WorldWideScience

Sample records for 3mw power level

  1. 2.3-MW Medium-Voltage, Three-Level Wind Energy Inverter Applying a Unique Bus Structure and 4.5-kV Si/SiC Hybrid Isolated Power Modules: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Erdman, W.; Keller, J.; Grider, D.; VanBrunt, E.

    2014-11-01

    A high-efficiency, 2.3-MW, medium-voltage, three-level inverter utilizing 4.5-kV Si/SiC (silicon carbide) hybrid modules for wind energy applications is discussed. The inverter addresses recent trends in siting the inverter within the base of multimegawatt turbine towers. A simplified split, three-layer laminated bus structure that maintains low parasitic inductances is introduced along with a low-voltage, high-current test method for determining these inductances. Feed-thru bushings, edge fill methods, and other design features of the laminated bus structure provide voltage isolation that is consistent with the 10.4-kV module isolation levels. Inverter efficiency improvement is a result of the (essential) elimination of the reverse recovery charge present in 4.5-kV Si PIN diodes, which can produce a significant reduction in diode turn-off losses as well as insulated-gate bipolar transistor (IGBT) turn-on losses. The hybrid modules are supplied in industry-standard 140 mm x 130 mm and 190 mm x 130 mm packages to demonstrate direct module substitution into existing inverter designs. A focus on laminated bus/capacitor-bank/module subassembly level switching performance is presented.

  2. Reliability Estimation with Uncertainties Consideration for High Power IGBTs in 2.3 MW Wind Turbine Converter System

    DEFF Research Database (Denmark)

    Kostandyan, Erik; Ma, Ke

    2012-01-01

    This paper investigates the lifetime of high power IGBTs (insulated gate bipolar transistors) used in large wind turbine applications. Since the IGBTs are critical components in a wind turbine power converter, it is of great importance to assess their reliability in the design phase of the turbin...

  3. Energy Storage System by Means of Improved Thermal Performance of a 3 MW Grid Side Wind Power Converter

    DEFF Research Database (Denmark)

    Qin, Zian; Liserre, Marco; Blaabjerg, Frede;

    2013-01-01

    method of the energy storage system. Then the conventional thermal evaluation approach is simplified for evaluation with long term wind profile. The case studies are done to address the optimal power size and capacity of the energy storage system by comparing the improvement of the thermal performance...

  4. A new Main Injector radio frequency system for 2.3 MW Project X operations

    CERN Document Server

    Dey, J

    2012-01-01

    For Project X Fermilab Main Injector will be required to provide up to 2.3 MW to a neutrino production target at energies between 60 and 120 GeV. To accomplish the above power levels 3 times the current beam intensity will need to be accelerated. In addition the injection energy of Main Injector will need to be as low as 6 GeV. The current 30 year old Main Injector radio frequency system will not be able to provide the required power and a new system will be required. The specifications of the new system will be described.

  5. Research and development of a 3 MW power plant from the design, development, and demonstration of a 100 KW power system utilizing the direct contact heat exchanger concept for geothermal brine recovery project

    Science.gov (United States)

    Huebner, A. W.; Wall, D. A.; Herlacher, T. L.

    1980-09-01

    The design phase for the 100 KW unit consumed the months of May through November 1978, with the final design having a direct contact boiler and condenser, a single-stage radial inflow induction turbine generator using isopentane as the working fluid, and a single cell ejector-type cooling tower. The unit was constructed on two, forty-foot flatbed trailers between the months of October 1978 and June 1979. Systems start-up testing, in-field modifications, unit operation, and performance testing were performed between July and December 1979. AP and L (Arkansas Power and Light) personnel assumed responsibility of the unit at that time and conducted further maintenance, operations, and testing through August 1980.

  6. Characteristics and facilities of a 3MW LEU fuelled TRIGA reactor

    International Nuclear Information System (INIS)

    A 3 MW TRIGA reactor fuelled with low enriched uranium having 19.7 % U-235 and 20 wt% Uranium and Zirconium Hydride, has been installed and recently made critical at a research laboratory of the Bangladesh Atomic Energy Commission. This paper describes the basic design, low and high power test results and the facilities of the reactor. The details of the core configuration of the initial criticality with 50 elements and the final core with 100 elements at 3 MW power are discussed. The available experimental facilities are also described briefly. (author)

  7. Thermal Hydraulics Analysis for the 3MW TRIGA MARK-II Research Reactor Under Transient Condition

    International Nuclear Information System (INIS)

    Some important thermal hydraulic parameters of the 3 MW TRIGA MARK-II research reactor operating under transient condition were investigated using two computer codes PULTRI and TEMPUL. Major transient parameters, such as, peak power and prompt energy released after pulse, maximum fuel and coolant temperature, surface heat flux, time and radial distribution of temperature within fuel element after pulse, fuel, fuel-cladding gap width variation, etc. were computer and compared with the experimental and operational values as reported in the safety Analysis Report (SAR). It was observed that pulsing of the reactor inserting an excess reactivity of $2.00 shoots the reactor power level to 854.353 MW compared to an experimental value of 852 MW; the maximum fuel temperature corresponding to this peak power was found to be 846.76o C which is much less than the limiting maximum value of fuel temperature of 11500 C as reported in SAR. During a pulse if the film boiling occurs for a peak adiabatic fuel temperature of 1000o C, the calculated outer cladding wall temperature was observed to be 702.390 C compared to a value of 760o C reported in SAR under the same condition. The investigated other results were also found to be in good agreement with the values reported in the SAR. 16 refs., 22 figs. (author)

  8. Spent Fuel Management Program in the 3MW TRIGA MARK-II Research Reactor of Bangladesh

    International Nuclear Information System (INIS)

    Bangladesh Atomic Energy Commission (BAEC) has been operating a 3 MW TRIGA MARK II research reactor since 1986. The reactor was installed in the campus of the Atomic Energy Research Establishment (AERE) at Savar, Dhaka. It is one of the main nuclear research facilities in the country. The reactor uses TRIGA LEU fuel with uranium content of 20% by weight. The enrichment level of the fuel is 19.7%. The reactor has so far been operated for 7834 hours with a total cumulative burn up of 15898 MWh (662.5 MWd). The total burn up life of the present core is 1200 MWd. The main areas of use are: training of man-power for nuclear power plant applications, radioisotope (RI) production, neutron activation analysis (NAA), neutron radiography (NR) and neutron scattering. The government of Bangladesh has taken decision to establish nuclear power programme in the country. There is an ADP (Annual Development Project) to accomplish necessary activities for construction of medium size nuclear power plant (NPP) in the western zone of the country. Now, with regard to the safe management, storage of spent fuel and disposal of radioactive waste arising from operation of the research reactor and also from the proposed NPP expected to be constructed in future, BAEC is drawing up short and long-term plans and programs. At present, there does not exist any spent fuel element in the reactor facility. It is to be mentioned that Bangladesh is aware of the US DOE’s ‘Take Back Program’ in connection with the research reactor spent fuel of US origin, and is very much interested to take part in this program. The paper presents the current status of handling and storage facilities available for spent fuel and strategy for the safe management of spent fuel to be generated from the research reactor in near future. (author)

  9. Plan for the safe decommissioning of the BAEC 3MW TRIGA MARK-II research reactor

    International Nuclear Information System (INIS)

    The 3 MW TRIGA Mark-II research reactor of Bangladesh Atomic Energy Commission (BAEC) has been operating since September 14, 1986. The reactor is used for radioisotope production (131I, 99mTc, 46Sc), various R and D activities, and manpower training. The reactor has been operated successfully since it's commissioning with the exception of a few reportable incidents. Of these, the decay tank leakage incident of 1997 is considered to be the most significant one. As a result of this incident, reactor operation at full power remained suspended for about 4 years. However, the reactor operation was continued during this period at a power level of 250 kW to cater the needs of various R and D groups, which required lower neutron flux for their experiments. This was made possible by establishing a temporary by pass connection across the decay tank using local technology. The reactor was made operational again at full power after successful replacement of the damaged decay tank in August 2001. At present the reactor is operated 5 days a week at a full power level of 3 MW for production of I-131 and R and D purposes. Up to December 2005 total burn-up of the core stands at about 358 Megawatt Days (MWDs). BAEC has planned to increase the production of 131I and as such, the core burn-up is expected to be increased very significantly in the years to come. There is a declaration from the US DOE that all US origin research reactor spent fuel generated within 2006 will be taken away to the USA at their own cost within 2009. But the fuel burn up of the BAEC research reactor is about 6%. So the reactor can operate for about 10-20 years more. An initial decommissioning plan for the BAEC TRIGA reactor and relevant facilities should be established as early as possible as recommended in the IAEA Safety Standards Series No.WS-G-2.1 (Decommissioning of Nuclear Power Plants and Research Reactors - Safety Standards Series No.WS-G-2.1, IAEA, Vienna, 1999). During the design and construction

  10. The 3 MW ECRH/ECCD transmission and launching system on TORE SUPRA

    International Nuclear Information System (INIS)

    The ECRH experiment on TORE SUPRA is designed to inject up to 3 MW of power at 118 GHz using an antenna consisting of six fixed spherical mirrors and three mobile steering mirrors. The position of the mobile mirrors can be varied in real time using two stepper motors for each mobile mirror. In addition to controlling the injection angle, the position of the mobile mirrors also affects the polarisation of the injected wave. Accurate formulae to compute, in real time, the stepper motor positions required to obtain the desired beam injection angles have been derived. Formulae to determine the effect on the wave polarisation, of the actual mobile mirror positions have also been determined. These formulae have been verified by precise laser measurements and by comparison of power deposition calculations and experimental results. (authors)

  11. The DIII-D 3 MW, 110 GHz ECH system

    Science.gov (United States)

    Callis, R. W.; Lohr, J.; Ponce, D.; O'Neill, R. C.; Prater, R.; Luce, T. C.

    1999-09-01

    Three 110 GHz gyrotrons with nominal output power of 1 MW each have been installed and are operational on the DIII-D tokamak. One gyrotron is built by Gycom and has a nominal rating of 1 MW and a 2 s pulse length, with the pulse length being determined by the maximum temperature allowed on the edge cooled Boron Nitride window. The second and third gyrotrons were built by Communications and Power Industries (CPI). The first CPI gyrotron uses a double disc FC-75 cooled sapphire window which has a pulse length rating of 0.8 s at 1 MW, 2 s at 0.5 MW and 10 s at 0.35 MW. The second CPI gyrotron, utilizes a single disc chemical-vapor-deposition diamond window, that employs water cooling around the edge of the disc. Calculation predict that the diamond window should be capable of full 1 MW cw operation. All gyrotrons are connected to the tokamak by a low-loss-windowless evacuated transmission line using circular corrugated waveguide for propagation in the HE11 mode. Each waveguide system incorporates a two mirror launcher which can steer the rf beam poloidally from the center to the outer edge of the plasma. Central current drive experiments with the two gyrotrons with 1.5 MW of injected power drove about 0.17 MA. Results from using the three gyrotron systems will be reported as well as the plans to upgrade the system to 6 MW.

  12. Status of spent fuel in the 3MW BAEC MK-II research reactor facility of Bangladesh

    International Nuclear Information System (INIS)

    Bangladesh has been operating a 3 MW TRIGA MARK II research reactor since 1986. The reactor is installed in the campus of the Atomic Energy Research Establishment (AERE) at Savar, which is located about 40 km northwest of Dhaka. It is one of the main nuclear research facilities in the country. The reactor uses TRIGA LEU fuel with uranium content of 20% by weight. The enrichment level of the fuel is 19.7%. So far the reactor has been operated for 5624 hours with a total cumulative burnup (BU) of 10 690 MWh (445 MWd). The main areas of use are: training of man-power for research reactor operation and applications, radioisotope (RI) production, neutron activation analysis (NAA), neutron radiography (NR) and neutron scattering. Radioisotopes produced to date are: I-131, Sc-46 and Tc-99m. Bangladesh is a peace loving country with a strong commitment towards nuclear nonproliferation. Accordingly, it has signed several multilateral and bilateral agreements, protocols, treaties, etc. prevailing in the International Nuclear Non-proliferation regime. Bangladesh has also signed a Nuclear Cooperation Agreement with the USA on 17 September 1981, which facilitated export of nuclear technology from the USA to Bangladesh. The research reactor was procured under the provisions of this agreement. In 2003, the tenure of the Agreement was extended up to 2012. At present, there does not exist any spent fuel element in the reactor facility. However, with the recently undertaken RI production enhancement program, it is expected that the reactor will start generating spent fuels from the year 2012. It is to be mentioned that Bangladesh is aware of the US DOE's 'Take Back Program' in connection with the research reactor spent fuel of US origin, and is very much interested to take part in this program. The paper presents the current status of handling and storage facilities available for spent fuel and strategy for the safe management spent fuel to be generated from the research reactor in

  13. Characterization of blade throw from a 2.3MW horizontal axis wind turbine upon failure

    DEFF Research Database (Denmark)

    Sarlak, Hamid; Sørensen, Jens Nørkær

    2015-01-01

    The present work concerns aerodynamics of thrown objects from a 2.3 MW Horizontal Axis Wind Turbine (HAWT), as a consequence of blade failure. The governing set of ordinary differential equations for the flying objects are derived and numerically solved using a 4th order Runge-Kutta time advancin...

  14. Race-track coils for a 3 MW HTS ship motor

    International Nuclear Information System (INIS)

    Highlights: • Sumitomo Electric manufactured the HTS field coils for a 3 MW HTS ship motor. • The motor was developed and successfully passed the loading test by Kawasaki Heavy. • We tested and obtained the basic data to evaluate the 20-year durability of coils. - Abstract: Since the discovery of high-temperature superconductivity (HTS), Sumitomo Electric has been developing silver-sheathed Bi2223 superconducting wire and products. Ship propulsion motors are one of the most promising applications of HTS. Sumitomo Electric Industries, Ltd. (SEI) has recently manufactured 24 large racetrack coils, using 70 km long DI-BSCCO wires, for use in a 3 MW HTS motor developed by Kawasaki Heavy Industries, Ltd. (KHI). The 3 MW HTS motor, using our newly developed racetrack coils, has successfully passed the loading test. It is particularly important that the HTS field coils used in ship propulsion motors can withstand the expansive forces repeatedly applied to them. As racetrack type coils have straight sections, the support mechanism they require to withstand expansive forces is very different from that of circular coils. Therefore, we ran tests and obtained the basic data to evaluate the 20-year durability of racetrack coils against the repeatedly applied expansive forces expected in domestic ship propulsion motors

  15. Race-track coils for a 3 MW HTS ship motor

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, E., E-mail: ueno-eisaku@sei.co.jp; Kato, T.; Hayashi, K.

    2014-09-15

    Highlights: • Sumitomo Electric manufactured the HTS field coils for a 3 MW HTS ship motor. • The motor was developed and successfully passed the loading test by Kawasaki Heavy. • We tested and obtained the basic data to evaluate the 20-year durability of coils. - Abstract: Since the discovery of high-temperature superconductivity (HTS), Sumitomo Electric has been developing silver-sheathed Bi2223 superconducting wire and products. Ship propulsion motors are one of the most promising applications of HTS. Sumitomo Electric Industries, Ltd. (SEI) has recently manufactured 24 large racetrack coils, using 70 km long DI-BSCCO wires, for use in a 3 MW HTS motor developed by Kawasaki Heavy Industries, Ltd. (KHI). The 3 MW HTS motor, using our newly developed racetrack coils, has successfully passed the loading test. It is particularly important that the HTS field coils used in ship propulsion motors can withstand the expansive forces repeatedly applied to them. As racetrack type coils have straight sections, the support mechanism they require to withstand expansive forces is very different from that of circular coils. Therefore, we ran tests and obtained the basic data to evaluate the 20-year durability of racetrack coils against the repeatedly applied expansive forces expected in domestic ship propulsion motors.

  16. Thermal-Hydraulic Analysis of the 3-MW TRIGA MARK-II Research Reactor Under Steady-State and Transient Conditions

    International Nuclear Information System (INIS)

    Important thermal-hydraulic parameters of the 3-MW TRIGA MARK-II research reactor operating under both steady-state and transient conditions are reported. Neutronic analyses were performed by using the CITATION diffusion code and the MCNP4B2 Monte Carlo code. The output of CITATION and MCNP4B2 were input to the PARET thermal-hydraulic code to study the steady-state and transient thermal-hydraulic behavior of the reactor. To benchmark the PARET model, data were obtained from different measurements performed by thermocouples in the instrumented fuel (IF) rod during the steady-state operation both under forced- and natural-convection mode and compared with the calculation. The mass flow rates needed for input to PARET were taken from the Final Safety Analysis Report for a downward forced coolant flow equivalent to 3500 gal/min. For natural convection cooling of the reactor, the mass flow rate was generated using the NCTRIGA code. Peak fuel temperatures measured by the thermocouples in the IF rods at different power levels of the TRIGA core were compared with the values calculated by PARET. The axial distribution of the temperatures of the fuel centerline, fuel surface, and the cladding surface in the hot channel were calculated for the reactor operating at the full-power level. Fuel surface heat flux and heat transfer coefficients for the hot channel were also calculated for the reactor operating at the full-power level. The investigated results were found to be in good agreement with the experimental and operational values. The testing of the PARET model calculations through benchmarking the available TRIGA experimental and operational data for pulse-mode operations showed that PARET can successfully be used to analyze the transient behavior of the reactor. Major transient parameters, such as peak power and prompt energy released after pulse, full-width at half-maximum of pulse peak, and maximum fuel centerline temperatures for different fuel elements at different

  17. Criticality and safety parameter studies for upgrading 3 MW TRIGA MARK II research reactor and validation of generated cross section library and computational method

    International Nuclear Information System (INIS)

    This study deals with the neutronic and thermal hydraulic analysis of the 3MW TRIGA MARK II research reactor to upgrade it to a higher flux. The upgrading will need a major reshuffling and reconfiguration of the current core. To reshuffle the current core configuration, the chain of NJOY94.10 - WIMSD-5A - CITATION - PARET - MCNP4B2 codes has been used for the overall analysis. The computational methods, tools and techniques, customisation of cross section libraries, various models for cells and super cells, and a lot of associated utilities have been standardised and established/validated for the overall core analysis. Analyses using the 4-group and 7-group libraries of macroscopic cross sections generated from the 69-group WIMSD-5 library showed that a 7-group structure is more suitable for TRIGA calculations considering its LEU fuel composition. The MCNP calculations established that the CITATION calculations and the generated cross section library are reasonably good for neutronic analysis of TRIGA reactors. Results obtained from PARET demonstrated that the flux upgrade will not cause the temperature limit on the fuel to be exceeded. Also, the maximum power density remains, by a substantial margin below the level at which the departure from nucleate boiling could occur. A possible core with two additional irradiation channels around the CT is projected where almost identical thermal fluxes as in the CT are obtained. The reconfigured core also shows 7.25% thermal flux increase in the Lazy Susan. (author)

  18. Index and reference levels for Power Quality

    International Nuclear Information System (INIS)

    The JWG C4.07 CIGRE/CIRED have the goal in quantification of index and reference levels of general character for being able to carry out analysis of Power Quality in the actual scenario of market liberalization

  19. Model Predictive Wind Turbine Control with Move-Blocking Strategy for Load Alleviation and Power Leveling

    Science.gov (United States)

    Jassmann, U.; Dickler, S.; Zierath, J.; Hakenberg, M.; Abel, D.

    2016-09-01

    This contribution presents a Model Predictive Controller (MPC) with moveblocking strategy for combined power leveling and load alleviation in wind turbine operation with a focus on extreme loads. The controller is designed for a 3 MW wind turbine developed by W2E Wind to Energy GmbH and compared to a baseline controller, using a classic control scheme, which currently operates the wind turbine. All simulations are carried out with a detailed multibody simulation turbine model implemented in alaska/Wind. The performance of the two different controllers is compared using a 50-year Extreme Operation Gust event, since it is one of the main design drivers for the wind turbine considered in this work. The implemented MPC is able to level electrical output power and reduce mechanical loads at the same time. Without de-rating the achieved control results, a move-blocking strategy is utilized and allowed to reduce the computational burden of the MPC by more than 50% compared to a baseline MPC implementation. This even allows to run the MPC on a state of the art Programmable Logic Controller.

  20. 3 MW TRIGA Research Reactor facility of BAEC and its Utilization

    Energy Technology Data Exchange (ETDEWEB)

    Molla, N.I.; Bhuiyan, S.I.; Wadud Mondal, M.A.; Ahmed, F.U.; Islam, M.N.; Hossain, S.M.; Ahmed, K.; Zulquarnain, A.; Abedin, Z. [Bangladesh Atomic Energy Commission, Atomic Energy Research Establishment, Dhaka (Bangladesh)

    1999-08-01

    The paper briefly describes the Utilisation of 3 MW TRIGA Research Reactor of BAEC for neutron beam research, neutron activation analysis are isotope production. It includes the installation of the triple axis neutron spectrometer at the radial piercing beam port and a neutron radiography set-up at the tangential beam port and their uses for material analysis and condensed matter research and material testing. Nuclear and magnetic structures of some ferrites have been studied in powder diffraction method in the double axis mode. SANS technique with double crystal diffraction known as Bonse and Hart's method has been adopted in an experiment with alumina sample. The neutron radiography set-up and its use in the detection of corrosion in alumina have been reported. Determination of arsenic concentration in drinking water from tube well via Instrumental Neutron Activation Analysis and production of radioiodine-131 by dry distillation method are presented. Our experience on the removal of N-16 decay tank because of the leakage of coolant and bringing the research reactor back to operational by-passing the decay tank have been focussed. A possible reconfiguration of the existing TRIGA core, without exceeding the safety margins, providing additional irradiation channel and upgrading the neutron flux for increased radioisotope production has been attempted. Cross section library ENDF/B-VI and JENDL3.2, code NJOY94.10, WIMSD package, 3-D code CITATION, PARET and Monte Carlo code MCNP4B2 have been employed to achieve the objective. (author)

  1. Neutronic Analysis of the 3 MW TRIGA MARK II Research Reactor, Part I: Monte Carlo Simulation

    International Nuclear Information System (INIS)

    This study deals with the neutronic analysis of the current core configuration of a 3 MW TRIGA MARK II research reactor at Atomic Energy Research Establishment (AERE), Savar, Dhaka, Bangladesh and validation of the results by benchmarking with the experimental, operational and available Final Safety Analysis Report (FSAR) values. The three-dimensional continuous-energy Monte Carlo code MCNP4C was used to develop a versatile and accurate full-core model of the TRIGA core. The model represents in detail all components of the core with literally no physical approximation. All fresh fuel and control elements as well as the vicinity of the core were precisely described. Continuous energy cross-section data from ENDF/B-VI and S(α, β) scattering functions from the ENDF/B-V library were used. The validation of the model against benchmark experimental results is presented. The MCNP predictions and the experimentally determined values are found to be in very good agreement, which indicates that the Monte Carlo model is correctly simulating the TRIGA reactor. (author)

  2. 3 MW TRIGA Research Reactor facility of BAEC and its Utilization

    International Nuclear Information System (INIS)

    The paper briefly describes the Utilisation of 3 MW TRIGA Research Reactor of BAEC for neutron beam research, neutron activation analysis are isotope production. It includes the installation of the triple axis neutron spectrometer at the radial piercing beam port and a neutron radiography set-up at the tangential beam port and their uses for material analysis and condensed matter research and material testing. Nuclear and magnetic structures of some ferrites have been studied in powder diffraction method in the double axis mode. SANS technique with double crystal diffraction known as Bonse and Hart's method has been adopted in an experiment with alumina sample. The neutron radiography set-up and its use in the detection of corrosion in alumina have been reported. Determination of arsenic concentration in drinking water from tube well via Instrumental Neutron Activation Analysis and production of radioiodine-131 by dry distillation method are presented. Our experience on the removal of N-16 decay tank because of the leakage of coolant and bringing the research reactor back to operational by-passing the decay tank have been focussed. A possible reconfiguration of the existing TRIGA core, without exceeding the safety margins, providing additional irradiation channel and upgrading the neutron flux for increased radioisotope production has been attempted. Cross section library ENDF/B-VI and JENDL3.2, code NJOY94.10, WIMSD package, 3-D code CITATION, PARET and Monte Carlo code MCNP4B2 have been employed to achieve the objective. (author)

  3. Low Power Design with High-Level Power Estimation and Power-Aware Synthesis

    CERN Document Server

    Ahuja, Sumit; Shukla, Sandeep Kumar

    2012-01-01

    Low-power ASIC/FPGA based designs are important due to the need for extended battery life, reduced form factor, and lower packaging and cooling costs for electronic devices. These products require fast turnaround time because of the increasing demand for handheld electronic devices such as cell-phones, PDAs and high performance machines for data centers. To achieve short time to market, design flows must facilitate a much shortened time-to-product requirement. High-level modeling, architectural exploration and direct synthesis of design from high level description enable this design process. This book presents novel research techniques, algorithms,methodologies and experimental results for high level power estimation and power aware high-level synthesis. Readers will learn to apply such techniques to enable design flows resulting in shorter time to market and successful low power ASIC/FPGA design. Integrates power estimation and reduction for high level synthesis, with low-power, high-level design; Shows spec...

