Pn in CEFR during power start-up, the heat balance ability of the primary loop is verified. The results show that the calculation model is reliable, and can provide technical support to building heat balance in CEFR operation. (authors)

  15. Independent from muscle power and balance performance, a creatinine clearance below 65 ml/min is a significant and independent risk factor for falls and fall-related fractures in elderly men and women diagnosed with osteoporosis.

    Science.gov (United States)

    Dukas, L; Schacht, E; Runge, M

    2010-07-01

    We assessed in a cross-sectional study in elderly men and women with osteoporosis, the association between the creatinine clearance (CrCl) and the performance in different balance and muscle power and function tests and found that a decreasing creatinine clearance was significantly associated with lower balance and muscle power. To determine if a creatinine clearance of balance and an increased risk for falls and fractures. We assessed in a cross-sectional-study in 1781 German osteoporotic patients, the association between the CrCl, the physical performance, and the number of falls and fractures. Controlling for age, gender, BMI, and osteoporosis treatment (fracture analysis only), a decreasing CrCl was associated with lower physical performance in the timed-up-and-go test (corr -0.2337, P risk for falls (47.7% vs. 36.2%, P = 0.0008) and fall-related fractures (33.1% vs. 22.9%, P = 0.0003) compared with a CrCl of >or=65 ml/min. In this study, we found a significant gender-independent correlation between decreasing CrCl and lower performance in balance and muscle power tests. Reduced muscle power and balance may therefore be involved in the low creatinine clearance associated increased risk for falls and fall-related fractures. Furthermore, we found that a CrCl balance tests, is a significant risk factor for falls and fractures.

  16. THE PROBLEM OF MONITORING AND BALANCING OF VEHICLE BATTERIES

    Directory of Open Access Journals (Sweden)

    Aleksandr Inshakov

    2016-03-01

    Full Text Available The use of electrochemical energy storage units is becoming more common, and they are subject to new requirements for increasing the time of electrical supply for power equipment. In some cases, batteries serve as the main electric power unit working under reserved electric load and on the electric drive of the vehicle. The article discusses the features of using batteries as a part of electrical equipment for the agricultural vehicles. When creating high-capicity batteries trhrough connecting some batteries in series and parallel circuits, there are a number of features caused by variations of the parameters of the elements. Materials and Methods The object of research is methods of monitoring and balancing touch batteries are connected in series and there is no possibility or desirability of their disconnection for individual balancing. In the development of methods and devices used in general engineering approaches to the development of technical devices. Results It is necessary to find the causes affecting the energy characteristics and service life of the battery to increase it. During research we have found a need for monitoring and control of battery status, which allow solving the problems of divergence of containers, the internal resistance and leakage of individual batteries. Temperature of the battery is an important indicator to control it. Balancing the battery system and monitoring systems are needed to provide a uniform charge of individual cells, regardless of the variation parameters. Discussion and Conclusions There are different variants of balancing systems, each of which has its own advantages and disadvantages. The article gives examples of the construction of five alignment sys¬tems stress on the individual cells of the battery. The criteria for selection for the current passive balancing method using shunt resistors, and are a diagram of an improved pas¬sive way of balancing. Considered and the basic advantages and

  17. Economic evaluation of offshore wind power in the liberalized Dutch power market

    NARCIS (Netherlands)

    Chang, J.; Ummels, B.C.; Sark, van W.G.J.H.M.; Rooijen, den H.P.G.M.; Kling, W.L.

    2009-01-01

    The variability and limited predictability of wind power challenges the operation of power systems, where the generation and load are required in balance at all times. The transmission system operator (TSO) is the responsible party. In a liberalized energy sector, key technical elements of power

  18. Balancing mechanism status: November 2009

    International Nuclear Information System (INIS)

    2009-01-01

    RTE ensures the real-time balance between production and consumption and deals with congestion on the French electricity system. The Balancing Mechanism assists in the accomplishment of this task. As in many countries, and after extensive dialogue with representatives from the market's various players, RTE proposes a Balancing Mechanism in the form of a permanent and transparent system of calls for tender. The system is open to everyone and provides a real-time reserve of power that can be used for balancing either upward or downward. RTE takes advantage of these offers according to economic precedence, taking into account the system's operating conditions. It pays for them at the offer price. There are two types of offer: - Upward offer: increase in production, decrease in consumption, imports, - Downward offer: decrease in production, increase in consumption, exports. For a Balancing Entity, an offer systematically consists of: a balancing direction (upward/downward), a time period, a price that may vary according to six time slots. RTE publishes each month a Balancing Mechanism Report. which includes the following information: - energy volumes activated to ensure the balance of the system and to resolve congestion; - minimum and maximum prices of offers activated to balance the system; - daily trends calculated according to the predominant value of the overall upward or downward trend; - balancing shares by technology (nuclear, thermal, hydraulic); - characteristics of the five most activated balancing entities; - balances/imbalances accounts and production/consumption overcharge; - congestion curbing costs on the French electricity system; - energy volumes activated to ensure the balance of the system according to contracts between RTE and other Balance Responsible entities (UK, Belgium, Italy, Germany, Switzerland); - reliability of the provisional data supplied by RTE about the balancing trend; - availability of RTE's information services (planning, balancing

  19. Balancing mechanism status: May 2009

    International Nuclear Information System (INIS)

    2009-01-01

    RTE ensures the real-time balance between production and consumption and deals with congestion on the French electricity system. The Balancing Mechanism assists in the accomplishment of this task. As in many countries, and after extensive dialogue with representatives from the market's various players, RTE proposes a Balancing Mechanism in the form of a permanent and transparent system of calls for tender. The system is open to everyone and provides a real-time reserve of power that can be used for balancing either upward or downward. RTE takes advantage of these offers according to economic precedence, taking into account the system's operating conditions. It pays for them at the offer price. There are two types of offer: - Upward offer: increase in production, decrease in consumption, imports, - Downward offer: decrease in production, increase in consumption, exports. For a Balancing Entity, an offer systematically consists of: a balancing direction (upward/downward), a time period, a price that may vary according to six time slots. RTE publishes each month a Balancing Mechanism Report. which includes the following information: - energy volumes activated to ensure the balance of the system and to resolve congestion; - minimum and maximum prices of offers activated to balance the system; - daily trends calculated according to the predominant value of the overall upward or downward trend; - balancing shares by technology (nuclear, thermal, hydraulic); - characteristics of the five most activated balancing entities; - balances/imbalances accounts and production/consumption overcharge; - congestion curbing costs on the French electricity system; - energy volumes activated to ensure the balance of the system according to contracts between RTE and other Balance Responsible entities (UK, Belgium, Italy, Germany, Switzerland); - reliability of the provisional data supplied by RTE about the balancing trend; - availability of RTE's information services (planning, balancing

  20. Voltage Gain Derivation Based on Energy-Balanced Criterion for a Novel Hybrid-Input PV-Wind Power Conversion System

    Directory of Open Access Journals (Sweden)

    Chih-Lung Shen

    2015-01-01

    Full Text Available This paper applies energy-balanced criterion to a novel hybrid-input PV-wind power conversion system (HPWPCS for voltage gain derivation. With the energy-balanced concept, complicated mathematical problems related to voltage gain derivation can be readily resolved. Based on the derived results, it is proven that the proposed HPWPCS is able to process two different kinds of renewable energy resources simultaneously. Even though the HPWPCS includes seven capacitors and three magnetic components, its voltage gain still can be found by the mathematical analysis. In the theoretical derivation, only the energy status of output inductor is dealt with such that complicated derivation procedure is avoided. This analysis method can also be applied to other hybrid green-energy conversion systems. In this paper, a 200 W 50 kHz prototype of HPWPCS is built and examined to verify the mathematical results.

  1. RPL LOAD BALANCING IN INTERNET OF THINGS

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Parsaei

    2017-12-01

    Full Text Available ABSTRACT:  The wide address space provided by Internet Protocol version 6 (IPv6 lets any thing to be identified uniquely. consistency of the modified version of IPv6 protocol stack with smart objects, facilitated the Internet interconnection of the networks of smart objects and introduced Internet of things. A smart object is a small micro-electronic device that consists of a communication device, a small microprocessor and a sensor or an actuator. A network made of such devices is called low-power and lossy network. RPL routing protocol that is consistent to IPv6, is designed to be used in these kinds of networks. Load balancing is not considered in the RPL design process. Whenever RPL is used in large scale low-power and lossy networks some nodes will suffer from congestion and this problem severely degrades network performance. In this paper, we consider solutions provided to tackle RPL load balancing problems. Load balancing algorithms and protoclos are evaluated through simulation. We evaluate IETF RPL implementation and LB-RPL method with Contiki OS Java (COOJA simulator. They are assessed comprehensively through metrics such as Packet delivery Ratio, Average End to End delay, and Gateway Throughput. LB-RPL improves RPL in terms of Packet delivery Ratio and throughput but increases Average End to End delay. Simulations results show that RPL load balancing needs extensive works to be performed yet.

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

    DEFF Research Database (Denmark)

    Pillai, Jayakrishnan Radhakrishna; Bak-Jensen, Birgitte

    2009-01-01

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

  3. Nonequilibrium steady state in open quantum systems: Influence action, stochastic equation and power balance

    International Nuclear Information System (INIS)

    Hsiang, J.-T.; Hu, B.L.

    2015-01-01

    The existence and uniqueness of a steady state for nonequilibrium systems (NESS) is a fundamental subject and a main theme of research in statistical mechanics for decades. For Gaussian systems, such as a chain of classical harmonic oscillators connected at each end to a heat bath, and for classical anharmonic oscillators under specified conditions, definitive answers exist in the form of proven theorems. Answering this question for quantum many-body systems poses a challenge for the present. In this work we address this issue by deriving the stochastic equations for the reduced system with self-consistent backaction from the two baths, calculating the energy flow from one bath to the chain to the other bath, and exhibiting a power balance relation in the total (chain + baths) system which testifies to the existence of a NESS in this system at late times. Its insensitivity to the initial conditions of the chain corroborates to its uniqueness. The functional method we adopt here entails the use of the influence functional, the coarse-grained and stochastic effective actions, from which one can derive the stochastic equations and calculate the average values of physical variables in open quantum systems. This involves both taking the expectation values of quantum operators of the system and the distributional averages of stochastic variables stemming from the coarse-grained environment. This method though formal in appearance is compact and complete. It can also easily accommodate perturbative techniques and diagrammatic methods from field theory. Taken all together it provides a solid platform for carrying out systematic investigations into the nonequilibrium dynamics of open quantum systems and quantum thermodynamics. -- Highlights: •Nonequilibrium steady state (NESS) for interacting quantum many-body systems. •Derivation of stochastic equations for quantum oscillator chain with two heat baths. •Explicit calculation of the energy flow from one bath to the

  4. Analysis of the thermal balance characteristics for multiple-connected piezoelectric transformers.

    Science.gov (United States)

    Park, Joung-Hu; Cho, Bo-Hyung; Choi, Sung-Jin; Lee, Sang-Min

    2009-08-01

    Because the amount of power that a piezoelectric transformer (PT) can handle is limited, multiple connections of PTs are necessary for the power-capacity improvement of PT-applications. In the connection, thermal imbalance between the PTs should be prevented to avoid the thermal runaway of each PT. The thermal balance of the multiple-connected PTs is dominantly affected by the electrothermal characteristics of individual PTs. In this paper, the thermal balance of both parallel-parallel and parallel-series connections are analyzed by electrical model parameters. For quantitative analysis, the thermal-balance effects are estimated by the simulation of the mechanical loss ratio between the PTs. The analysis results show that with PTs of similar characteristics, the parallel-series connection has better thermal balance characteristics due to the reduced mechanical loss of the higher temperature PT. For experimental verification of the analysis, a hardware-prototype test of a Cs-Lp type 40 W adapter system with radial-vibration mode PTs has been performed.

  5. Power balance for impurity seeded ergodic divertor discharges in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Reichle, R.; Vallet, J.C.; Basiuk, V.; Chantant, M.; Giannella, R.; Guirlet, R.; Mitteau, R

    1999-10-15

    The main emphasis of the present contribution is the search for independent indications concerning local radiation enhancement in the vicinity of target plates by the application of the power-balance analysis to impurity seeded discharges and the use of spatially resolved calorimetry. All methods confirm the existence of an important local radiation enhancement in front of target objects. Their torlly localised nature and the lack of short scale toroidal resolution of the bolometers cause an underestimate of the radiation. Observed corrective factors for radiative divertor discharges range between 1.1 and 1.6 depending on the density. the impurity seeded discharges show during the impurity injection a reduction of this factor which can be explained by the radiation distribution becoming toroidally more symmetric due to larger ionisation lengths. The consistency of the results seems to validate the assumption of a fall off length of the radiation of 40 cm as used for the radiation extrapolation from the outboard calorimetry. The localised extra radiation falling onto one individual neutralizer is about 1 kW. This should be compared with spectroscopic radiation measurements and modelling to see whether there is room for charge exchange neutrals to be important. (authors)

  6. Power balance for impurity seeded ergodic divertor discharges in Tore Supra

    International Nuclear Information System (INIS)

    Reichle, R.; Vallet, J.C.; Basiuk, V.; Chantant, M.; Giannella, R.; Guirlet, R.; Mitteau, R.

    1999-01-01

    The main emphasis of the present contribution is the search for independent indications concerning local radiation enhancement in the vicinity of target plates by the application of the power-balance analysis to impurity seeded discharges and the use of spatially resolved calorimetry. All methods confirm the existence of an important local radiation enhancement in front of target objects. Their toroidally localised nature and the lack of short scale toroidal resolution of the bolometers cause an underestimate of the radiation. Observed corrective factors for radiative divertor discharges range between 1.1 and 1.6 depending on the density. the impurity seeded discharges show during the impurity injection a reduction of this factor which can be explained by the radiation distribution becoming toroidally more symmetric due to larger ionisation lengths. The consistency of the results seems to validate the assumption of a fall off length of the radiation of 40 cm as used for the radiation extrapolation from the outboard calorimetry. The localised extra radiation falling onto one individual neutralizer is about 1 kW. This should be compared with spectroscopic radiation measurements and modelling to see whether there is room for charge exchange neutrals to be important. (authors)

  7. Market based solutions for power pricing

    International Nuclear Information System (INIS)

    Wangensteen, Ivar

    2002-06-01

    The report examines how the price for effect reserves, spot market power and regulated power is formed provided ideal market conditions rule. Primarily the price determining factors in a market for power reserves are examined and how the connection between this market and the energy market (the spot market) is. In a free market there would be a balance between what the actors may obtain by operating in the open market for power reserves/regulated power on the one hand and the market for spot power on the other. Primarily we suppose that the desired amount of power reserve is known. Secondly the problem constellation is extended to comprise the size of the effect reserves i.e. the optimising of the requirement to the power reserves. The optimal amount of power reserves is obtained when there is a balance between the cost and the benefit. This optimal balance is achieved when expected macro economical loss due to outfacing balances against the cost of maintaining larger reserves. By using a simple model it is demonstrated that a system operator regulates the maximal price in the regulated market and this equals the rationing price. The actors will offer sufficient reserves even if the reserve price is zero (provided risk neutrality). If the maximal price for regulated power is lower the price of effect reserves will rise. Based on the same simple model calculations are made for how short and long term market balance will be for increasing demands

  8. The state and perspective of Belarus power engineering

    International Nuclear Information System (INIS)

    Mikhalevich, A.A.; Molochko, F.I.

    1994-01-01

    The economy of the Republic of Belarus has a high fuel and power resource deficit. In according to the National power engineering programme the power balance must be achieved by means of reconstruction and development of the energetics system on the basis of difference modern technologies, as well as carrying out power saving programme, It is suggested the building of a nuclear power plant in Belarus. The power engineering development directions for Belarus is discussed. The structure and dynamics of a power balance of the economy is described. It was shown the electric and heat energetics perspectives for Belarus by using of difference power sources. 3 tabs., 4 figs

  9. “Pivot” Toward Asia: The Strategic Direction of Russia’s Foreign Policy Concept in a Changing Balance of Powers

    Directory of Open Access Journals (Sweden)

    Elena Yu. Litsareva

    2015-04-01

    Full Text Available The article examines some reasons of the “Russia’s pivot” toward Asia at the turn of the XX-XXI centuries. The Asian policy of the Russia was starting to change at the second half of the 1990s. Russia conducted its policy at the East Asia in a view of the changed balance of national interests, regardless of the ideological considerations and attached a special importance to the economic cooperation. Developing the external political concept and determining the priority areas for development, Russia has had to reckon with the objective processes, occurring in the world. Russia, as the "Eurasian" power, building relations with the Asia-Pacific countries, was to have a vital task - to raise the political and economic cooperation with the Asia-Pacific region to the level, achieved by Russia in Europe. Gradually, the East Asia has become the priority strategic direction of the Russia positioning in the world. For a long time it was thought that using its geostrategic position, Russia could be an important factor in the global political and economic system, linking Europe and Asia-Pacific markets. Russia Federation supported the East Asia countries in ensuring regional security and stability. Analysis of the Asia-Pacific regional political situation shows that there are significant changes here and these changes are largely connected with the significant changes in the global balance of powers. In the course of the Ukrainian events (spring 2014 and entering the West economic sanctions against Russia in connection with the accession of the Crimea, Russian “pivot” toward Asia, in particular the East Asia, looks entirely justified and reasonable.

  10. Extreme prices in electricity balancing markets from an approach of statistical physics

    Science.gov (United States)

    Mureddu, Mario; Meyer-Ortmanns, Hildegard

    2018-01-01

    An increase in energy production from renewable energy sources is viewed as a crucial achievement in most industrialized countries. The higher variability of power production via renewables leads to a rise in ancillary service costs over the power system, in particular costs within the electricity balancing markets, mainly due to an increased number of extreme price spikes. This study analyzes the impact of an increased share of renewable energy sources on the behavior of price and volumes of the Italian balancing market. Starting from configurations of load and power production, which guarantee a stable performance, we implement fluctuations in the load and in renewables; in particular we artificially increase the contribution of renewables as compared to conventional power sources to cover the total load. We then determine the amount of requested energy in the balancing market and its fluctuations, which are induced by production and consumption. Within an approach of agent-based modeling we estimate the resulting energy prices and costs. While their average values turn out to be only slightly affected by an increased contribution from renewables, the probability for extreme price events is shown to increase along with undesired peaks in the costs. Our methodology provides a tool for estimating outliers in prices obtained in the energy balancing market, once data of consumption, production and their typical fluctuations are provided.

  11. Reactor primary pumps dynamic balancing test

    International Nuclear Information System (INIS)

    Lu Qunxian

    2002-01-01

    Reactor primary Pump is the important equipment in the primary circuit, its working quality would directly influence the safety and operation of nuclear power plant. The author describes that the primary pump vibration status, vibration fault diagnosis and dynamic balancing process on site have been performed since commercial operation of DA YA BAY Nuclear Power plant

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

    International Nuclear Information System (INIS)

    Tande, John Olav

    2006-04-01

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

  13. Coil motion effects in watt balances: a theoretical check

    Science.gov (United States)

    Li, Shisong; Schlamminger, Stephan; Haddad, Darine; Seifert, Frank; Chao, Leon; Pratt, Jon R.

    2016-04-01

    A watt balance is a precision apparatus for the measurement of the Planck constant that has been proposed as a primary method for realizing the unit of mass in a revised International System of Units. In contrast to an ampere balance, which was historically used to realize the unit of current in terms of the kilogram, the watt balance relates electrical and mechanical units through a virtual power measurement and has far greater precision. However, because the virtual power measurement requires the execution of a prescribed motion of a coil in a fixed magnetic field, systematic errors introduced by horizontal and rotational deviations of the coil from its prescribed path will compromise the accuracy. We model these potential errors using an analysis that accounts for the fringing field in the magnet, creating a framework for assessing the impact of this class of errors on the uncertainty of watt balance results.

  14. Effects of over-the-counter jaw-repositioning mouth guards on dynamic balance, flexibility, agility, strength, and power in college-aged male athletes.

    Science.gov (United States)

    Golem, Devon L; Arent, Shawn M

    2015-02-01

    Improvements in muscular power and anaerobic performance have resulted from the use of jaw-repositioning mouth guards designed with advanced dental techniques. The high cost of such techniques has dissuaded the widespread use. Recently, more affordable, over-the-counter (OTC) jaw-repositioning mouth guards have become available. The primary objective of this study was to examine the effects of 2 OTC jaw-repositioning mouth guards on muscular power and strength performance in college-aged male athletes. It was hypothesized that similar to previous observations with advanced dentistry-designed mouth guards, OTC jaw-repositioning mouth guards would impart positive effects on muscular power but not have any effect on muscular strength. Secondary objectives of this study included the examination of the effects of 2 OTC jaw-repositioning mouth guards on other variables related to athletic performance. Male collegiate athletes (N = 20) participated in 4 separate testing sessions that consisted of assessment of muscular power, dynamic balance, flexibility, agility, and muscular strength. The 4 conditions, 1 per testing session, were assigned in a randomized order and consisted of a no-mouth guard control (CON), a placebo mouth guard, a self-adapted jaw-repositioning mouth guard (SA), and a custom-fitted jaw-repositioning mouth guard (CF). No significant differences were observed between conditions in muscular power (p = 0.78), dynamic balance (p = 0.99), agility (p = 0.22), or muscular strength (p = 0.47). The CF had significantly lower hip flexion than the CON (p = 0.014) and had significantly greater lumbar spine lateral flexion compared with the SA condition (p = 0.054). However, these flexibility differences lack practical relevance as the effect sizes remain very small (ES = -0.27 and -0.14, respectively). In conclusion, the jaw-repositioning technique used in the design of these OTC mouth guards did not affect performance. It is important to note that negative

  15. Simple Cell Balance Circuit

    Science.gov (United States)

    Johnson, Steven D.; Byers, Jerry W.; Martin, James A.

    2012-01-01

    A method has been developed for continuous cell voltage balancing for rechargeable batteries (e.g. lithium ion batteries). A resistor divider chain is provided that generates a set of voltages representing the ideal cell voltage (the voltage of each cell should be as if the cells were perfectly balanced). An operational amplifier circuit with an added current buffer stage generates the ideal voltage with a very high degree of accuracy, using the concept of negative feedback. The ideal voltages are each connected to the corresponding cell through a current- limiting resistance. Over time, having the cell connected to the ideal voltage provides a balancing current that moves the cell voltage very close to that ideal level. In effect, it adjusts the current of each cell during charging, discharging, and standby periods to force the cell voltages to be equal to the ideal voltages generated by the resistor divider. The device also includes solid-state switches that disconnect the circuit from the battery so that it will not discharge the battery during storage. This solution requires relatively few parts and is, therefore, of lower cost and of increased reliability due to the fewer failure modes. Additionally, this design uses very little power. A preliminary model predicts a power usage of 0.18 W for an 8-cell battery. This approach is applicable to a wide range of battery capacities and voltages.

  16. Improving Current Balance In Parallel MOSFET's

    Science.gov (United States)

    Niedra, Janis M.

    1992-01-01

    Simple circuit makes currents more nearly equal. Addition of diodes and adjustable-tap resistor increases operating range over which drain currents in two unmatched power MOSFET's brought more nearly into balance.

  17. Autonomous power networks based power system

    International Nuclear Information System (INIS)

    Jokic, A.; Van den Bosch, P.P.J.

    2006-01-01

    This paper presented the concept of autonomous networks to cope with this increased complexity in power systems while enhancing market-based operation. The operation of future power systems will be more challenging and demanding than present systems because of increased uncertainties, less inertia in the system, replacement of centralized coordinating activities by decentralized parties and the reliance on dynamic markets for both power balancing and system reliability. An autonomous network includes the aggregation of networked producers and consumers in a relatively small area with respect to the overall system. The operation of an autonomous network is coordinated and controlled with one central unit acting as an interface between internal producers/consumers and the rest of the power system. In this study, the power balance problem and system reliability through provision of ancillary services was formulated as an optimization problem for the overall autonomous networks based power system. This paper described the simulation of an optimal autonomous network dispatching in day ahead markets, based on predicted spot prices for real power, and two ancillary services. It was concluded that large changes occur in a power systems structure and operation, most of them adding to the uncertainty and complexity of the system. The introduced concept of an autonomous power network-based power system was shown to be a realistic and consistent approach to formulate and operate a market-based dispatch of both power and ancillary services. 9 refs., 4 figs

  18. Effects of feedback-based balance and core resistance training vs. Pilates training on balance and muscle function in older women: a randomized-controlled trial.

    Science.gov (United States)

    Markovic, Goran; Sarabon, Nejc; Greblo, Zrinka; Krizanic, Valerija

    2015-01-01

    Aging is associated with decline in physical function that could result in the development of physical impairment and disability. Hence, interventions that simultaneously challenge balance ability, trunk (core) and extremity strength of older adults could be particularly effective in preserving and enhancing these physical functions. The purpose of this study was to compare the effects of feedback-based balance and core resistance training utilizing the a special computer-controlled device (Huber®) with the conventional Pilates training on balance ability, neuromuscular function and body composition of healthy older women. Thirty-four older women (age: 70±4 years) were randomly assigned to a Huber group (n=17) or Pilates group (n=17). Both groups trained for 8 weeks, 3 times a week. Maximal isometric strength of the trunk flexors, extensors, and lateral flexors, leg power, upper-body strength, single- and dual-task static balance, and body composition were measured before and after the intervention programs. Significant group×time interactions and main effects of time (pcore resistance training proved to be more effective in improving single- and dual-task balance ability, trunk muscle strength, leg power, and body composition of healthy older women than the traditional Pilates training. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Energy balance of hydro-aggregate with Pelton water turbine

    International Nuclear Information System (INIS)

    Obretenov, V.

    2005-01-01

    One of the major tasks in the field of hydraulic power engineering refers to machines and equipment modernization in the hydropower plants and pumped storage power plants commissioned more than 20 years ago. The increase of hydraulic units operation efficiency will allow in a number of cases to substantially reduce the specific water consumption and to drive the output of electric energy up. In these cases it is crucial to find out the operational efficiency of individual system elements and to precisely focus the modernization endeavours on such elements where the energy losses go beyond all admissible limits. Besides, the determination of the energy losses in the hydro energy turbo system will allow valid defining of hydraulic units operational scope. This work treats the methods of balance study of a hydraulic unit with Peiton water turbine. The experimental results of the balance study of Belmeken pumped storage power plant hydraulic unit No 5 under turbine operational mode are presented

  20. Mix of power system flexibility means providing 50 % wind power penetration in the Danish power system in 2030

    DEFF Research Database (Denmark)

    Nørgård, Per Bromand; Lund, H.; Mathiesen, B.V.

    2008-01-01

    Time series simulations of an example of a realistic modified energy system in Denmark 2030, assuming no internal power transmission bottlenecks, indicates that it is both technical possible and economic feasible to maintain the energy balance on hourly basis, even with a wind power penetration...

  1. Energy balances of OECD countries 1970/1982

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    The present volume provides standardized energy balance sheets expressed in a common unit of tons of oil equivalent for all OECD Countries. It covers the years 1970 to 1982 year by year and includes many revisions and additions to data previously published. The balances in the present volume are based on data published in OECD Energy Statistics 1971-1981 and OECD Energy Statistics 1981-1982. Tables for each OECD Country include production, import, export, consumption by the different industries, transportation, agriculture, residential sector of the different energies: solid fuels, petroleum, gas, nuclear power and hydroelectricity [fr

  2. C2 Lithium Campaign Power Balance

    Science.gov (United States)

    Trask, Erik; Deng, Bihe; Douglass, Jon; Garate, Eusebio; Gupta, Deepak; Gupta, Sangeeta; Tuszewski, Michel; TAE Team

    2014-10-01

    Several key changes have lead to record performance of the Tri Alpha Energy's (TAE) C2 Field Reversed Configuration (FRC) device. Wall conditioning changes from titanium to lithium have decreased radiative losses, while changes in the magnetic field of the SOL and jet have substantially increased energy confinement times. An overview of 0D power flows and timescales will be presented demonstrating that ions behave classically, that anomalous electron losses have been substantially reduced, and that plasma sustainment will require modest increases in heating power. These observations will be quantitatively analyzed as well as compared with both theoretical modeling of the TAE transport and numerical simulations (Q2D).

  3. Power Generation and Distribution via Distributed Coordination Control

    OpenAIRE

    Kim, Byeong-Yeon; Oh, Kwang-Kyo; Ahn, Hyo-Sung

    2014-01-01

    This paper presents power coordination, power generation, and power flow control schemes for supply-demand balance in distributed grid networks. Consensus schemes using only local information are employed to generate power coordination, power generation and power flow control signals. For the supply-demand balance, it is required to determine the amount of power needed at each distributed power node. Also due to the different power generation capacities of each power node, coordination of pow...

  4. Analysis Methodology for Balancing Authority Cooperation in High Penetration of Variable Generation

    Energy Technology Data Exchange (ETDEWEB)

    Makarov, Yuri V.; Etingov, Pavel V.; Zhou, Ning; Ma, Jian; Samaan, Nader A.; Diao, Ruisheng; Malhara, Sunita V.; Guttromson, Ross T.; Du, Pengwei; Sastry, Chellury

    2010-02-01

    With the rapidly growing penetration level of wind and solar generation, the challenges of managing variability and the uncertainty of intermittent renewable generation become more and more significant. The problem of power variability and uncertainty gets exacerbated when each balancing authority (BA) works locally and separately to balance its own subsystem. The virtual BA concept means various forms of collaboration between individual BAs must manage power variability and uncertainty. The virtual BA will have a wide area control capability in managing its operational balancing requirements in different time frames. This coordination results in the improvement of efficiency and reliability of power system operation while facilitating the high level integration of green, intermittent energy resources. Several strategies for virtual BA implementation, such as ACE diversity interchange (ADI), wind only BA, BA consolidation, dynamic scheduling, regulation and load following sharing, extreme event impact study are discussed in this report. The objective of such strategies is to allow individual BAs within a large power grid to help each other deal with power variability. Innovative methods have been developed to simulate the balancing operation of BAs. These methods evaluate the BA operation through a number of metrics — such as capacity, ramp rate, ramp duration, energy and cycling requirements — to evaluate the performances of different virtual BA strategies. The report builds a systematic framework for evaluating BA consolidation and coordination. Results for case studies show that significant economic and reliability benefits can be gained. The merits and limitation of each virtual BA strategy are investigated. The report provides guidelines for the power industry to evaluate the coordination or consolidation method. The application of the developed strategies in cooperation with several regional BAs is in progress for several off-spring projects.

  5. French electric power balance sheet and RTE's technical results for 2004

    International Nuclear Information System (INIS)

    Derdevet, Michel; Lartigau, Thierry; Coutier, Isabelle

    2005-01-01

    The mission of RTE, the French electricity Transportation grid, a public service assignment, is to balance the electricity supply and demand in real time. This report presents RTE's preliminary technical results for the year 2004: key figures of the electricity balance sheet, market development, infrastructures performance and evolution, environmental aspects. A second part is devoted to a presentation of the actors of the electricity market, while a third part presents the results of the 2004 RTE's clients survey

  6. Cost of nuclear power generation judged by power rate

    International Nuclear Information System (INIS)

    Hirai, Takaharu

    1981-01-01

    According to estimation guidance, power rates in general are the proper cost plus the specific compensation and adjustment addition. However, the current system of power rates is of power-source development promotion type involving its tax. The structure of power rate determination must be restudied now especially in connection of nuclear power generation. The cost of nuclear power generation as viewed from power rate is discussed as follows: the fear of military application of power plants, rising plant construction costs, the loophole in fuel cost calculation, unreasonable unit power cost, depreciation and repair cost, business compensation, undue business compensation in nuclear power, the costs of nuclear waste management, doubt concerning nuclear power cost, personnel, pumping-up and power transmission costs in nuclear power, energy balance analysis, nuclear power viewed in entropy, the suppression of power consumption. (J.P.N.)

  7. India and the BRICS: Global Bandwagoning and Regional Balancing

    Directory of Open Access Journals (Sweden)

    Matthew D Stephen

    2016-12-01

    Full Text Available Indian policy makers have welcomed India’s framing as a ‘rising power’ and celebrated the BRICS initiative as a common front in reforming aspects of global governance. Yet China’s rise in Asia has unsettled the balances of power which have underpinned the region, as a consequence of which India has hesitantly pursued a strategic rapprochement with the United States. Assessing New Delhi’s multilateral and geo-strategic diplomacy, this article argues that India bandwagons with the BRICS on a global level, but seeks to balance China at the regional level. On the global multilateral level, India has common cause with other rising powers in reforming the policies and structures of most international organizations. The exceptions are the United Nations Security Council and the Non-proliferation Treaty, where China and Russia can be qualified as established powers. On the regional level, however, India has maintained ties to Russia and cultivated a strong relationship with the United States in an effort to balance and increase leverage relative to a rising China. This underlines that major power rivalries are strongly mediated by issue area and institutional context.

  8. Impacts of large amounts of wind power on design and operation of power systems, results of IEA collaboration

    DEFF Research Database (Denmark)

    Holttinen, Hannele; Meibom, Peter; Orths, Antje

    2011-01-01

    There are dozens of studies made and ongoing related to wind integration. However, the results are not easy to compare. IEA WIND R&D Task 25 on Design and Operation of Power Systems with Large Amounts of Wind Power collects and shares information on wind generation impacts on power systems......, with analyses and guidelines on methodologies. In the state-of-the-art report (October, 2007), and the final report of the 3 years period (July, 2009) the most relevant wind power grid integration studies have been analysed especially regarding methodologies and input data. Several issues that impact...... on the amount of wind power that can be integrated have been identified. Large balancing areas and aggregation benefits of wide areas help in reducing the variability and forecast errors of wind power as well as help in pooling more cost effective balancing resources. System operation and functioning...

  9. Joint balance handling in the Nordic Countries

    International Nuclear Information System (INIS)

    2005-01-01

    In September 2002 Nordel introduced new principles for disposing of regulation power for balancing production and consumption of electricity. The new principles imply that the regulation power in the joint Nordic power system is better utilized, and that the settlement of imbalances between the countries follows joint rules. The settlement of imbalances in the individual countries follows different principles but Nordel is looking into the possibilities of a harmonization. EU's most recent draft of a strategy report on development of the power market points among other things towards a joint regulation power market as a tool against misuse of market power. (BA)

  10. Operational management of intraday and balancing markets. A survey

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Jeanne [Aarhus Univ. (Denmark). Dept. of Economics and Business, Business and Social Sciences; Detlefsen, Nina K. [Energinet.dk, Fredericia (Denmark). Systems Analysis

    2011-07-01

    Lately, there has been increased attention on the challenges that will appear when balancing the electricity in the future and the benefits of integrated markets between countries and regions. This is among other things due to the fact that electricity markets in the future will experience major changes and challenges, which may be better addressed with closer collaboration. In order to evaluate the benefits of cross-border balancing, it is essential to have an understanding of the mechanisms and operations of the European markets and how they interact. Therefore, this paper aims at describing electricity markets in Europe: day-ahead markets and markets with shorter time spans. The focus will be on balancing markets and how these are used operationally. The most promising theoretical models found in the literature with applications to balancing will be presented. The purpose of this is to identify the tools necessary to analyze future balancing of power systems. (orig.)

  11. Partial Key Grouping: Load-Balanced Partitioning of Distributed Streams

    OpenAIRE

    Nasir, Muhammad Anis Uddin; Morales, Gianmarco De Francisci; Garcia-Soriano, David; Kourtellis, Nicolas; Serafini, Marco

    2015-01-01

    We study the problem of load balancing in distributed stream processing engines, which is exacerbated in the presence of skew. We introduce PARTIAL KEY GROUPING (PKG), a new stream partitioning scheme that adapts the classical “power of two choices” to a distributed streaming setting by leveraging two novel techniques: key splitting and local load estimation. In so doing, it achieves better load balancing than key grouping while being more scalable than shuffle grouping. We test PKG on severa...

  12. Angra-1: Balance of an experience

    International Nuclear Information System (INIS)

    Salvo Brito, S. de

    1985-01-01

    An evaluation of experience got during the construction of Angra-1 nuclear power plant which had built by FURNAS CENTRAIS ELETRICAS S.A. is done. It is analyzed the problems in level of management, including technology transfer. A balance of the real costs and benefits from the definition of the specifications to energy generation is done. (M.C.K.) [pt

  13. The impact of microgeneration upon the Dutch balancing market

    International Nuclear Information System (INIS)

    Van der Veen, Reinier A.C.; De Vries, Laurens J.

    2009-01-01

    The share of microgeneration (power generation at the level of households and small businesses) in the Dutch electricity system continues to grow. Over time, this development may pose a threat to the reliability and efficiency of the Dutch electricity balancing market. We investigated possible changes to the design of the Dutch balancing market that can maintain or even improve upon its current operational performance level. The first step of the research was an analysis of the existing Dutch balancing market. It consists of three main instruments: programme responsibility, the single buyer market for regulating and reserve power (RRP), and imbalance settlement. The balancing market currently functions satisfactorily. Subsequently, the effects of large-scale development of microgeneration in the Netherlands were evaluated with a qualitative scenario analysis. Four microgeneration scenarios and two methods for allocating the household electricity consumption and generation were considered. The four scenarios concerned large-scale penetration of PV, heat-led micro CHP, electricity-led micro CHP operated by the household consumer, and electricity-led micro CHP operated by the supply company. The last scenario was found to have the strongest positive net effect. Finally, six design options were identified for improving the Dutch balancing market design in case the share of microgeneration would increase substantially. Of these six options, adjusting the profile methodology and the regulation of smart meters are no-regret options that can be implemented immediately. The attractiveness of the other options depends upon the microgeneration portfolio that emerges, the manageability of large metering data flows, and the nature of the technical effects of large-scale microgeneration penetration.

  14. Nonlinear Distortion Mechanisms and Efficiency of Balanced-Armature Loudspeakers

    DEFF Research Database (Denmark)

    Jensen, Joe

    are inherently nonlinear devices, since any displacement of the loudspeaker diaphragm in- evitably changes the magnetic and electrical characteristics of the loudspeaker. Additionally, for the balanced-armature loudspeaker the signal has to be transmitted through the magnetic domain (as a magnetic B -field...... and to validate simpler equivalent circuit models. A large scale model of a balanced-armature loudspeaker has been developed and its inherent nonlinear parameters have been measured and compared to the theoretically predicted values. A measurement setup for determining the magnetic properties of soft magnetic...... materials has also been developed, since it is of great importance to understand what kind of linear and nonlinear transformations the magnetic materials impose on the signal. In hearing aid applications the power efficiency of the loudspeaker is important because every reduction in power consumption...

  15. Price-based control of ancillary services for power balancing

    NARCIS (Netherlands)

    Bosch, van den P.P.J.; Jokic, A.; Frunt, J.; Kling, W.L.; Nobel, Frank; Boonekamp, P.; Boer, de W.; Hermans, R.M.; Virag, A.

    2011-01-01

    A reliable and an efficient power system is a necessity for any industrialized society. Governments have to enforce regulations to guarantee that such a power system, in spite of many competing stakeholders, participants, companies, and regulating agencies can be operational. This paper analyzes the

  16. Nuclear blackmail and nuclear balance

    International Nuclear Information System (INIS)

    Betts, R.K.

    1987-01-01

    This book raises pointed questions about nuclear saber rattling. More than a dozen cases since the bombing of Hiroshima and Magasaki in which some sort of nuclear threat was used as a sparring technique in tense confrontations are cited. Each incident is described and analyzed. Two theories offered to explain America's use of nuclear threats, the balance of interest theory and the balance of power theory, are contrasted throughout the book. This book helps to fill the gap in the understanding of nuclear weapons and their uses, while pointing out that nuclear bravado could lead to an unintended unleashing of these weapons

  17. General Influence Coefficient Algorithm in Balancing of Rotating Machinery

    Directory of Open Access Journals (Sweden)

    Xiaoping Yu

    2004-01-01

    Full Text Available The General Influence Coefficient Algorithm (GICA, developed in this article, is a new calculation method for Influence Coefficients (ICs with a general formula. Compared to the traditional calculation method, GICA can solve the ICs' calculation task when the group of trial weights are installed on the rotor each time, the trial weights are retained on the rotor systems, or there is redundant trial balancing data, when even part of the ICs is known. GICA is also a powerful tool for refining the ICs from redundant balancing data or historical balancing data and serves as a general algorithm. With the general matrix formula, GICA is ready to be applied in a computer-aided balancing system as the key part of calculation software. Examples in industry are also presented to demonstrate the aplication of this new algorithm.

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

    DEFF Research Database (Denmark)

    Farashbashi-Astaneh, Seyed-Mostafa

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

  19. System analysis and mass balance of a caloric power plant

    International Nuclear Information System (INIS)

    Schachermayer, E.; Rechberger, H.; Brunner, P.H.; Maderner, W.

    1995-05-01

    The present feasibility study analyses the possibilities of examining and presenting material and energy aspects of the interaction between the power plant and the region. A method has been worked out to establish an overall system called power plant and its periphery which combines the thermal power plant Voitsberg 3, the supplying coal mine Oberdorf, and the ash dumping site Karlschacht 2. One goal of this study was therefore, to find a way of combining the different steps 'mining' , 'power plant' , and 'ash dumping' to an overall system considering both qualitative and quantitative aspects. Another goal of the present feasibility study was to develop methods to consider the impacts of the power plant and its periphery to the environment and the use of resources. For this purpose the region is analysed from two different points of view: - the region defined by the 'product'; its size is defined by the number of inhabitants the power plant supplies with the product 'electricity'. The region defined by the area, in which the specific impacts of the power plant on air, water, soil etc. have to be examined; its size will therefore vary considerably according to the subject of investigation. Based on data provided by the power plant operators a rough estimate could be made to what extent the power plant is responsible for the air pollutant emissions in the region defined by the 'product'. According to these data the part of pollution caused by the power plant amounts to 10% for NOx and particulate matter, to 40% for SO 2 , and to 70% for CO 2 . Furthermore, it can be seen, that the material fluxes of selenium and mercury have to be surveyed in more detail. The ashes dumped in Karlschacht 2 contain a large amount of heavy metals, mainly arsenic, selenium, and mercury. These elements occur in a much higher concentration than in the earth crust. (author)

  20. Storage and balancing synergies in a fully or highly renewable pan-European power system

    DEFF Research Database (Denmark)

    Rasmussen, Morten Grud; Bruun Andresen, Gorm; Greiner, Martin

    2012-01-01

    the balancing energy needs for a given storage size, the interplay between storage and balancing is quantified, providing a hard upper limit on their synergy. An efficient but relatively small storage reduces balancing energy needs significantly due to its influence on intra-day mismatches. Furthermore, we show...

  1. On the diversity enhancement and power balancing of per-subcarrier antenna selection in OFDM systems

    KAUST Repository

    Park, Kihong; Ko, Youngchai; Alouini, Mohamed-Slim

    2010-01-01

    In this paper, we consider multi-carrier systems with multiple transmit antennas under a power balancing constraint. Applying transmit antenna selection and discrete rate adaptive modulation using M-ary quadrature amplitude modulation (QAM) according to the channel variation per subcarrier, we develop an optimal antenna selection scheme in terms of maximum spectral efficiency where all the possible grouping to send the same information bearing signals in a group of subcarriers are searched and the groups of subcarriers to provide the frequency diversity gain are formed. In addition, we propose a suboptimal method to reduce the computational complexity of the optimal method. The suboptimal scheme consider only the subcarriers under outage and those are combined sequentially until it meets a required SNR. Numerical results show that the proposed suboptimal method with diversity combining outperforms the optimal antenna selection without diversity combining introduced in [1], especially for low SNR region and offers the spectral efficiency close to that of the optimal method with diversity combining, while maintaining lower complexity. ©2010 IEEE.