  4. Thermal hydraulic transient study of 3 MW TRIGA Mark-II research reactor of Bangladesh using the EUREKA-2/RR code

    International Nuclear Information System (INIS)

    Highlights: ► Reactor power transition time depends on magnitude and form of reactivity. ► This time also depends on existing reactor power during reactivity insertion. ► Pattern of power transition depends on form of reactivity insertion. ► Doppler’s effect is seen for lower reactivity insertion when reactor power is low. ► EUREKA-2/RR code performs well for RIA and LOFA of TRIGA Mark-II research reactor. - Abstract: EUREKA-2/RR code has been used for the analyses of reactivity insertion accident (RIA) and loss of flow accident (LOFA) of 3 MW TRIGA Mark-II research reactor of Bangladesh. Transient characteristics of different parameters such as core power, fuel temperature, clad temperature, departure from nucleate boiling ratio (DNBR) due to the different form and magnitude of reactivity insertion has been focused. It is found from the analysis that the magnitude of insertion reactivity and the reactor operating power during this insertion impose a total effect on the core safety. Also, transient effects on reactor were studied for 15% loss of flow of the primary coolant. Provided the scram system is available, the reactor is found to shutdown safely in both cases. From these two studies in series, it is seen that EUREKA-2/RR is well suited for the analyses of reactor safety parameters with good approximations.

  5. Criticality and safety parameter studies for upgrading 3MW TRIGA MARK II research reactor and validation of generated cross section library and computational method

    International Nuclear Information System (INIS)

    The neutronic and thermal hydraulic analysis of the 3 MW TRIGA MARK II research reactor to upgrade it is presented. The upgrading will need a major reshuffling and reconfiguration of the current core. To realize this objective, the overall strategy followed is: 1.) generation of problem dependent cross section library from basic Evaluated Nuclear Data Files such as ENDF/B-VI, JENDL3.2 with NJOY94.10+, 2.) use WIMSD-5 package to generate cell constants for all of the materials in the core and its immediate neighborhood, 3.) use CITATION to perform 3-D global analysis of the core to study multiplication factor, neutron flux and power distributions, power peaking factors, temperature reactivity coefficients, etc., 4.) couple output of CITATION with PARET to study thermal hydraulic behavior to predict safety margins, 5.) check the validity of the deterministic codes with the Monte Carlo code MCNP4B2 , and 6.) reshuffle the current core configuration to achieve the desired objectives. The computational methods, tools and techniques, customization of cross section libraries, various models for cells and super cells, and a lot of associated utilities have been standardized and established/validated for the overall core analysis

  6. Power Analysis in Two-Level Unbalanced Designs

    Science.gov (United States)

    Konstantopoulos, Spyros

    2010-01-01

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

  7. Rotational Augmentation on a 2.3 MW Rotor Blade with Thick Flatback Airfoil Cross-Sections: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Schreck, S.; Fingersh, L.; Siegel, K.; Singh, M.; Medina, P.

    2013-01-01

    Rotational augmentation was analyzed for a 2.3 MW wind turbine, which was equipped with thick flatback airfoils at inboard radial locations and extensively instrumented for acquisition of time varying surface pressures. Mean aerodynamic force and surface pressure data were extracted from an extensive field test database, subject to stringent criteria for wind inflow and turbine operating conditions. Analyses of these data showed pronounced amplification of aerodynamic forces and significant enhancements to surface pressures in response to rotational influences, relative to two-dimensional, stationary conditions. Rotational augmentation occurrence and intensity in the current effort was found to be consistent with that observed in previous research. Notably, elevated airfoil thickness and flatback design did not impede rotational augmentation.

  8. Experimental Study of a Multi Level Overtopping Wave Power Device

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Hald, Tue; Frigaard, Peter Bak

    2002-01-01

    Results of experimental investigations of a floating wave energy device called Power Pyramid is presented. The Power Pyramid utilizes reservoirs in multiple levels when capturing wave overtopping and converting it into electrical energy. The effect of capturing the overtopping in multiple levels...

  9. Application of plasma attenuator for microwave power level control

    Directory of Open Access Journals (Sweden)

    V. L. Kofanov

    1967-12-01

    Full Text Available Correlations for the calculation of the circuit back coupling time constant of control power level system using filter which removes signal parasitic amplitude modulation are derived. System is described in which coefficient of the stabilization 250—300 is obtained when changing the input power level is 15—25 db.

  10. Challenges with Tertiary-Level Mechatronic Fluid Power

    DEFF Research Database (Denmark)

    Dransfield, Peter; Conrad, Finn

    1996-01-01

    As authors we take the view that mechatronics, as it relates to fluid power, has three levels which we designate as primary, secondary and tertiary. A brief review of the current status of fluid power, hydraulic and pneumatic, and of electronic control of it is presented and discussed. The focus...... is then on tertiary-level mechatronic fluid power and the challenges to it being applied successfully....

  11. Reactive Power Impact on Lifetime Prediction of Two-level Wind Power Converter

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede; Lau, M.;

    2013-01-01

    The influence of reactive power injection on the dominating two-level wind power converter is investigated and compared in terms of power loss and thermal behavior. Then the lifetime of both the partial-scale and full-scale power converter is estimated based on the widely used Coffin-Manson model....... It is concluded that the injection of the reactive power could have serious impact on the power loss and thermal profile, especially at lower wind speed. Furthermore, the introduction of the reactive power could also shorten the lifetime of the wind power converter significantly....

  12. Computational Analysis of Nuclear Safety Parameters of 3 MW TRIGA Mark-II Research Reactor Based on Evaluated Nuclear Data Libraries JENDL-3.3 and ENDF/B-VII.0

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Jahirul Haque [Bangladesh Atomic Energy Commission, Dhaka (Bangladesh)

    2013-07-01

    The objective of this study is to explain the main nuclear safety parameters of 3 MW TRIGA Mark-II Research Reactor at AERE, Savar, Dhaka, Bangladesh from the viewpoint of reactor safety and also reactor operator. The most important nuclear reactor physics safety parameters are power distribution, power peaking factors, shutdown margin, control rod worth, excess reactivity and fuel temperature reactivity coefficient. These parameters are calculated using the chain of the computer codes the SRAC-PIJ for cell calculation based on neutron transport theory and the SRAC-CITATION for core calculation based on neutron diffusion equation. To achieve this objective the TRIGA model is developed by the 3-D diffusion code SRAC-CITATION based on the group constants that come from the collision probability transport code SRAC-PIJ. In this study the evaluated nuclear data libraries JENDL-3.3 and ENDF/B-VII.0 are used. The calculated most important reactor physics parameters are compared to the safety analysis report (SAR) values as well as earlier published MCNP results (numerically benchmark). It was found that the calculated results show a good agreement between the said libraries. Besides, in most cases the calculated results reveal a reasonable agreement with the SAR values (by General Atomic) as well as the MCNP results. In addition, this analysis can be used as the inputs for thermal-hydraulic calculations of the TRIGA fresh core in the steady state and pulse mode operation. Because of power peaking factors, power distributions and temperature reactivity coefficients are the most important reactor safety parameters for normal operation and transient safety analysis in research as well as in power reactors. They form the basis for technical specifications and limitations for reactor operation such as loading pattern limitations for pulse operation (in TRIGA). Therefore, this analysis will be very important to develop the nuclear safety parameters data of 3 MW TRIGA Mark

  13. Computational Analysis of Nuclear Safety Parameters of 3 MW TRIGA Mark-II Research Reactor Based on Evaluated Nuclear Data Libraries JENDL-3.3 and ENDF/B-VII.0

    International Nuclear Information System (INIS)

    The objective of this study is to explain the main nuclear safety parameters of 3 MW TRIGA Mark-II Research Reactor at AERE, Savar, Dhaka, Bangladesh from the viewpoint of reactor safety and also reactor operator. The most important nuclear reactor physics safety parameters are power distribution, power peaking factors, shutdown margin, control rod worth, excess reactivity and fuel temperature reactivity coefficient. These parameters are calculated using the chain of the computer codes the SRAC-PIJ for cell calculation based on neutron transport theory and the SRAC-CITATION for core calculation based on neutron diffusion equation. To achieve this objective the TRIGA model is developed by the 3-D diffusion code SRAC-CITATION based on the group constants that come from the collision probability transport code SRAC-PIJ. In this study the evaluated nuclear data libraries JENDL-3.3 and ENDF/B-VII.0 are used. The calculated most important reactor physics parameters are compared to the safety analysis report (SAR) values as well as earlier published MCNP results (numerically benchmark). It was found that the calculated results show a good agreement between the said libraries. Besides, in most cases the calculated results reveal a reasonable agreement with the SAR values (by General Atomic) as well as the MCNP results. In addition, this analysis can be used as the inputs for thermal-hydraulic calculations of the TRIGA fresh core in the steady state and pulse mode operation. Because of power peaking factors, power distributions and temperature reactivity coefficients are the most important reactor safety parameters for normal operation and transient safety analysis in research as well as in power reactors. They form the basis for technical specifications and limitations for reactor operation such as loading pattern limitations for pulse operation (in TRIGA). Therefore, this analysis will be very important to develop the nuclear safety parameters data of 3 MW TRIGA Mark

  14. Battery Energy Storage System for PV Output Power Leveling

    OpenAIRE

    Rajkiran Singh; Seyedfoad Taghizadeh; Nadia Mei Lin Tan; Jagadeesh Pasupuleti

    2014-01-01

    Fluctuating photovoltaic (PV) output power reduces the reliability in power system when there is a massive penetration of PV generators. Energy storage systems that are connected to the PV generators using bidirectional isolated dc-dc converter can be utilized for compensating the fluctuating PV power. This paper presents a grid connected energy storage system based on a 2 kW full-bridge bidirectional isolated dc-dc converter and a PWM converter for PV output power leveling. This paper propos...

  15. Use of existing standards to measure sound power levels of powered hand tools-necessary revisions

    Science.gov (United States)

    Hayden, Charles S.; Zechmann, Edward

    2005-09-01

    At recent NOISE-CON and Acoustical Society of America meetings, noise rating labeling was discussed as a way of manufacturers providing full disclosure information for their noise emitting products. The first step is to gather sound power level data from these products. Sound power level data should be gathered in accordance with existing ANSI and/or ISO standards. Some standards, such as ANSI 12.15, may not define true operational noise emissions[r1] and thus may provide inaccurate information when that information is used to choose a hearing protection device or used to make a purchasing decision. A number of standards were systematically combined by NIOSH researchers to provide the most accurate information on sound power levels of powered hand tools used in the construction industry. This presentation will detail some of the challenges of existing ANSI 12.15 (and draft ANSI 12.41) to measure sound power levels of electric (and pneumatic) powered hand tools.

  16. Power Consideration for Three-Level Growth Models

    Science.gov (United States)

    Li, Wei; Konstantopoulos, Spyros

    2016-01-01

    The purpose of this study is extend previous methods by Raudenbush and Liu (2001) and Spybrook et al. (2011), and provide methods for power analysis of tests of treatment effects in studies of polynomial change with two levels of nesting (e.g., students and schools) where the treatment is either at the third level (e.g., school intervention) or at…

  17. User's manual for levelized power generation cost using a microcomputer

    International Nuclear Information System (INIS)

    Microcomputer programs for the estimation of levelized electrical power generation costs are described. Procedures for light-water reactor plants and coal-fired plants include capital investment cost, operation and maintenance cost, fuel cycle cost, nuclear decommissioning cost, and levelized total generation cost. Programs are written in Pascal and are run on an Apple II Plus microcomputer

  18. High-level power analysis and optimization techniques

    Science.gov (United States)

    Raghunathan, Anand

    1997-12-01

    This thesis combines two ubiquitous trends in the VLSI design world--the move towards designing at higher levels of design abstraction, and the increasing importance of power consumption as a design metric. Power estimation and optimization tools are becoming an increasingly important part of design flows, driven by a variety of requirements such as prolonging battery life in portable computing and communication devices, thermal considerations and system cooling and packaging costs, reliability issues (e.g. electromigration, ground bounce, and I-R drops in the power network), and environmental concerns. This thesis presents a suite of techniques to automatically perform power analysis and optimization for designs at the architecture or register-transfer, and behavior or algorithm levels of the design hierarchy. High-level synthesis refers to the process of synthesizing, from an abstract behavioral description, a register-transfer implementation that satisfies the desired constraints. High-level synthesis tools typically perform one or more of the following tasks: transformations, module selection, clock selection, scheduling, and resource allocation and assignment (also called resource sharing or hardware sharing). High-level synthesis techniques for minimizing the area, maximizing the performance, and enhancing the testability of the synthesized designs have been investigated. This thesis presents high-level synthesis techniques that minimize power consumption in the synthesized data paths. This thesis investigates the effects of resource sharing on the power consumption in the data path, provides techniques to efficiently estimate power consumption during resource sharing, and resource sharing algorithms to minimize power consumption. The RTL circuit that is obtained from the high-level synthesis process can be further optimized for power by applying power-reducing RTL transformations. This thesis presents macro-modeling and estimation techniques for switching

  19. Battery Energy Storage System for PV Output Power Leveling

    Directory of Open Access Journals (Sweden)

    Rajkiran Singh

    2014-01-01

    Full Text Available Fluctuating photovoltaic (PV output power reduces the reliability in power system when there is a massive penetration of PV generators. Energy storage systems that are connected to the PV generators using bidirectional isolated dc-dc converter can be utilized for compensating the fluctuating PV power. This paper presents a grid connected energy storage system based on a 2 kW full-bridge bidirectional isolated dc-dc converter and a PWM converter for PV output power leveling. This paper proposes two controllers: a current controller using the d-q synchronous reference and a phase-shift controller. The main function of the current controller is to regulate the voltage at the high-side dc, so that the voltage ratio of the high-voltage side (HVS with low-voltage side (LVS is equal to the transformer turns ratio. The phase-shift controller is employed to manage the charging and discharging modes of the battery based on PV output power and battery voltage. With the proposed system, unity power factor and efficient active power injection are achieved. The feasibility of the proposed control system is investigated using PSCAD simulation.

  20. Aerobic Capacity and Anaerobic Power Levels of the University Students

    Science.gov (United States)

    Taskin, Cengiz

    2016-01-01

    The aim of study was to analyze aerobic capacity and anaerobic power levels of the university students. Total forty university students who is department physical education and department business (age means; 21.15±1.46 years for male and age means; 20.55±1.79 years for female in department physical education), volunteered to participate in this…

  1. Design of megawatt power level heat pipe reactors

    Energy Technology Data Exchange (ETDEWEB)

    Mcclure, Patrick Ray [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Poston, David Irvin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dasari, Venkateswara Rao [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reid, Robert Stowers [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-12

    An important niche for nuclear energy is the need for power at remote locations removed from a reliable electrical grid. Nuclear energy has potential applications at strategic defense locations, theaters of battle, remote communities, and emergency locations. With proper safeguards, a 1 to 10-MWe (megawatt electric) mobile reactor system could provide robust, self-contained, and long-term power in any environment. Heat pipe-cooled fast-spectrum nuclear reactors have been identified as a candidate for these applications. Heat pipe reactors, using alkali metal heat pipes, are perfectly suited for mobile applications because their nature is inherently simpler, smaller, and more reliable than “traditional” reactors. The goal of this project was to develop a scalable conceptual design for a compact reactor and to identify scaling issues for compact heat pipe cooled reactors in general. Toward this goal two detailed concepts were developed, the first concept with more conventional materials and a power of about 2 MWe and a the second concept with less conventional materials and a power level of about 5 MWe. A series of more qualitative advanced designs were developed (with less detail) that show power levels can be pushed to approximately 30 MWe.

  2. Refurbishment, Modernization and Ageing Management Program of The 3MW TRIGA Mark-II Research Reactor of Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Salam, M. A. [Atomic Energy Research Establishment, Dhaka (Bangladesh)

    2013-07-01

    The 3 MW TRIGA MK-II research reactor of Bangladesh Atomic Energy Commission (BAEC) achieved its first criticality on 14 September 1986. The reactor has been used for manpower training, radioisotope production and various R and D activities in the field of neutron activation analysis, neutron radiography and neutron scattering. Reactor Operation and Maintenance Unit (ROMU) is responsible for operation and maintenance of the research reactor. During the past twenty seven years ROMU carried out several refurbishments, replacement, modification and modernization activities in the reactor facility. The major tasks carried out under refurbishment program were replacement of the corrosion damaged N-16 decay tank by a new one, replacement of the fouled shell and tube type heat exchanger by a plate type one, modification of the shielding arrangements around the N-16 decay tank and ECCS system and solving the radial beam port-1 leakage problem. All of these refurbishment activities were performed under an annual development project (ADP) funded by Bangladesh government. BAEC research reactor (RR) was operated by analogue console system from its commissioning to July, 2011. Old analog based console has been replaced by digital console on June, 2012. Modernization program for the reactor control console due to obsolescence and unavailability of spare parts of I and C system was vital to restore the safe operation of the reactor. Considering these facts, installation of a digital control console and I and C system based on the state-of-the-art digital technology became necessary. Reactor digital console system installation tasks were performed under another ADP funded project by Bangladesh government. Now the reactor is operating with the digital control system. Besides this, the Neutron Radiography (NR) facility has been modernized by the addition of a digital neutron radiography set-up at the tangential beam port. The Neutron Scattering (NS) facility also has been upgraded

  3. Protoflight photovoltaic power module system-level tests in the space power facility

    Science.gov (United States)

    Rivera, Juan C.; Kirch, Luke A.

    1989-01-01

    Work Package Four, which includes the NASA-Lewis and Rocketdyne, has selected an approach for the Space Station Freedom Photovoltaic (PV) Power Module flight certification that combines system level qualification and acceptance testing in the thermal vacuum environment: The protoflight vehicle approach. This approach maximizes ground test verification to assure system level performance and to minimize risk of on-orbit failures. The preliminary plans for system level thermal vacuum environmental testing of the protoflight PV Power Module in the NASA-Lewis Space Power Facility (SPF), are addressed. Details of the facility modifications to refurbish SPF, after 13 years of downtime, are briefly discussed. The results of an evaluation of the effectiveness of system level environmental testing in screening out incipient part and workmanship defects and unique failure modes are discussed. Preliminary test objectives, test hardware configurations, test support equipment, and operations are presented.

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

    International Nuclear Information System (INIS)

    Nitriding of aluminium 2011 using a radio frequency plasma at higher power levels (500 and 700 W) and lower substrate temperature (500 deg. C) resulted in higher AlN/Al2O3 ratios than obtained at 100 W and 575 deg. C. AlN/Al2O3 ratios derived from X-ray photoelectron spectroscopic analysis (and corroborated by heavy ion elastic recoil time of flight spectrometry) for treatments preformed at 100 (575 deg. C), 500 (500 deg. C) and 700 W (500 deg. C) were 1.0, 1.5 and 3.3, respectively. Scanning electron microscopy revealed that plasma nitrided surfaces obtained at higher power levels exhibited much finer nodular morphology than obtained at 100 W

  5. Criticality and Safety Parameter Studies of a 3-MW TRIGA MARK-II Research Reactor and Validation of the Generated Cross-Section Library and Computational Method

    International Nuclear Information System (INIS)

    This study deals with the analysis of some neutronics and safety parameters of the current core of a 3-MW TRIGA MARK-II research reactor and validation of the generated macroscopic cross-section library and calculational techniques by benchmarking with experimental, operational, and available Safety Analysis Report (SAR) values. The overall strategy is: (a) generation of the problem-dependent cross-section library from basic Evaluated Nuclear Data Files such as ENDF/B-VI and JENDL-3.2 with NJOY94.10+, (b) use of the WIMSD-5 package to generate a few-group neutron macroscopic cross section for all of the materials in the core and its immediate neighborhood, (c) use the three-dimensional CITATION code to perform the global analysis of the core, and (d) checking of the validity of the CITATION diffusion code with the MCNP4B2 Monte Carlo code. The ultimate objective is to establish methods for reshuffling the current core configuration to upgrade the thermal flux at irradiation locations for increased isotope production. The computational methods, tools and techniques, customization of cross-section libraries, various models for cells and supercells, and many associated utilities are standardized and established/validated for the overall neutronic analysis. The excess reactivity, neutron flux, power distribution, power peaking factors, determination of the hot spot, and fuel temperature reactivity coefficients αf in the temperature range of 45 to 1000 deg. C are studied. All the analyses are performed using the 4- and 7-group libraries of the macroscopic cross sections generated from the 69-group WIMSD-5 library. The 7-group calculations yield comparatively better agreement with the experimental value of keff and the other core parameters. The CITATION test runs using different cross-section sets based on the different models applied in the WIMSD-5 calculations show a strong influence of those models on the final integral parameter. Some of the cells are specially

  6. Device for timing and power level setting for microwave applications

    Science.gov (United States)

    Ursu, M.-P.; Buidoş, T.

    2016-08-01

    Nowadays, the microwaves are widely used for various technological processes. The microwaves are emitted by magnetrons, which have strict requirements concerning power supplies for anode and filament cathodes, intensity of magnetic field, cooling and electromagnetic shielding. The magnetrons do not tolerate any alteration of their required voltages, currents and magnetic fields, which means that their output microwave power is fixed, so the only way to alter the power level is to use time-division, by turning the magnetron on and off by repetitive time patterns. In order to attain accurate and reproducible results, as well as correct and safe operation of the microwave device, all these requirements must be fulfilled. Safe, correct and reproducible operation of the microwave appliance can be achieved by means of a specially built electronic device, which ensures accurate and reproducible exposure times, interlocking of the commands and automatic switch off when abnormal operating conditions occur. This driving device, designed and realized during the completion of Mr.Ursu's doctoral thesis, consists of a quartz time-base, several programmable frequency and duration dividers, LED displays, sensors and interlocking gates. The active and passive electronic components are placed on custom-made PCB's, designed and made by means of computer-aided applications and machines. The driving commands of the electronic device are delivered to the magnetron power supplies by means of optic zero-passing relays. The inputs of the electronic driving device can sense the status of the microwave appliance. The user is able to enter the total exposure time, the division factor that sets the output power level and, as a novelty, the clock frequency of the time divider.

  7. SEVEN LEVEL CONTROL OF SHUNT ACTIVE POWER FILTER FOR POWER QUALITY ENHANCEMENT

    Directory of Open Access Journals (Sweden)

    G. JAYAKRISHNA

    2011-09-01

    Full Text Available Shunt Active Power Filter (SAPF is one of the controllers to enhance power quality (PQ. This paper presents Hybrid Cascaded Seven-Level Inverter (HCSLI used in SAPF to compensate reactive power, improve the power factor and to suppress the total harmonic distortion (THD in supply current due to linear load and Non- Linear Diode Rectifier Loads (NLDRLs.In this paper d-q reference frame theory for reference current computation, Constant Switching Frequency Multicarrier Sub-Harmonic Pulse Width Modulation (CSFMSHPWM technique for controlling the switches of HCSLI, Fuzzy logic controller (FLC for regulating dc side capacitor voltage are proposed. The results are validated through simulation using Mat Lab/simulink with and without SAPF for linear and nonlinear loads.