  2. On the diversity enhancement and power balancing of per-subcarrier antenna selection in OFDM systems

    KAUST Repository

    Park, Kihong

    2010-09-01

    In this paper, we consider multi-carrier systems with multiple transmit antennas under a power balancing constraint. Applying transmit antenna selection and discrete rate adaptive modulation using M-ary quadrature amplitude modulation (QAM) according to the channel variation per subcarrier, we develop an optimal antenna selection scheme in terms of maximum spectral efficiency where all the possible grouping to send the same information bearing signals in a group of subcarriers are searched and the groups of subcarriers to provide the frequency diversity gain are formed. In addition, we propose a suboptimal method to reduce the computational complexity of the optimal method. The suboptimal scheme consider only the subcarriers under outage and those are combined sequentially until it meets a required SNR. Numerical results show that the proposed suboptimal method with diversity combining outperforms the optimal antenna selection without diversity combining introduced in [1], especially for low SNR region and offers the spectral efficiency close to that of the optimal method with diversity combining, while maintaining lower complexity. ©2010 IEEE.

  3. The Future of Economic Power

    OpenAIRE

    Malanciuc Bogdan Simion

    2014-01-01

    The importance of power in the development of society is undeniable. The power relations between national economies are more and more important and should be considered in every international economics analysis. Economic power has become the bedrock of both the military and the political power. Today the balance of economic power is shifting. The emerging states (China in the first place) are now demanding a greater role in global politics, challenging the existing international order dominat...

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

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  5. Separation of Powers and the Legislative Power.

    Science.gov (United States)

    Rossum, Ralph A.

    1986-01-01

    Addresses the contribution of separation of powers and checks and balances in resolving the rival defects of democratic ineptitude and majority tyranny as the Founders framed the Constitution. Contends the Founders structured the government so that the three branches could keep each other in their proper places. Discusses Anti- Federalist…

  6. Droop-Control-Based State-of-Charge Balancing Method for Charging and Discharging Process in Autonomous DC Microgrids

    DEFF Research Database (Denmark)

    Lu, Xiaonan; Sun, Kai; Guerrero, Josep M.

    2014-01-01

    in the discharging process. Meanwhile, the ESU with lower SoC absorbs more power in the charging process and delivers less power in the discharging process. Eventually, the SoC and injected/output power in each ESU are equalized. The exponent n for SoC is employed to regulate the balancing speed of the So......C and injected/output power. It is demonstrated that with higher exponent n, the balancing speed is higher. Simulation model comprised of three ESUs is implemented by using MATLAB/Simulink. The proposed method is verified by the simulation results....

  7. Assessment and balancing of nuclear fuels

    International Nuclear Information System (INIS)

    Reinhard, H.

    1982-01-01

    In 1981 nuclear energy had a share of ca. 17% in the electric power supply of the F.R. of Germany. The amount of nuclear fuels required is equal to ca. 15 million tce. In public technical discussions the economic importance which must be assigned to nuclear energy, e.g. with regard to curbing the energy price development or relieving our balance of payments, is discussed in detail. On the other hand, a number of industrial aspects of nuclear energy utilization - problems of commercial or fiscal law - have been little considered in the technical literature. The following contribution is to present the principles of commercial and fiscal law which have taken shape in connection with the assessment and balancing of the single stages of the nuclear fuel cycle. (orig./UA) [de

  8. Balance Performance During Perturbed Standing Is Not Associated With Muscle Strength and Power in Young Adults.

    Science.gov (United States)

    Zemková, Erika; Jeleň, Michal; Kováčiková, Zuzana; Miklovič, Peter; Svoboda, Zdeněk; Janura, Miroslav

    2017-01-01

    The authors investigate the ways in which varied postural responses to translating platform perturbations are associated with the variables of strength and power. Twenty-four physically active and 27 sedentary young adults were exposed to a set of postural perturbations at varied velocities (10 and 20 cm/s) and the respective accelerations (6.4 and 6.9 m/s 2 ), constant distance (6 cm), and 4 directions of platform motion (forward, backward, left-lateral, and right-lateral). They also performed maximum voluntary isometric contraction (MVC) and chair rising/chair jumping tests. The analysis of variance revealed significant interaction effect for peak center of pressure displacement, direction by velocity: F 3,129 = 24.43, p = .002; and direction by acceleration: F 3,129 = 34.18, p = .001. There were no significant correlations between peak center of pressure displacements and peak force and peak rate of force development measured during MVC in either standing (r = .27-57) or sitting positions (r = .12-51) and peak power during chair jumping (r = .47-.59) in all participants. As such, only a small proportion of variance was explained (9-39%, 3-23%, and 23-41%, respectively). In conclusion, interaction effects indicate that the composition of stimuli strongly influences compensatory responses and this effect is more pronounced in sedentary than in physically active young adults. Nevertheless, the dynamic balance is not associated with muscle strength and power in either group.

  9. Shifting the Balance: Relationship as Power in Organizational Life.

    Science.gov (United States)

    Davidson, Sandra J

    2015-01-01

    Power has traditionally been studied and experienced within organizations from a hierarchical and positivist perspective. However, organizational complexity has never been greater, and in our attempts to find new ways to live amid this complexity we seek alternative theoretical perspectives that may better represent and inform our experiences of organizational life. This article summarizes the positivist view of power within organizations and the limitations of attempting to study power from this perspective. Power is then reconceptualized and explored using the complex responsive process (CRP) analysis. This is an exemplar of how narrative inquiry guided by CRP may be used as a frame for reflexivity and reflection amid organizational power dynamics. The narrative description used in this paper was based on the author's experience and reflection upon a nursing faculty meeting in a large public university. By becoming aware of the power relations in which we engage, and by reflecting upon them using CRP, we may come to understand power relations in a different way. In the act of examining and reflecting on our habitual roles in power relations, we may open up the potential for personal and organizational transformation. © 2015 Wiley Periodicals, Inc.

  10. Measurement of ultrasound power using a calorimeter

    Science.gov (United States)

    Morgado, G.; Miqueleti, S.; Costa-Felix, R. P. B.

    2018-03-01

    This paper presents a comparison between the ultrasound power of a 1 MHz therapy equipment on the water using a calorimeter and a radiation force balance. For a range of 5 to 10 W, the results presented a normalized error less than 1, disclosing compatibility of the results from the developed system and the radiation force balance. The calorimetric method might be used as a faster and cheaper means for the verification of the ultrasonic power emitted by an equipment for physiotherapeutic treatment.

  11. The The Effects of Cold Water Immersion on Anaerobic Power, Dynamic Balance and Muscle Activation After a karate kumite fighting in Female Karateka

    Directory of Open Access Journals (Sweden)

    Taher Afshar Nezhad

    2017-10-01

    Full Text Available Many athletes are using specific techniques to minimize fatigue and accelerate recovery processes. Cold water immersion (CWI is one of the most popular interventions used by athletes to potentially return to their pre-fatigue performance level. the purpose of this study was to investigate the effects of CWI on anaerobic performance, balance and muscle activation of female karateka after a simulated match. 15 young female karateka (age: 18.7±1.7 years, body mass: 55.5±6.3 kg, height:165±5.1 cm with at least three years' experience in karate kumite fighting were included in the study. After three round 3-minute competition, participants were grouped into a CWI group (20 min at 12±1°C and a control group (CTL. Anaerobic power (30 s Wingate test, and dynamic balance (Star-Excursion test were measured before the competition and 24 h after intervention. Surface electromyography (EMG was sampled from quadriceps femoris muscles. Peak normalized muscle activation levels and force were identified during maximal isometric test. A significant decrease in the anaerobic performance after the competition was observed for both groups (p<0.05. CWI were effective in enhancing the anaerobic performance after competition compared with the CTL. Dynamic balance decreased for two groups, although CWI resulted in the smallest reduction in balance. There was a significant difference in peak and mean RMS values of the EMG in Rectus Femoris but not Vastus muscles after the CWI intervention when compared to CTL (p<0.05. CWI improve recovery related to dynamic balance and anaerobic performance of karate kumite fighter. It can be concluded that CWI appears to promote muscle activation and reduce fatigue that is related to better performance in 24 hours post intervention.

  12. Mathematical models and methods for analysis of distributed power generation on market conditions

    DEFF Research Database (Denmark)

    Schaumburg-Müller, Camilla

    2008-01-01

    day and a common hourly electricity spot price is found. Intra-day markets for balancing power also exist. The raison d’etre for this type of market is that although supply and demand are balanced on a day-ahead basis, actual demand is impossible to forecast with complete accuracy. Thus on the day...... of operation actual demand and planned supply never match precisely. The system operator must then procure so-called balancing power in the intra-day market to maintain the physical balance of the system at all times. The present thesis considers the effects of large amounts of distributed electricity...... in advance as opposed to purchasing the needed volumes in the intra-day balancing market. The thesis itself provides an introduction to the Nordic power system and market with emphasis on the Danish situation. After presenting a few classic topics in power system operation, the situation post...

  13. Adaptive control of dynamic balance in human gait on a split-belt treadmill.

    Science.gov (United States)

    Buurke, Tom J W; Lamoth, Claudine J C; Vervoort, Danique; van der Woude, Lucas H V; den Otter, Rob

    2018-05-17

    Human bipedal gait is inherently unstable and staying upright requires adaptive control of dynamic balance. Little is known about adaptive control of dynamic balance in reaction to long-term, continuous perturbations. We examined how dynamic balance control adapts to a continuous perturbation in gait, by letting people walk faster with one leg than the other on a treadmill with two belts (i.e. split-belt walking). In addition, we assessed whether changes in mediolateral dynamic balance control coincide with changes in energy use during split-belt adaptation. In nine minutes of split-belt gait, mediolateral margins of stability and mediolateral foot roll-off changed during adaptation to the imposed gait asymmetry, especially on the fast side, and returned to baseline during washout. Interestingly, no changes in mediolateral foot placement (i.e. step width) were found during split-belt adaptation. Furthermore, the initial margin of stability and subsequent mediolateral foot roll-off were strongly coupled to maintain mediolateral dynamic balance throughout the gait cycle. Consistent with previous results net metabolic power was reduced during split-belt adaptation, but changes in mediolateral dynamic balance control were not correlated with the reduction of net metabolic power during split-belt adaptation. Overall, this study has shown that a complementary mechanism of relative foot positioning and mediolateral foot roll-off adapts to continuously imposed gait asymmetry to maintain dynamic balance in human bipedal gait. © 2018. Published by The Company of Biologists Ltd.

  14. Pragmatic power

    CERN Document Server

    Eccles, William

    2008-01-01

    Pragmatic Power is focused on just three aspects of the AC electrical power system that supplies and moves the vast majority of electrical energy nearly everywhere in the world: three-phase power systems, transformers, and induction motors. The reader needs to have had an introduction to electrical circuits and AC power, although the text begins with a review of the basics of AC power. Balanced three-phase systems are studied by developing their single-phase equivalents. The study includes a look at how the cost of ""power"" is affected by reactive power and power factor. Transformers are cons

  15. Reactivity balance for a soluble boron-free small modular reactor

    Directory of Open Access Journals (Sweden)

    Lezani van der Merwe

    2018-06-01

    Full Text Available Elimination of soluble boron from reactor design eliminates boron-induced reactivity accidents and leads to a more negative moderator temperature coefficient. However, a large negative moderator temperature coefficient can lead to large reactivity feedback that could allow the reactor to return to power when it cools down from hot full power to cold zero power. In soluble boron-free small modular reactor (SMR design, only control rods are available to control such rapid core transient.The purpose of this study is to investigate whether an SMR would have enough control rod worth to compensate for large reactivity feedback. The investigation begins with classification of reactivity and completes an analysis of the reactivity balance in each reactor state for the SMR model.The control rod worth requirement obtained from the reactivity balance is a minimum control rod worth to maintain the reactor critical during the whole cycle. The minimum available rod worth must be larger than the control rod worth requirement to manipulate the reactor safely in each reactor state. It is found that the SMR does have enough control rod worth available during rapid transient to maintain the SMR at subcritical below k-effectives of 0.99 for both hot zero power and cold zero power. Keywords: Control Rod Worth, Reactivity Balance, Reactivity Feedback, Small Modular Reactor, Soluble Boron Free

  16. Balancing the supply mix to meet tomorrow's energy needs

    International Nuclear Information System (INIS)

    Wiggin, M.

    2004-01-01

    This presentation emphasized the need to balance the power supply mix to ensure future energy needs. A balanced supply includes generation supply options that include renewable energy sources, natural gas, oil or coal. The role of combined heat and power (CHP) and district energy in this supply mix is considered to be a potential generation solution. The challenge facing Ontario's Independent Electricity Market Operator (IMO) is to balance supply and demand, phase out coal, promote renewables, diminish demand and determine the new role for natural gas. A graph by the National Energy Board depicting Canada's energy future and scenarios for supply and demand to 2025 indicates that gas yields from the Western Canada Sedimentary Basin are declining. It is expected that with growing demands for natural gas, prices will remain high and there will be a need for new generation capacity. The viable options for energy supply include a re-examination of the district energy advantage through industrial waste heat, biomass and other renewables, and the integration of industrial and community energy systems. Other options include the continued recognition of distributed generation in the form of combined heat and power. 4 figs

  17. Load balancing in integrated optical wireless networks

    DEFF Research Database (Denmark)

    Yan, Ying; Dittmann, Lars; Wong, S-W.

    2010-01-01

    In this paper, we tackle the load balancing problem in Integrated Optical Wireless Networks, where cell breathing technique is used to solve congestion by changing the coverage area of a fully loaded cell tower. Our objective is to design a load balancing mechanism which works closely...... with the integrated control scheme so as to maximize overall network throughput in the integrated network architecture. To the best of our knowledge no load balancing mechanisms, especially based on the Multi-Point Control Protocol (MPCP) defined in the IEEE 802.3ah, have been proposed so far. The major research...... issues are outlined and a cost function based optimization model is developed for power management. In particularly, two alternative feedback schemes are proposed to report wireless network status. Simulation results show that our proposed load balancing mechanism improves network performances....

  18. The Balance Attack Against Proof-Of-Work Blockchains: The R3 Testbed as an Example

    OpenAIRE

    Natoli, Christopher; Gramoli, Vincent

    2016-01-01

    In this paper, we identify a new form of attack, called the Balance attack, against proof-of-work blockchain systems. The novelty of this attack consists of delaying network communications between multiple subgroups of nodes with balanced mining power. Our theoretical analysis captures the precise tradeoff between the network delay and the mining power of the attacker needed to double spend in Ethereum with high probability. We quantify our probabilistic analysis with statistics taken from th...

  19. Detailed balance of the Feynman micromotor

    Science.gov (United States)

    Abbott, Derek; Davis, Bruce R.; Parrondo, Juan M. R.

    1999-09-01

    One existing implication of micromotors is that they can be powered by rectifying non-equilibrium thermal fluctuations or mechanical vibrations via the so-called Feynman- micromotor. An example of mechanical rectification is found in the batteryless wristwatch. The original concept was described in as early as 1912 by Smoluchowski and was later revisited in 1963 by Feynman, in the context of rectifying thermal fluctuations to obtain useful motion. It has been shown that, although rectification is impossible at equilibrium, it is possible for the Feynman-micromotor to perform work under non-equilibrium conditions. These concepts can now be realized by MEMS technology and may have exciting implications in biomedicine - where the Feynman- micromotor can be used to power a smart pill, for example. Previously, Feynman's analysis of the motor's efficiency has been shown to be flawed by Parrondo and Espanol. We now show there are further problems in Feynman's treatment of detailed balance. In order to design and understand this device correctly, the equations of detailed balance must be found. Feynman's approach was to use probabilities based on energies and we show that this is problematic. In this paper, we demonstrate corrected equations using level crossing probabilities instead. A potential application of the Feynman-micromotor is a batteryless nanopump that consists of a small MEMS chip that adheres to the skin of a patient and dispense nanoliter quantities of medication. Either mechanical or thermal rectification via a Feynman- micromotor, as the power source, is open for possible investigation.

  20. Large-scale integration of wind power into power systems as well as on transmission networks for offshore wind power plants. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Betancourt, Uta; Ackermann, Thomas (eds.)

    2013-11-01

    This proceedings contains contributions to the followings main topics: Grid integration experiences; Flexibility and economics of integration; Voltage control issues; Offshore wind power plants; Forecasting; Grid code issues; HVDC connection issues; Frequency control issues; National grid's perspective; Power system balancing; Power system issues; New grid and generators issues; Flexibility with storage and demand side management; AC connected offshore wind power plants; Economic and market issues; Modelling issues; Offshore grid issues.

  1. 18 CFR 367.4330 - Account 433, Balance transferred from income.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Account 433, Balance transferred from income. 367.4330 Section 367.4330 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE PUBLIC UTILITY HOLDING COMPANY ACT OF 2005, FEDERAL POWER ACT AND NATURAL GAS...

  2. Voltage Scheduling Droop Control for State-of-Charge Balance of Distributed Energy Storage in DC Microgrids

    DEFF Research Database (Denmark)

    Li, Chendan; Dragicevic, Tomislav; Aldana, Nelson Leonardo Diaz

    2014-01-01

    Due to higher power quality, lower conversion loss, and more DC loads, there has been an increasing awareness on DC microgrid. Previous emphasis has been on equal power sharing among different units in the DC microgrid, while overlooking the coordination of the energy storage units to maintain...... the State-of-Charge balance. In this paper, a new droop method based on voltage scheduling for State-of-Charge balance is proposed to keep the SoC balance for the energy storage units. The proposed method has the advantage of avoiding the stability problem existed in traditional methods based on droop gain...... scheduling. Simulation experiment is taken in Matlab on a DC microgrid with two distributed energy storage units. The simulation results show that the proposed method has successfully achieved SoC balance during the load changes while maintaining the DC bus voltage within the allowable range....

  3. The impact of microgeneration upon the Dutch balancing market

    NARCIS (Netherlands)

    Van der Veen, R.A.C.; De Vries, L.J.

    2009-01-01

    The share of microgeneration (power generation at the level of households and small businesses) in the Dutch electricity system continues to grow. Over time, this development may pose a threat to the reliability and efficiency of the Dutch electricity balancing market. We investigated possible

  4. Three-phase Power Flow Calculation of Low Voltage Distribution Network Considering Characteristics of Residents Load

    Science.gov (United States)

    Wang, Yaping; Lin, Shunjiang; Yang, Zhibin

    2017-05-01

    In the traditional three-phase power flow calculation of the low voltage distribution network, the load model is described as constant power. Since this model cannot reflect the characteristics of actual loads, the result of the traditional calculation is always different from the actual situation. In this paper, the load model in which dynamic load represented by air conditioners parallel with static load represented by lighting loads is used to describe characteristics of residents load, and the three-phase power flow calculation model is proposed. The power flow calculation model includes the power balance equations of three-phase (A,B,C), the current balance equations of phase 0, and the torque balancing equations of induction motors in air conditioners. And then an alternating iterative algorithm of induction motor torque balance equations with each node balance equations is proposed to solve the three-phase power flow model. This method is applied to an actual low voltage distribution network of residents load, and by the calculation of three different operating states of air conditioners, the result demonstrates the effectiveness of the proposed model and the algorithm.

  5. Conclusions drawn of tritium balance in light water reactors

    International Nuclear Information System (INIS)

    Dolle, L.; Bazin, J.

    1978-01-01

    In the tritium balance of pressurized water reactors, using boric acid and lithium in the cooling water, contribution of the tritium produced by fission, diffusing through the zircalloy of the fuel cladding estimated to 0.1%, was not in agreement with quantities measured in reactors. It is still difficult to estimate what percentage is represented by the tritium formed by fission in the fuel, owing to diffusion through cladding. The tritium balance in different working nuclear power stations is consequently of interest. The tritium balance method in the water of the cooling circuit of PWR is fast and experimentally simple. It is less sensitive to errors originating from fission yields than balance of tritium produced by fission in the fuel. A tritium balance in the water of the cooling circuit of Biblis-A, with a specific burn-up of 18000 MWd/t gives a better precision. Diffusion rate of tritium produced by fission was less than 0.2%. So low a contribution is a justification to the use of lithium with an isotopic purity of 99.9% of lithium 7 to limit at a low value the residual lithium 6 [fr

  6. Rejuvinasi Sistem Checks and Balances Dalam Sistem Ketatanegaraan di Indonesia

    Directory of Open Access Journals (Sweden)

    Indra Rahmatullah

    2016-04-01

    Full Text Available Rejuvenation of Check and Balance System in Statehood System in Indonesia. Instead of delegated to only a person or an Institution, State Sovereignty shall be divided into some Institutions (separation of power.  The concept of Separation of power is difficult to be implemented because the each State Institution cannot share their power, therefore the concept of distribution of power has been introduced as alternative. This concept recognise Check and balances system. However, It will not guarantee harmony between State Institution. It exist the tension between State Institutions because They feel having the same authority, as seen in some cases such as between Parliament and president on Bill of  head of regional election, Police Department and Commission of Eradication Corruption and the latest is the conflict between Supreme Court and Judicial Commission. DOI: 10.15408/jch.v1i2.2992

  7. Review of Power System Stability with High Wind Power Penetration

    DEFF Research Database (Denmark)

    Hu, Rui; Hu, Weihao; Chen, Zhe

    2015-01-01

    analyzing methods and stability improvement approaches. With increasing wind power penetration, system balancing and the reduced inertia may cause a big threaten for stable operation of power systems. To mitigate or eliminate the wind impacts for high wind penetration systems, although the practical......This paper presents an overview of researches on power system stability with high wind power penetration including analyzing methods and improvement approaches. Power system stability issues can be classified diversely according to different considerations. Each classified issue has special...... and reliable choices currently are the strong outside connections or sufficient reserve capacity constructions, many novel theories and approaches are invented to investigate the stability issues, looking forward to an extra-high penetration or totally renewable resource based power systems. These analyzing...