  8. Experience and challenges on safeguards practices and approaches for BAEC 3 MW TRIGA Mk-II research reactor and other establishment of Bangladesh

    International Nuclear Information System (INIS)

    the only establishment in the country where nuclear materials are being used. The 3 MW TRIGA Mark-II research reactor of BAEC has been operating since September 14, 1986. The reactor is used for radioisotope production (131I, 99mTc, 46Sc), various R and D activities, manpower training and education. As a facility and material balance area, AERE facilities have been designated by the Agency (IAEA) as BDA-, BD-A and BDZ- respectively. The facilities at AERE which are of concern from safeguards point of view are the 3MW TRIGA Mk-II research reactor and the radioisotope production laboratory. The reactor facility has fuel elements and fission chambers where nuclear materials are used. Where as the radioisotope production laboratory has isotope transfer cask made from depleted uranium. Accounting of nuclear materials is carried out by maintaining and routinely updating several records as recommended by IAEA and standards prescribed/adopted by the Nuclear Safety and Radiation Control Regulations of BAEC. Nuclear fuel was first imported into the country in 1985. Fuels were loaded into the reactor core on 13 September 1986. IAEA safeguards inspectors visited the facility for the first time in 1986. Since then the facility is inspected regularly on annual basis by two or three inspectors at a time. The inventories of nuclear materials at AERE include several kilograms of 19.7% enriched uranium in the form of TRIGA fuels, several kilograms of depleted uranium in the form of shielding for the radioisotope transfer cask and a few grams of 99.3% enriched uranium in the form of fission chambers. A few of the fuels are still fresh and they have been stored in the fresh fuel storage room. Rest of the fuels is loaded into the reactor core. The facility has not yet generated any spent fuel. According to the safety analysis report (SAR), the initial core loading is capable of producing about 1278 megawatt-days of energy. But as of now, the figure for the total cumulative burn-up stands

  9. Technical basis for staffing levels at nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Shurberg, D.A.; Haber, S.B. [Brookhaven National Lab., Upton, NY (United States); Morisseau, D. [Nuclear Regulatory Commission, Washington, DC (United States)] [and others

    1995-04-01

    The objective of this project is to provide a technical basis for the establishment of criteria for minimum staffing levels of licensed and non-licensed NPP shift personnel. Minimum staffing levels for the purpose of this study, are defined as those necessary for successful accomplishment of all safety and additional functions that must be performed in order for the licensee to meet applicable regulatory requirements. This project involves a multi-faceted approach to the investigation of the issue. Relevant NRC documentation was identified and reviewed. Using the information obtained from this documentation review, a test plan was developed to aid in the collection of further information regarding the adequacy of current shift staffing levels. The test plan addresses three different activities to be conducted to provide information to the NRC for use in the assessment of current minimum staffing levels. The first activity is collection of data related to industry shift staffing practices through site visits to seven nuclear power plants. The second activity is a simulator study, which will use licensed operator crews responding to a simulated event, under two different staffing levels. Finally, workload models will be constructed for both licensed and non-licensed personnel, using a priori knowledge of the simulator scenarios with data resulting from one of the staffing levels studied in the simulator, and the data collected from the site visits. The model will then be validated against the data obtained from the second staffing level studied in the simulator. The validated model can then be used to study the impact of changing staffing-related variables on the plant shift crew`s ability to effectively mitigate an event.

  10. Management of the high-level nuclear power facilities

    International Nuclear Information System (INIS)

    This thesis approaches current issues in the management of the high power nuclear facilities and as such it appears to be important particularly for nuclear power plant operation topics. Of special interest are the failure events entailing possible catastrophic situations. The contents is structured onto ten chapters. The first chapter describes the operation regimes of the nuclear high power facilities. Highlighted here are the thesis scope and the original features of the work. The second chapter deals with operational policies developed in order to ensure the preventive maintenance of the nuclear installations. Also managing structures are described devoted to practical warranting the equipment safety function of non-classical power stations. In the third chapter cases of nuclear accidents are analyzed especially stressing the probabilistic risk and the operation regimes having in view the elimination of catastrophic events. In the fourth and fifth chapters the control of nuclear radiation emission is treated focusing the quality issue of nuclear installations required to avoid hazardous effects at level of nuclear reactor operation stage. At the same time set of operational measures is given here for preventing risks, catastrophes and chaotic situations. The chapter five presents both theoretical and practical approaches of the nuclear reactor core management concerning particularly the fuel testing, the water primary system and the quality of the involved equipment. In the sixth and seventh chapters issues of risk-quality correlations are approached as well as the structure of expert systems for monitoring the operational regimes of nuclear facilities. The efficiency of the power systems with nuclear injection is discussed and some original ideas developed in this work are evidenced in the eighth and ninth chapters. Presented are here both the operational principles and models of raising the efficiency of the interconnected nuclear stations and prices' policy

  11. Experience and challenges on safeguards practices and approaches for BAEC 3 MW TRIGA Mk-II research reactor and other establishment of Bangladesh

    International Nuclear Information System (INIS)

    Bangladesh is deeply committed to nuclear non-proliferation signing and accesses to different unilateral protocols, agreements and treaties like Nuclear Non-Proliferation Treaty (NPT), Comprehensive Test Ban Treaty (CTBT), Safeguards Agreements, Nuclear Cooperation Agreements with the USA and other countries etc. are the manifestations of such commitment. The first of such agreements, the NPT was signed in August 1979. NPT is a national commitment that the signatory country will not engage in activities related on nuclear detonations. Subsequently a bilateral agreement entitled 'Safeguards Agreements' was signed with the International Atomic Energy Agency (IAEA) in June 1982. This provides for international verification of facilities and balancing of nuclear materials. 3MW TRIGA Mark-II Research Reactor Facility of Bangladesh Atomic Energy Commission (BAEC) is inspected physically by the IAEA Safeguards Inspectors on an annual basis. For this purpose, a subsidiary arrangement was made with the IAEA, which had defined the scope of such verification. Bangladesh has also signed a Nuclear Cooperation Agreement with the USA on September 17, 1981, which facilitated export of nuclear technology from USA to Bangladesh. Bangladesh also signed another bilateral agreement entitled 'Protocol Additional to the Safeguards Agreements' with the IAEA in March 30, 2001. The main purpose of this agreement is to provide the IAEA with information on 'so called dual-purpose materials and facilities' including the front end and back end of the nuclear fuel cycle. Its enforcement required filing of an initial declaration, draft of which has been sent to the Ministry of Science, Information and Communication Technology (MOSICT) for approval and transmittal to IAEA through the office of the permanent mission in Geneva. This protocol till to-date is the highest level of verification under the nonproliferation regime. The commitment of Bangladesh to non-proliferation is adequately reflected

  12. Temporal variations in Global Seismic Stations ambient noise power levels

    Science.gov (United States)

    Ringler, A.T.; Gee, L.S.; Hutt, C.R.; McNamara, D.E.

    2010-01-01

    Recent concerns about time-dependent response changes in broadband seismometers have motivated the need for methods to monitor sensor health at Global Seismographic Network (GSN) stations. We present two new methods for monitoring temporal changes in data quality and instrument response transfer functions that are independent of Earth seismic velocity and attenuation models by comparing power levels against different baseline values. Our methods can resolve changes in both horizontal and vertical components in a broad range of periods (∼0.05 to 1,000 seconds) in near real time. In this report, we compare our methods with existing techniques and demonstrate how to resolve instrument response changes in long-period data (>100 seconds) as well as in the microseism bands (5 to 20 seconds).

  13. Retrieval of Intermediate Level Waste at Trawsfyndd Nuclear Power Station

    Energy Technology Data Exchange (ETDEWEB)

    Wall, S.; Shaw, I.

    2002-02-25

    In 1996 RWE NUKEM Limited were awarded two contracts by BNFL Magnox Generation as part of the decommissioning programme for the Trawsfynydd power station. From the normal operations of the two Magnox reactors, intermediate level waste (ILW) had accumulated on site, this was Miscellaneous Activated Components (MAC) and Fuel Element Debris (FED). The objective of these projects is retrieval of the waste from storage vaults, monitoring, packaging and immobilization in a form suitable for on site storage in the medium term and eventual disposal to a waste repository. The projects involve the design, supply, commissioning and operation of equipment to retrieve, pack and immobilize the waste, this includes recovery from vaults in both reactor and pond locations and final decommissioning and removal of plant from site after completion of waste recovery.

  14. Burnup analysis and in-core fuel management study of the 3 MW TRIGA MARK II research reactor

    International Nuclear Information System (INIS)

    The principal objective of this study is to formulate an effective optimal fuel management strategy for the TRIGA MARK II research reactor at AERE, Savar. The core management study has been performed by utilizing four basic types of information calculated for the reactor: criticality, power peaking, neutron flux and burnup calculation. This paper presents the results of the burnup calculations for TRIGA LEU fuel elements. The fuel element burnup for approximately 20 years of operation was calculated using the TRIGAP compute code. The calculation is performed in one-dimensional radial geometry in TRIGAP. Inter-comparison of TRIGAP results with other two calculations performed by MVP-BURN and MCNP4C-ORIGEN2.1 show very good agreement. Reshuffling at 20,000 MWh step provides the highest core lifetime of the reactor, which is 64,500 MWh. Besides, the study gives valuable insight into the behaviour of the reactor and will ensure better utilization and operation of the reactor in future

  15. A Rotating Speed Controller Design Method for Power Levelling by Means of Inertia Energy in Wind Power Systems

    DEFF Research Database (Denmark)

    Qin, Zian; Blaabjerg, Frede; Loh, Poh Chiang

    2015-01-01

    in the frequency domain for power leveling. Moreover, the impact of other parameters on power leveling, including the time constant of maximum power point tracking (MPPT) and the rotor inertia, are also studied. With the proposed optimal design, the power fluctuations are mitigated as much as possible, while...... the stability of the rotating speed is still guaranteed. Moreover, the oscillation of the electromagnetic torque is also reduced, and the performance of the MPPT is only weakened slightly....

  16. Estimation of radiological doses due to the failure of a single element of a 3 MW (T) TRIGA Mark-II research reactor

    International Nuclear Information System (INIS)

    Radiological doses due to the failure of a single fuel element of a 3 MW (t) TRIGA Mark-II Research Reactor was estimated for both anticipated and design basis releases considering hypothetical accident conditions. The noble gas and halogen fission product inventory has been calculated assuming a burn-up of 2000 MWd occurring in 1.8 calendar years. For both of the releases, one hundred percent of the noble gases in the fuel-cladding gap were assumed to release from the fuel element and subsequently transferred directly to the reactor hall and twenty-five percent of the halogens in the fuel-cladding gap were assumed to release from the fuel element (with the remainder assumed to plat out on the relatively cool cladding). For the removal of the fission product gases from the reactor hall to the environment, two mechanisms were considered. These are: (1) removal by the emergency ventilation system through an activated charcoal trap in the event of a design basis release and (2) removal by the normal ventilation system for anticipated release. For the first removal mechanism, the system has been designed with activated charcoal filters having an efficiency of 0% for noble gases and 99 % for halogens. For both the cases, only the bottom one-fifth of the reactor hall volume was assumed to be involved in the air circulation (i.e., the top four-fifths was considered to be stagnant). The dispersion of the escaped fission products to the environment through the stack of the reactor was estimated using a Gaussian plume model and basing on the design parameters of the TRIGA reactor as well as the meteorological data of the site. Total individual doses in the reactor hall as well as in the environment were calculated applying the methodologies described in the IAEA publications with the assumptions as mentioned above. The total dose was regarded as the doses caused by immersion in the radioactive air plume (for both noble gas and halogen), inhaled halogen and the deposited

  17. Power systems: Carbon negative at the regional level

    Science.gov (United States)

    Bauer, Nico

    2015-03-01

    Modelling of the power system on the west coast of North America shows that including bioenergy with carbon capture and sequestration technologies could enable the region to be carbon negative by 2050.

  18. Maximal anaerobic power in national level Indian players.

    OpenAIRE

    Bhanot, J. L.; Sidhu, L. S.

    1981-01-01

    The comparative study of aerobic power in different sports was conducted on 99 National Senior as well as National Junior players specialised in hockey and football, field games; volleyball and basketball, court games. The National Seniors were 27 hockey and 16 volleyball players, whereas, 32 football and 24 basketball players were the National Juniors. The maximal anaerobic power of the players was determined from maximal vertical velocity and body weight by the methods of margaria. The foot...

  19. Traction Power System Capacity Limitations at Various Traffic Levels

    OpenAIRE

    Abrahamsson, Lars; Söder, Lennart

    2011-01-01

    The aim, and main contribution, of this paper is to propose a fine-tuned fast approximator, based on neural networks, that uses aggregated traction system information as inputs and outputs. This approximator can be used as an investment planning constraint in the optimization. It considers that there is a limit on the intensity of the train traffic, depending on the strength of the power system. In the numerical examples of this paper, the approximator inputs are the power system configuratio...

  20. Maximal anaerobic power in national level Indian players.

    Science.gov (United States)

    Bhanot, J L; Sidhu, L S

    1981-12-01

    The comparative study of aerobic power in different sports was conducted on 99 National Senior as well as National Junior players specialised in hockey and football, field games; volleyball and basketball, court games. The National Seniors were 27 hockey and 16 volleyball players, whereas, 32 football and 24 basketball players were the National Juniors. The maximal anaerobic power of the players was determined from maximal vertical velocity and body weight by the methods of margaria. The football players have been found to be highest followed by hockey, volleyball and basketball players in vertical velocity. It is observed that field game players are higher than the court game players in vertical velocity and that volleyball players possess higher maximum anaerobic power than football, hockey and basketball players. PMID:7317726

  1. Cognitive Aspects of Power in a Two-Level Game

    Science.gov (United States)

    Juvina, Ion; Lebiere, Christian; Martin, Jolie; Gonzalez, Cleotilde

    The Intergroup Prisoner's Dilemma with Intragroup Power Dynamics (IPD^2) is a new game paradigm for studying human behavior in conflict situations. IPD^2 adds the concept of intragroup power to an intergroup version of the standard Iterated Prisoner's Dilemma game. We conducted an exploratory laboratory study in which individual human participants played the game against computer strategies of various complexities. We also developed a cognitive model of human decision making in this game. The model was run in place of the human participant under the same conditions as in the laboratory study. Results from the human study and the model simulations are presented and discussed, emphasizing the value of including intragroup power in game theoretic models of conflict.

  2. Design of Oil-Quenching Tank for 3 MW Wind Turbine Main Shaft Bearings%3MW风电主轴轴承淬火油槽设计

    Institute of Scientific and Technical Information of China (English)

    邵阳; 马忠超; 姚艳书

    2015-01-01

    The problems existing in heat treatment for main shaft bearings used in 3MW wind turbines are analyzed.The volume of oil-quenching tank for the bearing rings is calculated,and the structure for oil-quenching tank is rede-signed.The hardness of the bearing rings satisfies standard requirement for secondary quenching cooling process during heat treatment by adopting oil-quenching tank with top plug type and side plug type stirrers.%分析3MW风电主轴轴承热处理中存在的问题,计算轴承套圈淬火油槽的体积,重新设计淬火油槽结构,采用顶插式和侧插式组合搅拌器的淬火油槽,使3MW风电主轴轴承在热处理二次淬火冷却过程中硬度达到标准要求。

  3. A High Power Density Three-level Parallel Resonant Converter for Capacitor Charging

    OpenAIRE

    Sheng, Honggang

    2009-01-01

    This dissertation proposes a high-power, high-frequency and high-density three-level parallel resonant converter for capacitor charging. DC-DC pulsed power converters are widely used in military and medical systems, where the power density requirement is often stringent. The primary means for reducing the power converter size has been to reduce loss for reduced cooling systems and to increase the frequency for reduced passive components. Three-level resonant converters, which combine the mer...

  4. Power Constrained High-Level Synthesis of Battery Powered Digital Systems

    DEFF Research Database (Denmark)

    Nielsen, Sune Fallgaard; Madsen, Jan

    2003-01-01

    of utmost importance for battery powered embedded systems. Our approach extends the partial-clique partitioning algorithm by introducing power awareness through a heuristic algorithm which bounds the design space to those of power feasible schedules. We have applied our algorithm on a set of dataflow graphs...

  5. The development of a milliwatt-level radioisotope power source

    Science.gov (United States)

    Bugby, David C.; McBirney, Thomas R.

    1998-01-01

    Future NASA spacecraft for unmanned planetary exploration will be much smaller and require much less power than the large systems used in prior missions. The ``Powerstick'', a miniaturized isotopic electrical power generator, uses a flight-qualified, DoE-manufactured, 1.1 W Radioisotope Heater Unit (RHU) to generate the high temperature sink for a thermoelectric converter (TEC). The TEC generates sufficient electrical power (~40 mW) to trickle-charge an external rechargeable battery pack, which can then be used in low duty cycle, low power applications. The original Powerstick concept (proposed by JPL) was refined at Swales Aerospace (SA), which has: repackaged it, constructed a prototype, and performed limited testing. The prototype Powerstick is 63.5 mm (2.500'') in diameter, 76.2 mm (3.000'') long, and weighs about 0.3 kg (0.66 lb). Structural analysis indicates the Powerstick can easily survive typical launch loads. Thermal analysis indicates that over 70% of the RHU energy enters the TEC. This paper will describe the design and analysis of the Powerstick prototype and present the key test results.

  6. The advantages and disadvantages of centralized control of air power at operational level

    Science.gov (United States)

    Arisoy, Uǧur

    2014-05-01

    People do not want to see and hear a war. In today's world, if war is inevitable, the use of air power is seen as the preferable means of conducting operations instead of financially burdensome land battles which are more likely to cause heavy loss of life. The use of Air Power has gained importance in NATO operations in the Post-Cold War era. For example, air power has undertaken a decisive role from the beginning to the end of the operation in Libya. From this point of view, the most important issue to consider is how to direct air power more effectively at operational level. NATO's Core JFAC (Joint Force Air Command) was established in 2012 to control joint air power at operational level from a single center. US had experienced JFAC aproach in the Operation Desert Storm in 1991. UK, France, Germany, Italy and Spain are also directing their air power from their JFAC structures. Joint air power can be directed from a single center at operational level by means of JFAC. JFAC aproach provides complex planning progress of Air Power to be controled faster in a single center. An Air Power with a large number of aircrafts, long range missiles of cutting-edge technology may have difficulties in achieving results unless directed effectively. In this article, directing air power more effectively at operational level has been studied in the framework of directing air power from a single center carried out by SWOT analysis technique. "Directing Air Power at operational level from a single center similar to JFAC-like structure" is compared with "Directing Air Power at operational level from two centers similar to AC (Air Command) + CAOC (Combined Air Operations Center) structure" As a result of this study, it is assessed that directing air power at operational level from a single center would bring effectiveness to the air campaign. The study examines directing air power at operational level. Developments at political, strategic and tactical levels have been ignored.

  7. Analysis of power gating in different hierarchical levels of 2MB cache, considering variation

    Science.gov (United States)

    Jafari, Mohsen; Imani, Mohsen; Fathipour, Morteza

    2015-09-01

    This article reintroduces power gating technique in different hierarchical levels of static random-access memory (SRAM) design including cell, row, bank and entire cache memory in 16 nm Fin field effect transistor. Different structures of SRAM cells such as 6T, 8T, 9T and 10T are used in design of 2MB cache memory. The power reduction of the entire cache memory employing cell-level optimisation is 99.7% with the expense of area and other stability overheads. The power saving of the cell-level optimisation is 3× (1.2×) higher than power gating in cache (bank) level due to its superior selectivity. The access delay times are allowed to increase by 4% in the same energy delay product to achieve the best power reduction for each supply voltages and optimisation levels. The results show the row-level power gating is the best for optimising the power of the entire cache with lowest drawbacks. Comparisons of cells show that the cells whose bodies have higher power consumption are the best candidates for power gating technique in row-level optimisation. The technique has the lowest percentage of saving in minimum energy point (MEP) of the design. The power gating also improves the variation of power in all structures by at least 70%.

  8. 77 FR 40092 - License Amendment To Increase the Maximum Reactor Power Level, Florida Power & Light Company, St...

    Science.gov (United States)

    2012-07-06

    ... and limit high temperatures to the mixing zone area specified in the IWFP. The NRC also analyzed the... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION License Amendment To Increase the Maximum Reactor Power Level, Florida Power & Light Company,...

  9. Photovoltaic Shading Testbed for Module-Level Power Electronics

    Energy Technology Data Exchange (ETDEWEB)

    Deline, C.; Meydbray, J.; Donovan, M.; Forrest, J.

    2012-05-01

    This document describes a repeatable test procedure that attempts to simulate shading situations, as would be experienced by typical residential rooftop photovoltaic (PV) systems. This type of shading test is particularly useful to evaluate the impact of different power conversion setups, including microinverters, DC power optimizers and string inverters, on overall system performance. The performance results are weighted based on annual estimates of shade to predict annual performance improvement. A trial run of the test procedure was conducted with a side by side comparison of a string inverter with a microinverter, both operating on identical 8kW solar arrays. Considering three different shade weighting conditions, the microinverter was found to increase production by 3.7% under light shading, 7.8% under moderate shading, and 12.3% under heavy shading, relative to the reference string inverter case. Detail is provided in this document to allow duplication of the test method at different test installations and for different power electronics devices.

  10. Computational analysis of Bangladesh 3 MW TRIGA research reactor using MCNP4C, JENDL-3.3 and ENDF/B-Vl data libraries

    Energy Technology Data Exchange (ETDEWEB)

    Huda, M.Q. [Institute of Nuclear Science and Technology, Atomic Energy Research Establishment, Ganakbari, Savar, GPO Box 3787, Dhaka-1000 (Bangladesh)]. E-mail: quamrul@dhaka.net

    2006-08-15

    The three-dimensional continuous energy Monte Carlo code MCNP4C was used to develop a versatile and accurate full-core model of the 3 MW TRIGA MARK II research reactor at Atomic Energy Research Establishment, Savar, Dhaka, Bangladesh. The model represents in detail all components of the core with literally no physical approximation. All fresh fuel and control elements as well as the vicinity of the core were precisely described. Validation of the JENDL-3.3 and ENDF/BVI continuous energy cross-section data for MCNP4C was performed against some well-known benchmark lattices. For TRIGA analysis, data from JENDL-3.3 and ENDF/B-VI in combination with the JENDL-3.2 and ENDF/B-V data files (for {sup nat}Zr, {sup nat}Mo, {sup nat}Cr, {sup nat}Fe, {sup nat}Ni, {sup nat}Si, and {sup nat}Mg) at 300 K evaluations were used. Full S({alpha}, {beta}) scattering functions from ENDF/B-V for Zr in ZrH, H in ZrH and water molecule, and for graphite were used in both cases. The validation of the model was performed against the criticality and reactivity benchmark experiments of the TRIGA reactor. There is {approx}20.0% decrease of thermal neutron flux occurs when the thermal library is removed during the calculation. Effect of erbium isotope that is present in the TRIGA fuel was also studied. In addition to the effective multiplication values, the well-known integral parameters: {delta} {sup 28}, {delta} {sup 25}, {rho} {sup 25}, and C {sup *} were calculated and compared for both JENDL3.3 and ENDF/B-VI libraries and were found to be in very good agreement. Results are also reported for most of the analyses performed by JENDL-3.2 and ENDF/B-V data libraries.

  11. Analysis of the DNB ratio and the loss-of-flow accident (LOFA) of the 3 MW TRIGA MARK II research reactor

    International Nuclear Information System (INIS)

    The PARET code was used to analyze two most important thermal hydraulic design parameters of the 3 MW TRIGA MARK II research reactor. The first design parameters is the DNB (departure from nucleate boiling) ratio, which is defined as the ratio of the critical heat flux to the heat flux achieved in the core and was computed by means of a suitable correlation as defined in PARET code. The reactor core should be designed so as to prevent the DNBR from dropping below a chosen value under a high heat flux transient condition for the most adverse set of mechanical and coolant conditions. Over the length 0.381 m of the hottest channel the DNB ratio varies, starting from 3.8951 to 5.4031, with a minimum of 2.7851. The peak heat flux occurs at the axial center of the fuel elements; therefore the DNB ratio is minimum at this location. The second design parameter is the loss-of-flow accident scenario of the TRIGA reactor. The Bergles-Rohsenow correlation was selected for detecting onset of nucleate boiling, the transition model with the McAdams correlation was included for fully developed two-phase flow, and the Seider-Tate correlation was used for the single-phase forced convection regime. The loss-of-flow transient after a trip time of 4.08 sec at 85% of loss of normal flow for the TRIGA core shows a peak temperature of 709.22 C in the fuel centerline and 131.94 C in the clad and 46.63 C in the coolant exit of the hottest channel. The transient was terminated at 15% of nominal flow after about 48.0 sec. The time at which the reversal of coolant flow starts is about 67.0 sec. (author)

  12. Toward the Next Level of PCB Usage in Power Electronic Converters

    NARCIS (Netherlands)

    De Jong, E.C.W.; Ferreira, B.J.A.; Bauer, P.

    2008-01-01

    A means for power electronics to exploit the level of 3-D packaging already being implemented in compact consumer products, such as digital cameras, is investigated in order to increase its power density. The increase in functionality and usage of printed circuit board (PCB) in power electronic conv

  13. Robust model-based steam generator level control in nuclear power plant

    International Nuclear Information System (INIS)

    Economic feasibility of a power plant requires smooth and uninterrupted plant operation in the face of varying electrical power demand. The feed-water system in a power plant is a major contributor to plant unavailability. The purpose of this paper is to present a general framework for addressing all aspects of this problem and design, analyze and evaluate a water level controller for Steam Generator (SG) and using robust controller design procedure, Linear Quadratic Gaussian with Loop Transfer Recovery, LQG/LTR for low power and high power range. Simulations show that the proposed controller improves transient response of (SG) water level and demonstrate its superiority to existing conventional PI controllers. (author)

  14. Power Analysis for Cross Level Mediation in CRTs

    Science.gov (United States)

    Kelcey, Ben

    2014-01-01

    A common design in education research for interventions operating at a group or cluster level is a cluster randomized trial (CRT) (Bloom, 2005). In CRTs, intact clusters (e.g., schools) are assigned to treatment conditions rather than individuals (e.g., students) and are frequently an effective way to study interventions because they permit…

  15. User instructions for levelized power generation cost codes using an IBM-type PC

    International Nuclear Information System (INIS)

    Programs for the calculation of levelized power generation costs using an IBM or compatible PC are described. Cost calculations for nuclear plants and coal-fired plants include capital investment cost, operation and maintenance cost, fuel cycle cost, decommissioning cost, and total levelized power generation cost. 7 refs., 36 figs., 4 tabs

  16. User instructions for levelized power generation cost codes using an IBM-type PC

    Energy Technology Data Exchange (ETDEWEB)

    Coen, J.J.; Delene, J.G.

    1989-01-01

    Programs for the calculation of levelized power generation costs using an IBM or compatible PC are described. Cost calculations for nuclear plants and coal-fired plants include capital investment cost, operation and maintenance cost, fuel cycle cost, decommissioning cost, and total levelized power generation cost. 7 refs., 36 figs., 4 tabs.

  17. Power quality enhancement at distribution level utilizing the unified power quality conditioner (UPQC)

    Science.gov (United States)

    Khadkikar, Vinod

    The present doctoral work is based on the philosophy of optimal utilization of the available resources in a most effective and efficient way to improve the product efficiency and to reduce the overall cost. This work proposes a novel control philosophy termed as power angle control (PAC), in which both the series and shunt inverters share the load reactive power in co-ordination with each other without affecting the basic UPQC compensation capabilities. This eventually results in a better utilization of the series inverter, reduction in the shunt inverter rating to some extent and ultimately in the reduction of the overall cost of UPQC. Moreover, in this thesis work several other control approaches are also proposed, such as, unit vector template generation, quadrature voltage injection, generalized single-phase p-q theory and novel current unbalance compensation approach. All the developed concepts are successfully validated through digital simulation as well as extensive experimental investigations. Keywords. power quality, active power filter, unified power quality conditioner, reactive power compensation, harmonics compensation.

  18. Nuclear power plant personnel entry level qualifications and training

    International Nuclear Information System (INIS)

    This paper summarizes the early results and current status of a research program at ORNL which is intended to provide the methods and technical basis for NRC to initiate the use of the Systems Approach to Training (SAT) in the evaluation of training programs and entry level qualifications for NPP control room personnel. The program is an outgrowth of previous studies of simulator hardware and simulator training requirements under the Safety Related Operator Actions Program which recommended adaptation of a systems methodology to development and evaluation of NPP training programs

  19. ACCOUNTING OF REACTIVE POWER COMPENSATION LEVEL AT PAYMENT CALCULATION OF TECHNOLOGICAL CONSUMPTION (LOSSES OF ELECTRIC POWER FOR ITS TRANSMISSION IN POWER NETWORK

    Directory of Open Access Journals (Sweden)

    E. P. Zabello

    2005-01-01

    Full Text Available The method is proposed to make a correction in payment for consumption of reactive energy and power which is attributed to deviation of actual activation energy losses for reactive power compensation from their standard value. It is recommended to calculate standard loss values for every voltage level and actual loss values are to be determined with the help of application of remote electronic accounting means in the current mode of power consumption.

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

    DEFF Research Database (Denmark)

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

    2008-01-01

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

  1. Design and Analysis of Multi Level D-STATCOM to Improve the Power Quality

    Directory of Open Access Journals (Sweden)

    Dinesh. Badavath,

    2014-01-01

    Full Text Available In the last decade, the electrical power quality issue has been the main concern of the power companies. Power quality is defined as the index which both the delivery and consumption of electric power affect on the performance of electrical apparatus. From a customer point of view, a power quality problem can be defined as any problem is manifested on voltage, current, or frequency deviation that results in power failure. The power electronics progressive, especially in flexible alternating-current transmission system (FACTS and custom power devices, affects power quality improvement. This paper presents an investigation of seven-Level Cascaded H - bridge (CHB Inverter as Distribution Static Compensator (DSTATCOM in Power System (PS for compensation of reactive power and harmonics. The advantages of CHB inverter are low harmonic distortion, reduced number of switches and suppression of switching losses. The DSTATCOM helps to improve the power factor and eliminate the Total Harmonics Distortion (THD drawn from a Non-Liner Diode Rectifier Load (NLDRL. The D-Q reference frame theory is used to generate the reference compensating currents for DSTATCOM while Proportional and Integral (PI control is used for capacitor dc voltage regulation. A CHB Inverter is considered for shunt compensation of a 11 Kv distribution system. Finally a level shifted PWM (LSPWM and phase shifted PWM (PSPWM techniques are adopted to investigate the performance of CHB Inverter. The results are obtained through Matlab/Simulink software package.

  2. Optimization of the Electric Power Leveling System Using a Superconducting Magnetic Energy Storage with Genetic Algorithm

    Science.gov (United States)

    Funabiki, Shigeyuki; Tanaka, Toshihiko; Fujii, Toshinori

    A new optimization method of the electric power leveling system using an SMES is proposed. The SMES is parallelly connected with rolling mills in steel works. The leveling control is based on fuzzy reasoning. The SMES capacity and the scaling factors of the fuzzy controller will be optimized so that the power leveling control can be achieved and then the total cost of the added SMES cost and reduced contract electricity rate becomes lower. The optimization is carried out using the genetic algorithm and the cost reduction of 7.76 billion yen can be achieved. It is confirmed by the power leveling simulation that the proposed optimization method is very effective for designing the power leveling system.

  3. Procedural justice climate and group power distance: an examination of cross-level interaction effects.

    Science.gov (United States)

    Yang, Jixia; Mossholder, Kevin W; Peng, T K

    2007-05-01

    In this article, the authors extend research on the cross-level effects of procedural justice climate by theorizing and testing its interaction with group power distance. The results indicated that group power distance moderated the relationships between procedural justice climate and individual-level outcomes (organizational commitment and organization-directed citizenship behavior). More specifically, a larger group power distance was found to attenuate the positive cross-level effects of procedural justice climate. Implications for procedural justice climate research are discussed. PMID:17484550

  4. Transparency powers levels in Yb 3+-doped fiber due to temperature changes

    Science.gov (United States)

    de la Cruz-May, L.; Flores-Gil, A.; Mejía, E. B.; Rodríguez-Rodriguez, J. H.; Álvarez-Chávez, J. A.

    2011-03-01

    The critical power level provides an objective tool for the determination of the maximum power available in a fiber laser based on physical parameters such as core diameter, temperature, and absorption and emission cross section for both the pump and laser wavelengths. This work presents a theoretical study of critical power levels when Ytterbium-doped fibers are exposed to changes of temperatures. We found that critical power curves extend their wavelength dependence, ranging from 1 μm to 1.2-μm when fibers were heated up 300 K. However, critical power values were rather high compared to the values obtained at room temperature. Nevertheless, low critical powers were obtained at low temperatures as 77 K in a reduced interval of wavelengths, i.e., from 1-μm to 1.1-μm.

  5. The Level of Power Quality Measurement and Evaluation in A Stone Crusher Plant

    Directory of Open Access Journals (Sweden)

    Mustafa ŞEKKELİ

    2009-03-01

    Full Text Available Both electric utilities and end users of electric power are becoming increasingly concerned about the quality of electric power. Quality of electrical energy in the electrical system that is requested continuous power (uninterrupted power, constant frequency and with constant amplitude can be explained by sinusoidal voltage. Deformation of voltage in the form of sinusoidal waveform is explained as a harmonic. Harmonics are most important factors in decreasing quality of energy in the electrical system. In industrial plants, existence of harmocins and voltage drop, causes serious problems both in plant and network. This problem affects the cost. In this study, a power quality measurements are carried out in stone crusher plant. Harmonics and voltage drop has been measured and evaluated with the power analyzer. In the power quality measurements, harmonic level of the plant is not so bad. However, it is recommended that compensation system with harmonic elimination can be established in plant.

  6. Optimization of Electric Power Leveling Systems by a Novel Cluster-Structured GA with Masking

    Science.gov (United States)

    Itoh, Jyunpei; Fujii, Toshinori; Funabiki, Shigeyuki

    Power fluctuations of the rolling mill may cause the instability of electric power systems, and increase the cost of the electric power facility and electricity charges. Therefore, in order to compensate the power fluctuations, the development of the electric power-leveling systems (EPLS) is very important in the future electric power system. The EPLS with a SMES has been proposed as one of the countermeasures for the electric power quality improvement. However, the SMES is very expensive and it is difficult to decide the gains of the controller. It is essential in the practical use that the reduction of SMES capacity is realized. This paper proposes a new optimization method of the EPLS. The proposed algorithm is Cluster-Structured GA with Masking (CSGA). The optimization of the EPLS can be achieved by the proposed CSGA compared to the GA.

  7. System Level Power Management for Embedded Rtos: An Object Oriented Approach

    Directory of Open Access Journals (Sweden)

    Ankur Agarwal

    2009-11-01

    Full Text Available Power management systems for embedded devices can be developed in real-time operating system (RTOS or in applications. If power management policies are applied in operating system (OS, then designers and developers will not have to worry about complex power management algorithms and techniques. They can rather concentrate on application development. The OS contains specific and accurate information about the various tasks being executed. An RTOS further has a comprehensive set of power management application programming interfaces (APIs for both device drivers and applications within a power management component. Therefore, it is logical to place policies and algorithms in the OS that can place components not being used into lower power states. This can significantly reduce the system energy consumption. We present here an abstract model of a system power manager (PM, device power managers, and application power managers. We present relationship and interactions of these managers with each other using Unified Modeling Language (UML class diagrams, sequence diagrams and state charts. We recommend that the PM must be implemented at the OS level in any embedded device. We also recommend the interfaces for interactions between PM and the devices power manager, as well as PM and application power manager. Device driver and application developers can easily use this object oriented approach to make the embedded system more power efficient, easy to maintain, and faster to develop.

  8. Building America Case Study: Photovoltaic Systems with Module-Level Power Electronics

    Energy Technology Data Exchange (ETDEWEB)

    2015-09-01

    Direct current (DC) power optimizers and microinverters (together known as module-level power electronics, or MLPE) are one of the fastest growing market segments in the solar industry. According to GTM Research in The Global PV Inverter Landscape 2015, over 55% of all residential photovoltaic (PV) installations in the United States used some form of MLPE in 2014.

  9. Bidirectional Five-Level Power Processing Interface for Low Voltage Battery Energy Storage System

    Science.gov (United States)

    Huang, Jain-Yi; Jou, Hurng-Liahng; Wu, Kuen-Der; Lin, You-Si; Wu, Jinn-Chang

    A bidirectional five-level power processing interface for low voltage battery energy storage system (BESS) is developed in this paper. This BESS consists of a bidirectional five-level DC-AC converter, a bidirectional dual boost/buck DC-DC converter and a battery set. This five-level DC-AC converter includes a bidirectional full-bridge converter and a bidirectional dual buck DC-DC converter. The five-level power processing interface can charge power to the battery set form the utility or discharge the power from the battery set to the utility depending on the demanded operation of user. A hardware prototype is developed to verify the performance of this BESS. Experimental results show the performance of the developed BESS is as expected.

  10. A Fast Approach for System-Level Power Modeling and Simulation

    Institute of Scientific and Technical Information of China (English)

    XIAJun; ZOUXuecheng

    2004-01-01

    Power is one of the main constraints in SOC (System-on-a-chip) design. System-level power modeling and simulation help to reduce the power dissipation in early stage. But by reason of the variability of system architecture, the amount of simulation is vast which result in the simulation time is unacceptable. On the basis of previous work, a modified hybrid approach for core-based system-level power modeling is proposed in this paper, which enables SOC designers to estimate system power consumption under different core parameters and just simulates the system only once. Thereafter designers can make a trade-off rapidly between performance characters (such as power, area, speed and test, etc) and make a decision about which architecture is the best solution to implement system functionality. The key of our approach is to help the core designers to provide a power metric function to the core users and the effectiveness and efficiency of our approach hinge on whether the IP provider could provide an accurate power model of each core. A linear model is chosen to describe the relationship between power consumption and parameters and least-square-error is selected as the optimization criterion to mitigate error. Although the power is given as an example, our approach can be applied to speed and area performance trade-off also because speed and area performance modeling is simpler relatively.

  11. Low-Carbon Based Multi-Objective Bi-Level Power Dispatching under Uncertainty

    Directory of Open Access Journals (Sweden)

    Xiaoyang Zhou

    2016-06-01

    Full Text Available This research examines a low-carbon power dispatch problem under uncertainty. A hybrid uncertain multi-objective bi-level model with one leader and multiple followers is established to support the decision making of power dispatch and generation. The upper level decision maker is the regional power grid corporation which allocates power quotas to each follower based on the objectives of reasonable returns, a small power surplus and low carbon emissions. The lower level decision makers are the power generation groups which decide on their respective power generation plans and prices to ensure the highest total revenue under consideration of government subsidies, environmental costs and the carbon trading. Random and fuzzy variables are adopted to describe the uncertain factors and chance constrained and expected value programming are used to handle the hybrid uncertain model. The bi-level models are then transformed into solvable single level models using a satisfaction method. Finally, a detailed case study and comparative analyses are presented to test the proposed models and approaches to validate the effectiveness and illustrate the advantages.

  12. Metal clad active fibres for power scaling and thermal management at kW power levels.

    Science.gov (United States)

    Daniel, Jae M O; Simakov, Nikita; Hemming, Alexander; Clarkson, W Andrew; Haub, John

    2016-08-01

    We present a new approach to high power fibre laser design, consisting of a polymer-free all-glass optical fibre waveguide directly overclad with a high thermal conductivity metal coating. This metal clad active fibre allows a significant reduction in thermal resistance between the active fibre and the laser heat-sink as well as a significant increase in the operating temperature range. In this paper we show the results of a detailed thermal analysis of both polymer and metal coated active fibres under thermal loads typical of kW fibre laser systems. Through several different experiments we present the first demonstration of a cladding pumped aluminium-coated fibre laser and the first demonstration of efficient operation of a cladding-pumped fibre laser at temperatures of greater than 400 °C. Finally, we highlight the versatility of this approach through operation of a passively (radiatively) cooled ytterbium fibre laser head at an output power of 405 W in a compact and ultralight package weighing less than 100 g. PMID:27505822

  13. Thermal analysis of multi-MW two-level wind power converter

    OpenAIRE

    Zhou, Dao; Blaabjerg, Frede; Mogens, Lau; Tonnes, Michael

    2012-01-01

    In this paper, the multi-MW wind turbine of partial-scale and full-scale two-level power converter with DFIG and direct-drive PMSG are designed and compared in terms of their thermal performance. Simulations of different configurations regarding loss distribution and junction temperature in the power device in the whole range of wind speed are presented and analyzed. It is concluded that in both partial-scale and full-scale power converter the most thermal stressed power device in the generat...

  14. The Level of Difficulty and Discrimination Power of the Basic Knowledge and Skills Examination (EXHCOBA.

    Directory of Open Access Journals (Sweden)

    Eduardo Backhoff Escudero

    2000-05-01

    Full Text Available The Basic Knowledge and Skills Examination (EXHCOBA is one of the few great-scale examinations in Mexico which has been publishing its psychometric parameters.  In this paper we describe the  item analysis results, regarding the exam’s difficulty level and discrimination power.  Results show that most of the items have a medium difficulty and a high discrimination power.  They also reveal that the mathematics items have better discrimination power levels than the ones which belong to social science.

  15. Power estimation for intellectual property-based digital systems at the architectural level

    Directory of Open Access Journals (Sweden)

    Yaseer Arafat Durrani

    2014-09-01

    We present an efficient power macro-modeling technique at the architectural level for digital electronic systems. This technique estimates the power dissipation of intellectual property (IP components to their statistical knowledge of the primary inputs/outputs. During the power estimation method, the sequence of an input stream is generated by a genetic algorithm (GA using input metrics and the macro-model function to construct a set of functions that map the input metrics of a macro-block to its output metrics. Then, a Monte Carlo zero-delay simulation is performed and the power dissipation is predicted by a macro-model function. The most important contribution of the technique is that it allows fast power estimation of IP-based design by the simple addition of individual power consumption. This makes the power modeling of SoCs an easy task that permits evaluation of power features at the architectural level. In order to evaluate our model, we have constructed IP-based digital systems using different IP macro-blocks. In experiments with an individual IP macro-block the average error is 1–2% and for an entire IP-based system with interconnects, the error range is from 9% to 15%. The preliminary results are effective and our macro-model provides accurate power estimation.

  16. Impact of high level penetration of Wind Turbines on Power System Transient Stability

    DEFF Research Database (Denmark)

    Kalogiannis, Theodoros; Llano, Enrique Muller; Hoseinzadeh, Bakhtyar;

    2015-01-01

    One of the most relevant aspects in power systems is their reliability and robustness of maintaining the stability under large disturbances. System stability is a crucial aspect to consider when expanding the network, e.g. while increasing the levels of wind power penetration. Wind turbine...... generators differ from the conventional ones in their inertial contribution to the grid, therefore, in most cases the ability of the system to maintain a stable operation is declined. To investigate this, two standard models are designed in PowerFactory software. The first is used to characterize system...... components, the response of the wind turbines and thereupon to validate them, whereas the second is used to estimate the maximum levels of wind power penetration. Those levels mainly depend on the spinning reserve, the inertia of the system and the severity of the event. Rate of change of frequency will...

  17. Scalability of components for kW-level average power few-cycle lasers.

    Science.gov (United States)

    Hädrich, Steffen; Rothhardt, Jan; Demmler, Stefan; Tschernajew, Maxim; Hoffmann, Armin; Krebs, Manuel; Liem, Andreas; de Vries, Oliver; Plötner, Marco; Fabian, Simone; Schreiber, Thomas; Limpert, Jens; Tünnermann, Andreas

    2016-03-01

    In this paper, the average power scalability of components that can be used for intense few-cycle lasers based on nonlinear compression of modern femtosecond solid-state lasers is investigated. The key components of such a setup, namely, the gas-filled waveguides, laser windows, chirped mirrors for pulse compression and low dispersion mirrors for beam collimation, focusing, and beam steering are tested under high-average-power operation using a kilowatt cw laser. We demonstrate the long-term stable transmission of kW-level average power through a hollow capillary and a Kagome-type photonic crystal fiber. In addition, we show that sapphire substrates significantly improve the average power capability of metal-coated mirrors. Ultimately, ultrabroadband dielectric mirrors show negligible heating up to 1 kW of average power. In summary, a technology for scaling of few-cycle lasers up to 1 kW of average power and beyond is presented.

  18. Optimization of E-DCH channel power ratios to maximize link level efficiency

    DEFF Research Database (Denmark)

    Zarco, Carlos Ruben Delgado; Malone, Jaime Tito; Wigard, Jeroen;

    2006-01-01

    For the WCDMA/HSUPA concept, a key to ensuring high spectral efficiency is to correctly adjust the transmission power ratios among the data and control channels. This paper provides optimal values for the power ratio between the Enhanced-Dedicated Physical Data Channel (E-DPDCH) and the Dedicated...... Physical Control Channel (DPCCH) from a Link Efficiency (LE) point of view. LE has been defined as the ratio between the average number of correctly received bits per second and the average total transmitted power. The optimization was carried out by testing different E-DPDCH to DPCCH power ratios in an...... HSUPA link level simulator for different bit rates. This simulator includes Hybrid ARQ (HARQ) and optimal power ratios are extracted for different Retransmission Sequence Number (RSN) targets. For Vehicular-A 30 km/h conditions, the optimal power ratios per code show only minor dependency on the bit...

  19. Scalability of components for kW-level average power few-cycle lasers.

    Science.gov (United States)

    Hädrich, Steffen; Rothhardt, Jan; Demmler, Stefan; Tschernajew, Maxim; Hoffmann, Armin; Krebs, Manuel; Liem, Andreas; de Vries, Oliver; Plötner, Marco; Fabian, Simone; Schreiber, Thomas; Limpert, Jens; Tünnermann, Andreas

    2016-03-01

    In this paper, the average power scalability of components that can be used for intense few-cycle lasers based on nonlinear compression of modern femtosecond solid-state lasers is investigated. The key components of such a setup, namely, the gas-filled waveguides, laser windows, chirped mirrors for pulse compression and low dispersion mirrors for beam collimation, focusing, and beam steering are tested under high-average-power operation using a kilowatt cw laser. We demonstrate the long-term stable transmission of kW-level average power through a hollow capillary and a Kagome-type photonic crystal fiber. In addition, we show that sapphire substrates significantly improve the average power capability of metal-coated mirrors. Ultimately, ultrabroadband dielectric mirrors show negligible heating up to 1 kW of average power. In summary, a technology for scaling of few-cycle lasers up to 1 kW of average power and beyond is presented. PMID:26974623

  20. User's manual for levelized power generation cost using an IBM PC

    International Nuclear Information System (INIS)

    Programs for the estimation of levelized electric power generation costs using the BASIC interpreter on an IBM PC are described. Procedures for light-water reactor plants and coal-fired plants include capital investment cost, operation and maintenance cost, fuel cycle cost, nuclear decommissioning cost, and levelized total generation cost

  1. Four-level time decomposition quasi-static power flow and successive disturbances analysis. [Power system disturbances

    Energy Technology Data Exchange (ETDEWEB)

    Jovanovic, S.M. (Nikola Tesla Inst., Belgrade (YU))

    1990-01-01

    This paper presents a model and an appropriate numerical procedure for a four-level time decomposition quasi-static power flow and successive disturbances analysis of power systems. The analysis consists of the sequential computation of the zero, primary, secondary and tertiary quasi-static states and of the estimation of successive structural disturbances during the 1200 s dynamics after a structural disturbance. The model is developed by detailed inspection of the time decomposition characteristics of automatic protection and control devices. Adequate speed of the numerical procedure is attained by a specific application of the inversion matrix lemma and the decoupled model constant coefficient matrices. The four-level time decomposition quasi-static method is intended for security and emergency analysis. (author).

  2. A control strategy for a three-level unified power quality conditioner

    OpenAIRE

    Monteiro, Luís F. C.; Costa, José C. C.; Aredes, Maurício; Afonso, João L.

    2005-01-01

    In this work a control strategy for a three-level Unified Power Quality Conditioner (UPQC) is introduced. Basically, this control strategy is based on the set of active and non-active (reactive) power definitions in the time domain, which have been proposed by Fryze in the 30´s of the last century. The goal of this work consists in expand this control strategy to deal with three-level converters. The use of three-level converters allows a better performance of the equipment, by reducing...

  3. Three-phase power supply, output 60v and 100a, with unit power factor and low RFI level

    Directory of Open Access Journals (Sweden)

    João Batista Vieira Júnior

    2003-01-01

    Full Text Available This paper presents a three-phase rectifier, unit power factor, non-dissipative commutation in DC-DC converter and synchronized control in frequency, working with 89% of global efficiency and low level do RFI. The proposed structure allows the operation with high switching frequency. The output voltage is controlled by PWM with a constant frequency. The operation principle, theoretical analysis from DC converter, relevant equations, current balance control technique and experimental results, are shown in this paper.

  4. Wafer-level chip-scale packaging analog and power semiconductor applications

    CERN Document Server

    Qu, Shichun

    2015-01-01

    This book presents a state-of-art and in-depth overview in analog and power WLCSP design, material characterization, reliability, and modeling. Recent advances in analog and power electronic WLCSP packaging are presented based on the development of analog technology and power device integration. The book covers in detail how advances in semiconductor content, analog and power advanced WLCSP design, assembly, materials, and reliability have co-enabled significant advances in fan-in and fan-out with redistributed layer (RDL) of analog and power device capability during recent years. Along with new analog and power WLCSP development, the role of modeling is a key to assure successful package design. An overview of the analog and power WLCSP modeling and typical thermal, electrical, and stress modeling methodologies is also provided. This book also: ·         Covers the development of wafer-level power discrete packaging with regular wafer-level design concepts and directly bumping technology ·    �...