  8. Power balance equation in electron beam evaporation process

    International Nuclear Information System (INIS)

    Blumenfeld, L.; Soubbaramayer.

    1994-01-01

    The aim of the paper is to solve the equation giving the total power of the gun, used in the electron beam evaporation process, in terms of the power used to generated the vapor stream and the three main power losses due to three parasite phenomena: turbulent thermal convection in the molten pool, electron back scattering and heat radiation from the vapor emitting surface. Scaling laws are first reviewed and results are given with the example of the evaporation of aluminium with a 5 kW axisymmetric gun working in steady state mode. The influence of an applied magnetic field on the evaporation rate is also examined. 5 refs., 3 figs., 1 tab

  9. Integration of large amounts of wind power. Markets for trading imbalances

    Energy Technology Data Exchange (ETDEWEB)

    Neimane, Viktoria; Axelsson, Urban [Vattenfall Research and Development AB, Stockholm (Sweden); Gustafsson, Johan; Gustafsson, Kristian [Vattenfall Nordic Generation Management, Stockholm (Sweden); Murray, Robin [Vattenfall Vindkraft AB, Stockholm (Sweden)

    2008-07-01

    The well-known concerns about wind power are related to its intermittent nature and difficulty to make exact forecasts. The expected increase in balancing and reserve requirements due to wind power has been investigated in several studies. This paper takes the next step in studying integration of large amounts of wind power in Sweden. Several wind power producers' and corresponding balance providers' perspective is taken and their imbalance costs modeled. Larger producers having wind power spread over larger geographical areas will have lower relative costs than producers having their units concentrated within limited geographical area. Possibilities of the wind power producers to reduce the imbalance costs by acting on after sales market are exposed and compared. (orig.)

  10. Periodically Swapping Modulation (PSM) Strategy for Three-Level (TL) DC/DC Converter with Balanced Switch Currents

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Zhang, Qi

    2018-01-01

    The asymmetrical modulation strategy is widely used in various types of three-level (TL) DC/DC converters, while the current imbalance among the power switches is one of the important issues. In this paper, a novel periodically swapping modulation (PSM) strategy is proposed for balancing the power...... switches’ currents in various types of TL DC/DC converters. In the proposed PSM strategy, the driving signals of the switch pairs are swapped periodically, which guarantees that the currents through the power switches are kept balanced in every two switching periods. Therefore, the proposed PSM...... strategy can effectively improve the reliability of the converter by balancing the power losses and thermal stresses among the power switches. The operation principle and performances of the proposed PSM strategy are analyzed in detail. Finally, the simulation and experimental results are presented...

  11. Balancing Power Output and Structural Fatigue of Wave Energy Converters by Means of Control Strategies

    Directory of Open Access Journals (Sweden)

    Francesco Ferri

    2014-04-01

    Full Text Available In order to reduce the cost of electricity produced by wave energy converters (WECs, the benefit of selling electricity as well as the investment costs of the structure has to be considered. This paper presents a methodology for assessing the control strategy for a WEC with respect to both energy output and structural fatigue loads. Different active and passive control strategies are implemented (proportional (P controller, proportional-integral (PI controller, proportional-integral-derivative with memory compensation (PID controller, model predictive control (MPC and maximum energy controller (MEC, and load time-series resulting from numerical simulations are used to design structural parts based on fatigue analysis using rain-flow counting, Stress-Number (SN curves and Miner’s rule. The objective of the methodology is to obtain a cost-effective WEC with a more comprehensive analysis of a WEC based on a combination of well known control strategies and standardised fatigue methods. The presented method is then applied to a particular case study, the Wavestar WEC, for a specific location in the North Sea. Results, which are based on numerical simulations, show the importance of balancing the gained power against structural fatigue. Based on a simple cost model, the PI controller is shown as a viable solution.

  12. THE EAP: A FAILURE OF THE EUROPEAN NEIGHBOURHOOD POLICY OR SHARING A POWER BALANCE IN THE NEIGHBOURHOOD?

    Directory of Open Access Journals (Sweden)

    Nona TATIASHVILI

    2016-10-01

    Full Text Available The present paper analyses achievements and challenges of the EaP in the prism of EU-Russia asymmetric energy interdependence, as the major factor affecting the successful implementation of the Eastern partnership. To identify whether energy interdependence is the main sphere of interest in the EaP neighbourhood, where EU-Russia common interests intersect in one point or is it a sharing a power balance in “common neighbourhood”?. The research paper reviews major policy documents of the ENP/EaP, in order to analyze to what extent is policy coherent/incoherent towards partner countries. Moreover, the paper evaluates the European neighbourhood external policy instruments (the ENP/EaP from the perspective of three prioritised countries of the Eastern partnership: Moldova, Georgia and Ukraine, including the analysis of the effectiveness of proposed incentives under the ENP/EaP, as sufficient instruments for successful implementation of the Eastern partnership, in the presence of unpredictable external veto player.

  13. Interchangeability of the Wii Balance Board for Bipedal Balance Assessment.

    Science.gov (United States)

    Bonnechère, Bruno; Jansen, Bart; Omelina, Lubos; Rooze, Marcel; Van Sint Jan, Serge

    2015-08-27

    Since 2010, an increasing interest in more portable and flexible hardware for balance and posture assessment led to previously published studies determining whether or not the Wii Balance Board could be used to assess balance and posture, both scientifically and clinically. However, no previous studies aimed at comparing results from different Wii Balance Boards for clinical balance evaluation exist. The objective of this crossover study is to assess the interchangeability of the Wii Balance Board. A total of 6 subjects participated in the study and their balance was assessed using 4 different Wii Balance Boards. Trials were recorded simultaneously with Wii Balance Boards and with a laboratory force plate. Nine relevant clinical parameters were derived from center of pressure displacement data obtained from Wii Balance Board and force plate systems. Intraclass correlation coefficients (ICC), F tests, and Friedman tests were computed to assess the agreement between trials and to compare the Wii Balance Board and force plate results. Excellent correlations were found between the Wii Balance Board and force plate (mean ρ =.83). With the exception of 2 parameters, strong to excellent agreements were found for the 7 remaining parameters (ICC=.96). No significant differences were found between trials recorded with different Wii Balance Boards. Our results indicate that for most of the parameters analyzed, balance and posture assessed with one Wii Balance Board were statistically similar to results obtained from another. Furthermore, the good correlation between the Wii Balance Board and force plate results shows that Wii Balance Boards can be reliably used for scientific assessment using most of the parameters analyzed in this study. These results also suggest that the Wii Balance Board could be used in multicenter studies and therefore, would allow for the creation of larger populations for clinical studies. Ethical Committee of the Erasme Hospital (CCB B406201215142

  14. Market Integration of Virtual Power Plants

    DEFF Research Database (Denmark)

    Petersen, Mette Kirschmeyer

    increasingly challenging due to the intrinsic variability of production technologies such as photovoltaics and wind turbines. In a Smart Grid system the balancing task will therefore be handled by mobilizing flexibility on the consumption side. This Thesis assumes that the Smart Grid should be commercially......Global efforts to reduce emissions of carbon dioxide drives the introduction of renewable power production technologies into the existing power system. The real-time balance between production and consumption must, however, still be maintained at all times. Unfortunately, this is becoming....... It does however significantly sharpen the discussion of the flexibility concept and provides a categorization of flexible systems. This Thesis also investigates what value can be created from the different types of flexibility by assuming that the Virtual Power Plant will generate profit by trading...

  15. Multi-Objective Reservoir Optimization Balancing Energy Generation and Firm Power

    Directory of Open Access Journals (Sweden)

    Fang-Fang Li

    2015-07-01

    Full Text Available To maximize annual power generation and to improve firm power are important but competing goals for hydropower stations. The firm power output is decisive for the installed capacity in design, and represents the reliability of the power generation when the power plant is put into operation. To improve the firm power, the whole generation process needs to be as stable as possible, while the maximization of power generation requires a rapid rise of the water level at the beginning of the storage period. Taking the minimal power output as the firm power, both the total amount and the reliability of the hydropower generation are considered simultaneously in this study. A multi-objective model to improve the comprehensive benefits of hydropower stations are established, which is optimized by Non-dominated Sorting Genetic Algorithm-II (NSGA-II. The Three Gorges Cascade Hydropower System (TGCHS is taken as the study case, and the Pareto Fronts in different search spaces are obtained. The results not only prove the effectiveness of the proposed method, but also provide operational references for the TGCHS, indicating that there is room of improvement for both the annual power generation and the firm power.

  16. On the diversity enhancement and power balancing of per-subcarrier transmit antenna selection in OFDM systems

    KAUST Repository

    Park, Kihong

    2011-01-01

    In this paper, we consider multicarrier systems with multiple transmit antennas under a power-balancing constraint. Applying transmit antenna selection and discrete rate-adaptive modulation using M-ary quadrature-amplitude modulation (QAM) according to the channel variation per subcarrier, we develop an optimal transmit antenna selection scheme in terms of the maximum spectral efficiency, where all the possible groupings for sending the same information-bearing signals in a group of subcarriers are searched, and the groups of subcarriers for providing the frequency diversity gain are formed. In addition, we propose a suboptimal method for reducing the computational complexity of the optimal method. The suboptimal scheme considers only the subcarriers under outage, and these subcarriers are sequentially combined until the required signal-to-noise ratio (SNR) is met. Numerical results show that the proposed suboptimal method with diversity combining outperforms the optimal antenna selection without diversity combining, as introduced in the work of Sandell and Coon, particularly for low-SNR regions, and offers the spectral efficiency close to the optimal method with diversity combining while maintaining lower complexity. © 2011 IEEE.

  17. Development of balanced downflow type surface condensers, (2)

    International Nuclear Information System (INIS)

    Tomida, Akira; Oshima, Yoshikuni; Okochi, Isao; Izumi, Kenkichi.

    1976-01-01

    As the size of the condensers for power generation plants grew large, the new balanced downflow type condenser was developed and completed on the basis of the experiment on steam flow according to the two-dimensional flow model, the analysis of the performance in a tube nest with a computer, and the studies on the effect of outside liquid film and the reheating deaeration of condensate. When the balanced downflow type condensers were adopted for actual plants, the construction, strength and production method were examined, and the reliability of the new condenser was confirmed by the thermal characteristic experiment with the model similar to the actual machine. The condenser comprises a condenser body, supporting plates, cooling tubes, tube plates, water chambers, and reinforcements, and the cooling tubes are arranged so as to exchange heat effectively. The arrangement of tubes is divided into three regions, namely radiation portion, densely arranged portion, and air cooling portion. In the balanced downflow type condensers, the dilution by utilizing condensate is provided against ammonia attack. The apparatuses for the thermal characteristic experiment and the experimental results, and the results of the performance test on the actual balanced downflow type condenser are reported. (Kako, I.)

  18. Work-Life Balance Practices in Nigeria: A Comparison of Three Sectors

    OpenAIRE

    Ojo Ibiyinka Stella; Salau Odunayo Paul; Falola Hezekiah Olubusayo

    2014-01-01

    The study investigates the concept of work-life balance (WLB) policies and practices in three sectors of the Nigerian Economy namely the Banking, Educational and Power Sector. The types of WLB initiatives available in the three sectors were explored and the barriers to implementation of the WLB initiatives were identified. This research implored quantitative methods to investigate the work-life balance practices in three sectors of the Nigerian Economy. This was achieved using an in-depth cas...

  19. Wind power, distrubted generation and transmission

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    the possibilities for integration of even more wind power using new power balancing strategies that exploit the possibilities given by the existence of CHP plants as well as the impact of heat pumps for district heating. The analyses demonstrate that it is possible to accommodate 50% or more wind power without......Denmark has the World?s highest penetration of wind power in electricity generation with a share of 15.0% of total domestic demand in 2002 (DEA, 2004). This is unevenly distributed in the two electricity systems of Denmark giving a share as high as 20.7% in Western Denmark in 2003 up from 18...... power balancing strategies are not applied, costly grid expansions will follow expansions in installed wind power capacity....

  20. Battery voltage-balancing applications of disk-type radial mode Pb(Zr • Ti)O3 ceramic resonator

    Science.gov (United States)

    Thenathayalan, Daniel; Lee, Chun-gu; Park, Joung-hu

    2017-10-01

    In this paper, we propose a novel technique to build a charge-balancing circuit for series-connected battery strings using various kinds of disk-type ceramic Pb(Zr • Ti)O3 piezoelectric resonators (PRs). The use of PRs replaces the whole external battery voltage-balancer circuit, which consists mainly of a bulky magnetic element. The proposed technique is validated using different ceramic PRs and the results are analyzed in terms of their physical properties. A series-connected battery string with a voltage rating of 61.5 V is set as a hardware prototype under test, then the power transfer efficiency of the system is measured at different imbalance voltages. The performance of the proposed battery voltage-balancer circuit employed with a PR is also validated through hardware implementation. Furthermore, the temperature distribution image of the PR is obtained to compare power transfer efficiency and thermal stress under different operating conditions. The test results show that the battery voltage-balancer circuit can be successfully implemented using PRs with the maximum power conversion efficiency of over 96% for energy storage systems.

  1. Biomechanical assessment of dynamic balance: Specificity of different balance tests.

    Science.gov (United States)

    Ringhof, Steffen; Stein, Thorsten

    2018-04-01

    Dynamic balance is vitally important for most sports and activities of daily living, so the assessment of dynamic stability has become an important issue. In consequence, a large number of balance tests have been developed. However, it is not yet known whether these tests (i) measure the same construct and (ii) can differentiate between athletes with different balance expertise. We therefore studied three common dynamic balance tests: one-leg jump landings, Posturomed perturbations and simulated forward falls. Participants were 24 healthy young females in regular training in either gymnastics (n = 12) or swimming (n = 12). In each of the tests, the participants were instructed to recover balance as quickly as possible. Dynamic stability was computed by time to stabilization and margin of stability, deduced from force plates and motion capture respectively. Pearson's correlations between the dynamic balance tests found no significant associations between the respective dynamic stability measures. Furthermore, independent t-tests indicated that only jump landings could properly distinguish between both groups of athletes. In essence, the different dynamic balance tests applied did not measure the same construct but rather task-specific skills, each of which depends on multifactorial internal and external constraints. Our study therefore contradicts the traditional view of considering balance as a general ability, and reinforces that dynamic balance measures are not interchangeable. This highlights the importance of selecting appropriate balance tests. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Effects of dynamic posturographic balance training versus conventional balance training on mobility and balance in elderly

    International Nuclear Information System (INIS)

    Saddiqi, F.A.; Masood, T.

    2017-01-01

    To determine the effects of dynamic posturographic balance training versus conventional balance training in improving mobility and balance in elderly. Methodology: Forty subjects between 50 to 80 years of age were selected via non-probability convenience sampling technique, for this randomized controlled trial. Both females and males with no major co-morbid conditions and cognitive impairments were recruited and randomized via coin toss method into two equal groups: Dynamic Posturographic balance training (DPG) group and Conventional balance training (CBT) group. The DPG training was provided via Biodex Balance System (Static and Dynamic). Both groups received interventions 3 times (35 to 45min each day) a week for 8 weeks, after which terminal assessment was done. Data were collected on demographic profile, balance via berg balance score and mobility by using Timed Up and Go Test. Independent samples t test was used to check difference between CBT group and DPG Group and repeated measures Analysis of Variance (ANOVA) was used for within-group analysis. Results: Baseline analysis of Berg balance scale and timed up and go test between two groups showed no significant difference with (p 0.805 and 0.251, respectively). After 8 weeks of intervention, there was significant difference between the groups in both variables (p 0.019 and 0.001, respectively). Conclusion: Dynamic posturographic balance training was more effective in improving dynamic balance and mobility in elderly population in comparison to conventional balance training. (author)

  3. Low cost balancing unit design

    Science.gov (United States)

    Golembiovsky, Matej; Dedek, Jan; Slanina, Zdenek

    2017-06-01

    This article deals with the design of a low-cost balancing system which consist of battery balancing units, accumulator pack units and coordinator unit with interface for higher level of battery management system. This solution allows decentralized mode of operation and the aim of this work is implementation of controlling and diagnostic mechanism into an electric scooter project realized at Technical university of Ostrava. In todays world which now fully enjoys the prime of electromobility, off-grid battery systems and other, it is important to seek the optimal balance between functionality and the economy side of BMS that being electronics which deals with secondary cells of batery packs. There were numerous sophisticated, but not too practical BMS models in the past, such as centralized system or standalone balance modules of individual cells. This article aims at development of standalone balance modules which are able to communicate with the coordinator, adjust their parameters and ensure their cells safety in case of a communication failure. With the current worldwide cutting cost trend in mind, the emphasis was put on the lowest price possible for individual component. The article is divided into two major categories, the first one being desing of power electronics with emphasis on quality, safety (cooling) and also cost. The second part describes development of a communication interface with reliability and cost in mind. The article contains numerous graphs from practical measurements. The outcome of the work and its possible future is defined in the conclusion.

  4. The relevance of clinical balance assessment tools to differentiate balance deficits

    OpenAIRE

    Mancini, Martina; Horak, Fay B

    2010-01-01

    Control of balance is complex and involves maintaining postures, facilitating movement, and recovering equilibrium. Balance control consists of controlling the body center of mass over its limits of stability. Clinical balance assessment can help assess fall risk and/or determine the underlying reasons for balance disorders. Most functional balance assessment scales assess fall risk and the need for balance rehabilitation but do not differentiate types of balance deficits. A system approach t...

  5. Development of a Common Nordic Balance Settlement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-02-15

    NordREG finds it essential for the customers that a common integrated end-user electricity market is developed and that all end-users are able to take part in the Nordic market. A common Nordic balance settlement is one important part of such a change. However, attention has to be paid to the comments that a badly designed common system is worse than well-designed national systems. It is thus important that the change to a common balance settlement is so thoroughly investigated that the common system gives a basis for a well-functioning market. An important basis for such a change is an agreed vision for the process: The present different systems for balance settlement shall by the year 2010 be replaced by a common Nordic balance settlement. This means that: It will be possible for a supplier to sell to the whole Nordic market from one legal entity and using only one system for customer management and reporting. The common Nordic balance settlement will be designed in such a way that it contributes to a well functioning market. This means for example that it will be attractive even for small suppliers and some end-users to be balance responsible parties. It is feasible that the first phase is focused on those present differences that are most decisive for fulfilment of the vision. NordREG recommends that the following issues shall be discussed and agreed in co-operation between NordREG, Nordel and relevant stakeholders in the first phase: The definition shall include how the common Nordic balance settlement shall interact with the balance control and the balance regulation of the interconnected power system and the balance settlement between countries performed by the TSOs. The definition should include the cost-base for common Nordic balance settlement in relation to other system responsibility costs. The core activities of system responsibility have also been analyzed by NordREG. It is important to find a balance between inter alia the need for simplicity and the

  6. Development of a Common Nordic Balance Settlement

    International Nuclear Information System (INIS)

    2006-02-01

    NordREG finds it essential for the customers that a common integrated end-user electricity market is developed and that all end-users are able to take part in the Nordic market. A common Nordic balance settlement is one important part of such a change. However, attention has to be paid to the comments that a badly designed common system is worse than well-designed national systems. It is thus important that the change to a common balance settlement is so thoroughly investigated that the common system gives a basis for a well-functioning market. An important basis for such a change is an agreed vision for the process: The present different systems for balance settlement shall by the year 2010 be replaced by a common Nordic balance settlement. This means that: It will be possible for a supplier to sell to the whole Nordic market from one legal entity and using only one system for customer management and reporting. The common Nordic balance settlement will be designed in such a way that it contributes to a well functioning market. This means for example that it will be attractive even for small suppliers and some end-users to be balance responsible parties. It is feasible that the first phase is focused on those present differences that are most decisive for fulfilment of the vision. NordREG recommends that the following issues shall be discussed and agreed in co-operation between NordREG, Nordel and relevant stakeholders in the first phase: The definition shall include how the common Nordic balance settlement shall interact with the balance control and the balance regulation of the interconnected power system and the balance settlement between countries performed by the TSOs. The definition should include the cost-base for common Nordic balance settlement in relation to other system responsibility costs. The core activities of system responsibility have also been analyzed by NordREG. It is important to find a balance between inter alia the need for simplicity and the

  7. Higher balance task demands are associated with an increase in individual alpha peak frequency

    Directory of Open Access Journals (Sweden)

    Thorben eHülsdünker

    2016-01-01

    Full Text Available Balance control is fundamental for most daily motor activities, and its impairment is associated with an increased risk of falling. Growing evidence suggests the human cortex is essentially contributing to the control of standing balance. However, the exact mechanisms remain unclear and need further investigation. In a previous study we introduced a new protocol to identify electrocortical activity associated with performance of different continuous balance tasks with the eyes opened. The aim of this study was to extend our previous results by investigating the individual alpha peak frequency (iAPF, a neurophysiological marker of thalamo-cortical information transmission, which remained unconsidered so far in balance research. Thirty-seven subjects completed nine balance tasks varying in surface stability and base of support. Electroencephalography (EEG was recorded from 32 scalp locations throughout balancing with the eyes closed to ensure reliable identification of the iAPF. Balance performance was quantified as the sum of anterior-posterior and medio-lateral movements of the supporting platform. The iAPF, as well as power in the theta, lower alpha and upper alpha frequency bands were determined for each balance task after applying an ICA-based artifact rejection procedure. Higher demands on balance control were associated with a global increase in iAPF and a decrease in lower alpha power. These results may indicate increased thalamo-cortical information transfer and general cortical activation, respectively. In addition, a significant increase in upper alpha activity was observed in the fronto-central region whereas it decreased in the centro-parietal region. Furthermore, midline theta increased with higher task demands probably indicating activation of error detection/processing mechanisms. IAPF as well as theta and alpha power were correlated with platform movements. The results provide new insights into spectral and spatial characteristics

  8. Does photovoltaics reduce the environmental intensity of Swiss electrical power?

    International Nuclear Information System (INIS)

    Stucki, M.; Frischknecht, R.