  5. Nonlinear Power-Level Control of the MHTGR Only with the Feedback Loop of Helium Temperature

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2013-02-01

    Full Text Available Power-level control is a crucial technique for the safe, stable and efficient operation of modular high temperature gas-cooled nuclear reactors (MHTGRs, which have strong inherent safety features and high outlet temperatures. The current power-level controllers of the MHTGRs need measurements of both the nuclear power and the helium temperature, which cannot provide satisfactory control performance and can even induce large oscillations when the neutron sensors are in error. In order to improve the fault tolerance of the control system, it is important to develop a power-level control strategy that only requires the helium temperature. The basis for developing this kind of control law is to give a state-observer of the MHTGR a relationship that only needs the measurement of helium temperature. With this in mind, a novel nonlinear state observer which only needs the measurement of helium temperature is proposed. This observer is globally convergent if there is no disturbance, and has the L2 disturbance attenuation performance if the disturbance is nonzero. The separation principle of this observer is also proven, which denotes that this observer can recover the performance of both globally asymptotic stabilizers and L2 disturbance attenuators. Then, a new dynamic output feedback power-level control strategy is established, which is composed of this observer and the well-built static state-feedback power-level control based upon iterative dissipation assignment (IDA-PLC. Finally, numerical simulation results show the high performance and feasibility of this newly-built dynamic output feedback power-level controller.

  6. US power plant sites at risk of future sea-level rise

    Science.gov (United States)

    Bierkandt, R.; Auffhammer, M.; Levermann, A.

    2015-12-01

    Unmitigated greenhouse gas emissions may increase global mean sea-level by about 1 meter during this century. Such elevation of the mean sea-level enhances the risk of flooding of coastal areas. We compute the power capacity that is currently out-of-reach of a 100-year coastal flooding but will be exposed to such a flood by the end of the century for different US states, if no adaptation measures are taken. The additional exposed capacity varies strongly among states. For Delaware it is 80% of the mean generated power load. For New York this number is 63% and for Florida 43%. The capacity that needs additional protection compared to today increases by more than 250% for Texas, 90% for Florida and 70% for New York. Current development in power plant building points towards a reduced future exposure to sea-level rise: proposed and planned power plants are less exposed than those which are currently operating. However, power plants that have been retired or canceled were less exposed than those operating at present. If sea-level rise is properly accounted for in future planning, an adaptation to sea-level rise may be costly but possible.

  7. US power plant sites at risk of future sea-level rise

    International Nuclear Information System (INIS)

    Unmitigated greenhouse gas emissions may increase global mean sea-level by about 1 meter during this century. Such elevation of the mean sea-level enhances the risk of flooding of coastal areas. We compute the power capacity that is currently out-of-reach of a 100-year coastal flooding but will be exposed to such a flood by the end of the century for different US states, if no adaptation measures are taken. The additional exposed capacity varies strongly among states. For Delaware it is 80% of the mean generated power load. For New York this number is 63% and for Florida 43%. The capacity that needs additional protection compared to today increases by more than 250% for Texas, 90% for Florida and 70% for New York. Current development in power plant building points towards a reduced future exposure to sea-level rise: proposed and planned power plants are less exposed than those which are currently operating. However, power plants that have been retired or canceled were less exposed than those operating at present. If sea-level rise is properly accounted for in future planning, an adaptation to sea-level rise may be costly but possible. (letter)

  8. Disentangling Bargaining Power from Individual and Household Level to Institutions: Evidence on Women’s Position in Ethiopia

    NARCIS (Netherlands)

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

    2010-01-01

    textabstractSUMMARY Women's bargaining power is generally analyzed only with individual level and household level variables. We add a third level, namely institutional bargaining power. We define this as bargaining power which one party freely derives from unequal social norms. In the bargaining lit

  9. Design and implementation of a DSP with multi-level low power strategies for cochlear implants

    Institute of Scientific and Technical Information of China (English)

    Mai Songping; Zhang Chun; Chao Jun; Wang Zhihua

    2009-01-01

    This paper presents the design and implementation of a low power digital signal processor (THUCIDSP-1) targeting at application for cochlear implants. Multi-level low power strategies including algorithm optimization, operand isolation, clock gating and memory partitioning are adopted in the processor design to reduce the power consumption. Experimental results show that the complexity of the Continuous Interleaved Sampling (CIS) algorithm is reduced by more than 80% and the power dissipation of the hardware alone is reduced by about 25% with the low power methods. The THUCIDSP-1 prototype, fabricated in 0.18-μm standard CMOS process, consumes only 1.91 mW when executing the CIS algorithm at 3 MHz.

  10. Fourier power spectrum characteristics of face photographs : attractiveness perception depends on low-level image properties.

    OpenAIRE

    Claudia Menzel; Hayn-Leichsenring, Gregor U.; Oliver Langner; Holger Wiese; Christoph Redies

    2015-01-01

    We investigated whether low-level processed image properties that are shared by natural scenes and artworks - but not veridical face photographs - affect the perception of facial attractiveness and age. Specifically, we considered the slope of the radially averaged Fourier power spectrum in a log-log plot. This slope is a measure of the distribution of special frequency power in an image. Images of natural scenes and artworks possess - compared to face images - a relatively shallow slope (i.e...

  11. The management of mixed low-level radioactivewaste in the nuclear power industry

    International Nuclear Information System (INIS)

    As a result of investigations sponsored by the nuclear power industry, the definition of mixed low-level radioactive waste (mixed waste) in the industry is clarified. A methodology for estimating the annual generation rate of mixed waste is presented and its application to a typical nuclear power plant is illustrated. Effective management practices to minimize the generation of mixed waste are described and strategies to deal with unavoidable mixed waste are identified

  12. Design and operation of 140 GHz gyrotron oscillators for power levels up to 1 MW CW

    Energy Technology Data Exchange (ETDEWEB)

    Jory, H.; Bier, R.; Craig, L.J.; Felch, K.; Ives, L.; Lopez, N.; Spang, S.

    1986-12-01

    Varian has designed and tested 140 GHz gyrotron oscillators that have generated output powers of 100 kW CW and 200 kW for 1 ms pulses. Upcoming tubes will be designed to operate at power levels of 200 kW CW and ultimately up to 1 MW CW. The important design considerations which are addressed in the higher power tubes include the design of the electron gun, interaction circuit, and output window. These issues will be discussed and the results of the earlier 140 GHz gyrotron work at Varian will be summarized.

  13. Level-one modules library for DSNP: Dynamic Simulator for Nuclear Power-plants

    International Nuclear Information System (INIS)

    The Dynamic Simulator for Nuclear Power-plants (DSNP) is a system of programs and data sets by which a nuclear power plant or part thereof can be simulated at different levels of sophistication. The acronym DSNP is used interchangeably for the DSNP language, for the DSNP precompiler, for the DSNP libraries, and for the DSNP document generator. The DSNP language is a set of simple block oriented statements, which together with the appropriate data, comprise a simulation of a nuclear power plant. The majority of the DSNP statements will result in the inclusion of a simulated physical module into the program. FORTRAN statements can be inserted with no restrictions among DSNP statements

  14. Level-one modules library for DSNP: Dynamic Simulator for Nuclear Power-plants

    Energy Technology Data Exchange (ETDEWEB)

    Saphier, D.

    1978-09-01

    The Dynamic Simulator for Nuclear Power-plants (DSNP) is a system of programs and data sets by which a nuclear power plant or part thereof can be simulated at different levels of sophistication. The acronym DSNP is used interchangeably for the DSNP language, for the DSNP precompiler, for the DSNP libraries, and for the DSNP document generator. The DSNP language is a set of simple block oriented statements, which together with the appropriate data, comprise a simulation of a nuclear power plant. The majority of the DSNP statements will result in the inclusion of a simulated physical module into the program. FORTRAN statements can be inserted with no restrictions among DSNP statements.

  15. Amendment of standard for procedures of level 1 probabilistic risk assessment of nuclear power plants during power operation

    International Nuclear Information System (INIS)

    A standard which is intended to provide requirements and methodologies for conducting level 1 probabilistic risk assessment (PRA) was amended. In this standard, PRA is carried out to evaluate the risk of nuclear power plants by evaluating the core damage frequencies due to internal initiating events during power operation. This standard was approved and published by the Atomic Energy Society of Japan (AESJ) on the deliberations at the Subcommittee on Level 1 PRA under the Risk Technical Committee of the AESJ Standards Committee. AESJ formulated and issued this document after deliberation by the Risk Technical Committee and the Standards Committee. PRA of a nuclear power plant is a probabilistic approach for comprehensively and quantitatively assessing plant risk. This involves quantitative analysis of accident scenarios up to core damage and of the further evolution of events after core damage, with careful attention to events that are related to core or fuel damage, finally to arrive at an estimation of event frequencies and consequences. In Japan, PRA has been implemented to evaluate the validity of Accident Management Strategies and the quantitative safety of nuclear power plants in the Periodic Safety Review. Furthermore, in the regulatory area, the Nuclear Regulation Authority, which is the new regulatory authority founded in 2012, intends to utilize PRA in their new safety regulation positively. As the validity of PRA has come to be accepted, preservation of the quality and transparency of PRA has become important issues. Recognizing that preparation of a standard for PRA procedure is effective in addressing these issues, the AESJ standards committee is preparing a procedures guide for nuclear facilities. As described above, this standard replaces the 2008 issue - A Standard for Procedures of Probabilistic Safety Assessment of Nuclear Power Plants during Power Operation (Level 1 PSA):2008 - of the same standard. We decided to make this amendment because five

  16. Architecture-level performance/power tradeoff in network processor design

    Institute of Scientific and Technical Information of China (English)

    CHEN Hong-song; JI Zhen-zhou; HU Ming-zeng

    2007-01-01

    Network processors are used in the core node of network to flexibly process packet streams. With the increase of performance, the power of network processor increases fast, and power and cooling become a bottleneck. Architecture-level power conscious design must go beyond low-level circuit design. Architectural power and performance tradeoff should be considered at the same time. Simulation is an efficient method to design modern network processor before making chip. In order to achieve the tradeoff between performance and power,the processor simulator is used to design the architecture of network processor. Using Netbench, Commubench benchmark and processor simulator-SimpleScalar, the performance and power of network processor are quantitatively evaluated. New performance tradeoff evaluation metric is proposed to analyze the architecture of network processor. Based on the high performance Intel IXP 2800 Network processor configuration, optimized instruction fetch width and speed 、instruction issue width, instruction window size are analyzed and selected. Simulation results show that the tradeoff design method makes the usage of network processor more effectively. The optimal key parameters of network processor are important in architecture-level design. It is meaningful for the next generation network processor design.

  17. Battery Recharging Issue for a Two-Power-Level Flywheel System

    Directory of Open Access Journals (Sweden)

    Janaína Gonçalves de Oliveira

    2010-01-01

    Full Text Available A novel battery recharging system for an all-electric driveline comprising a flywheel with a permanent magnet double wound synchronous machine (motor/generator is presented. The double winding enables two voltage levels and two different power levels. This topology supersedes other all-electric drivelines. The battery operates in a low-power regime supplying the average power whereas the flywheel delivers and absorbs power peaks, which are up to a higher order of magnitude. The topology presents new challenges for the power conversion system, which is the focus of this investigation. The main challenge is the control of the power flow to the battery when the vehicle is parked despite the decay of the flywheel machine voltage; which is dependent on its charge state, that is, rotational speed. The design and simulation of an unidirectional DC/DC buck/boost converter for a variable rotational speed flywheel is presented. Conventional power electronic converters are used in a new application, which can maintain a constant current or voltage on the battery side. Successful PI current control has been implemented and simulated, together with the complete closed loop system.

  18. Dynamic Output Feedback Power-Level Control for the MHTGR Based On Iterative Damping Assignment

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2012-06-01

    Full Text Available Because of its strong inherent safety features and high outlet temperature, the modular high temperature gas-cooled nuclear reactor (MHTGR is already seen as the central part of the next generation of nuclear plants. Such power plants are being considered for industrial applications with a wide range of power levels, and thus power-level control is an important technique for their efficient and stable operation. Stimulated by the high regulation performance provided by nonlinear controllers, a novel dynamic output-feedback nonlinear power-level regulator is developed in this paper based on the technique of iterative damping assignment (IDA. This control strategy can provide the L2 disturbance attenuation performance under modeling uncertainty or exterior disturbance, and can also guarantee the globally asymptotic closed-loop stability without uncertainty and disturbance. This newly built control strategy is then applied to the power-level regulation of the HTR-PM plant, and numerical simulation results show both the feasibility and high performance of this newly-built control strategy. Furthermore, the relationship between the values of the parameters and the performance of this controller is not only illustrated numerically but also analyzed theoretically.

  19. Design for reliability in power electronics in renewable energy systems – status and future

    DEFF Research Database (Denmark)

    Wang, Huai; Blaabjerg, Frede; Ma, Ke;

    2013-01-01

    maintenance costs, and herefore, low Levelized-Cost-of-Energy (LCOE) of renewable energy systems. This paper presents the prior-art Design for Reliability (DFR) process for power converters and addresses the paradigm shift to Physics-of-Failure (PoF) approach and mission profile based analysis. Moreover......Advances in power electronics enable efficient and flexible interconnection of renewable sources, loads and electric grids. While targets concerning efficiency of power converters are within reach, recent research endeavors to predict and improve their reliability to ensure high availability, low......, the lifetime prediction of reliability-critical components IGBT modules is discussed in a 2.3 MW wind power converter. Finally, the challenges and opportunities to achieve more reliable power electronic converters are discussed....

  20. Decentralized load frequency control on each power plant. Hatsudensho level ni okeru bunsangata fuka shuhasu seigyo

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, E.; Hasegawa, J. (HOkkaido Universtiy, Sapporo (Jpaan))

    1991-02-20

    Because of relatively decreasing hydraulic power plants, it becomes difficult to secure an electric power capacity needed for load frequency control of the electric power system. Accordingly, application is studied of the modern control theory based on a state equation instead of the classic control theory. To improve control characteristic by transmitting as little information as possible, decentralized control on each power plant level is studied and applied to a model. The following is a summarized conclusion: By detecting by an integral compensator and controlling variables which are equal to voltage phase angle deviations, frequency deviations or interchange power deviations can be controlled without information on interconnected-power-line tide deviations or interchange power deviations. Designing and practical operation of this system are easy because the control system is structured by the information including frequency deviations only from each power plant. Moreover, if some state variables are not available, the control system can be designed with a dynamic compensator. 6 refs., 4 figs., 2 tabs.

  1. Method for Calculating CO2 Emissions from the Power Sector at the Provincial Level in China

    Institute of Scientific and Technical Information of China (English)

    MA Cui-Mei; GE Quan-Sheng

    2014-01-01

    Based on the detailed origins of each province’s electricity consumption, a new method for calculating CO2 emissions from the power sector at the provincial level in China is proposed. With this so-called consumer responsibility method, the emissions embodied in imported electricity are calculated with source-specific emission factors. Using the new method, we estimate CO2 emissions in 2005 and 2010. Compared with those derived from the producer responsibility method, the power exporters’ emissions decreased sharply. The emissions from the power sector in Inner Mongolia, the largest power exporter of China, decreased by 109 Mt in 2010. The value is equivalent to those from Shaanxi’s power production and Canada’s power and heat production. In contrast, the importers’ emissions increased substantially. The emissions from the power sector in Hebei, the largest power importer of China, increased by 74 Mt. Emissions of Beijing, increased by 60 Mt (320%), in 2010. Thus, we suggest that the Chinese government should take the emissions, as calculated from the consumption perspective, into account when formulating and assessing local CO2 emission reduction targets.

  2. Optimization of Electric Power Leveling Systems by using Taper-Off-Reflectance Particle Swarm Optimization

    Science.gov (United States)

    Makino, Yohei; Fujii, Toshinori; Imai, Jun; Funabiki, Shigeyuki

    Recently, it is desired to develop energy control technologies for environmental issues such as global warming and exhaustion of fossil fuel. Power fluctuations in large power consumers may cause the instability of electric power systems and increase the cost of the electric power facility and electricity charges. Developing the electric power-leveling systems (EPLS) to compensate the power fluctuations is necessary for future electric power systems. Now, EPLS with an SMES have been proposed as one of the countermeasures for the electric power quality improvement. The SMES is superior to other energy storage devices in response and storage efficiency. The authors proposed the EPLS based on fussy control with the SMES. For this practical implementation, optimizing control gain and SMES capacity is an important issue. This paper proposes a new optimization method of the EPLS. The proposed algorithm is novel particle swarm optimization based on taper-off reflectance (TRPSO). The proposed TRPSO optimizes the design variables of the EPLS efficiently and effectively.

  3. System-level power optimization for real-time distributed embedded systems

    Science.gov (United States)

    Luo, Jiong

    Power optimization is one of the crucial design considerations for modern electronic systems. In this thesis, we present several system-level power optimization techniques for real-time distributed embedded systems, based on dynamic voltage scaling, dynamic power management, and management of peak power and variance of the power profile. Dynamic voltage scaling has been widely acknowledged as an important and powerful technique to trade off dynamic power consumption and delay. Efficient dynamic voltage scaling requires effective variable-voltage scheduling mechanisms that can adjust voltages and clock frequencies adaptively based on workloads and timing constraints. For this purpose, we propose static variable-voltage scheduling algorithms utilizing criticalpath driven timing analysis for the case when tasks are assumed to have uniform switching activities, as well as energy-gradient driven slack allocation for a more general scenario. The proposed techniques can achieve closeto-optimal power savings with very low computational complexity, without violating any real-time constraints. We also present algorithms for power-efficient joint scheduling of multi-rate periodic task graphs along with soft aperiodic tasks. The power issue is addressed through both dynamic voltage scaling and power management. Periodic task graphs are scheduled statically. Flexibility is introduced into the static schedule to allow the on-line scheduler to make local changes to PE schedules through resource reclaiming and slack stealing, without interfering with the validity of the global schedule. We provide a unified framework in which the response times of aperiodic tasks and power consumption are dynamically optimized simultaneously. Interconnection network fabrics point to a new generation of power-efficient and scalable interconnection architectures for distributed embedded systems. As the system bandwidth continues to increase, interconnection networks become power/energy limited as

  4. Power Flow Control through a Multi-Level H-Bridge-based Power Converter for Universal and Flexible Power Management in Future Electrical Grids

    DEFF Research Database (Denmark)

    Iov, Florin; Bifaretti, Steffano; Zanchetta, Pericle;

    2008-01-01

    systems) on the AC side, and linked together at DC side by suitable DC isolation modules. Each port of the UNIFLEX-PM system employs a conversion structure based on a three-phase 7-level AC-DC cascaded converter. Effective and accurate power flow control is demonstrated through simulation in Matlab...... and Simulink environment on a simplified model based on a two-port structure and using a Stationery Reference Frame based control solution. Control of different Power flow profiles has been successfully tested in numerous network conditions such as voltage unbalance, frequency excursions and harmonic...

  5. Energy Use and Power Levels in New Monitors and Personal Computers

    Energy Technology Data Exchange (ETDEWEB)

    Roberson, Judy A.; Homan, Gregory K.; Mahajan, Akshay; Nordman, Bruce; Webber, Carrie A.; Brown, Richard E.; McWhinney, Marla; Koomey, Jonathan G.

    2002-07-23

    Our research was conducted in support of the EPA ENERGY STAR Office Equipment program, whose goal is to reduce the amount of electricity consumed by office equipment in the U.S. The most energy-efficient models in each office equipment category are eligible for the ENERGY STAR label, which consumers can use to identify and select efficient products. As the efficiency of each category improves over time, the ENERGY STAR criteria need to be revised accordingly. The purpose of this study was to provide reliable data on the energy consumption of the newest personal computers and monitors that the EPA can use to evaluate revisions to current ENERGY STAR criteria as well as to improve the accuracy of ENERGY STAR program savings estimates. We report the results of measuring the power consumption and power management capabilities of a sample of new monitors and computers. These results will be used to improve estimates of program energy savings and carbon emission reductions, and to inform rev isions of the ENERGY STAR criteria for these products. Our sample consists of 35 monitors and 26 computers manufactured between July 2000 and October 2001; it includes cathode ray tube (CRT) and liquid crystal display (LCD) monitors, Macintosh and Intel-architecture computers, desktop and laptop computers, and integrated computer systems, in which power consumption of the computer and monitor cannot be measured separately. For each machine we measured power consumption when off, on, and in each low-power level. We identify trends in and opportunities to reduce power consumption in new personal computers and monitors. Our results include a trend among monitor manufacturers to provide a single very low low-power level, well below the current ENERGY STAR criteria for sleep power consumption. These very low sleep power results mean that energy consumed when monitors are off or in active use has become more important in terms of contribution to the overall unit energy consumption (UEC

  6. Thermal analysis of multi-MW two-level wind power converter

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede; Mogens, Lau;

    2012-01-01

    In this paper, the multi-MW wind turbine of partial-scale and full-scale two-level power converter with DFIG and direct-drive PMSG are designed and compared in terms of their thermal performance. Simulations of different configurations regarding loss distribution and junction temperature in the p......In this paper, the multi-MW wind turbine of partial-scale and full-scale two-level power converter with DFIG and direct-drive PMSG are designed and compared in terms of their thermal performance. Simulations of different configurations regarding loss distribution and junction temperature...... in the power device in the whole range of wind speed are presented and analyzed. It is concluded that in both partial-scale and full-scale power converter the most thermal stressed power device in the generator-side converter will have higher mean junction temperature and larger junction temperature...... fluctuation compared to grid-side converter at the rated wind speed. Moreover, the thermal performance of the generator-side converter in the partial-scale power converter becomes crucial around the synchronous operating point and should be considered carefully....

  7. A Polymer Optical Fiber Fuel Level Sensor: Application to Paramotoring and Powered Paragliding

    OpenAIRE

    David Sánchez Montero; Carmen Vázquez; Pedro Contreras Lallana

    2012-01-01

    A low-cost intensity-based polymer optical fiber (POF) sensor for fuel level measurements in paramotoring and powered paragliding is presented, exploiting the advantages of the optical fiber sensing technology. Experimental results demonstrate that the best option can be performed by stripping the fiber at the desired discrete points to measure the fuel level as well as with a gauge-shape fiber bending. The prototype has a good linearity, better than 4% full scale (F.S.), and sensitivity arou...

  8. A review of studies on low-level vibrations as a source of electric power generation

    OpenAIRE

    RAHMATİAN, Mohammad Ali; RAHMATİAN, Mohammad Rasoul; RAHİMZADEH, Hamed

    2015-01-01

    Abstract. Recent advances in low power VLSI design, with a low duty cycle has been able to resolve wireless sensor problems. In addition, researchers are looking to generate electrical energy from vibrations. The present paper discusses the low level vibration sources and their use in piezoelectric circuit for the production of electrical energy. The simulation results show that this scheme can convert low-level vibrations in nature, home environment, workplace, etc. into electrical energy.

  9. The natural radioactive level of the coal, coal cinder and slag from power plants

    International Nuclear Information System (INIS)

    The -ray spectrometer was used to analyze the natural radioactive level of the coal from Urumqi, Yi li and Ha mi areas; coal cinder and slag from China power plant and state power plant in Urumqi. The average value of and of coal is 5.54, 3.51, 69.15 from Urumqi; 9.59, 4.02, 72.95 from Yi li; 7.42, 4.87, 88.32 from Ha mi; the coal cinder is 29.31, 15.57, 111.39 from China power plant; 24.67, 16.22, 133.98 from state power plant, respectively. The result reveals that the coal cinder's application range has no limit according to national standard. (authors)

  10. Improvement of High-Power Three-Level Explosion-Proof Inverters Using Soft Switching Control Based on Optimized Power-Loss Algorithm

    Directory of Open Access Journals (Sweden)

    Shi-Zhou Xu

    2015-01-01

    Full Text Available The high-power three-level explosion-proof inverters demand high thermal stability of power devices, and a set of theories and methods is needed to achieve an accurate power-loss calculation of power devices, to establish heat dissipation model, and ultimately to reduce the power loss to improve thermal stability of system. In this paper, the principle of neutral point clamped three-level (NPC3L inverter is elaborated firstly, and a fourth-order RC equivalent circuit of IGBT is derived, on which basis the power-loss model of IGBT and the optimized maternal power-loss thermal model, using an optimized power-loss algorithm, are established. Secondly, in accordance with the optimized maternal power-loss thermal model, the generic formulas of power-loss calculation are deduced to calculate the power-loss modification values of NPC3L and soft switching three-level (S3L inverters, which will be the thermal sources during thermal analysis for maternal power-loss thermal models. Finally, the experiment conducted on the 2.1 MW experimental platform shows that S3L inverter has the same excellent output characteristics with NPC3L inverter, reduces the power loss significantly by 213 W in each half-bridge, and decreases the temperature by 10°C, coinciding with the theoretical calculation, which verifies the accuracy of optimized power-loss algorithm and the effectiveness of the improvement.