    2010-01-01

    This article presents and discusses knowledge gained from current eco-balances made concerning electricity from solar cells. The use of photovoltaic systems in Switzerland, especially in the light of climate warming, as well as discussions on appropriate locations for the disposal of nuclear wastes are examined. The authors are of the opinion that current eco-balances can provide an objective basis for the development of qualified answers to such questions. The eco-balances for electricity generated by solar cells is discussed in detail. The development of photovoltaic technologies since 1992 is examined and scenarios for the period up to 2050 are discussed. Comparisons are made concerning solar power in Switzerland and Europe and the advantages of using solar power in Switzerland as a replacement for power from non-renewable resources in Europe are discussed

  9. Power System Operation with Large Scale Wind Power Integration

    DEFF Research Database (Denmark)

    Suwannarat, A.; Bak-Jensen, B.; Chen, Z.

    2007-01-01

    to the uncertain nature of wind power. In this paper, proposed models of generations and control system are presented which analyze the deviation of power exchange at the western Danish-German border, taking into account the fluctuating nature of wind power. The performance of the secondary control of the thermal......The Danish power system starts to face problems of integrating thousands megawatts of wind power, which produce in a stochastic behavior due to natural wind fluctuations. With wind power capacities increasing, the Danish Transmission System Operator (TSO) is faced with new challenges related...... power plants and the spinning reserves control from the Combined Heat and Power (CHP) units to achieve active power balance with the increased wind power penetration is presented....

  10. Japanese energy balances after the Great East Japan Earthquake

    International Nuclear Information System (INIS)

    Tsuzuki, Kazuhiro; Moriyama, Ryo; Ishimoto, Yuki; Tomikatsu, Koji; Hagiwara, Naoto

    2012-01-01

    After the Great East Japan Earthquake, disaster response and risk of nuclear accident became a new issue and the public against nuclear power was increasing with knowing a long-term period required for restoration from Fukushima accident. This article described effects of 'de-nuclear power' policy with no additional plants on energy balances in 2030 and 2050 with simulated energy model based on government's long-term energy supply-demand outlook issued in 2009. Main assumed conditions were as follows; (1) nuclear power of case B) 40 years operation and C) 60 years operation, (2) share of photovoltaic and wind power was assumed to be 9% of total power generation and the same as planned before the earthquake disaster, which could not replace nuclear power and (3) final consumption of case 2) 8% saving and 3) 20% saving. Effects of 'de-nuclear power' in 2030 were (1) CO 2 emission difference between B) and C) was 50 Mt and (2) estimated cost increase between B) and C) was 0.1 T yen/year for CO 2 emission, 1 T yen/year for LNG procurement and 2.4 T yen for thermal power construction. Energy balances in 2050 were much influenced by trend of renewable energy technology development and fossil energy procurement and use. Sophisticated power change measures using storage battery for renewable energy should be developed, otherwise if power change were dealt with thermal power, share would be limited to 15-20% of total power generation. If CO 2 emission in 2050 was limited to 50% instead of formally announced 80% of CO 2 emission in 1990, share of non-fossil power (nuclear power + renewable energy) became almost 100% for case 3). Base technology of nuclear power should remain as option for the case where fossil energy procurement and CO 2 emission limit became restrictive in 2050. (T. Tanaka)

  11. Life cycle analysis of advanced nuclear power generation technologies

    International Nuclear Information System (INIS)

    Uchiyama, Yoji; Yokoyama, Hayaichi

    1996-01-01

    In this research, as for light water reactors and fast breeder reactors, for the object of all the processes from the mining, transport and refining of fuel, electric power generation to the treatment and disposal of waste, the amount of energy input and the quantity of CO 2 emission over the life cycle were analyzed, and regarding the influence that the technical progress of nuclear power generation exerted to environment, the effect of improvement was elucidated. Attention has been paid to nuclear power generation as its CO 2 emission is least, and the effect of global warming is smallest. In order to reduce the quantity of radioactive waste generation in LWRs and the cost of fuel cycle, and to extend the operation cycle, the technical development for heightening fuel burnup is in progress. The process of investigation of the new technologies of nuclear power generation taken up in this research is described. The analysis of the energy balance of various power generation methods is discussed. In the case of pluthermal process, the improvement of energy balance ratio is dependent on uranium enrichment technology. Nuclear power generation requires much materials and energy for the construction, and emits CO 2 indirectly. The CO 2 unit emission based on the analysis of energy balance was determined for the new technologies of nuclear power generation, and the results are shown. (K.I.)

  12. Software for optimal selection of places for installation of balancing devices in 0,4 kV electric power systems loaded with electric motors

    Directory of Open Access Journals (Sweden)

    Romanova Victoria

    2017-01-01

    Full Text Available This publication considers the issues of development of the software program for designing of 0,4 kV power supply systems with motor-actuated load under voltage unsymmetry conditions (using the example of the Trans-Baikal Territory. Voltage unsymmetry is practically constant phenomenon in the electric power networks of different voltage types. Voltage unsymmetry effects significantly the electric power consumers, including the supply mains itself. It has especially negative impact on the electrical equipment operation process and its lifetime. The urgency of the problem is confirmed by multiple research on the same topic and by significant number of damages suffered by the electric power consumers staying in service (especially in the Trans-Baikal Territory and in the Far-East regions. Voltage unsymmetry causes economic loss and reduction of the electromagnetic interference value by the voltage unsymmetry coefficient in negative-phase sequence (K2U gives inevitable economic effect accordingly. However, the payback period for the activities aimed at reduction of electromagnetic interference, will vary from some months to several years. The more accurate value of the payback period may be obtained using the developed software program. The developed software design program is implemented by means of the programming language C# in Microsoft Visual Studio environment, using the built-in cross-platform database SQLite. The software program shall allow making quick and accurate calculation of the power losses, to determine the economic feasibility of provision special measures for removal of the voltage unsymmetry, for determination of optimal application and location of the balancing devices. The software implementation in power systems loaded with electric motors will improve reliability and efficiency of asynchronous motors. The software is of interest for developers of projects on power supply systems for regions with non-linear loads.

  13. Energy Storage for Power Systems Applications: A Regional Assessment for the Northwest Power Pool (NWPP)

    Energy Technology Data Exchange (ETDEWEB)

    Kintner-Meyer, Michael CW; Balducci, Patrick J.; Jin, Chunlian; Nguyen, Tony B.; Elizondo, Marcelo A.; Viswanathan, Vilayanur V.; Guo, Xinxin; Tuffner, Francis K.

    2010-04-01

    Wind production, which has expanded rapidly in recent years, could be an important element in the future efficient management of the electric power system; however, wind energy generation is uncontrollable and intermittent in nature. Thus, while wind power represents a significant opportunity to the Bonneville Power Administration (BPA), integrating high levels of wind resources into the power system will bring great challenges to generation scheduling and in the provision of ancillary services. This report addresses several key questions in the broader discussion on the integration of renewable energy resources in the Pacific Northwest power grid. More specifically, it addresses the following questions: a) how much total reserve or balancing requirements are necessary to accommodate the simulated expansion of intermittent renewable energy resources during the 2019 time horizon, and b) what are the most cost effective technological solutions for meeting load balancing requirements in the Northwest Power Pool (NWPP).

  14. Virtual Reality-Based Center of Mass-Assisted Personalized Balance Training System

    Directory of Open Access Journals (Sweden)

    Deepesh Kumar

    2018-01-01

    Full Text Available Poststroke hemiplegic patients often show altered weight distribution with balance disorders, increasing their risk of fall. Conventional balance training, though powerful, suffers from scarcity of trained therapists, frequent visits to clinics to get therapy, one-on-one therapy sessions, and monotony of repetitive exercise tasks. Thus, technology-assisted balance rehabilitation can be an alternative solution. Here, we chose virtual reality as a technology-based platform to develop motivating balance tasks. This platform was augmented with off-the-shelf available sensors such as Nintendo Wii balance board and Kinect to estimate one’s center of mass (CoM. The virtual reality-based CoM-assisted balance tasks (Virtual CoMBaT was designed to be adaptive to one’s individualized weight-shifting capability quantified through CoM displacement. Participants were asked to interact with Virtual CoMBaT that offered tasks of varying challenge levels while adhering to ankle strategy for weight shifting. To facilitate the patients to use ankle strategy during weight-shifting, we designed a heel lift detection module. A usability study was carried out with 12 hemiplegic patients. Results indicate the potential of our system to contribute to improving one’s overall performance in balance-related tasks belonging to different difficulty levels.

  15. Estimated status of the power supply and demand balance in France

    International Nuclear Information System (INIS)

    2005-01-01

    The aim of the estimated status made by the energy transportation network (RTE) is to quantify the additional power generation means to put into service in the forthcoming years according to 3 reference scenarios of power consumption. These scenarios take into consideration different factors like: the growth of consumption, the energy conservation, the development of renewable energy sources, the building of the EPR reactor, the implementation of new fossil-fuel power plants, the decommissioning of old coal-fired power plants etc.. In all cases, the power generation means to be developed must be both peak-type means (combustion turbines for instance) and semi-base means (gas combined cycles for instance). These estimated needs are based on a system failure risk of 3 hours/year as an average. Finally, this status stresses on the need for specific reinforcement means of the supply security in the Provence-Alpes-Cote d'Azur (PACA) and Bretagne (Brittany) regions and also in island systems. (J.S.)

  16. Workload Balancing on Heterogeneous Systems: A Case Study of Sparse Grid Interpolation

    KAUST Repository

    Muraraşu, Alin

    2012-01-01

    Multi-core parallelism and accelerators are becoming common features of today’s computer systems, as they allow for computational power without sacrificing energy efficiency. Due to heterogeneity, tuning for each type of compute unit and adequate load balancing is essential. This paper proposes static and dynamic solutions for load balancing in the context of an application for visualizing high-dimensional simulation data. The application relies on the sparse grid technique for data compression. Its performance critical part is the interpolation routine used for decompression. Results show that our load balancing scheme allows for an efficient acceleration of interpolation on heterogeneous systems containing multi-core CPUs and GPUs.

  17. Dynamic model of frequency control in Danish power system with large scale integration of wind power

    DEFF Research Database (Denmark)

    Basit, Abdul; Hansen, Anca Daniela; Sørensen, Poul Ejnar

    2013-01-01

    This work evaluates the impact of large scale integration of wind power in future power systems when 50% of load demand can be met from wind power. The focus is on active power balance control, where the main source of power imbalance is an inaccurate wind speed forecast. In this study, a Danish...... power system model with large scale of wind power is developed and a case study for an inaccurate wind power forecast is investigated. The goal of this work is to develop an adequate power system model that depicts relevant dynamic features of the power plants and compensates for load generation...... imbalances, caused by inaccurate wind speed forecast, by an appropriate control of the active power production from power plants....

  18. Annual Energy Balance Sheets 2003-2004

    International Nuclear Information System (INIS)

    2005-01-01

    During the year 2004 the supply of primary energy reached 657.6 TWh. That is an increased supply by 16 TWh compared with 2003, The electricity production in hydropower and wind power stations increased by 7 TWh, to 61 TWh during the year 2004. The electricity generated in nuclear power plants was 77.5 TWh, an increase by 10 TWh. During the year 2004 Sweden net exported 2.1 TWh electricity. But in year 2003 we net imported 12.8 TWh electricity. The energy use increased from 406 TWh to 409 TWh between year 2003 and year 2004. The use of coal and coke in manufacturing increased by 22 per cent, and the use of oil products in transport sector increased by 4 per cent. The energy balance sheets are based on data primary recorded in the balance sheets of energy sources, here expressed in a common energy unit, TJ. The production of derived energy is here recorded in a second flow-step comprising energy turnover in energy conversion and is also specified in complementary input-output tables for energy conversion industries

  19. Energy management based on AM/FM/GIS for phase balancing application on distribution systems

    International Nuclear Information System (INIS)

    Kuo, C.-C.; Chao, Y.-T.

    2010-01-01

    Unbalanced feeder systems may deteriorate of power quality, and increase investment and operating costs for distribution systems. The phase swapping method recommends re-phasing circuits of laterals and transformers for making the current and voltage balanced and also reducing feeder loss and voltage drop. In this paper, an application program, based on the automated mapping/facilities management/ geographic information system (AM/FM/GIS) is developed which contains a function of automatically computing Z-bus, load flow and phase balancing of feeders with phase swapping by using easily selecting of feeder on a graphic user interface application. Therefore, the relative data need not be keyed in manually. The presented phase balancing algorithm are based on database and related data structures developed on the AM/FM/GIS and Visual Basic software, which can be integrated into the Tai-Power distribution automation system. Then, the phase balancing algorithm is designed to handle the load patterns and the load of transformers that connect specific feeders when evaluating phase swaps that will result in reduced daily circuit losses over all load points. The proposed application not only can effectively reduce the circuit loss and improves phase balancing, but also enhances power quality efficiently under easily using environment.

  20. Hydro-power

    International Nuclear Information System (INIS)

    Piro, P.

    2010-01-01

    On average the hydro-power sector produces 12% of the electrical power in France. A quarter of this production might pass to another operator than EDF because the end of some grants is nearing (2012 for 12 installations). In France the power of rivers belongs to the state that gives operators grants to harness it. The allowance lasts 75 years usually but for installations below 4.5 MW a permanent and definitive grant is allowed. Most installations are ancient and their investment have been paid off since a long, so hydro-power is the most profitable renewable energy in France. A lot of bidders are expected. Each bid will be assessed on 3 criteria: -) the global energy efficiency of the waterfall, -) a balanced management of the water resource, and -) an economic and financial offer to the state. The balance between the different uses of water is getting more delicate to reach and this renewal of grants will be an opportunity for the state to impose a better preservation of the environment. In July 2008, the French government announced a program for the re launching of the hydro-power, this program has been reduced and now only 3000 GWh supplementary are expected by 2020. (A.C.)

  1. Playing with Powers

    Science.gov (United States)

    Sriraman, Bharath; Strzelecki, Pawel

    2004-01-01

    This paper explores the wide range of pure mathematics that becomes accessible through the use of problems involving powers. In particular we stress the need to balance an applied and context based pedagogical and curricular approach to mathematics with the powerful pure mathematics beneath the simplicity of easily stated and understandable…

  2. The effects of forecast errors on the merchandising of wind power; Auswirkungen von Prognosefehlern auf die Vermarktung von Windstrom

    Energy Technology Data Exchange (ETDEWEB)

    Roon, Serafin von

    2012-02-28

    A permanent balance between consumption and generation is essential for a stable supply of electricity. In order to ensure this balance, all relevant load data have to be announced for the following day. Consequently, a day-ahead forecast of the wind power generation is required, which also forms the basis for the sale of the wind power at the wholesale market. The main subject of the study is the short-term power supply, which compensates errors in wind power forecasting for balancing the wind power forecast errors at short notice. These forecast errors effects the revenues and the expenses by selling and buying power in the day-ahead, intraday and balance energy market. These price effects resulting from the forecast errors are derived from an empirical analysis. In a scenario for the year 2020 the potential of conventional power plants to supply power at short notice is evaluated from a technical and economic point of view by a time series analysis and a unit commitment simulation.

  3. Pulse*Star Inertial Confinement Fusion Reactor: heat transfer loop and balance of plant considerations

    International Nuclear Information System (INIS)

    McDowell, M.W.; Murray, K.A.

    1984-01-01

    A conceptual heat transfer loop and balance of plant design for the Pulse*Star Inertial Confinement Fusion Reactor has been investigated and results are presented. The Pulse*Star reaction vessel, a perforated steel bell jar approximately 11 m in diameter, is immersed in Li 17 Pb 83 coolant which flows through the perforations and forms a 1.5 m thick plenum of droplets around an 8 m diameter inner chamber. The reactor and associated pumps, piping, and steam generators are contained within a 17 m diameter pool of Li 17 Pb 83 coolant to minimize structural requirements and occupied space, resulting in reduced cost. Four parallel heat transfer loops with flow rates of 5.5 m 3 /s each are necessary to transfer 3300 MWt of power. The steam generator design was optimized by finding the most cost-effective combination of heat exchanger area and pumping power. Power balance calculations based on an improved electrical conversion efficiency revealed a net electrical output of 1260 MWe to the bus bar and a resulting net efficiency of 39%. Suggested balance-of-plant layouts are also presented

  4. National energetic balance. Statistical compilation 1985-1991

    International Nuclear Information System (INIS)

    1992-01-01

    Compiles the statistical information supplied by governmental and private institutions which integrate the national energetic sector in Paraguay. The first part, refers to the whole effort of energy; second, energy transformation centres and the last part presents the energy flows, consolidated balances and other economic-power indicators

  5. Interchangeability of the Wii Balance Board for Bipedal Balance Assessment

    OpenAIRE

    Bonnech?re, Bruno; Jansen, Bart; Omelina, Lubos; Rooze, Marcel; Van Sint Jan, Serge

    2015-01-01

    Background Since 2010, an increasing interest in more portable and flexible hardware for balance and posture assessment led to previously published studies determining whether or not the Wii Balance Board could be used to assess balance and posture, both scientifically and clinically. However, no previous studies aimed at comparing results from different Wii Balance Boards for clinical balance evaluation exist. Objective The objective of this crossover study is to assess the interchangeabilit...

  6. BALANCE

    Science.gov (United States)

    Carmichael, H.

    1953-01-01

    A torsional-type analytical balance designed to arrive at its equilibrium point more quickly than previous balances is described. In order to prevent external heat sources creating air currents inside the balance casing that would reiard the attainment of equilibrium conditions, a relatively thick casing shaped as an inverted U is placed over the load support arms and the balance beam. This casing is of a metal of good thernnal conductivity characteristics, such as copper or aluminum, in order that heat applied to one portion of the balance is quickly conducted to all other sensitive areas, thus effectively preventing the fornnation of air currents caused by unequal heating of the balance.

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

    Science.gov (United States)

    Dai, Zhong; Wu, Zhou

    2018-01-01

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

  8. State-of-Charge Balancing Control of a Modular Multilevel Converter with an Integrated Battery Energy Storage

    Directory of Open Access Journals (Sweden)

    Hui Liang

    2018-04-01

    Full Text Available With the fast development of the electric vehicle industry, the reuse of second-life batteries in vehicles are becoming more attractive, however, both the state-of-charge (SOC inconsistency and the capacity inconsistency of second-life batteries have limits in their utilization. This paper focuses on the second-life batteries applied battery energy storage system (BESS based on modular multilevel converter (MMC. By analyzing the power flow characteristics among all sources within the MMC-BESS, a three-level SOC equilibrium control strategy aiming to battery capacity inconsistency is proposed to balance the energy of batteries, which includes SOC balance among three-phase legs, SOC balance between the upper and lower arms of each phase, and SOC balance of submodules within each arm. In battery charging and discharging control, by introducing power regulations based on battery capacity proportion of three-phase legs, capacity deviation between the upper and lower’s arm, and the capacity coefficient of the submodule into the SOC feedback control loop, SOC balance of all battery modules is accomplished, thus effectively improving the energy utilization of second-life battery energy storage system. Finally, the effectiveness and feasibility of the proposed methods are verified by results obtained from simulations and the experimental platform.

  9. Effects of Resisted Sprint Training and Traditional Power Training on Sprint, Jump, and Balance Performance in Healthy Young Adults: A Randomized Controlled Trial.

    Science.gov (United States)

    Prieske, Olaf; Krüger, Tom; Aehle, Markus; Bauer, Erik; Granacher, Urs

    2018-01-01

    Power training programs have proved to be effective in improving components of physical fitness such as speed. According to the concept of training specificity, it was postulated that exercises must attempt to closely mimic the demands of the respective activity. When transferring this idea to speed development, the purpose of the present study was to examine the effects of resisted sprint (RST) vs. traditional power training (TPT) on physical fitness in healthy young adults. Thirty-five healthy, physically active adults were randomly assigned to a RST ( n = 10, 23 ± 3 years), a TPT ( n = 9, 23 ± 3 years), or a passive control group ( n = 16, 23 ± 2 years). RST and TPT exercised for 6 weeks with three training sessions/week each lasting 45-60 min. RST comprised frontal and lateral sprint exercises using an expander system with increasing levels of resistance that was attached to a treadmill (h/p/cosmos). TPT included ballistic strength training at 40% of the one-repetition-maximum for the lower limbs (e.g., leg press, knee extensions). Before and after training, sprint (20-m sprint), change-of-direction speed (T-agility test), jump (drop, countermovement jump), and balance performances (Y balance test) were assessed. ANCOVA statistics revealed large main effects of group for 20-m sprint velocity and ground contact time (0.81 ≤ d ≤ 1.00). Post-hoc tests showed higher sprint velocity following RST and TPT (0.69 ≤ d ≤ 0.82) when compared to the control group, but no difference between RST and TPT. Pre-to-post changes amounted to 4.5% for RST [90%CI: (-1.1%;10.1%), d = 1.23] and 2.6% for TPT [90%CI: (0.4%;4.8%), d = 1.59]. Additionally, ground contact times during sprinting were shorter following RST and TPT (0.68 ≤ d ≤ 1.09) compared to the control group, but no difference between RST and TPT. Pre-to-post changes amounted to -6.3% for RST [90%CI: (-11.4%;-1.1%), d = 1.45) and -2.7% for TPT [90%CI: (-4.2%;-1.2%), d = 2.36]. Finally, effects for change-of

  10. Feasibility and effects of newly developed balance control trainer for mobility and balance in chronic stroke patients: a randomized controlled trial.

    Science.gov (United States)

    Lee, So Hyun; Byun, Seung Deuk; Kim, Chul Hyun; Go, Jin Young; Nam, Hyeon Uk; Huh, Jin Seok; Jung, Tae Du

    2012-08-01

    To investigate the feasibility and effects of balance training with a newly developed Balance Control Trainer (BCT) that applied the concept of vertical movement for the improvements of mobility and balance in chronic stroke patients. Forty chronic stroke patients were randomly assigned to an experimental or a control group. The experimental group (n=20) underwent training with a BCT for 20 minutes a day, 5 days a week for 4 weeks, in addition to concurrent conventional physical therapy. The control group (n=20) underwent only conventional therapy for 4 weeks. All participants were assessed by: the Functional Ambulation Categories (FAC), 10-meter Walking Test (10mWT), Timed Up and Go test (TUG), Berg Balance Scale (BBS), Korean Modified Barthel Index (MBI), and Manual Muscle Test (MMT) before training, and at 2 and 4 weeks of training. There were statistically significant improvements in all parameters except knee extensor power at 2 weeks of treatment, and in all parameters except MBI which showed further statistically significant progress in the experimental group over the next two weeks (pgait in ambulatory chronic stroke patients. Furthermore, it may provide additional benefits when used in conjunction with conventional therapies.

  11. Some Matrix Iterations for Computing Generalized Inverses and Balancing Chemical Equations

    Directory of Open Access Journals (Sweden)

    Farahnaz Soleimani

    2015-11-01

    Full Text Available An application of iterative methods for computing the Moore–Penrose inverse in balancing chemical equations is considered. With the aim to illustrate proposed algorithms, an improved high order hyper-power matrix iterative method for computing generalized inverses is introduced and applied. The improvements of the hyper-power iterative scheme are based on its proper factorization, as well as on the possibility to accelerate the iterations in the initial phase of the convergence. Although the effectiveness of our approach is confirmed on the basis of the theoretical point of view, some numerical comparisons in balancing chemical equations, as well as on randomly-generated matrices are furnished.

  12. Energy balance in TM-1-MH Tokamak (ohmical heating)

    Science.gov (United States)

    Stoeckel, J.; Koerbel, S.; Kryska, L.; Kopecky, V.; Dadalec, V.; Datlov, J.; Jakubka, K.; Magula, P.; Zacek, F.; Pereverzev, G. V.

    1981-10-01

    Plasma in the TM-1-MH Tokamak was experimentally studied in the parameter range: tor. mg. field B = 1,3 T, plasma current I sub p = 14 kA, electron density N sub E 3.10 to the 19th power cubic meters. The two numerical codes are available for the comparison with experimental data. TOKATA-code solves simplified energy balance equations for electron and ion components. TOKSAS-code solves the detailed energy balance of the ion component.

  13. Price-based control of electrical power systems

    NARCIS (Netherlands)

    Jokic, A.; Lazar, M.; Bosch, van den P.P.J.; Negenborn, R.R.; Lukszo, Z.; Hellendorn, H.

    2010-01-01

    In this chapter we present the price-based control as a suitable approach to solve some of the challenging problems facing future, market-based power sys tems. On the example of economically optimal power balance and transmission network congestion control, we present how global objectives and

  14. Claim Your Powers.

    Science.gov (United States)

    Update on Law-Related Education, 1986

    1986-01-01

    Presents a game which has students interpret Articles I, II, and III of the U.S. Constitution to understand the allocation of powers among the 3 branches of government. The game helps students understand the interaction between the 3 branches of government, stressing the separation of powers and the system of checks and balances. (JDH)

  15. EFFECT OF NEUROMUSCULAR TRAINING ON BALANCE AMONG UNIVERSITY ATHLETES

    Directory of Open Access Journals (Sweden)

    Mohansundar Sankaravel

    2016-06-01

    Full Text Available Background: Proprioceptive deficiency followed by lateral ankle sprain leads to poor balance is not uncommon. It has been linked with increased injury risk among young athletes. Introducing neuromuscular training programs for this have been believed as one of the means of injury prevention. Hence, this study was aimed to determine the effects of six weeks progressive neuromuscular training (PNM Training on static balance gains among the young athletes with a previous history of ankle sprains. Methods: This study was an experimental study design, with pre and post test method to determine the effects of PNM Training on static balance gains. All data were collected at university’s sports rehabilitation lab before and after six weeks of intervention period. There were 20 male and female volunteer young athletes (20.9 ± 0.85 years of age with a previous history of ankle sprain involving various sports were recruited from the University community. All the subjects were participated in a six week PNM Training that included stability, strength and power training. Outcome measures were collected by calculating the errors on balance error scoring system made by the athletes on static balance before and after the six weeks of intervention period. Static balance was tested in firm and foam surfaces and recorded accordingly. Results: The researchers found a significant decrease (2.40 ± 0.82 in total errors among the samples at the post test compared with their pre test (P >0.05. Conclusions: The study demonstrates that a PNM Training can improve the static balance on both the firm and foam surfaces among the young athletes with a previous history of ankle sprains.

  16. Border Biofuels Limited - maintaining a sense of balance

    International Nuclear Information System (INIS)

    Seed, J.M.

    1994-01-01

    A brief description is given of a renewable energy initiative to grow wood fuel in the Scottish and English border region. The aim is to develop a new rural industry based on wood fuel feeding a power plant in a central location in the Borders area. The financial arrangements to grow short rotation coppice are outlined as are the environmental impacts and energy balance. (UK)

  17. Classification of reserve capacity in future power systems

    NARCIS (Netherlands)

    Frunt, J.; Kling, W.L.; Myrzik, J.M.A.

    2009-01-01

    In electrical power systems must always be a balance between supply and demand. Any imbalance will result in a frequency deviation. To reduce the imbalance to zero, ancillary services for balancing are in use. Ancillary services are characterised by their deployment time and their capacity. By using

  18. National Assessment of Energy Storage for Grid Balancing and Arbitrage: Phase 1, WECC

    Energy Technology Data Exchange (ETDEWEB)

    Kintner-Meyer, Michael CW; Balducci, Patrick J.; Colella, Whitney G.; Elizondo, Marcelo A.; Jin, Chunlian; Nguyen, Tony B.; Viswanathan, Vilayanur V.; Zhang, Yu

    2012-06-01

    To examine the role that energy storage could play in mitigating the impacts of the stochastic variability of wind generation on regional grid operation, the Pacific Northwest National Laboratory (PNNL) examined a hypothetical 2020 grid scenario in which additional wind generation capacity is built to meet renewable portfolio standard targets in the Western Interconnection. PNNL developed a stochastic model for estimating the balancing requirements using historical wind statistics and forecasting error, a detailed engineering model to analyze the dispatch of energy storage and fast-ramping generation devices for estimating size requirements of energy storage and generation systems for meeting new balancing requirements, and financial models for estimating the life-cycle cost of storage and generation systems in addressing the future balancing requirements for sub-regions in the Western Interconnection. Evaluated technologies include combustion turbines, sodium sulfur (Na-S) batteries, lithium ion batteries, pumped-hydro energy storage, compressed air energy storage, flywheels, redox flow batteries, and demand response. Distinct power and energy capacity requirements were estimated for each technology option, and battery size was optimized to minimize costs. Modeling results indicate that in a future power grid with high-penetration of renewables, the most cost competitive technologies for meeting balancing requirements include Na-S batteries and flywheels.

  19. Computational Efficiency of Economic MPC for Power Systems Operation

    DEFF Research Database (Denmark)

    Standardi, Laura; Poulsen, Niels Kjølstad; Jørgensen, John Bagterp

    2013-01-01

    In this work, we propose an Economic Model Predictive Control (MPC) strategy to operate power systems that consist of independent power units. The controller balances the power supply and demand, minimizing production costs. The control problem is formulated as a linear program that is solved...

  20. Balanced Design of Safety Systems of CAREM Advanced Reactor

    International Nuclear Information System (INIS)

    Grinblat, Pablo; Gimenez, Marcelo; Schlamp, Miguel

    2003-01-01

    Nuclear Power Plants must meet the performance that the market and the population demand in order to be part of the electricity supply industry.It is related mainly with the results of reactor's economy and safety.New advances in the methodology developed for reactor economic optimization analyzing its safety at an early engineering stage, aiming at balancing these important features of the design, are presented in this work.In particular, the coupling that appears when dimensioning the Emergency Injection System, the Residual Heat Removal System and the containment height of CAREM reactor is described.The new models appended to the computer code that embodies the methodology to balance de designs are shown.Finally the results obtained with the optimizations when applying it are presented.Furthermore, a criterion to establish the maximal diameter for acceptable breaks in RPV's penetrations arises from this work.The application of the methodology and the computer code developed turns out to prove the advantages they provide to reactor design so that the plants are properly balanced and optimized

  1. Drivers of imbalance cost of wind power

    DEFF Research Database (Denmark)

    Obersteiner, C.; Siewierski, T.; Andersen, Anders

    2010-01-01

    In Europe an increasing share of wind power is sold on the power market. Therefore more and more wind power generators become balancing responsible and face imbalance cost that reduce revenues from selling wind power. A comparison of literature illustrates that the imbalance cost of wind power...... varies in a wide range. To explain differences we indentify parameters influencing imbalance cost and compare them for case studies in Austria, Denmark and Poland. Besides the wind power forecast error also the correlation between imbalance and imbalance price influences imbalance cost significantly...... of imperfect forecast is better suited to reflect real cost incurred due to inaccurate wind power forecasts....

  2. Dynamic-energetic balance of agricultural tractors: active systems for the measurement of the power requirements in static tests and under field conditions

    Directory of Open Access Journals (Sweden)

    Daniele Pochi

    2013-09-01

    Full Text Available Modern tractors are characterized by the introduction of devices designed to increase the operative performances of the machines, such as systems for monitoring and controlling various functions (through a massive use of electronics and hydraulics, or deputed to improve the comfort of the driver (paying more attention to ergonomics, air-conditioning, noise and vibration. Such devices need energy to be operated, affecting the energetic balance of the tractor. In this context, the availability of suitable methodologies and instrumental systems could be useful to provide objective, accurate and reliable measurements of the performances of the tractors under different conditions, also considering the power requirements from ancillary services and/or simulating the coupling with operating machines. The tests on the performances of tractors are now made using different methods, including the trial codes issued by the OECD Codes. Beyond their undoubted validity, they fix standard test conditions that often do not adequately represent the operative reality, so that, much remains to investigate on the actual performances provided by the tractors. From this point of view and with reference to fixed point tests, a test bench was developed for the measurement of the power required by various devices, such as transmission and air conditioning. It was used in experimental tests on a tracked tractor and on a wheeled tractor, aimed at validating the test device, measuring the power absorption related to the rotational speed of the organs of propulsion and to the characteristics curves, in order to quantify the power drawn by the transmission and by the air conditioning and assess the residual power for other tractor functions. As to field conditions, a study is being conducted at CRA-ING, within the project PTO (Mi.P.A.A.F., to develop a mobile test bench aimed at evaluating the power required by different operations, such as self displacement, traction, use of

  3. Fractional power operation of tokamak reactors

    International Nuclear Information System (INIS)

    Mau, T.K.; Vold, E.L.; Conn, R.W.

    1986-01-01

    Methods to operate a tokamak fusion reactor at fractions of its rated power, identify the more effective control knobs and assess the impact of the requirements of fractional power operation on full power reactor design are explored. In particular, the role of burn control in maintaining the plasma at thermal equilibrium throughout these operations is studied. As a prerequisite to this task, the critical physics issues relevant to reactor performance predictions are examined and some insight into their impact on fractional power operation is offered. The basic tool of analysis consists of a zero-dimensional (0-D) time-dependent plasma power balance code which incorporates the most advanced data base and models in transport and burn plasma physics relevant to tokamaks. Because the plasma power balance is dominated by the transport loss and given the large uncertainty in the confinement model, the authors have studied the problem for a wide range of energy confinement scalings. The results of this analysis form the basis for studying the temporal behavior of the plasma under various thermal control mechanisms. Scenarios of thermally stable full and fractional power operations have been determined for a variety of transport models, with either passive or active feedback burn control. Important power control parameters, such as gas fueling rate, auxiliary power and other plasma quantities that affect transport losses, have also been identified. The results of these studies vary with the individual transport scaling used and, in particular, with respect to the effect of alpha heating power on confinement

  4. Imbalance costs in the Swedish system with large amounts of wind power

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, Fredrik; Neimane, Viktoria [Vattenfall Research and Development AB, Stockholm (Sweden)

    2009-07-01

    The well-known concerns about wind power are related to its intermittent nature and difficulty to make exact forecasts. The expected increase in balancing and reserve requirements due to wind power has been investigated in several studies. This paper takes the next step in studying integration of large amounts of wind power in Sweden. Several wind power producers' and corresponding balance providers' perspective is taken and their imbalance costs modeled. Larger producers having wind power spread over larger geographical areas will have lower relative costs than producers having their units concentrated within limited geographical area. Possibilities of the wind power producers to reduce the imbalance costs by acting on after sales market are exposed and compared. (orig.)

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

    Directory of Open Access Journals (Sweden)

    Abdul Basit

    2014-10-01

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

  6. Response of Cryolite-Based Bath to a Shift in Heat Input/output Balance

    Science.gov (United States)

    Liu, Jingjing; Taylor, Mark; Dorreen, Mark

    2017-04-01

    A technology for low amperage potline operation is now recognized as a competitive advantage for the aluminum smelting industry in order to align smelter operations with the power and aluminum price markets. This study investigates the cryolite-based bath response to heat balance shifts when the heat extraction from the bath is adjusted to different levels in a laboratory analogue. In the analogue experiments, the heat balance shift is driven by a graphite `cold finger' heat exchanger, which can control the heat extraction from the analogue, and a corresponding change in heat input from the furnace which maintains the control temperature of the lab "cell." This paper reports the first experimental results from shifting the steady state of the lab cell heat balance, and investigates the effects on the frozen ledge and bath superheat. The lab cell energy balances are compared with energy balances in a published industrial cell model.

  7. Design and operation of power systems with large amounts of wind power. Final summary report, IEA WIND Task 25, Phase two 2009 - 2011

    Energy Technology Data Exchange (ETDEWEB)

    Holttinen, H.; Kiviluoma, J. [VTT Technical Research Centre of Finland, Espoo (Finland); Robitaille, A. [Hydro Quebec, Montreal QC (Canada)] [and others

    2013-01-15

    This report provides a summary of the results from recent wind integration studies. The studies address concerns about the impact of wind power's variability and uncertainty on power system reliability and costs as well as grid reinforcement needs. Quantifiable results are presented as summary graphs: results as a MW-increase in reserve requirements, or euro/MWh increase in balancing costs, or results for capacity value of wind power. Other results are briefly summarised, together with existing experience on the issues. There is already significant experience in integrating wind power in power systems. The mitigation of wind power impacts include more flexible operational methods, incentivising flexibility in other generating plants, increasing interconnection to neighbouring regions, and application of demand-side flexibility. Electricity storage is still not as cost effective in larger power systems as other means of flexibility, but is already seeing initial applications in places with limited transmission. Electricity markets, with cross-border trade of intra-day and balancing resources and emerging ancillary services markets, are seen as promising for future large penetration levels for wind power. (orig.)

  8. Work-Life Balance Practices in Nigeria: A Comparison of Three Sectors

    Directory of Open Access Journals (Sweden)

    Ojo Ibiyinka Stella

    2014-06-01

    Full Text Available The study investigates the concept of work-life balance (WLB policies and practices in three sectors of the Nigerian Economy namely the Banking, Educational and Power Sector. The types of WLB initiatives available in the three sectors were explored and the barriers to implementation of the WLB initiatives were identified. This research implored quantitative methods to investigate the work-life balance practices in three sectors of the Nigerian Economy. This was achieved using an in-depth case study analysis of these sectors. The data set comprised of responses from both managers and employees in the Banking sector with five hundred and eighty six copies of the questionnaire retrieved. The Educational sector comprised of both managers and employees with five hundred and thirty one copies of the questionnaire retrieved; while five hundred and seven copies retrieved from the Power Sector. The findings reveal that there is diversity in terms of how respondents perceive the concept of Work-Life Balance. There is a wide gap between corporate WLB practices and employees’ understanding of the concept; the paper suggests some policy implications which would aid the implementation of WLB policies in the studied sectors. This study also suggests direction for future research.

  9. The combination of plyometric and balance training improves sprint and shuttle run performances more often than plyometric-only training with children.

    Science.gov (United States)

    Chaouachi, Anis; Othman, Aymen Ben; Hammami, Raouf; Drinkwater, Eric J; Behm, David G

    2014-02-01

    Because balance is not fully developed in children and studies have shown functional improvements with balance only training studies, a combination of plyometric and balance activities might enhance static balance, dynamic balance, and power. The objective of this study was to compare the effectiveness of plyometric only (PLYO) with balance and plyometric (COMBINED) training on balance and power measures in children. Before and after an 8-week training period, testing assessed lower-body strength (1 repetition maximum leg press), power (horizontal and vertical jumps, triple hop for distance, reactive strength, and leg stiffness), running speed (10-m and 30-m sprint), static and dynamic balance (Standing Stork Test and Star Excursion Balance Test), and agility (shuttle run). Subjects were randomly divided into 2 training groups (PLYO [n = 14] and COMBINED [n = 14]) and a control group (n = 12). Results based on magnitude-based inferences and precision of estimation indicated that the COMBINED training group was considered likely to be superior to the PLYO group in leg stiffness (d = 0.69, 91% likely), 10-m sprint (d = 0.57, 84% likely), and shuttle run (d = 0.52, 80% likely). The difference between the groups was unclear in 8 of the 11 dependent variables. COMBINED training enhanced activities such as 10-m sprints and shuttle runs to a greater degree. COMBINED training could be an important consideration for reducing the high velocity impacts of PLYO training. This reduction in stretch-shortening cycle stress on neuromuscular system with the replacement of balance and landing exercises might help to alleviate the overtraining effects of excessive repetitive high load activities.

  10. Acoustic power balance in lined ducts

    Science.gov (United States)

    Eversman, W.

    1979-01-01

    It is shown that the two common definitions of acoustic energy density and intensity in uniform unlined ducts carrying uniform flow are compatible to the extent that both energy densities can be used in an appropriate variational principle to derive the convected wave equation. When the duct walls are lined both energy densities must be modified to account for the wall energy density. This results in a new energy conservation equation which utilizes a modified definition of axial power and accounts for wall dissipation. Computations in specific cases demonstrate the validity of the modified acoustic energy relation.

  11. Within Session Sequence of Balance and Plyometric Exercises Does Not Affect Training Adaptations with Youth Soccer Athletes.

    Science.gov (United States)

    Chaouachi, Mehdi; Granacher, Urs; Makhlouf, Issam; Hammami, Raouf; Behm, David G; Chaouachi, Anis

    2017-03-01

    The integration of balance and plyometric training has been shown to provide significant improvements in sprint, jump, agility, and other performance measures in young athletes. It is not known if a specific within session balance and plyometric exercise sequence provides more effective training adaptations. The objective of the present study was to investigate the effects of using a sequence of alternating pairs of exercises versus a block (series) of all balance exercises followed by a block of plyometric exercises on components of physical fitness such as muscle strength, power, speed, agility, and balance. Twenty-six male adolescent soccer players (13.9 ± 0.3 years) participated in an 8-week training program that either alternated individual balance (e.g., exercises on unstable surfaces) and plyometric (e.g., jumps, hops, rebounds) exercises or performed a block of balance exercises prior to a block of plyometric exercises within each training session. Pre- and post-training measures included proxies of strength, power, agility, sprint, and balance such as countermovement jumps, isometric back and knee extension strength, standing long jump, 10 and 30-m sprints, agility, standing stork, and Y-balance tests. Both groups exhibited significant, generally large magnitude (effect sizes) training improvements for all measures with mean performance increases of approximately >30%. There were no significant differences between the training groups over time. The results demonstrate the effectiveness of combining balance and plyometric exercises within a training session on components of physical fitness with young adolescents. The improved performance outcomes were not significantly influenced by the within session exercise sequence.

  12. Within Session Sequence of Balance and Plyometric Exercises Does Not Affect Training Adaptations with Youth Soccer Athletes

    Directory of Open Access Journals (Sweden)

    Mehdi Chaouachi, Urs Granacher, Issam Makhlouf, Raouf Hammami, David G Behm, Anis Chaouachi

    2017-03-01

    Full Text Available The integration of balance and plyometric training has been shown to provide significant improvements in sprint, jump, agility, and other performance measures in young athletes. It is not known if a specific within session balance and plyometric exercise sequence provides more effective training adaptations. The objective of the present study was to investigate the effects of using a sequence of alternating pairs of exercises versus a block (series of all balance exercises followed by a block of plyometric exercises on components of physical fitness such as muscle strength, power, speed, agility, and balance. Twenty-six male adolescent soccer players (13.9 ± 0.3 years participated in an 8-week training program that either alternated individual balance (e.g., exercises on unstable surfaces and plyometric (e.g., jumps, hops, rebounds exercises or performed a block of balance exercises prior to a block of plyometric exercises within each training session. Pre- and post-training measures included proxies of strength, power, agility, sprint, and balance such as countermovement jumps, isometric back and knee extension strength, standing long jump, 10 and 30-m sprints, agility, standing stork, and Y-balance tests. Both groups exhibited significant, generally large magnitude (effect sizes training improvements for all measures with mean performance increases of approximately >30%. There were no significant differences between the training groups over time. The results demonstrate the effectiveness of combining balance and plyometric exercises within a training session on components of physical fitness with young adolescents. The improved performance outcomes were not significantly influenced by the within session exercise sequence.