  11. Influence of the power level of an ultra-sonic system on dental cavity preparation.

    Science.gov (United States)

    Josgrilberg, Erika Botelho; Guimarães, Murilo de Sousa; Pansani, Cyneu Aguiar; Cordeiro, Rita de Cássia Loiola

    2007-01-01

    The aim of this study was to evaluate the shape of dental cavities made with the CVDentus system using different ultrasound power levels. One standard cavity was made on the buccal aspect of 15 bovine incisors with a CVDentus cylindrical bur (82142). The sample was divided into three groups: G1-ultrasound with power II; G2-ultrasound with power III; and G3-ultrasound with power IV. A standardizing device was used to obtain standardized preparations and ultrasound was applied during one minute in each dental preparation. The cavities were sectioned in the middle, allowing observation of the cavity's profile with a magnifying glass, and width and depth measurement using the Leica Qwin program. The Kruskal-Wallis (p<0.05) and Dunn statistical analyses demonstrated differences between the dental cavity shapes when powers III and IV were used. However, the cavities that were made with power III presented dimensions similar to those of the bur used for preparation. We concluded that the power recommended by the manufacturer (III) is the most adequate for use with the CVDentus system.

  12. Estimating Brand Level Demand Elasticities and Measuring Market Power for Regular Carbonated Soft Drinks

    OpenAIRE

    Langan, Glenn E.; Cotterill, Ronald W.

    1994-01-01

    This paper reports econometric estimation of brand level demand (AIDS) elasticities for regular carbonated soft drinks using Information Resources, Inc. panel data. Own and cross price elasticities are used to measure actual and hypothetical market power that would arise from potential mergers or collusive pricing arrangements.

  13. The Evolution of Power System Planning with High Levels of Variable Renewable Generation

    Energy Technology Data Exchange (ETDEWEB)

    Katz, Jessica [National Renewable Energy Lab. (NREL), Golden, CO (United States); Milligan, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    Greening the Grid provides technical assistance to energy system planners, regulators, and grid operators to overcome challenges associated with integrating variable renewable energy into the grid. This document, part of the Greening the Grid introduces the evolution of power system planning with high levels of variable renewable generation.

  14. Empirical LTE Smartphone Power Model with DRX Operation for System Level Simulations

    DEFF Research Database (Denmark)

    Lauridsen, Mads; Noël, Laurent; Mogensen, Preben

    2013-01-01

    An LTE smartphone power model is presented to enable academia and industry to evaluate users’ battery life on system level. The model is based on empirical measurements on a smartphone using a second generation LTE chipset, and the model includes functions of receive and transmit data rates...

  15. Prospective Physics Teachers' Level of Understanding Energy, Power and Force Concepts

    Science.gov (United States)

    Saglam-Arslan, Aysegul; Kurnaz, Mehmet Altan

    2009-01-01

    The aim of this study is to determine prospective physics teachers' level of understanding of the concepts of energy and the related concepts of force and power. The study was carried out with the participation of 56 physics education department students at a university in Karadeniz region. All participants had previously taken an introductory…

  16. Review of practicing Level-2 probabilistic safety analysis for Chinese nuclear power plants

    International Nuclear Information System (INIS)

    Existing studies about Level-2 PSA (Probabilistic Safety Analysis) in the world, covering NUREG-1150, IAEA-SSG-4, 50-P-8 and Level-2 plant PSA reports for AP1000 and EPR, serve in this paper as the basis of a literature study aimed at determining guidelines to practice Level-2 PSA in Chinese commercial nuclear power plants. We recapitulate the main technical elements composing Level-2 PSA: the familiarization with plant data and systems, interface with Level-1, containment performance analysis, accident progression and containment event tree analysis, source term and release category analysis, sensitivity, importance and uncertainty analysis, and the relationship between them. At last, outcomes of Level-2 PSA are presented. (author)

  17. Development of a Review Guide for a Level-3 PSA of Nuclear Power Plants

    International Nuclear Information System (INIS)

    A probabilistic safety assessment (PSA) provides a systematic analysis to identify and quantify all the risks that a plant imposes to the operators, general public and the environment. The main benefits of a PSA is to provide insights into the safety aspects of a plant design, performance, and the potential environmental impacts of postulated accidents, including the identification of dominant risk contributors, and a comparison of the options for reducing a risk. Among the three levels of a PSA, a Level-3 PSA provides insights into the relative importance of a accident prevention and mitigative measures expressed in terms of the adverse consequences for the health of the public, and the contamination of land, air, water, and foodstuffs. Finally, a Level-3 PSA provides insights into the relative effectiveness of emergency response planning aspects of an off-site accident management, and into the economic impacts. Regulatory bodies are generally responsible for the specification of safety criteria which can be related to PSAs at Level-1, -2, and -3. Examples of these criteria are the frequency of a severe core damage for a Level-1, and the frequency of large releases of radionuclides for a Level-2 PSA. The most commonly used Level-3 related safety criteria are early and cancer fatality risks. The regulatory body in Korea has developed the review guides for the Level-1 and -2 PSA. And the current regulatory structure for the licensing of nuclear power plants is established for an LWR-oriented structure. However, the accomplishment of a Level-3 PSA as well as Level-1 and -2 PSA is necessary in order to establish the risk-informed and performance-based regulatory structure for the licensing of future nuclear power plants. In such a situation, the need for the accomplishment of a Level-3 PSA is increasing. Therefore, the main goal of this study is to develop a review guide for the Level-3 PSA

  18. Improvement of High-Power Three-Level Explosion-Proof Inverters Using Soft Switching Control Based on Optimized Power-Loss Algorithm

    OpenAIRE

    Shi-Zhou Xu; Feng-You He

    2015-01-01

    The high-power three-level explosion-proof inverters demand high thermal stability of power devices, and a set of theories and methods is needed to achieve an accurate power-loss calculation of power devices, to establish heat dissipation model, and ultimately to reduce the power loss to improve thermal stability of system. In this paper, the principle of neutral point clamped three-level (NPC3L) inverter is elaborated firstly, and a fourth-order RC equivalent circuit of IGBT is derived, on w...

  19. Application of Back Propagation Neural Network to Drum Level Control in Thermal Power Plants

    Directory of Open Access Journals (Sweden)

    Preeti Manke

    2012-03-01

    Full Text Available The paper describes the development and testing of a neural network based drum level controller for sub-critical thermal power plant boilers. Experimental data obtained from an operational coal fired power plant (500MW Thermal Power Station, Korba, India is used to train the neural network. This model proposes a simple training algorithm for a class of nonlinear systems, which enables the neural network to be trained with the output errors of the controlled plant. The only a priori knowledge of the controlled plant is the direction of its output response. Due to its simple structure and algorithm, and good performance, the proposed controller has high potential for handling difficult problems in process-control systems. The Artificial neural networks (ANN modeling can significantly reduce the frequency of deviations and the degree of deviation of the water level in the drum. The ANN model to be applied for the boiler feed system in the power plant will not only increase the efficiency of the system but also shall considerably reduce the tripping of the power plant.

  20. Survey of ambient electromagnetic and radio-frequency interference levels in nuclear power plants

    International Nuclear Information System (INIS)

    This document reports the results of a survey of ambient electromagnetic conditions in representative nuclear power plants. The U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research engaged the Oak Ridge National Laboratory (ORNL) to perform these measurements to characterize the electromagnetic interference (EMI) and radio-frequency interference (RFI) levels that can be expected in nuclear power plant environments. This survey is the first of its kind, being based on long-term unattended observations. The data presented in this report were measured at eight different nuclear units and required 14 months to collect. A representative sampling of power plant conditions (reactor type, operating mode, site location) monitored over extended observation periods (up to 5 weeks) were selected to more completely determine the characteristic electromagnetic environment for nuclear power plants. Radiated electric fields were measured over the frequency range of 5 MHz to 8 GHz. Radiated magnetic fields and conducted EMI events were measured over the frequency range of 305 Hz to 5 MHz. Highest strength observations of the electromagnetic ambient environment across all measurement conditions at each site provide frequency-dependent profiles for EMI/RFI levels in nuclear power plants

  1. A stationary reference frame current control for a multi-level H-bridge power converter for universal and flexible power management in future electricity network

    DEFF Research Database (Denmark)

    Ciobotaru, Mihai; Iov, Florin; Zanchetta, Pericle;

    2008-01-01

    More "green" power provided by Distributed Generation will enter into the European electricity network in the near future. In order to control the power flow and to ensure proper and secure operation of this future grid, with an increased level of the renewable power, new power electronic...... converters for grid connection of renewable sources will be needed. These power converters must be able to provide intelligent power management as well as ancillary services. This paper assesses a control method based on the stationary reference frame with Proportional-Resonant current controllers...... for a multi-level cascaded H-bridges power converter used for grid applications. Harmonic content in the Point of Common Coupling, system response for bidirectional power flow, voltage and frequency excursions as well as voltage unbalances and asymmetries and low voltage ride-though capabilities are studied....

  2. Computer-based control of nuclear power information systems at international level

    International Nuclear Information System (INIS)

    In most highly industrialized countries of the world information plays major role in anti-nuclear campaign. Information and discussions on nuclear power need critical and objective analysis before the structured information presentation to the public to avoid bias anti-nuclear information on one side and neglect of great risk in nuclear power. This research is developing a computer-based information system for the control of nuclear power at international level. The system is to provide easy and fast information highways for the followings: (1) Low Regulatory dose and activity limit as level of high danger for individuals and public. (2) Provision of relevant technical or scientific education among the information carriers in the nuclear power countries. The research is on fact oriented investigation about radioactivity. It also deals with fact oriented education about nuclear accidents and safety. A standard procedure for dissemination of latest findings using technical and scientific experts in nuclear technology is developed. The information highway clearly analyzes the factual information about radiation risk and nuclear energy. Radiation cannot be removed from our environment. The necessity of radiation utilizations defines nuclear energy as two-edge sword. It is therefore, possible to use computer-based information system in projecting and dissemination of expert knowledge about nuclear technology positively and also to use it in directing the public on the safety and control of the nuclear energy. The computer-based information highway for nuclear energy technology is to assist in scientific research and technological development at international level. (author)

  3. Multi-spacecraft measurement of anisotropic power levels and scaling in solar wind turbulence

    Directory of Open Access Journals (Sweden)

    K. T. Osman

    2009-08-01

    Full Text Available Measurements by the four Cluster spacecraft in the solar wind are used to determine quantitatively the field-aligned anisotropy of magnetohydrodynamic inertial range turbulence power levels and spectral indexes. We find, using time-lagged second order structure functions, that the spectral index is near 2 around the field-parallel direction, which is consistent with a "critical balance" turbulent cascade. Solar wind fluctuations are found to be anisotropic with power mainly in wavevectors perpendicular to the mean field, where the spectral index is around 5/3.

  4. Photovoltaic Shading Testbed for Module-Level Power Electronics: 2016 Performance Data Update

    Energy Technology Data Exchange (ETDEWEB)

    Deline, Chris [National Renewable Energy Lab. (NREL), Golden, CO (United States); Meydbray, Jenya [PV Evolution Labs (PVEL), Davis, CA (United States); Donovan, Matt [PV Evolution Labs (PVEL), Davis, CA (United States)

    2016-09-01

    The 2012 NREL report 'Photovoltaic Shading Testbed for Module-Level Power Electronics' provides a standard methodology for estimating the performance benefit of distributed power electronics under partial shading conditions. Since the release of the report, experiments have been conducted for a number of products and for different system configurations. Drawing from these experiences, updates to the test and analysis methods are recommended. Proposed changes in data processing have the benefit of reducing the sensitivity to measurement errors and weather variability, as well as bringing the updated performance score in line with measured and simulated values of the shade recovery benefit of distributed PV power electronics. Also, due to the emergence of new technologies including sub-module embedded power electronics, the shading method has been extended to include power electronics that operate at a finer granularity than the module level. An update to the method is proposed to account for these emerging technologies that respond to shading differently than module-level devices. The partial shading test remains a repeatable test procedure that attempts to simulate shading situations as would be experienced by typical residential or commercial rooftop photovoltaic (PV) systems. Performance data for multiple products tested using this method are discussed, based on equipment from Enphase, Solar Edge, Maxim Integrated and SMA. In general, the annual recovery of shading losses from the module-level electronics evaluated is 25-35%, with the major difference between different trials being related to the number of parallel strings in the test installation rather than differences between the equipment tested. Appendix D data has been added in this update.

  5. Biographical learning in top-level coaching - personal styles and the power of practical sense

    DEFF Research Database (Denmark)

    Christensen, Mette Krogh

    : Biographical learning in top-level coaching - personal styles and the power of practical sense. There is a growing body of studies in sports coaching cultures, comprising research focusing on the individual learning processes and life histories of top-level coaches. Even if top-level sport has become...... increasingly professionalized, the role of the top-level coach and the developmental pathways of the coaches differ widely in both areas of experience and amount of experience. In this paper I draw on theories on biographical learning, idiosyncratic learning and development of coaching expertise. This paper...... explores the relation between these kinds of learning processes and the coaches’ development of practical sense of talent. I base the paper on a sociological analysis of in-depth interviews with eight Danish top-level football coaches about their pathways to expertise. Results illustrate two interwoven...

  6. Explosive power of lower limbs in rhythmic gymnastics athletes in different competitive levels

    Directory of Open Access Journals (Sweden)

    Amanda Batista SANTOS

    2016-03-01

    Full Text Available Abstract The explosive power in Rhythmic Gymnastics shows itself in the great majority of movements and elements performed by the gymnasts, particularly in the jumps, which are essential corporal movements in this sport. The training directed to the development of jumping capacity presents a large quantity of exercises which aim to improve muscular power in the lower limbs and therefore the impulsion capacity. The vertical impulsion is an important measure used to calculate the explosive power of the lower limbs and is directly connected to the success that the gymnast will be able to achieve. Therefore, the aim of this study is to evaluate the height of two jumps in the RG (stag jump and Cossack jump in contact mat Ergojump, which calculates the jump height in connection with the flight timing, executed by national level junior gymnasts and to compare them to the results of the Junior National Team - in total 30 junior gymnasts with 13.73 ± 0.17 years old. Furthermore, to compare the levels of explosive power of preferred lower limb (PLL and non-preferred lower limb (NPLL of all gymnasts in the study, in order to verify eventual functional asymmetries. For the statistical analysis we used Parametric Tests (t Test and Nonparametric (Mann-Whitney Test and Wilcoxon Test. The gymnasts of the National Team achieved superior marks in 33.3% of the tests and 83.3% of the gymnasts of our sample did not present explosive power asymmetries. We conclude that the gymnasts of the National Team did not show the expected superiority in the tests, and the most of gymnasts presented a harmonious development of explosive power for both lower limbs, since they did not show functional asymmetries.

  7. Power optimization of digital baseband WCDMA receiver components on algorithmic and architectural level

    Directory of Open Access Journals (Sweden)

    M. Schämann

    2008-05-01

    Full Text Available High data rates combined with high mobility represent a challenge for the design of cellular devices. Advanced algorithms are required which result in higher complexity, more chip area and increased power consumption. However, this contrasts to the limited power supply of mobile devices.

    This presentation discusses the application of an HSDPA receiver which has been optimized regarding power consumption with the focus on the algorithmic and architectural level. On algorithmic level the Rake combiner, Prefilter-Rake equalizer and MMSE equalizer are compared regarding their BER performance. Both equalizer approaches provide a significant increase of performance for high data rates compared to the Rake combiner which is commonly used for lower data rates. For both equalizer approaches several adaptive algorithms are available which differ in complexity and convergence properties. To identify the algorithm which achieves the required performance with the lowest power consumption the algorithms have been investigated using SystemC models regarding their performance and arithmetic complexity. Additionally, for the Prefilter Rake equalizer the power estimations of a modified Griffith (LMS and a Levinson (RLS algorithm have been compared with the tool ORINOCO supplied by ChipVision. The accuracy of this tool has been verified with a scalable architecture of the UMTS channel estimation described both in SystemC and VHDL targeting a 130 nm CMOS standard cell library.

    An architecture combining all three approaches combined with an adaptive control unit is presented. The control unit monitors the current condition of the propagation channel and adjusts parameters for the receiver like filter size and oversampling ratio to minimize the power consumption while maintaining the required performance. The optimization strategies result in a reduction of the number of arithmetic operations up to 70% for single components which leads to an

  8. Habit, custom, and power: a multi-level theory of population health.

    Science.gov (United States)

    Zimmerman, Frederick J

    2013-03-01

    In multi-level theory, individual behavior flows from cognitive habits, either directly through social referencing, rules of thumb, or automatic behaviors; or indirectly through the shaping of rationality itself by framing or heuristics. Although behavior does not arise from individually rational optimization, it generally appears to be rational, because the cognitive habits that guide behavior evolve toward optimality. However, power imbalances shaped by particular social, political, and economic structures can distort this evolution, leading to individual behavior that fails to maximize individual or social well-being. Replacing the dominant rational-choice paradigm with a multi-level theoretical paradigm involving habit, custom, and power will enable public health to engage in rigorous new areas of research.

  9. Application of PSA to Assess the Safety Level of Nuclear Power Plants

    International Nuclear Information System (INIS)

    This paper reviews the application of PSA in German nuclear power plant regulation. From a fundamental point of view, it has to be mentioned that as stipulated in the corresponding requirements, regulatory decision making in Germany is primarily based on deterministic analyses and evaluations. Therefore, PSA is not used as a stand alone but as a supplementary basis. In this context PSA has developed a valuable tool with continuously growing importance. Level 1+ PSAs are now elaborated for all German nuclear power plants in operation, most of them are already reviewed by the competent supervisory authority and its experts. Current research activities on the federal level primarily concentrate on the further development of the methodology in the areas human factor, common cause failures, accident management measures and reduction of uncertainties in methods and data. (author)

  10. Modelling and measurement of the absolute level of power radiated by antenna integrated THz UTC photodiodes.

    Science.gov (United States)

    Natrella, Michele; Liu, Chin-Pang; Graham, Chris; van Dijk, Frederic; Liu, Huiyun; Renaud, Cyril C; Seeds, Alwyn J

    2016-05-30

    We determine the output impedance of uni-travelling carrier (UTC) photodiodes at frequencies up to 400 GHz by performing, for the first time, 3D full-wave modelling of detailed UTC photodiode structures. In addition, we demonstrate the importance of the UTC impedance evaluation, by using it in the prediction of the absolute power radiated by an antenna integrated UTC, over a broad frequency range and confirming the predictions by experimental measurements up to 185 GHz. This is done by means of 3D full-wave modelling and is only possible since the source (UTC) to antenna impedance match is properly taken into account. We also show that, when the UTC-to-antenna coupling efficiency is modelled using the classical junction-capacitance/series-resistance concept, calculated and measured levels of absolute radiated power are in substantial disagreement, and the maximum radiated power is overestimated by a factor of almost 7 dB. The ability to calculate the absolute emitted power correctly enables the radiated power to be maximised through optimisation of the UTC-to-antenna impedance match.

  11. Modelling and measurement of the absolute level of power radiated by antenna integrated THz UTC photodiodes.

    Science.gov (United States)

    Natrella, Michele; Liu, Chin-Pang; Graham, Chris; van Dijk, Frederic; Liu, Huiyun; Renaud, Cyril C; Seeds, Alwyn J

    2016-05-30

    We determine the output impedance of uni-travelling carrier (UTC) photodiodes at frequencies up to 400 GHz by performing, for the first time, 3D full-wave modelling of detailed UTC photodiode structures. In addition, we demonstrate the importance of the UTC impedance evaluation, by using it in the prediction of the absolute power radiated by an antenna integrated UTC, over a broad frequency range and confirming the predictions by experimental measurements up to 185 GHz. This is done by means of 3D full-wave modelling and is only possible since the source (UTC) to antenna impedance match is properly taken into account. We also show that, when the UTC-to-antenna coupling efficiency is modelled using the classical junction-capacitance/series-resistance concept, calculated and measured levels of absolute radiated power are in substantial disagreement, and the maximum radiated power is overestimated by a factor of almost 7 dB. The ability to calculate the absolute emitted power correctly enables the radiated power to be maximised through optimisation of the UTC-to-antenna impedance match. PMID:27410104

  12. Quantitative Model and Metrics of Electrical Grids’ Resilience Evaluated at a Power Distribution Level

    Directory of Open Access Journals (Sweden)

    Alexis Kwasinski

    2016-02-01

    Full Text Available This paper presents a framework to systematically measure and assess power grids’ resilience with a focus on performance as perceived by customers at the power distribution level. The proposed framework considers an analogous measure of availability as a basic metric for resilience and defines other key resilience-related concepts and metrics, such as resistance and brittleness. This framework also provides a measurement for the degree of functional dependency of loads on power grids and demonstrates how the concepts of resilience and dependency are inherently related. It also discusses the implications of considering human-centered processes as fundamental constituting components of infrastructure systems. Thanks to its quantitative nature, the proposed resilience framework enables the creation of tools to evaluate power grids’ performance as a lifeline and to assess the effects of plans for optimal electrical power infrastructure deployment and operation. The discussion is supported by practical examples and empirical records from field damage assessments conducted after recent notable natural disasters.

  13. A Transformer-less Partial Power Boost Converter for PV Applications Using a Three-Level Switching Cell

    Energy Technology Data Exchange (ETDEWEB)

    Agamy, Mohammed; Harfman-Todorovic, Maja; Elasser, Ahmed; Essakiappan, Somasundaram

    2013-03-01

    Photovoltaic architectures with distributed power electronics provide many advantages in terms of energy yield as well as system level optimization. As the power level of the solar farm increases it becomes more beneficial to increase the dc collection network voltage, which requires the use of power devices with higher voltage ratings, and thus making the design of efficient, low cost, distributed power converters more challenging. In this paper a simple partial power converter topology is proposed. The topology is implemented using a three-level switching cell, which allows the use of semiconductor devices with lower voltage rating; thus improving design and performance and reducing converter cost. This makes the converters suitable for use for medium to high power applications where dc-link voltages of 600V~1kV may be needed without the need for high voltage devices. Converter operation and experimental results are presented for two partial power circuit variants using three-level switching cells.

  14. A Polymer Optical Fiber Fuel Level Sensor: Application to Paramotoring and Powered Paragliding

    Directory of Open Access Journals (Sweden)

    David Sánchez Montero

    2012-05-01

    Full Text Available A low-cost intensity-based polymer optical fiber (POF sensor for fuel level measurements in paramotoring and powered paragliding is presented, exploiting the advantages of the optical fiber sensing technology. Experimental results demonstrate that the best option can be performed by stripping the fiber at the desired discrete points to measure the fuel level as well as with a gauge-shape fiber bending. The prototype has a good linearity, better than 4% full scale (F.S., and sensitivity around 0.5 V per bend are obtained. Hysteresis due to residual fluid at the sensing points is found to be less than 9% F.S.

  15. Processing of low-level and intermediate-level radioactive wastes from the nuclear power plant Muehleberg at Mol

    International Nuclear Information System (INIS)

    Between October 1986 and April 1987 two contracts were concluded between the nuclear power plant Muehleberg and the German firm Transnuklear GmbH for the processing of low-level and intermediate-level radioactive wastes from Muehleberg in the incineration facility at Mol in Belgium. In the contracts, transport of the wastes to Mol and back was included. According to the contracts the maximum admissible surface dose rate of the containers enclosing the wastes was 3000 mR/h. The actual maximum value of the surface dose rate was 1800 mR/h. On January 8, 1988, Swiss press published a statement to the effect that those wastes having a surface dose rate of more than 200 mR/h cannot be processed at Mol and must be transported back to Switzerland. Three representatives of Muehleberg visited Mol to discuss the conflicting information. The result of their inquiries was that the processing and transport of foreign wastes at Mol are currently suspended due to the irregularities associated with Transnuklear. Neither the safety nor the operation of the Muehleberg facility are jeopardized through the incident

  16. ENERGY EFFICIENT FLOW AND LEVEL CONTROL IN A HYDRO POWER PLANT USING FUZZY LOGIC

    Directory of Open Access Journals (Sweden)

    A. Selwin Mich Priyadharson

    2014-01-01

    Full Text Available The main objective and an innovative design of this work is to improve the energy efficiency by controlling the variables flow and level in a hydroelectric power plant using Programmable Logic Control (PLC-Human Machine Interface (HMI and fuzzy logic approach. This project will focus on design and development of flow and level controller for small scale hydro generating units by implementing gate control based on PLC-HMI and Fuzzy Logic Control (FLC. So far there is no other better performing control scheme, with uncomplicated approach, in order to match and satisfy the dynamic changes in load demand. In this project, FLC will be applied to flow and level control for small scale hydro generating units is proposed. A lab scale experimental setup is made-up as prototype model for flow and level control and simulation outputs were achieved, using PLC-HMI based fuzzy controller scheme. The hardware set up is designed with 5 stages in the tank 1 and 2 stages in the tank 2. Based on the outputs of the level sensors from tanks 1 and 2, the ladder logic will perform. B&R Industrial Automation PLC inbuilt with 24 digital inputs and provides 16 potential free outputs is used to perform control action. Finally, the performance of the proposed scheme is evaluated by simulation results by comparing with conventional controllers output using the data collected from the hydroelectric power plant. The merits of the proposed Fuzzy scheme over the conventional method are spotlighted.

  17. Power Quality Improvement at Distribution Level for Grid Connected Renewable Energy Sources

    Directory of Open Access Journals (Sweden)

    S. Syed Ahmed

    2014-09-01

    Full Text Available The non-linear load current harmonics may result in voltage harmonics and can create a serious PQ problem in the power system network. Active power filters (APF are extensively used to compensate the load current harmonics and load unbalance at distribution level. This results in an additional hardware cost. However, in this project it has incorporated the features of APF in the conventional inverter interfacing renewable with the grid, without any additional hardware cost. Here, the main idea is the maximum utilization of inverter rating which is most of the time underutilized due to intermittent nature of RES. The grid-interfacing inverter can effectively be utilized to perform the four important functions they are to transfer active power harvested from the renewable resources (wind, solar, etc., load reactive power demand support, current harmonics compensation at PCC and current unbalance and neutral current compensation in case of 3-phase 4-wire system. Moreover, with adequate control of grid-interfacing inverter, all the four objectives can be accomplished either individually or simultaneously. The PQ constraints at the PCC can therefore be strictly maintained within the utility standards without additional hardware cost. With such a control, the combination of grid-interfacing inverter and the 3-phase 4-wire linear/non-linear unbalanced load at point of common coupling appears as balanced linear load to the grid. This new control concept is demonstrated with extensive MATLAB/Simulink simulation studies

  18. A detector for monitoring the onset of cavitation during therapy-level measurements of ultrasonic power

    Science.gov (United States)

    Hodnett, M.; Zeqiri, B.

    2004-01-01

    Acoustic cavitation occurring in the water path between a transducer and the target of a radiation force balance can provide a significant source of error during measurements of ultrasonic power. These problems can be particularly acute at physiotherapy levels (>1 W), and low frequencies (leq 1 MHz). The cavitating bubbles can absorb and scatter incident ultrasound, leading to an underestimate in the measured power. For these reasons, International Specification standards demand the use of degassed water. This imposes requirements that may actually be difficult to meet, for example, in the case of hospitals. Also, initially degassed water will rapidly re-gas, increasing the likelihood of cavitation occurring. For these reasons, NPL has developed a device that monitors acoustic emissions generated by bubble activity, for detecting the onset of cavitation during power measurements. A commercially available needle hydrophone is used to detect these emissions. The acoustic signals are then monitored using a Cavitation Detector (CD) unit, comprising an analogue electrical filter that may be tuned to detect frequency components generated by cavitating bubbles, and which provides an indication of when the measured level exceeds a pre-defined threshold. This paper describes studies to establish a suitable detection scheme, the principles of operation of the CD unit, and the performance tests carried out with a range of propagation media.

  19. Assessment of two-level heat pump installations’ power efficiency for heat supply systems

    Directory of Open Access Journals (Sweden)

    Аlla Е. Denysova

    2015-06-01

    Full Text Available The problem of energy saving becomes one of the most important in power engineering. It is caused by exhaustion of world reserves in hydrocarbon fuel, such as gas, oil and coal representing sources of traditional heat supply. Conventional sources has essential shortcomings: low power, ecological and economic efficiencies, that can be eliminated by using alternative methods of power supply, like the considered one: low-temperature natural heat of ground waters of on the basis of heat pump installations application. The heat supply system considered provides an effective use of two-level heat pump installation operating as heat source the Odessa city ground waters during the lowest ambient temperature period. Proposed is a calculation method of heat pump installations on the basis of geothermal heat supply. Calculated are the values of electric energy consumption N by the compressors’ drive, and the heat supply system transformation coefficient µ for a source of geothermal heat from ground waters of Odessa city allowing to estimate efficiency of two-level heat pump installations.

  20. Islanding the power grid on the transmission level: less connections for more security

    Science.gov (United States)

    Mureddu, Mario; Caldarelli, Guido; Damiano, Alfonso; Scala, Antonio; Meyer-Ortmanns, Hildegard

    2016-01-01

    Islanding is known as a management procedure of the power system that is implemented at the distribution level to preserve sensible loads from outages and to guarantee the continuity in electricity supply, when a high amount of distributed generation occurs. In this paper we study islanding on the level of the transmission grid and shall show that it is a suitable measure to enhance energy security and grid resilience. We consider the German and Italian transmission grids. We remove links either randomly to mimic random failure events, or according to a topological characteristic, their so-called betweenness centrality, to mimic an intentional attack and test whether the resulting fragments are self-sustainable. We test this option via the tool of optimized DC power flow equations. When transmission lines are removed according to their betweenness centrality, the resulting islands have a higher chance of being dynamically self-sustainable than for a random removal. Less connections may even increase the grid’s stability. These facts should be taken into account in the design of future power grids. PMID:27713509

  1. Islanding the power grid on the transmission level: less connections for more security

    Science.gov (United States)

    Mureddu, Mario; Caldarelli, Guido; Damiano, Alfonso; Scala, Antonio; Meyer-Ortmanns, Hildegard

    2016-10-01

    Islanding is known as a management procedure of the power system that is implemented at the distribution level to preserve sensible loads from outages and to guarantee the continuity in electricity supply, when a high amount of distributed generation occurs. In this paper we study islanding on the level of the transmission grid and shall show that it is a suitable measure to enhance energy security and grid resilience. We consider the German and Italian transmission grids. We remove links either randomly to mimic random failure events, or according to a topological characteristic, their so-called betweenness centrality, to mimic an intentional attack and test whether the resulting fragments are self-sustainable. We test this option via the tool of optimized DC power flow equations. When transmission lines are removed according to their betweenness centrality, the resulting islands have a higher chance of being dynamically self-sustainable than for a random removal. Less connections may even increase the grid’s stability. These facts should be taken into account in the design of future power grids.

  2. Alterative LEU designs for the FRM-II with power levels of 20-22 MW.

    Energy Technology Data Exchange (ETDEWEB)

    Hanan, N. A.; Smith, R. S.; Matos, J. E.

    1999-09-27

    Alternative LEU Designs for the FRM-II have been developed by the RERTR Program at Argonne National Laboratory (ANL) at the request of an FRM-II Expert Group established by the German Federal Government in January 1999 to evaluate the options for using LEU fuel instead of HEU fuel in cores with power levels of 20 MW. The ANL designs would use the same building structure and maintain as many of the HEU design features as practical. The range of potential LEU fuels was expanded from previous studies to include already-tested silicide fuels with uranium densities up to 6.7 g/cm{sup 3} and the new U-Mo fuels that show excellent prospects for achieving uranium densities in the 8-9 g/cm{sup 3} range. For each of the LEU cores; the design parameters were chosen to match the 50 day cycle length of the HEU core and to maximize the thermal neutron flux in the Cold Neutron Source and beam tubes. The studies concluded that an LEU core with a diameter of about 29 cm instead of 24 cm in HEU design and operating at a power level of 20 MW would have thermal neutron fluxes that are 0.85 times that of the HEU design at the center of the Cold Neutron Source. With a potential future upgrade to a power of 22 MW, this ratio would increase to 0.93.

  3. A detector for monitoring the onset of cavitation during therapy-level measurements of ultrasonic power

    Energy Technology Data Exchange (ETDEWEB)

    Hodnett, M; Zeqiri, B [National Physical Laboratory, Queens Road, Teddington, Middlesex, TW11 0LW (United Kingdom)

    2004-01-01

    Acoustic cavitation occurring in the water path between a transducer and the target of a radiation force balance can provide a significant source of error during measurements of ultrasonic power. These problems can be particularly acute at physiotherapy levels (>1 W), and low frequencies ({<=} 1 MHz). The cavitating bubbles can absorb and scatter incident ultrasound, leading to an underestimate in the measured power. For these reasons, International Specification standards demand the use of degassed water. This imposes requirements that may actually be difficult to meet, for example, in the case of hospitals. Also, initially degassed water will rapidly re-gas, increasing the likelihood of cavitation occurring. For these reasons, NPL has developed a device that monitors acoustic emissions generated by bubble activity, for detecting the onset of cavitation during power measurements. A commercially available needle hydrophone is used to detect these emissions. The acoustic signals are then monitored using a Cavitation Detector (CD) unit, comprising an analogue electrical filter that may be tuned to detect frequency components generated by cavitating bubbles, and which provides an indication of when the measured level exceeds a pre-defined threshold. This paper describes studies to establish a suitable detection scheme, the principles of operation of the CD unit, and the performance tests carried out with a range of propagation media.

  4. Global Sea Level Stabilization-Sand Dune Fixation: A Solar-powered Sahara Seawater Textile Pipeline

    CERN Document Server

    Badescu, Viorel; Bolonkin, Alexander A

    2007-01-01

    Could anthropogenic saturation with pumped seawater of the porous ground of active sand dune fields in major deserts (e.g., the westernmost Sahara) cause a beneficial reduction of global sea level? Seawater extraction from the ocean, and its deposition on deserted sand dune fields in Mauritania and elsewhere via a Solar-powered Seawater Textile Pipeline (SSTP) can thwart the postulated future global sea level. Thus, Macro-engineering offers an additional cure for anticipated coastal change, driven by global sea level rise, that could supplement, or substitute for (1) stabilizing the shoreline with costly defensive public works (armoring macroprojects) and (2) permanent retreat from the existing shoreline (real and capital property abandonment). We propose Macro-engineering use tactical technologies that sculpt and vegetate barren near-coast sand dune fields with seawater, seawater that would otherwise, as commonly postulated, enlarge Earth seascape area! Our Macro-engineering speculation blends eremology with...

  5. Fault detection and diagnosis of the deaerator level control system in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyung Youn; Lee, Yoon Joon [Cheju National Univ., Cheju (Korea, Republic of)

    2004-02-01

    The deaerator of a power plant is one of feedwater heaters in the secondary system, and it is located above the feedwater pumps. The feedwater pumps take the water from the deaerator storage tank, and the Net Positive Suction Head(NPSH) should always be ensured. To secure the sufficient NPSH, the deaerator tank is equipped with the level control system of which level sensors are critical items. And it is necessary to ascertain the sensor state on-line. For this, a model-based Fault Detection and Diagnosis(FDD) is introduced in this study. The dynamic control model is formulated from the relation of input-output flow rates and liquid-level of the deaerator storage tank. Then an adaptive state estimator is designed for the fault detection and diagnosis of sensors. The performance and effectiveness of the proposed FDD scheme are evaluated by applying the operation data of Yonggwang Units 3 and 4.

  6. 75 FR 24755 - DTE ENERGY; Enrico Fermi Atomic Power Plant Unit 1; Exemption From Certain Low-Level Waste...

    Science.gov (United States)

    2010-05-05

    ... COMMISSION DTE ENERGY; Enrico Fermi Atomic Power Plant Unit 1; Exemption From Certain Low-Level Waste... offsite low-level radioactive waste disposal sites. Experience at other decommissioning nuclear power... radioactive waste shipment times from the Fermi-1 site to the disposal site. ] 3.0 Discussion The...

  7. Modeling of Busbars in High Power Neutral Point Clamped Three-Level Inverters

    Institute of Scientific and Technical Information of China (English)

    YI Rung; ZHAO Zhengming; ZHONG Yulin

    2008-01-01

    The busbars in high power neutral point clamped three-level inverters are modeled using the Maxwell Q3D Extractor software, which is based on the partial element equivalent circuits method. The equivalent circuits of the busbars and devices model are simulated in the electric simulator PSIM to analyze the effects of the parasitic inductance on the switching characteristics of the integrated gate commutatedthyristor (IGCT) in different topology positions. The simulation results agree well with the measured imped-ance analyzer results and the IGCT test results, which proves the effectiveness of the modeling method for the large, complex busbars.

  8. The tensor analyzing power Asub(yy) near s-wave levels

    International Nuclear Information System (INIS)

    In the neighborhood of an isolated resonance induced by s-wave particles, the component Asub(yy)(theta) of the tensor analyzing power is independent of the reaction angle theta. The constant value of Asub(yy)(theta) is a function of the level spin J and of the (l',s') configuration in the exit channel of the resonant amplitude. The use of this fact as a diagnostic tool in an analysis of the process is discussed and demonstrated with data available. It is also pointed out that efficient polarimeters can be constructed, which measure the quantity Asub(yy). (Auth.)

  9. Radioactivity level of the ambient environment of Anren bone-coal power station

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The radioactivity level of the ambient environment of Anren Bonc-coalPower Station (BCPS) was investigated systematically. The γ radiation dose ratelevel in the environment, the content of 238U and 226Ra in the ambient soil and thefarmland in the direction of downwind, the concentrations of 238U, 232Th, 226Ra, 40Kand 222Rn, as well as α potential energy in air, and the concentrations of natural Uand Th in effluent are all higher than the corresponding values of the reference site.The additional annual effective dose equivalent to the residents living in the housesmade of bone-coal cinder brick is 2.7mSv.

  10. Computational analysis of the curvature distribution and power losses of metal strip in tension levellers

    International Nuclear Information System (INIS)

    Tension levelling is employed in strip processing lines to minimise residual stresses resp. to improve the strip flatness by inducing small elasto-plastic deformations. To improve the design of such machines, precise calculation models are essential to reliably predict tension losses due to plastic dissipation, power requirements of the driven bridle rolls (located upstream and downstream), reaction forces on levelling rolls as well as strains and stresses in the strip. FEM (Finite Element Method) simulations of the tension levelling process (based on Updated Lagrangian concepts) yield high computational costs due to the necessity of very fine meshes as well as due to the severely non-linear characteristics of contact, material and geometry. In an evaluation process of hierarchical models (models with different modeling levels), the reliability of both 3D and 2D modelling concepts (based on continuum and structural elements) was proved by extensive analyses as well as consistency checks against measurement data from an industrial tension leveller. To exploit the potential of computational cost savings, a customised modelling approach based on the principle of virtual work has been elaborated, which yields a drastic reduction of degrees of freedom compared to simulations by utilising commercial FEM-packages.

  11. Modeling Photovoltaic Module-Level Power Electronics in the System Advisor Model; NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-07-01

    Module-level power electronics, such as DC power optimizers, microinverters, and those found in AC modules, are increasing in popularity in smaller-scale photovoltaic (PV) systems as their prices continue to decline. Therefore, it is important to provide PV modelers with guidelines about how to model these distributed power electronics appropriately in PV modeling software. This paper extends the work completed at NREL that provided recommendations to model the performance of distributed power electronics in NREL’s popular PVWatts calculator [1], to provide similar guidelines for modeling these technologies in NREL's more complex System Advisor Model (SAM). Module-level power electronics - such as DC power optimizers, microinverters, and those found in AC modules-- are increasing in popularity in smaller-scale photovoltaic (PV) systems as their prices continue to decline. Therefore, it is important to provide PV modelers with guidelines about how to model these distributed power electronics appropriately in PV modeling software.

  12. Study and Analysis of a Natural Reference Frame Current Controller for a Multi-Level H-Bridge Power Converter

    DEFF Research Database (Denmark)

    Ciobotaru, Mihai; Iov, Florin; Zanchetta, P.;

    2008-01-01

    To pave the way to a sustainable energy future based on a larger share of Distributed Generation (DG), there is a clear need to prepare the European electricity system for the large-scale integration of both renewable and other distributed energy sources. Advanced power electronic converters for DG...... will be needed in order to control the power flow and to ensure proper and secure operation of this future grid with an increased level of renewable power. These power converters must be able to provide intelligent power management as well as ancillary services. This paper presents an analysis of the natural...... reference frame controller, based on proportional-resonant (PR) technique, for a multi-level H-bridge power converter for Universal and Flexible Power Management in Future Electricity Network. The proposed method is tested in terms of harmonic content in the Point of Common Coupling (PCC), voltage...

  13. What day-ahead reserves are needed in electric grids with high levels of wind power?

    Science.gov (United States)

    Mauch, Brandon; Apt, Jay; Carvalho, Pedro M. S.; Jaramillo, Paulina

    2013-09-01

    Day-ahead load and wind power forecasts provide useful information for operational decision making, but they are imperfect and forecast errors must be offset with operational reserves and balancing of (real time) energy. Procurement of these reserves is of great operational and financial importance in integrating large-scale wind power. We present a probabilistic method to determine net load forecast uncertainty for day-ahead wind and load forecasts. Our analysis uses data from two different electric grids in the US with similar levels of installed wind capacity but with large differences in wind and load forecast accuracy, due to geographic characteristics. We demonstrate that the day-ahead capacity requirements can be computed based on forecasts of wind and load. For 95% day-ahead reliability, this required capacity ranges from 2100 to 5700 MW for ERCOT, and 1900 to 4500 MW for MISO (with 10 GW of installed wind capacity), depending on the wind and load forecast values. We also show that for each MW of additional wind power capacity for ERCOT, 0.16-0.30 MW of dispatchable capacity will be used to compensate for wind uncertainty based on day-ahead forecasts. For MISO (with its more accurate forecasts), the requirement is 0.07-0.13 MW of dispatchable capacity for each MW of additional wind capacity.

  14. Allowable Residual Contamination Levels in soil for decommissioning the Shippingport Atomic Power Station site

    International Nuclear Information System (INIS)

    As part of decommissioning the Shippingport Atomic Power Station, a fundamental concern is the determination of Allowable Residual Contamination Levels (ARCL) for radionuclides in the soil at the site. The ARCL method described in this report is based on a scenario/exposure-pathway analysis and compliance with an annual dose limit for unrestricted use of the land after decommissioning. In addition to naturally occurring radionuclides and fallout from weapons testing, soil contamination could potentially come from five other sources. These include operation of the Shippingport Station as a pressurized water reactor, operations of the Shippingport Station as a light-water breeder, operation of the nearby Beaver Valley reactors, releases during decommissioning, and operation of other nearby industries, including the Bruce-Mansfield coal-fired power plants. ARCL values are presented for 29 individual radionculides and a worksheet is provided so that ARCL values can be determined for any mixture of the individual radionuclides for any annual dose limit selected. In addition, a worksheet is provided for calculating present time soil concentration value that will decay to the ARCL values after any selected period of time, such as would occur during a period of restricted access. The ARCL results are presented for both unconfined (surface) and confined (subsurface) soil contamination. The ARCL method and results described in this report provide a flexible means of determining unrestricted-use site release conditions after decommissioning the Shippingport Atomic Power Station

  15. Evaluating the level and nature of sustainable development for a geothermal power plant

    International Nuclear Information System (INIS)

    The paper provides for an evaluation of the potential level and nature of sustainable development of the Sabalan geothermal power plant in NW Iran, to be operational in 2011. The paper achieves this by applying a mathematical model of sustainable development developed by the author (re: Phillips), in respect to the Environmental Impact Assessment (EIA) conducted by Yousefi et al. using the Rapid Impact Assessment Matrix (RIAM) methodology (re: Pastakia; Pastakia and Jensen). Using a model application methodology developed for the RIAM, the results indicated that the nature of sustainable development for Sabalan was considered to be very weak (S = 0.063). This was due to the imbalance between negative environmental impacts and positive socio-economic impacts deriving from the project. Further, when placed into context with a similar set of results obtained from the EIA of the Tuzla geothermal power plant by Baba also using the RIAM methodology, then the similarities between the results obtained raises some legimate questions as to the sustainable development credentials of geothermal power production. (author)

  16. What day-ahead reserves are needed in electric grids with high levels of wind power?

    International Nuclear Information System (INIS)

    Day-ahead load and wind power forecasts provide useful information for operational decision making, but they are imperfect and forecast errors must be offset with operational reserves and balancing of (real time) energy. Procurement of these reserves is of great operational and financial importance in integrating large-scale wind power. We present a probabilistic method to determine net load forecast uncertainty for day-ahead wind and load forecasts. Our analysis uses data from two different electric grids in the US with similar levels of installed wind capacity but with large differences in wind and load forecast accuracy, due to geographic characteristics. We demonstrate that the day-ahead capacity requirements can be computed based on forecasts of wind and load. For 95% day-ahead reliability, this required capacity ranges from 2100 to 5700 MW for ERCOT, and 1900 to 4500 MW for MISO (with 10 GW of installed wind capacity), depending on the wind and load forecast values. We also show that for each MW of additional wind power capacity for ERCOT, 0.16–0.30 MW of dispatchable capacity will be used to compensate for wind uncertainty based on day-ahead forecasts. For MISO (with its more accurate forecasts), the requirement is 0.07–0.13 MW of dispatchable capacity for each MW of additional wind capacity. (letter)

  17. Design of LCL-Filter Based Three-level Active Power Filter

    Directory of Open Access Journals (Sweden)

    Shilan Chen

    2013-07-01

    Full Text Available This paper proposes an improved design of LCL-Filters for Three-Level Shunt Active power filters (APF. Available design principles are presented to achieve high compensation bandwidth and low switching frequency current. Then, affecitons of different parameters are taken into consideration of constraints on LCL-Filter design with detail analysis of ripple current. A simple and practical design procedure of LCL-Filter for Three-Level APF is subsequently proposed. The first step is to choose the resonant frequency of LCL-Filter according to the highest order harmonic needed to be compensated. Then it is aim to optimize the parameters of the LCL-Filter based on the design principles and constraints. The simulation results verify the effectiveness of the proposed method.

  18. Potential for de-regulated disposal of very low level wastes from nuclear power plants

    International Nuclear Information System (INIS)

    The purpose of the study discussed in this paper was to review the characteristics of low level waste streams generated in commercial nuclear power facilities to determine which may be suitable for disposal by methods other than transfer to a facility licensed by the Nuclear Regulatory Commission (NRC) and to evaluate the benefits, risks, and costs of exempting such very low level wastes (VLW) from the disposal requirements of 10 CFR Part 61. Of course, wastes that no longer require regulation of their radiological properties are still subject to the regulatory controls - federal, state, or local - that affect non-radioactive wastes of similar chemical and physical properties and similar origins. This study addressed radiological aspects only, and assumed, in its evaluations, that the wastes can and will be disposed of in accordance with all other applicable requirements. 4 references, 1 figure, 6 tables

  19. Smart energy management and low-power design of sensor and actuator nodes on algorithmic level for self-powered sensorial materials and robotics

    Science.gov (United States)

    Bosse, Stefan; Behrmann, Thomas

    2011-06-01

    We propose and demonstrate a design methodology for embedded systems satisfying low power requirements suitable for self-powered sensor and actuator nodes. This design methodology focuses on 1. smart energy management at runtime and 2. application-specific System-On- Chip (SoC) design at design time, contributing to low-power systems on both algorithmic and technology level. Smart energy management is performed spatially at runtime by a behaviour-based or state-action-driven selection from a set of different (implemented) algorithms classified by their demand of computation power, and temporally by varying data processing rates. It can be shown that power/energy consumption of an application-specific SoC design depends strongly on computation complexity. Signal and control processing is modelled on abstract level using signal flow diagrams. These signal flow graphs are mapped to Petri Nets to enable direct high-level synthesis of digital SoC circuits using a multi-process architecture with the Communicating-Sequential-Process model on execution level. Power analysis using simulation techniques on gatelevel provides input for the algorithmic selection during runtime of the system, leading to a closed-loop design flow. Additionally, the signal-flow approach enables power management by varying the signal flow and data processing rates depending on actual energy consumption, estimated energy deposit, and required Quality-of-Service.

  20. Power

    OpenAIRE

    Samuel Bowles; Herbert Gintis

    2007-01-01

    We consider the exercise of power in competitive markets for goods, labour and credit. We offer a definition of power and show that if contracts are incomplete it may be exercised either in Pareto-improving ways or to the disadvantage of those without power. Contrasting conceptions of power including bargaining power, market power, and consumer sovereignty are considered. Because the exercise of power may alter prices and other aspects of exchanges, abstracting from power may miss essential a...