  13. Voltage balancing strategies for serial connection of microbial fuel cells

    Science.gov (United States)

    Khaled, Firas; Ondel, Olivier; Allard, Bruno; Buret, François

    2015-07-01

    The microbial fuel cell (MFC) converts electrochemically organic matter into electricity by means of metabolisms of bacteria. The MFC power output is limited by low voltage and low current characteristics in the range of microwatts or milliwatts per litre. In order to produce a sufficient voltage level (>1.5 V) and sufficient power to supply real applications such as autonomous sensors, it is necessary to either scale-up one single unit or to connect multiple units together. Many topologies of connection are possible as the serial association to improve the output voltage, or the parallel connection to improve the output current or the series/parallel connection to step-up both voltage and current. The association of MFCs in series is a solution to increase the voltage to an acceptable value and to mutualize the unit's output power. The serial association of a large number of MFCs presents several issues. The first one is the hydraulic coupling among MFCs when they share the same substrate. The second one is the dispersion between generators that lead to a non-optimal stack efficiency because the maximum power point (MPP) operation of all MFCs is not permitted. Voltage balancing is a solution to compensate non-uniformities towards MPP. This paper presents solutions to improve the efficiency of a stack of serially connected MFCs through a voltage-balancing circuit. Contribution to the topical issue "Electrical Engineering Symposium (SGE 2014)", edited by Adel Razek

  14. Nuclear power economic database

    International Nuclear Information System (INIS)

    Ding Xiaoming; Li Lin; Zhao Shiping

    1996-01-01

    Nuclear power economic database (NPEDB), based on ORACLE V6.0, consists of three parts, i.e., economic data base of nuclear power station, economic data base of nuclear fuel cycle and economic database of nuclear power planning and nuclear environment. Economic database of nuclear power station includes data of general economics, technique, capital cost and benefit, etc. Economic database of nuclear fuel cycle includes data of technique and nuclear fuel price. Economic database of nuclear power planning and nuclear environment includes data of energy history, forecast, energy balance, electric power and energy facilities

  15. Power and fairness in a generalized ultimatum game.

    Directory of Open Access Journals (Sweden)

    Giovanni Luca Ciampaglia

    Full Text Available Power is the ability to influence others towards the attainment of specific goals, and it is a fundamental force that shapes behavior at all levels of human existence. Several theories on the nature of power in social life exist, especially in the context of social influence. Yet, in bargaining situations, surprisingly little is known about its role in shaping social preferences. Such preferences are considered to be the main explanation for observed behavior in a wide range of experimental settings. In this work, we set out to understand the role of bargaining power in the stylized environment of a Generalized Ultimatum Game (GUG. We modify the payoff structure of the standard Ultimatum Game (UG to investigate three situations: two in which the power balance is either against the proposer or against the responder, and a balanced situation. We find that other-regarding preferences, as measured by the amount of money donated by participants, do not change with the amount of power, but power changes the offers and acceptance rates systematically. Notably, unusually high acceptance rates for lower offers were observed. This finding suggests that social preferences may be invariant to the balance of power and confirms that the role of power on human behavior deserves more attention.

  16. Optimal Power Flow in Microgrids with Energy Storage

    DEFF Research Database (Denmark)

    Levron, Yoash; Guerrero, Josep M.; Beck, Yuval

    2013-01-01

    Energy storage may improve power management in microgrids that include renewable energy sources. The storage devices match energy generation to consumption, facilitating a smooth and robust energy balance within the microgrid. This paper addresses the optimal control of the microgrid’s energy...... storage devices. Stored energy is controlled to balance power generation of renewable sources to optimize overall power consumption at the microgrid point of common coupling. Recent works emphasize constraints imposed by the storage device itself, such as limited capacity and internal losses. However...

  17. Responses of Lithium-Modified Bath to a Shift in Heat Input/Output Balance and Observation of Freeze-Lining Formation During the Heat Balance Shift

    Science.gov (United States)

    Liu, Jingjing; Taylor, Mark; Dorreen, Mark

    2018-02-01

    In the aluminum electrolysis process, new industrial aluminum/electricity power markets demand a new cell technology to extend the cell heat balance and amperage operating window of smelters by shifting the steady states. The current work investigates the responses of lithium-modified bath system when the input/output balance is shifted in a laboratory analogue to the industrial heat balance shift. Li2CO3 is added to the cryolite-AlF3-CaF2-Al2O3 system as a bath modifier. A freeze deposit is formed on a `cold finger' dipped into the bath and investigated by X-ray diffraction analysis and electron probe X-ray microanalysis. The macro- and micro-structure of the freeze lining varies with the bath superheat (bath temperature minus bath liquidus temperature) and an open crystalline layer with entrapped liquid dominates the freeze thickness. Compared with the cryolite-AlF3-CaF2-Al2O3 bath system, the lithium-modified bath freeze is more sensitive to the heat balance shift. This freeze investigation provides primary information to understand the variation of the side ledge in an industrial cell when the lithium-modified bath system is used.

  18. Effects of Supervised vs. Unsupervised Training Programs on Balance and Muscle Strength in Older Adults: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Lacroix, André; Hortobágyi, Tibor; Beurskens, Rainer; Granacher, Urs

    2017-11-01

    Balance and resistance training can improve healthy older adults' balance and muscle strength. Delivering such exercise programs at home without supervision may facilitate participation for older adults because they do not have to leave their homes. To date, no systematic literature analysis has been conducted to determine if supervision affects the effectiveness of these programs to improve healthy older adults' balance and muscle strength/power. The objective of this systematic review and meta-analysis was to quantify the effectiveness of supervised vs. unsupervised balance and/or resistance training programs on measures of balance and muscle strength/power in healthy older adults. In addition, the impact of supervision on training-induced adaptive processes was evaluated in the form of dose-response relationships by analyzing randomized controlled trials that compared supervised with unsupervised trials. A computerized systematic literature search was performed in the electronic databases PubMed, Web of Science, and SportDiscus to detect articles examining the role of supervision in balance and/or resistance training in older adults. The initially identified 6041 articles were systematically screened. Studies were included if they examined balance and/or resistance training in adults aged ≥65 years with no relevant diseases and registered at least one behavioral balance (e.g., time during single leg stance) and/or muscle strength/power outcome (e.g., time for 5-Times-Chair-Rise-Test). Finally, 11 studies were eligible for inclusion in this meta-analysis. Weighted mean standardized mean differences between subjects (SMD bs ) of supervised vs. unsupervised balance/resistance training studies were calculated. The included studies were coded for the following variables: number of participants, sex, age, number and type of interventions, type of balance/strength tests, and change (%) from pre- to post-intervention values. Additionally, we coded training according

  19. On balanced minimal repeated measurements designs

    Directory of Open Access Journals (Sweden)

    Shakeel Ahmad Mir

    2014-10-01

    Full Text Available Repeated Measurements designs are concerned with scientific experiments in which each experimental unit is assigned more than once to a treatment either different or identical. This class of designs has the property that the unbiased estimators for elementary contrasts among direct and residual effects are obtainable. Afsarinejad (1983 provided a method of constructing balanced Minimal Repeated Measurements designs p < t , when t is an odd or prime power, one or more than one treatment may occur more than once in some sequences and  designs so constructed no longer remain uniform in periods. In this paper an attempt has been made to provide a new method to overcome this drawback. Specifically, two cases have been considered                RM[t,n=t(t-t/(p-1,p], λ2=1 for balanced minimal repeated measurements designs and  RM[t,n=2t(t-t/(p-1,p], λ2=2 for balanced  repeated measurements designs. In addition , a method has been provided for constructing              extra-balanced minimal designs for special case RM[t,n=t2/(p-1,p], λ2=1.

  20. Diagnosis of excessive vibration signals of two-pole generator rotors in balancing

    International Nuclear Information System (INIS)

    Park, Jong Po

    2000-01-01

    Cause of excessive vibration with twice the rotational speed of a two-pole generator rotor for the fossil power plants was investigated. The two-pole generator rotor, treated as a typically asymmetric rotor in vibration analysis, produces asynchronous vibration with twice the rotational speed, sub-harmonic critical speeds, and potentially unstable operating zones due to its own inertia and/or stiffness asymmetry. This paper introduces a practical balancing procedure, and presents the results of the investigation on sources of the excessive vibration based on the experimental vibration data of the asymmetric two-pole rotor in balancing

  1. Lack of Effect of Typical Rapid-Weight-Loss Practices on Balance and Anaerobic Performance in Apprentice Jockeys.

    Science.gov (United States)

    Cullen, SarahJane; Dolan, Eimear; O Brien, Kate; McGoldrick, Adrian; Warrington, Giles

    2015-11-01

    Balance and anaerobic performance are key attributes related to horse-racing performance, but research on the impact of making weight for racing on these parameters remains unknown. The purpose of this study was to investigate the effects of rapid weight loss in preparation for racing on balance and anaerobic performance in a group of jockeys. Twelve apprentice male jockeys and 12 age- and gender-matched controls completed 2 trials separated by 48 h. In both trials, body mass, hydration status, balance, and anaerobic performance were assessed. Between the trials, the jockeys reduced body mass by 4% using weight-loss methods typically adopted in preparation for racing, while controls maintained body mass through typical daily dietary and physical activity habits. Apprentice jockeys decreased mean body mass by 4.2% ± 0.3% (P balance, on the left or right side, or in peak power, mean power, or fatigue index were reported between the trials in either group. Results from this study indicate that a 4% reduction in body mass in 48 h through the typical methods employed for racing, in association with an increase in dehydration, resulted in no impairments in balance or anaerobic performance. Further research is required to evaluate performance in a sport-specific setting and to investigate the specific physiological mechanisms involved.

  2. Comparison of traditional and recent approaches in the promotion of balance and strength in older adults.

    Science.gov (United States)

    Granacher, Urs; Muehlbauer, Thomas; Zahner, Lukas; Gollhofer, Albert; Kressig, Reto W

    2011-05-01

    Demographic change in industrialized countries produced an increase in the proportion of elderly people in our society, resulting in specific healthcare challenges. One such challenge is how to effectively deal with the increased risk of sustaining a fall and fall-related injuries in old age. Deficits in postural control and muscle strength represent important intrinsic fall risk factors. Thus, adequate training regimens need to be designed and applied that have the potential to reduce the rate of falling in older adults by countering these factors. Therefore, the purpose of this review is to compare traditional and recent approaches in the promotion of balance and strength in older adults. Traditionally, balance and resistance training programmes proved to be effective in improving balance and strength, and in reducing the number of falls. Yet, it was argued that these training protocols are not specific enough to induce adaptations in neuromuscular capacities that are specifically needed in actual balance-threatening situations (e.g. abilities to recover balance and to produce force explosively). Recent studies indicated that perturbation-based or multitask balance training and power/high-velocity resistance training have the potential to improve these specific capacities because they comply with the principle of training specificity. In fact, there is evidence that these specifically tailored training programmes are more effective in improving balance recovery mechanisms and muscle power than traditional training protocols. A few pilot studies have even shown that these recently designed training protocols have an impact on the reduction of fall incidence rate in older adults. Further research is needed to confirm these results and to elucidate the underlying mechanisms responsible for the adaptive processes.

  3. Tax balance in agribusiness as a type of special balance

    Directory of Open Access Journals (Sweden)

    Milojević Ivan

    2015-01-01

    Full Text Available The tendency of continuous compounding of business processes inevitably leads to application of increasingly complex instruments for the purposes of financial reporting in agribusiness. In this system the existential place and role of individual elements that alter the existing and acquire new functions comes into question. Balancing implies a regulated and consistent system in which every change leads to the creation of new relations and changing already established relationships. In this regard, in this paper we will focus on the place and role of tax balance in the group of special balances in agribusiness, as a very significant group of accounting instruments. Displaying information for users and situations in which they are used, balances gain their place in this classification. For the purposes of applying financial instruments, referring primarily to balances in agribusiness, it is necessary to know the way of their classification according to their functions. From this aspect, tax balance in agribusiness is a specific report, both in terms of its formal and material structure, which gives it the basis to belong to ordinary as well as special types of balances in agribusiness.

  4. Midwest gas and power markets, hubs, pipelines, and interconnects

    International Nuclear Information System (INIS)

    Wirick, J.

    2001-01-01

    The existing interstate pipelines and proposed pipeline projects for the Chicago hub area were illustrated. The presentation explained why energy suppliers in the current competitive market need to balance and manage energy and transportation services for gas-fired power generators in terms of hourly winter and summer peaking services. The new infrastructure of the energy market will include new pipelines, storage and balancing to meet the ever increasing power demand. One of the options to meet power demand is to increase natural gas supply, transportation, storage, and hourly balancing capabilities. Other options are to build nuclear or coal-fired power generating facilities, or to go with renewables such as solar and wind power. Energy conservation and the reduction of natural gas usage per capita is another option to eliminate blackouts. This presentation also addressed the role that local distribution companies (LDC) and unbundling will play in the choice of these options. tabs., figs

  5. Wind power forecasting accuracy and uncertainty in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Holttinen, H.; Miettinen, J.; Sillanpaeae, S.

    2013-04-15

    Wind power cannot be dispatched so the production levels need to be forecasted for electricity market trading. Lower prediction errors mean lower regulation balancing costs, since relatively less energy needs to go through balance settlement. From the power system operator point of view, wind power forecast errors will impact the system net imbalances when the share of wind power increases, and more accurate forecasts mean less regulating capacity will be activated from the real time Regulating Power Market. In this publication short term forecasting of wind power is studied mainly from a wind power producer point of view. The forecast errors and imbalance costs from the day-ahead Nordic electricity markets are calculated based on real data from distributed wind power plants. Improvements to forecasting accuracy are presented using several wind forecast providers, and measures for uncertainty of the forecast are presented. Aggregation of sites lowers relative share of prediction errors considerably, up to 60%. The balancing costs were also reduced up to 60%, from 3 euro/MWh for one site to 1-1.4 euro/MWh to aggregate 24 sites. Pooling wind power production for balance settlement will be very beneficial, and larger producers who can have sites from larger geographical area will benefit in lower imbalance costs. The aggregation benefits were already significant for smaller areas, resulting in 30-40% decrease in forecast errors and 13-36% decrease in unit balancing costs, depending on the year. The resulting costs are strongly dependent on Regulating Market prices that determine the prices for the imbalances. Similar level of forecast errors resulted in 40% higher imbalance costs for 2012 compared with 2011. Combining wind forecasts from different Numerical Weather Prediction providers was studied with different combination methods for 6 sites. Averaging different providers' forecasts will lower the forecast errors by 6% for day-ahead purposes. When combining

  6. The condition monitoring system of turbine system components for nuclear power plants

    International Nuclear Information System (INIS)

    Ono, Shigetoshi

    2013-01-01

    The thermal and nuclear power plants have been imposed a stable supply of electricity. To certainly achieve this, we built the plant condition monitoring system based on the heat and mass balance calculation. If there are some performance changes on the turbine system components of their power plants, the heat and mass balance of the turbine system will change. This system has ability to detect the abnormal signs of their components by finding the changes of the heat and mass balance. Moreover we note that this system is built for steam turbine cycle operating with saturated steam conditions. (author)

  7. Balance-of-plant outage availability study. Phase I. Extension report

    International Nuclear Information System (INIS)

    Thomasson, F.R.

    1978-09-01

    After completion of the Phase 1 Refueling Outage Availability Study, Babcock and Wilcox and the U.S. Department of Energy entered into a supplemental agreement to perform a balance-of-plant maintenance, inspection, and test study with the cooperation of Duke Power Company and Arkansas Power and Light Company. The objectives were (1) to expand the Phase 1 data base, including balance-of-plant activities, to reduce outage time and increase plant availability and (2) to conduct an onsite review of plant maintenance, practices to complement the utility efforts in reducing outage time and increasing on-line operational time. Data were obtained from (1) observations during the 1977 refueling outage at Oconee 3, (2) review of maintenance practices during the Arkansas Nuclear One, Unit 1, operational cycle in 1977, and (3) selected observations of the 1978 refueling outage at ANO-1. Accumulated data were then reviewed and analyzed to produce a list of improvement recommendations for Oconee 3 and ANO-1 that can be generically applied to plants of similar design and construction

  8. Phase control of the transient resonance of the automatic ball balancer

    Science.gov (United States)

    Michalczyk, Jerzy; Pakuła, Sebastian

    2016-05-01

    Hazards related to undesired increases of vibration amplitudes in transient resonance of vibroinsulated rotor systems with automatic ball balancer (ABB) are discussed in the paper. The application of the phase control method with taking into account the limited drive power is proposed for these amplitudes reduction. The high efficiency of this approach is indicated.

  9. A question of balance: Kinetic balance for electrons and positrons

    International Nuclear Information System (INIS)

    Dyall, Kenneth G.

    2012-01-01

    Graphical abstract: Kinetic balance for both electrons and positrons is achieved by applying the correct relation for positive and negative energy states separately and then using the electron and positron eigensolutions from the separate diagonalizations of the Hamiltonian as a dual basis. Highlights: ► Kinetic balance for electrons and positrons is achieved in a dual atomic basis. ► Dual atomic balance alleviates, but does not eliminate, energy prolapse. ► Positron affinities converge quicker with basis set size with dual atomic balance. - Abstract: The kinetic balance criterion used in current relativistic basis set codes is satisfied by the electron solutions of the Dirac equation, but not the positron solutions. A proposal for applying kinetic balance to both sets of solutions is presented. The method is applied along with “normal” kinetic balance to one-electron systems, to investigate its possible relation to prolapse, and to the positron affinity of F − , to investigate the kinetic energy deficiency for positron solutions. The new method reduces but does not eliminate prolapse for energy-optimized basis sets, and provides faster and smoother convergence with basis set size for the positron affinity.

  10. Integration of wind power in the liberalized Dutch electricity market

    NARCIS (Netherlands)

    Ummels, B.C.; Gibescu, M.; Kling, W.L.; Paap, G.C.

    2006-01-01

    Wind power is becoming a large-scale electricity generation technology in a number of European countries, including the Netherlands.Owing to the variability and unpredictability of wind power production, large-scale wind power can be foreseen to have large consequences for balancing generation and

  11. Allocation of reactive power support, active loss balancing and demand interruption ancillary services in MicroGrids

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Mario Helder [Departamento de Engenharia Electrotecnica, Instituto Politecnico de Tomar, Quinta do Contador, Estrada da Serra, 2300 Tomar (Portugal); Saraiva, Joao Tome [INESC Porto and Faculdade de Engenharia da Universidade do Porto, Campus da FEUP, Rua Dr. Roberto Frias, 4200 - 465 Porto (Portugal)

    2010-10-15

    MicroGrids represent a new paradigm for the operation of distribution systems and there are several advantages as well as challenges regarding their development. One of the advantages is related with the participation of MicroGrid agents in electricity markets and in the provision of ancillary services. This paper describes two optimization models to allocate three ancillary services among MicroGrid agents - reactive power/voltage control, active loss balancing and demand interruption. These models assume that MicroGrid agents participate in the day-ahead market sending their bids to the MicroGrid Central Controller, MGCC, that acts as an interface with the Market Operator. Once the Market Operator returns the economic dispatch of the MicroGrid agents, the MGCC checks its technical feasibility (namely voltage magnitude and branch flow limits) and activates an adjustment market to change the initial schedule and to allocate these three ancillary services. One of the models has crisp nature considering that voltage and branch flow limits are rigid while the second one admits that voltage and branch flow limits are modeled in a soft way using Fuzzy Set concepts. Finally, the paper illustrates the application of these models with a Case Study using a 55 node MV/LV network. (author)

  12. Substation Reactive Power Regulation Strategy

    Science.gov (United States)

    Zhang, Junfeng; Zhang, Chunwang; Ma, Daqing

    2018-01-01

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

  13. A study on electric power management for power producer-suppliers utilizing output of megawatt-solar power plants

    Directory of Open Access Journals (Sweden)

    Hirotaka Takano

    2016-01-01

    Full Text Available The growth in penetration of photovoltaic generation units (PVs has brought new power management ideas, which achieve more profitable operation, to Power Producer-Suppliers (PPSs. The expected profit for the PPSs will improve if they appropriately operate their controllable generators and sell the generated electricity to contracted customers and Power Exchanges together with the output of Megawatt-Solar Power Plants (MSPPs. Moreover, we can expect that the profitable cooperation between the PPSs and the MSPPs decreases difficulties in the supply-demand balancing operation for the main power grids. However, it is necessary that the PPSs treat the uncertainty in output prediction of PVs carefully. This is because there is a risk for them to pay a heavy imbalance penalty. This paper presents a problem framework and its solution to make the optimal power management plan for the PPSs in consideration with the electricity procurement from the MSPPs. The validity of the authors’ proposal is verified through numerical simulations and discussions of their results.

  14. Combining the Power of Wind and Water in Quebec

    Energy Technology Data Exchange (ETDEWEB)

    Richard, D.

    2007-07-01

    Wind varies and is impossible to store, major factors that have curbed and continue to curb the development of wind power. Hydroelectric generating stations with reservoirs, on the other hand, are quite capable of adjusting their output and can thus buffer fluctuations in consumption or in the output of other generating facilities on the grid. Combining wind power and hydropower thus involves using hydroelectric generating stations to offset the intermittent nature of wind power. The consumer, however, does not automatically reap the benefits of this complementarity. To achieve this, Quebec has implemented a 1,000-MW balancing agreement between the hydropower producer and the electricity distributor, which has signed wind power purchase agreements. The balancing agreement establishes two charges: one based on firming capacity provided by the producer and another linked to errors in the forecast of wind power generation that the distributor makes each day. This structure compensates the producer for the reduced margin of flexibility it has to engage in energy trading. (auth)

  15. Annual Energy Balance Sheets 2001-2002

    International Nuclear Information System (INIS)

    2004-01-01

    During the year 2002 the primary supply of energy reached 629 TWh, which is 7.7 TWh less than 2001. The decrease originates mainly from the reduced electricity production from water power. Also the electricity production in nuclear power plants decreased by 4.5 TWh. If we were to look at the supplied energy for final consumption we will find a slightly rise by 1.8 TWh. The year 2002 was warmer than a 'normal' year and that consequently brings lower energy needs. Compared with 2001, 2002 was not warmer and a net electricity import of 5.4 TWh covered the energy needs. The energy use increased by 3.3 TWh between 2002 and 2001. The industry sector shows the largest rise by 2.9 TWh, nearly 2 per cent. Within that sector, energy from biomass fuel had a rise by 6.7 per cent. The household sector decreases its energy use by 2.7 per cent, and oil and electricity show the largest decrease. The proportionately high electricity price probably had a slowing down effect on the electricity use. The balance sheets of energy sources are showing the total supply and consumption of energy sources expressed in original units, i.e. units recorded in the primary statistics - mainly commercial units. The production of derived energy commodities is recorded on the supply - side of the balance sheets of energy sources, which is not the case in the energy balance sheets. The balance sheets of energy sources also include specifications of input--output and energy consumption in energy conversion industries. The energy balance sheets are based on primary data recorded in the balance sheets of energy sources, here expressed in a common energy unit, TJ. The production of derived energy is recorded in a second flow-step comprising energy turnover in energy conversion and is also specified in complementary input - output tables for energy conversion industries. The following items are shown in the energy balance sheets. 1.1 Inland supply of primary energy; 1.3 Import; 1.4 Export; 1.5 Changes in

  16. Fluctuation and thermal energy balance for drift-wave turbulence

    International Nuclear Information System (INIS)

    Kim, Chang-Bae; Horton, W.

    1990-05-01

    Energy conservation for the drift-wave system is shown to be separated into the wave-energy power balance equation and an ambient thermal-energy transport equation containing the anomalous transport fluxes produced by the fluctuations. The wave energy equation relates the wave energy density and wave energy flux to the anomalous transport flux and the dissipation of the fluctuations. The thermal balance equation determines the evolution of the temperature profiles from the divergence of the anomalous heat flux, the collisional heating and cooling mechanisms and the toroidal pumping effect. 16 refs., 1 tab

  17. Fluctuation and thermal energy balance for drift-wave turbulence

    International Nuclear Information System (INIS)

    Changbae Kim; Horton, W.

    1991-01-01

    Energy conservation for the drift-wave system is shown to be separated into the wave-energy power balance equation and an ambient thermal-energy transport equation containing the anomalous transport fluxes produced by the fluctuations. The wave energy equation relates the wave energy density and wave energy flux to the anomalous transport flux and the dissipation of the fluctuations. The thermal balance equation determines the evolution of the temperature profiles from the divergence of the anomalous heat flux, the collisional heating and cooling mechanisms and the toroidal pumping effect. (author)

  18. Japan and India: soft balancing as a reaction to China's rise?

    Directory of Open Access Journals (Sweden)

    Wellington Amorim

    2014-01-01

    Full Text Available What are Indian and Japanese reactions to China's rise in economic, political and military terms? According to realist tradition, their option would be between balancing and bandwagoning. Applying Stephen Walt's balance of threats approach, this work aims to analyze Indian and Japan responses to an increasingly powerful China; its conclusions point to an evolving relationship between India and Japan, in military terms, especially after 2005.

  19. Thermal performance test for steam turbine of nuclear power plants

    International Nuclear Information System (INIS)

    Bu Yubing; Xu Zongfu; Wang Shiyong

    2014-01-01

    Through study of steam turbine thermal performance test of CPR1000 nuclear power plant, we solve the enthalpy calculation problems of the steam turbine in wet steam zone using heat balance method which can help to figure out the real overall heat balance diagram for the first time, and we develop a useful software for thermal heat balance calculation. Ling'ao phase II as an example, this paper includes test instrument layout, system isolation, risk control, data acquisition, wetness measurement, heat balance calculation, etc. (authors)

  20. Balancing power: A grounded theory study on partnership of academic service institutes

    Directory of Open Access Journals (Sweden)

    FATEMEH HESHMATI NABAVI

    2017-07-01

    Full Text Available Introduction: Governments and professional organizations have called for new partnerships between health care providers and academics to improve clinical education for the benefit of both students and patients. To develop a substantive grounded theory on the process of forming academic-service partnerships in implementing clinical education, from the perspective of academic and clinical nursing staff members and managers working in Iranian settings. Methods: The participants included 15 hospital nurses, nurse managers, nurse educators, and educational managers from two central universities and clinical settings from 2009 to 2012. Data were collected through 30 in-depth, semi-structure interviews with the individual participants and then analyzed using the methodology of Strauss and Corbin’s grounded theory. Results: Utilizing “balancing power” as the core variable enabled us to integrate the concepts concerning the partnership processes between clinical and educational institutes. Three distinct and significant categories emerged to explain the process of partnership: 1 divergence, 2 conflict between educational and caring functions, and 3 creation of balance between educational and caring functions. Conclusions: In implementing clinical education, partnerships have been formed within a challenging context in Iran. Conflict between clinical and educational functions was the main concern of both sides of the partnership in forming a collaborative relationship, with our findings emphasizing the importance of nursing educators’ role in the establishment of partnership programs.

  1. Spreadsheet eases heat balance, payback calculations

    International Nuclear Information System (INIS)

    Conner, K.P.

    1992-01-01

    This paper reports that a generalized Lotus type spreadsheet program has been developed to perform the heat balance and simple payback calculations for various turbine-generator (TG) inlet steam pressures. It can be used for potential plant expansions or new cogeneration installations. The program performs the basic heat balance calculations that are associated with turbine-generator, feedwater heating process steam requirements and desuperheating. The printout, shows the basic data and formulation used in the calculations. The turbine efficiency data used are applicable for automatic extraction turbine-generators in the 30-80 MW range. Simple payback calculations are for chemical recovery boilers and power boilers used in the pulp and paper industry. However, the program will also accommodate boilers common to other industries

  2. Evaluation of nodal reliability risk in a deregulated power system with photovoltaic power penetration

    DEFF Research Database (Denmark)

    Zhao, Qian; Wang, Peng; Goel, Lalit

    2014-01-01

    Owing to the intermittent characteristic of solar radiation, power system reliability may be affected with high photovoltaic (PV) power penetration. To reduce large variation of PV power, additional system balancing reserve would be needed. In deregulated power systems, deployment of reserves...... and customer reliability requirements are correlated with energy and reserve prices. Therefore a new method should be developed to evaluate the impacts of PV power on customer reliability and system reserve deployment in the new environment. In this study, a method based on the pseudo-sequential Monte Carlo...... simulation technique has been proposed to evaluate the reserve deployment and customers' nodal reliability with high PV power penetration. The proposed method can effectively model the chronological aspects and stochastic characteristics of PV power and system operation with high computation efficiency...

  3. Two-Dimension Sorting and Selection Algorithm featuring Thermal Balancing Control for Modular Multilevel Converters

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Máthé, Lászlo; Teodorescu, Remus

    2016-01-01

    With the aim to solve the unbalanced thermal behavior in the modular multilevel converter, introduced by mismatch in the submodule parameters, a thermal balancing control strategy is proposed here. The proposed solution ensures a balanced junction temperature for the power devices, while the bala...

  4. The effect of long-distance interconnection on wind power variability

    International Nuclear Information System (INIS)

    Fertig, Emily; Apt, Jay; Jaramillo, Paulina; Katzenstein, Warren

    2012-01-01

    We use time- and frequency-domain techniques to quantify the extent to which long-distance interconnection of wind plants in the United States would reduce the variability of wind power output. Previous work has shown that interconnection of just a few wind plants across moderate distances could greatly reduce the ratio of fast- to slow-ramping generators in the balancing portfolio. We find that interconnection of aggregate regional wind plants would not reduce this ratio further but would reduce variability at all frequencies examined. Further, interconnection of just a few wind plants reduces the average hourly change in power output, but interconnection across regions provides little further reduction. Interconnection also reduces the magnitude of low-probability step changes and doubles firm power output (capacity available at least 92% of the time) compared with a single region. First-order analysis indicates that balancing wind and providing firm power with local natural gas turbines would be more cost-effective than with transmission interconnection. For net load, increased wind capacity would require more balancing resources but in the same proportions by frequency as currently, justifying the practice of treating wind as negative load. (letter)

  5. Typical balance exercises or exergames for balance improvement?

    Science.gov (United States)

    Gioftsidou, Asimenia; Vernadakis, Nikolaos; Malliou, Paraskevi; Batzios, Stavros; Sofokleous, Polina; Antoniou, Panagiotis; Kouli, Olga; Tsapralis, Kyriakos; Godolias, George

    2013-01-01

    Balance training is an effective intervention to improve static postural sway and balance. The purpose of the present study was to investigate the effectiveness of the Nintendo Wii Fit Plus exercises for improving balance ability in healthy collegiate students in comparison with a typical balance training program. Forty students were randomly divided into two groups, a traditional (T group) and a Nintendo Wii group (W group) performed an 8 week balance program. The "W group" used the interactive games as a training method, while the "T group" used an exercise program with mini trampoline and inflatable discs (BOSU). Pre and Post-training participants completed balance assessments. Two-way repeated measures analyses of variance (ANOVAs) were conducted to determine the effect of training program. Analysis of the data illustrated that both training program groups demonstrated an improvement in Total, Anterior-posterior and Medial Lateral Stability Index scores for both limbs. Only at the test performed in the balance board with anterior-posterior motion, the improvement in balance ability was greater in the "T group" than the "W group", when the assessment was performed post-training (p=0.023). Findings support the effectiveness of using the Nintendo Wii gaming console as a balance training intervention tool.

  6. Battery Storage Systems as Grid-Balancing Measure in Low-Voltage Distribution Grids with Distributed Generation

    Directory of Open Access Journals (Sweden)

    Bernhard Faessler

    2017-12-01

    Full Text Available Due to the promoted integration of renewable sources, a further growth of strongly transient, distributed generation is expected. Thus, the existing electrical grid may reach its physical limits. To counteract this, and to fully exploit the viable potential of renewables, grid-balancing measures are crucial. In this work, battery storage systems are embedded in a grid simulation to evaluate their potential for grid balancing. The overall setup is based on a real, low-voltage distribution grid topology, real smart meter household load profiles, and real photovoltaics load data. An autonomous optimization routine, driven by a one-way communicated incentive, determines the prospective battery operation mode. Different battery positions and incentives are compared to evaluate their impact. The configurations incorporate a baseline simulation without storage, a single, central battery storage or multiple, distributed battery storages which together have the same power and capacity. The incentives address either market conditions, grid balancing, optimal photovoltaic utilization, load shifting, or self-consumption. Simulations show that grid-balancing incentives result in lowest peak-to-average power ratios, while maintaining negligible voltage changes in comparison to a reference case. Incentives reflecting market conditions for electricity generation, such as real-time pricing, negatively influence the power quality, especially with respect to the peak-to-average power ratio. A central, feed-in-tied storage performs better in terms of minimizing the voltage drop/rise and shows lower distribution losses, while distributed storages attached at nodes with electricity generation by photovoltaics achieve lower peak-to-average power ratios.

  7. A survey on wind power ramp forecasting.

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, C.; Gama, J.; Matias, L.; Botterud, A.; Wang, J. (Decision and Information Sciences); (INESC Porto)

    2011-02-23

    The increasing use of wind power as a source of electricity poses new challenges with regard to both power production and load balance in the electricity grid. This new source of energy is volatile and highly variable. The only way to integrate such power into the grid is to develop reliable and accurate wind power forecasting systems. Electricity generated from wind power can be highly variable at several different timescales: sub-hourly, hourly, daily, and seasonally. Wind energy, like other electricity sources, must be scheduled. Although wind power forecasting methods are used, the ability to predict wind plant output remains relatively low for short-term operation. Because instantaneous electrical generation and consumption must remain in balance to maintain grid stability, wind power's variability can present substantial challenges when large amounts of wind power are incorporated into a grid system. A critical issue is ramp events, which are sudden and large changes (increases or decreases) in wind power. This report presents an overview of current ramp definitions and state-of-the-art approaches in ramp event forecasting.

  8. Hidden in Plain Sight: Signs of Great Power War

    Science.gov (United States)

    2016-06-01

    China can change the strategic balance of power in the region without ever fighting—the acme of skill according to Sun Tzu . In fact, the balance of...68 BIBLIOGRAPHY ...put anyone into the shade, but we demand a place for ourselves in the sun .”20 This speech became the ideological foundation for Germany’s

  9. On the balance energy and nuclear dynamics in peripheral heavy-ion collisions

    International Nuclear Information System (INIS)

    Chugh, Rajiv; Puri, Rajeev K.

    2010-01-01

    We present here the system size dependence of balance energy for semi-central and peripheral collisions using quantum molecular dynamics model. For this study, the reactions of Ne 20 +Ne 20 , Ca 40 +Ca 40 , Ni 58 + Ni 58 , Nb 93 +Nb 93 , Xe 131 +Xe 131 , and Au 197 +Au 197 are simulated at different incident energies and impact parameters. A hard equation of state along with nucleon–nucleon cross-sections between 40 and 55 mb explains the data nicely. Interestingly, balance energy follows a power law ∝A τ for the mass dependence at all colliding geometries. The power factor τ is close to –1/3 in central collisions, whereas it is –2/3 for peripheral collisions suggesting stronger system size dependence at peripheral geometries. This also suggests that in the absence of momentum dependent interactions, Coulomb's interaction plays an exceedingly significant role. These results are further analyzed for nuclear dynamics at the balance point. (author)

  10. Utilization of Model Predictive Control to Balance Power Absorption Against Load Accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, Nikhar [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tom, Nathan M [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-06-03

    Wave energy converter (WEC) control strategies have been primarily focused on maximizing power absorption. The use of model predictive control strategies allows for a finite-horizon, multiterm objective function to be solved. This work utilizes a multiterm objective function to maximize power absorption while minimizing the structural loads on the WEC system. Furthermore, a Kalman filter and autoregressive model were used to estimate and forecast the wave exciting force and predict the future dynamics of the WEC. The WEC's power-take-off time-averaged power and structural loads under a perfect forecast assumption in irregular waves were compared against results obtained from the Kalman filter and autoregressive model to evaluate model predictive control performance.

  11. Study on process design of partially-balanced, hydraulically lifting vertical ship lift

    Science.gov (United States)

    Xin, Shen; Xiaofeng, Xu; Lu, Zhang; Bing, Zhu; Fei, Li

    2017-11-01

    The hub ship lift in Panjin is the first navigation structure in China for the link between the inland and open seas, which adopts a novel partially-balanced, hydraulically lifting ship lift; it can meet such requirements as fast and sharp water level change in open sea, large draft of a yacht, and launching of a ship reception chamber; its balancing weight system can effectively reduce the load of the primary lifting cylinder, and optimize the force distribution of the ship reception chamber. The paper provides an introduction to main equipment, basic principles, main features and system composition of a ship lift. The unique power system and balancing system of the completed ship lift has offered some experience for the construction of the tourism-type ship lifts with a lower lifting height.

  12. Balance Problems

    Science.gov (United States)

    ... fully trust your sense of balance. Loss of balance also raises the risk of falls. This is a serious and even life-threatening ... 65. Balance disorders are serious because of the risk of falls. But occasionally balance problems may warn of another health condition, such ...

  13. An energy balance concept for habitability.

    Science.gov (United States)

    Hoehler, Tori M

    2007-12-01

    Habitability can be formulated as a balance between the biological demand for energy and the corresponding potential for meeting that demand by transduction of energy from the environment into biological process. The biological demand for energy is manifest in two requirements, analogous to the voltage and power requirements of an electrical device, which must both be met if life is to be supported. These requirements exhibit discrete (non-zero) minima whose magnitude is set by the biochemistry in question, and they are increased in quantifiable fashion by (i) deviations from biochemically optimal physical and chemical conditions and (ii) energy-expending solutions to problems of resource limitation. The possible rate of energy transduction is constrained by (i) the availability of usable free energy sources in the environment, (ii) limitations on transport of those sources into the cell, (iii) upper limits on the rate at which energy can be stored, transported, and subsequently liberated by biochemical mechanisms (e.g., enzyme saturation effects), and (iv) upper limits imposed by an inability to use "power" and "voltage" at levels that cause material breakdown. A system is habitable when the realized rate of energy transduction equals or exceeds the biological demand for energy. For systems in which water availability is considered a key aspect of habitability (e.g., Mars), the energy balance construct imposes additional, quantitative constraints that may help to prioritize targets in search-for-life missions. Because the biological need for energy is universal, the energy balance construct also helps to constrain habitability in systems (e.g., those envisioned to use solvents other than water) for which little constraint currently exists.

  14. Start. Slovak power stations, Nuclear Power Plants Mochovce (Annual report 1998)

    International Nuclear Information System (INIS)

    1999-01-01

    A brief account of activities carried out by the Nuclear power plants Mochovce in 1998 is presented. These activities are reported under the headings: (1) Director's foreword; (2) Power plant management; (3) Highlights of 1998; (4) Quality system; (5) Electricity and heat generation; Maintenance; Capital construction; (6) Radiation safety; Environmental impacts of operations; (7) List of balances; Human resources; (8) International co-operation; Public relations

  15. Estimating the impacts of wind power on power systems—summary of IEA Wind collaboration

    Science.gov (United States)

    Holttinen, Hannele

    2008-04-01

    Adding wind power to power systems will have beneficial impacts by reducing the emissions of electricity production and reducing the operational costs of the power system as less fuel is consumed in conventional power plants. Wind power will also have a capacity value to a power system. However, possible negative impacts will have to be assessed to make sure that they will only offset a small part of the benefits and also to ensure the security of the power system operation. An international forum for the exchange of knowledge of power system impacts of wind power has been formed under the IEA Implementing Agreement on Wind Energy. The Task 'Design and Operation of Power Systems with Large Amounts of Wind Power' is analyzing existing case studies from different power systems. There are a multitude of studies completed and ongoing related to the cost of wind integration. However, the results are not easy to compare. This paper describes the general issues of wind power impacts on power systems and presents a comparison of results from ten case studies on increased balancing needs due to wind power.

  16. Estimating the impacts of wind power on power systems-summary of IEA Wind collaboration

    International Nuclear Information System (INIS)

    Holttinen, Hannele

    2008-01-01

    Adding wind power to power systems will have beneficial impacts by reducing the emissions of electricity production and reducing the operational costs of the power system as less fuel is consumed in conventional power plants. Wind power will also have a capacity value to a power system. However, possible negative impacts will have to be assessed to make sure that they will only offset a small part of the benefits and also to ensure the security of the power system operation. An international forum for the exchange of knowledge of power system impacts of wind power has been formed under the IEA Implementing Agreement on Wind Energy. The Task 'Design and Operation of Power Systems with Large Amounts of Wind Power' is analyzing existing case studies from different power systems. There are a multitude of studies completed and ongoing related to the cost of wind integration. However, the results are not easy to compare. This paper describes the general issues of wind power impacts on power systems and presents a comparison of results from ten case studies on increased balancing needs due to wind power

  17. Inherent reactor power controller for a metal-fueled ALMR

    International Nuclear Information System (INIS)

    Wood, R.T.; Wilson, T.L. Jr.

    1990-01-01

    Inherent power control for metal-fueled ALMR designs involves using reactivity thermal feedback effects to control reactor power. This paper describes how, using classical control design techniques, a control system for normal load following maneuvers was deigned for a pool-type ALMR. This design provides active control of power removal in the balance of plant, direct control of selected primary and intermediate loop temperatures, and passive control of reactor power. The inherent stability of the strong, fast reactivity feedback effects bring heat production in the core into balance with the heat removal system temperatures, which are controlled to meet power demand. A simulation of the control system successfully responded to a 10% step change in power demand by changing power at an acceptable rate without causing large temperature fluctuations or exceeding thermal limits

  18. Towards a Pan-European energy balancing market : exercise on coupling the United Kingdom and continental Europe

    NARCIS (Netherlands)

    Escudero Concha, C.; Haan, de J.E.S.; Virag, A.; Gibescu, M.; Kling, W.L.

    2014-01-01

    Increasing levels of wind power generation in the coming years will displace conventional generation, impacting the need for balancing reserves. The upcoming integration of pan-European balancing markets seeks to increase collaboration between areas for optimal provision of services. The challenge

  19. Propulsion element requirements using electrical power system unscheduled power

    Science.gov (United States)

    Zimmermann, Frank; Hodge, Kathy

    1989-01-01

    The suitability of using the electrical energy from the Space Station's Electrical Power System (EPS) during the periods of peak solar insolation which is currently not specifically allocated (unscheduled power) to produce propulsion propellants, gaseous hydrogen, and oxygen by electrolyzing water is investigated. Reboost propellant requirements are emphasized, but the results are more generally relevant because the balance of recurring propellant requirements are an order of magnitude smaller and the nonrecurring requirements are not significant on an average basis.

  20. 12. national conference of Czechoslovak power specialists

    International Nuclear Information System (INIS)

    1983-01-01

    The XIIth national conference of Czechoslovak power specialists was held in Bratislava from October 5 to 7, 1983. Of the total number of 32 papers 12 were incorporated in the INIS system, i.e., such which dealt with the development of the nuclear power complex and the rationalization of sources and the use of heat in the Czechoslovak energy balance. (E.S.)