  1. Comparison of p53 levels in lymphocytes and in blood plasma of nuclear power plant workers

    International Nuclear Information System (INIS)

    p53 levels were assessed in lymphocytes and in blood plasma of workers from two Czech nuclear power plants (NPP): 114 subjects working in Temelin and 108 subjects working in Dukovany. Ionizing radiation (IR) exposure data were available for 64 and 59 subjects working in the monitored zones from the NPP in Temelin and Dukovany, respectively. The short-term doses of IR for these subjects were 0.01 and 0.12 mSv, and the long-term doses were 0.46 and 5.68 mSv, in the Temelin and Dukovany NPP, respectively. As a control group, 46 subjects living in Ceske Budejovice, a city nearby the Temelin NPP, were analyzed. The concentration of p53 in lymphocytes was significantly higher in workers from the monitored zone in the Dukovany NPP (median value 6.4 pg/μg protein, P < 0.001) than in workers from the Temelin NPP (3.2 pg/μg) as well as in the control group (3.5 pg/μg). In contrast, plasma levels of p53 were comparable in the control group (median value 116 pg/ml plasma) and workers from the monitored zone of Dukovany NPP (102 pg/ml), but lower in workers from Temelin NPP (5 pg/ml). Other factors affecting p53 levels were studied. Smoking resulted in increased p53 lymphocyte levels. The effect of polymorphisms in metabolic and DNA repair genes on p53 levels was analyzed. The correlation was found between p53 levels in lymphocytes and p53 codon 72 polymorphism in subjects working in NPPs, but not in the control group. The results of measurement p53 levels in lymphocytes suggest that this biomarker could reflect the short-term as well as long-term effects of low doses IR. Its impact on human health should be further explored

  2. Trending of low level events and near misses to enhance safety performance in nuclear power plants

    International Nuclear Information System (INIS)

    The IAEA Safety Fundamentals publication, Safety of Nuclear Installations, Safety Series No. 110, states the need for operating organizations to establish a programme for the collection and analysis of operating experience in nuclear power plants. Such a programme ensures that operating experience is analysed, events important to safety are reviewed in depth, and lessons learned are disseminated to the staff of the organization and to relevant national and international organizations. As a result of the effort to enhance safety in operating organizations, incidents are progressively decreasing in number and significance. This means that in accordance with international reporting requirements the amount of collected data becomes less sufficient to draw meaningful statistical conclusions. This is where the collection and trend analysis of low level events and near misses can prove to be very useful. These trends can show which of the safety barriers are weak or failing more frequently. Evaluation and trending of low level events and near misses will help to prevent major incidents because latent weaknesses have been identified and corrective actions taken to prevent recurrence. This leads to improved safety and production. Low level events and near misses, which may reach several thousand per reactor operating year, need to be treated by the organizations as learning opportunities. A system for capturing these low level events and near misses truly needs to be an organization-wide system in which all levels of the organization, including contractors, participate. It is desirable that the overall operational experience feedback (OEF) process should integrate the lessons learned and the associated data from significant events with those of lower level events and near misses. To be able to effectively implement a process dealing with low level events and near misses, it is necessary that the organization have a well established OEF process for significant events

  3. Design and Analysis of Multi Level D-STATCOM to Improve the Power Quality

    OpenAIRE

    Dinesh. Badavath,; Mr. T. Subramanya Sastry

    2014-01-01

    In the last decade, the electrical power quality issue has been the main concern of the power companies. Power quality is defined as the index which both the delivery and consumption of electric power affect on the performance of electrical apparatus. From a customer point of view, a power quality problem can be defined as any problem is manifested on voltage, current, or frequency deviation that results in power failure. The power electronics progressive, especially in flexib...

  4. Experimental analysis of flexibility change with different levels of power reduction by demand response activation on thermostat controlled loads

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam; Marinelli, Mattia; Hu, Junjie;

    2016-01-01

    This paper studies the flexibility available with thermostatically controlled loads (TCLs) to provide power system services by demand response (DR) activation. Although the DR activation on TCLs can provide power system ancillary services, it is important to know how long such services can...... be provided for when different levels of power reduction are imposed. The flexibility change with different levels of power reduction is tested experimentally with domestic fridges used by real customers with unknown user interaction. The investigation quantifies the flexibility of household fridges...

  5. Application of Backstepping to the Virtual Flux Direct Power Control of Five-Level Three-Phase Shunt Active Power Filter

    Directory of Open Access Journals (Sweden)

    Bouzidi Mansour

    2014-03-01

    Full Text Available This paper proposes a virtual flux direct power control-space vector modulation combined with backstepping control for three-phase five-level neutral point clamped shunt active power filter. The main goal of the proposed active filtering system is to eliminate the unwanted harmonics and compensate fundamental reactive power drawn from the nonlinear loads. In this study, the voltage-balancing control of four split dc capacitors of the five-level active filter is achieved using five-level space vector modulation with balancing strategy based on the effective use of the redundant switching states of the inverter voltage vectors. The obtained results showed that, the proposed multilevel shunt active power filter with backstepping control can produce a sinusoidal supply current with low harmonic distortion and in phase with the line voltage.

  6. Development Efforts Expanded in Ion Propulsion: Ion Thrusters Developed With Higher Power Levels

    Science.gov (United States)

    Patterson, Michael J.; Rawlin, Vincent K.; Sovey, James S.

    2003-01-01

    The NASA Glenn Research Center was the major contributor of 2-kW-class ion thruster technology to the Deep Space 1 mission, which was successfully completed in early 2002. Recently, NASA s Office of Space Science awarded approximately $21 million to Glenn to develop higher power xenon ion propulsion systems for large flagship missions such as outer planet explorers and sample return missions. The project, referred to as NASA's Evolutionary Xenon Thruster (NEXT), is a logical follow-on to the ion propulsion system demonstrated on Deep Space 1. The propulsion system power level for NEXT is expected to be as high as 25 kW, incorporating multiple ion thrusters, each capable of being throttled over a 1- to 6-kW power range. To date, engineering model thrusters have been developed, and performance and plume diagnostics are now being documented. The project team-Glenn, the Jet Propulsion Laboratory, General Dynamics, Boeing Electron Dynamic Devices, the Applied Physics Laboratory, the University of Michigan, and Colorado State University-is in the process of developing hardware for a ground demonstration of the NEXT propulsion system, which comprises a xenon feed system, controllers, multiple thrusters, and power processors. The development program also will include life assessments by tests and analyses, single-string tests of ion thrusters and power systems, and finally, multistring thruster system tests in calendar year 2005. In addition, NASA's Office of Space Science selected Glenn to lead the development of a 25-kW xenon thruster to enable NASA to conduct future missions to the outer planets of Jupiter and beyond, under the High Power Electric Propulsion (HiPEP) program. The development of a 100-kW-class ion propulsion system and power conversion systems are critical components to enable future nuclear-electric propulsion systems. In fiscal year 2003, a team composed of Glenn, the Boeing Company, General Dynamics, the Applied Physics Laboratory, the Naval Research

  7. A Battery-less Grid Connected Photovoltaic Power generation using Five-Level Common-Emitter Current-Source Inverter

    Directory of Open Access Journals (Sweden)

    Suroso Suroso

    2014-12-01

    Full Text Available Renewable power generation using photovoltaic is very interesting to be developed to deal with the problems of conventional energy sources and environmental issues. The photovoltaic power generation can operate both in stand-alone and grid-connected operations. This paper presents an application of the five-level common-emitter current-source inverter (CE-CSI for grid connected photovoltaic system without batteries as energy storage system. In the proposed system, the five-level CE-CSI works generating a sinusoidal output current from photovoltaic system to be injected into the power grid. The transformer is used in the system to step-down the grid voltage to meet the voltage level of the photovoltaic system, and also works as a galvanic insulation between the power grid and the inverter system. Two conditions of the power grid voltage, i.e. a pure sinusoidal and a distorted power grid, are tested through computer simulation using PSIM software. Furthermore, experimental test result of the five-level inverter is also presented. The test results show that the five-level CE-CSI works well injecting a sinusoidal current into the power grid with low harmonic contents, and with unity power factor operation. The results also show that the distorted grid voltage affects the harmonic contents of the current injected by the inverter.

  8. Low Level Event and Near Miss Process for Nuclear Power Plants: Best Practices

    International Nuclear Information System (INIS)

    The IAEA programme on the operational safety of nuclear power plants gives priority to the development and promotion of the proper use of IAEA safety standards through the provision of assistance to Member States in the application of safety standards, the performance of safety review missions and the conduct of training activities based on safety standards. A number of IAEA safety standards and nuclear safety publications discuss the processes that need to be put into place for the feedback and analysis of operating experience (OE) at nuclear power plants. These include: Fundamental Safety Principles (IAEA Safety Standards Series No. SF-1), Safety of Nuclear Power Plants: Commissioning and Operation (IAEA Safety Standards Series No. SSR-2/2), Application of the Management System for Facilities and Activities (IAEA Safety Standards Series No. GS-G-3.1) and A System for the Feedback of Experience from Events in Nuclear Installations (IAEA Safety Standards Series No. NS-G-2.11). Additionally, several IAEA TECDOCs cover many aspects of the establishment, conduct and continuous improvement of an OE programme at nuclear power plants, including the consideration of low level events (LLEs) and near misses (NMs). Although these IAEA safety standards and nuclear safety publications have been in existence for several years, 70 per cent of the IAEA Operational Safety Review Team (OSART) missions carried out at nuclear power plants between 2006 and 2010 identified weaknesses in the reporting and analysis process for LLEs and NMs. In fact, this has been one of the recurring issues most often identified in the area of OE during these missions. These weaknesses have been further confirmed by most of the IAEA Peer Review of the Operational Safety Performance Experience (PROSPER) missions that have been conducted to date. Finally, the IAEA International Nuclear Safety Group, in their report entitled Improving the International System for Operating Experience Feedback (INSAG-23

  9. Fourier power spectrum characteristics of face photographs: attractiveness perception depends on low-level image properties.

    Directory of Open Access Journals (Sweden)

    Claudia Menzel

    Full Text Available We investigated whether low-level processed image properties that are shared by natural scenes and artworks - but not veridical face photographs - affect the perception of facial attractiveness and age. Specifically, we considered the slope of the radially averaged Fourier power spectrum in a log-log plot. This slope is a measure of the distribution of special frequency power in an image. Images of natural scenes and artworks possess - compared to face images - a relatively shallow slope (i.e., increased high spatial frequency power. Since aesthetic perception might be based on the efficient processing of images with natural scene statistics, we assumed that the perception of facial attractiveness might also be affected by these properties. We calculated Fourier slope and other beauty-associated measurements in face images and correlated them with ratings of attractiveness and age of the depicted persons (Study 1. We found that Fourier slope - in contrast to the other tested image properties - did not predict attractiveness ratings when we controlled for age. In Study 2A, we overlaid face images with random-phase patterns with different statistics. Patterns with a slope similar to those in natural scenes and artworks resulted in lower attractiveness and higher age ratings. In Studies 2B and 2C, we directly manipulated the Fourier slope of face images and found that images with shallower slopes were rated as more attractive. Additionally, attractiveness of unaltered faces was affected by the Fourier slope of a random-phase background (Study 3. Faces in front of backgrounds with statistics similar to natural scenes and faces were rated as more attractive. We conclude that facial attractiveness ratings are affected by specific image properties. An explanation might be the efficient coding hypothesis.

  10. A General Framework for Power Analysis to Detect the Moderator Effects in Two- and Three-Level Cluster Randomized Trials

    Science.gov (United States)

    Dong, Nianbo; Spybrook, Jessaca; Kelcey, Ben

    2016-01-01

    The purpose of this study is to propose a general framework for power analyses to detect the moderator effects in two- and three-level cluster randomized trials (CRTs). The study specifically aims to: (1) develop the statistical formulations for calculating statistical power, minimum detectable effect size (MDES) and its confidence interval to…

  11. Levelized Cost of Energy Analysis of a Wind Power Generation System at Búrfell in Iceland

    Directory of Open Access Journals (Sweden)

    Birgir Freyr Ragnarsson

    2015-09-01

    Full Text Available Wind energy harnessing is a new energy production alternative in Iceland. Current installed wind power in Iceland sums to 1.8 MW, which in contrast is 0.1% of the country’s total electricity production. This article is dedicated to the exploration of the potential cost of wind energy production at Búrfell in the south of Iceland. A levelized cost of energy (LCOE approach was applied to the estimation of the potential cost. Weibull simulation is used to simulate wind data for calculations. A confirmation of the power law is done by comparing real data to calculated values. A modified Weibull simulation is verified by comparing results with actual on-site test wind turbines. A wind farm of 99MWis suggested for the site. Key results were the capacity factor (CF at Búrfell being 38.15% on average and that the LCOE for wind energy was estimated as 0.087–0.088 USD/kWh (assuming 10% weighted average cost of capital (WACC, which classifies Búrfell among the lowest LCOE sites for wind energy in Europe.

  12. On the Efficiency of a Two-Power-Level Flywheel-Based All-Electric Driveline

    Directory of Open Access Journals (Sweden)

    Hans Bernhoff

    2012-08-01

    Full Text Available This paper presents experimental results on an innovative electric driveline employing a kinetic energy storage device as energy buffer. A conceptual division of losses in the system was created, separating the complete system into three parts according to their function. This conceptualization of the system yielded a meaningful definition of the concept of efficiency. Additionally, a thorough theoretical framework for the prediction of losses associated with energy storage and transfer in the system was developed. A large number of spin-down tests at varying pressure levels were performed. A separation of the measured data into the different physical processes responsible for power loss was achieved from the corresponding dependence on rotational velocity. This comparison yielded an estimate of the perpendicular resistivity of the stranded copper conductor of 2.5 × 10−8 ± 3.5 × 10−9. Further, power and energy were measured system-wide during operation, and an analysis of the losses was performed. The analytical solution was able to reproduce the measured distribution of losses in the system to an accuracy of 4.7% (95% CI. It was found that the losses attributed to the function of kinetic energy storage in the system amounted to between 45% and 65%, depending on usage.

  13. Low Power Analysis of Network-Level On-chip communication using Asynchronous AMBA protocol

    Directory of Open Access Journals (Sweden)

    E. Sakthivel

    2012-07-01

    Full Text Available Network on-chip (NoC is a novel structuraldesign template, which can be defied for complicatedsystem level on-chip design. NoC has a potential tolimit and present the bus-based communication. In thispaper, the crisis to discuss is Low power consumptionin an Asynchronous Network on-chip (NoC levelcommunication. NoC is implemented using FPGAwhich has less fabrication cost and reduces thecomplexity. An Asynchronous NoC has beenimplemented in Spartan kit using Xilinx FPGA ISEtools and its network interface is AdvancedMicrocontroller Bus Architecture (AMBA whichfeatures numerous bus masters and a sole clock edgeevolution and so on. Here the AMBA highperformance 32-bit AHB bus is employed in which ithas a high clock frequency system and it is the heart ofour bus system. To accomplish low power consumptionby interfacing SoC with AMBA- AHB protocol. TheAHB model and an Asynchronous NoC are employedand executed using VHDL programming module

  14. Exergetic optimization of single level combined gas-steam power plants considering different objective functions

    Energy Technology Data Exchange (ETDEWEB)

    Bracco, Stefano [Department of Turbomachinery, Energy Systems and Transportation, University of Genova, Via Montallegro 1, 16145 Genova (Italy); Siri, Silvia [Department of Communications, Computer and Systems Science, University of Genova, Via Opera Pia 13, 16145 Genova (Italy)

    2010-12-15

    Combined cycle power plants have been studied in this paper with the aim of optimizing the heat recovery steam generator using a first and second law approach. To this end, a mathematical model has been developed for determining the optimal steam pressure in a one pressure level heat recovery steam generator, considering that the gas turbine is known. Different objective functions have been analysed in this study, some of which refer only to the exergy balance of the heat recovery steam generator while others involve the whole bottoming cycle. Some constraints for the operating parameters of the power plant have also been taken into account, regarding for instance the steam quality at the turbine outlet and the steam turbine blade height. Some numerical results have been reported in the paper, comparing the different objective functions for heat recovery steam generators coupled with several gas turbines; the developed parametric analysis has been performed in order to evaluate the influence of some parameters on both the heat recovery steam generator and the whole bottoming cycle. (author)

  15. Determination of 93Zr in medium and low level radioactive wastes from Brazilian nuclear power plants

    International Nuclear Information System (INIS)

    The majority of long-lived radionuclides produced in the nuclear power plants can be regarded as difficult-to-measure radionuclides (RDM), hence chemical separation is necessary before the nuclear measurement of them. The zirconium isotope 93Zr is a long-lived pure β-particle-emitting radionuclide produced from 235U fission and from neutron activation of the stable isotope 92Zr and thus occurring as one of the radionuclides found in nuclear reactors. Due to its long half-life, 93Zr is one of the radionuclides of interest for the performance of assessment studies of waste storage or disposal. Two different methodologies based on extractive resins and LSC and ICP-MS techniques that enables the 93Zr determination in medium (ILW) and low level (LLW) radioactive wastes samples from Brazilian nuclear power plants has been developed in our laboratory. Analyzing real samples 65% and 75% chemical yields for 93Zr recovery were achieved for ICP-MS and LSC techniques, respectively. The detection limits were 0.045 μg.L-1 for ICP-MS and 0.05 Bq.L-1 for LSC techniques. (author)

  16. A Demonstration of Spectral Level Reconstruction of Intrinsic $B$-mode Power

    CERN Document Server

    Pal, Barun

    2016-01-01

    We investigate the prospects and consequences of the spectral level reconstruction of primordial $B$-mode power by solving the systems of linear equations assuming that the lensing potential together with the lensed polarization spectra are already in hand. We find that this reconstruction technique may be very useful to have an estimate of the amplitude of primordial gravity waves or more specifically the value of tensor to scalar ratio. We also see that one can have cosmic variance limited reconstruction of the intrinsic $B$-mode power up to few hundred multipoles ($\\ell\\sim500$) which is more than sufficient to have an estimate of the tensor to scalar ratio. Since the small scale cosmic microwave background (CMB henceforth) anisotropies are not sourced by the primordial gravity waves generated during inflation. We also find that the impact of instrumental noise may be bypassed within this reconstruction algorithm. A simple demonstration for the nullification of the instrumental noise anticipating COrE like...

  17. INFLUENCES OF THE PURCHASING POWER CHANGE ON THE EVOLUTION OF THE AGROALIMETARY MARKETS ON EUROPEAN UNION LEVEL

    OpenAIRE

    Laura Catalina Timiras

    2014-01-01

    This paper aims to identify the manifested connection between the dynamics of the population purchasing power and the dynamic of agroalimentary markets in general as well as by product types on European Union level. Based on the last data supplied by Eurostat 2013, using the specific methods for studying the correlations, we have detected that increases and decreases of the purchasing power generated similar changes on agroalimentary markets level from the point of view of achieved sales in m...

  18. Determination of the Level of Influence of Various Factors on the Reliability of Power System

    Directory of Open Access Journals (Sweden)

    Victor Popescu

    2014-09-01

    Full Text Available Consumers supply with qualitative electric power is one of the priority requirements imposed to power systems. Currently, in electricity networks take place a number of planned and unplanned disconnections, which interrupt the power and affect consumers, causing economic damage. To ensure the quality of power supply it is essential to know the factors that influence the reliability of power systems, which have a visible impact on the variation of reliability of equipment installed in power systems. This paper is devoted to problems of calculation and analysis of power systems reliability and estimation of the impact of various factors that influence the supply of consumers.

  19. Analysis of SG level control system stability after power uprating at Kori 3 and 4 and Ygn 1 and 2

    International Nuclear Information System (INIS)

    Poor control of the steam generator water level in the secondary system of a nuclear power plant after power uprating at Kori Unit 3 and 4 and Younggwang Unit 1 and 2 can lead to frequent reactor shutdowns. Such shutdowns are caused by violation of safety limits on the water level. The performance of steam generator level control system has been evaluated. The purposes of simulation analysis are to provide the expected plant responses as follows; 1) To support training plant operators and engineering personnel in preparation for performing the actual site test. 2) For evaluation to determine appropriate SG level control system setpoints in advance of performing the site startup test

  20. Power posing: brief nonverbal displays affect neuroendocrine levels and risk tolerance.

    Science.gov (United States)

    Carney, Dana R; Cuddy, Amy J C; Yap, Andy J

    2010-10-01

    Humans and other animals express power through open, expansive postures, and they express powerlessness through closed, contractive postures. But can these postures actually cause power? The results of this study confirmed our prediction that posing in high-power nonverbal displays (as opposed to low-power nonverbal displays) would cause neuroendocrine and behavioral changes for both male and female participants: High-power posers experienced elevations in testosterone, decreases in cortisol, and increased feelings of power and tolerance for risk; low-power posers exhibited the opposite pattern. In short, posing in displays of power caused advantaged and adaptive psychological, physiological, and behavioral changes, and these findings suggest that embodiment extends beyond mere thinking and feeling, to physiology and subsequent behavioral choices. That a person can, by assuming two simple 1-min poses, embody power and instantly become more powerful has real-world, actionable implications. PMID:20855902

  1. Impacts from a fossil fuel power plant on ozone levels in Memphis, Tennessee

    International Nuclear Information System (INIS)

    The Tennessee Valley Authority (TVA) Allen power plant is located on the Mississippi River in the southwest corner of Memphis, Tennessee. Allen has three coal-fired cyclone boilers with a rated capacity of 272 MW each. It is a Phase 2 plant under Title IV of the Clean Air Act and is the largest single source of NOx in the Memphis area. TVA plans to reduce Allen NOx emissions through a combination of burning low-sulfur coal (which has the benefit of reducing NOx emissions while also reducing SO2 emissions) and installing gas re-burn technology. A modeling study using the SAI, Inc., UAM-V photochemical model was conducted to examine the potential impacts of NOx reductions on ozone levels in the Memphis area. A series of four model simulations were made in which different Allen emissions scenarios were examined. The focus period of the photochemical modeling was 11--14 July 1995 when measurements in and near Memphis indicated peak hourly ozone levels of 135--140 ppb. This analysis primarily examined computed impacts within 50 km of Memphis. Allen was computed to contribute as much as 20--30 ppb to ground ozone levels 20-50 km downwind using its NOx emission rate before Title IV compliance. After compliance it was computed to contribute only about 10--20 ppb. At the same time, maximum daily ozone reductions due to Allen NOx titration of ozone were between 30 and 60 ppb. These benefits will be reduced by 30--50% after Title IV compliance, and are expected to occur within 30 km of the plant. More model grid cells indicated dis-benefits (net ground-level ozone increases) than benefits on three of the four episode days using the Title IV compliance emission rate. Significant ozone dis-benefits were expected because of the well-documented NO titration of ozone within plumes having a high ratio of NO to volatile organic compounds

  2. Efficiency improvement of transport service by trolley buses based on the levels of their power demand

    Directory of Open Access Journals (Sweden)

    V. V. Aulin

    2014-12-01

    Full Text Available Purpose. Use efficiency improvement of trolley buses in passenger traffic based on power levels of electric energy input and terms adjustment of their maintenance. Methodology. In order to achieve this goal conformance of electric energy input by trolleybus to the transported amount of passengers taking into account characteristics of the route is offered to establish. The major indicators of the trolleybus operation are: speed of a race on lines, number of tractive motor firing, voltage and amperage in the network that were taken with accountants from a dashboard. Research results were tabulated and recorded with DVR. Along with the study of power consumption of electric energy input by a trolleybus passenger count was carried out too. Findings. The directly proportional dependence between the level of energy consumption by a trolleybus and the number of passengers for constant performance route was determined. Originality. As the criteria for evaluating the effectiveness of the trolleybus operation on the route is proposed to use the ratio between electricity consumption and number of passengers for these characteristics of the route. This is confirmed experimentally. The obtained formulas give the possibility to balance the force work and consequently the volume of energy consumption during the trolleybus movement on the rise and the descent. Practical value. The proposed criterion can be used to adjust the terms of maintenance on the individual program, that means individual maintenance (IM. Type of work performed at the IM should be determined on the basis of diagnostic data of the vehicle (V. The principles of IM were formulated: 1 the primary task is planned and preventative strategy to identify and eliminate troubleshooting and technical actions; 2 operational control of the vehicle (V technical condition on the basis of prediction of its state using the proposed criteria, that takes into account the dependence of power consumption to

  3. Dependence of form factors for power and temperature on time and power level at FDR-type reactors

    International Nuclear Information System (INIS)

    In order to test neutron power and fuel temperature form factor variations in a reactor core during operational transients several calculations were performed by means of the dynamics program KINE. This code includes one-dimensional time-dependent feedbacks in order to check-point reactor model calculations. It could be shown that the variation of the form factor was positive or negative dependent on the transient, but not more than 3%. At a hypothetical accident with an unrealistic increase of power by 70% an increase of the form factors by about 10% resulted, which is small compared to the safety margins in quasistationary accident analyses with a point model. (orig.)

  4. A RESEARCH TO HIGH-PERFORMANCE MULTI-LEVEL SINGLEPHASE AC/DC POWER FACTOR CORRECT SWITCHING CONVERTER

    Institute of Scientific and Technical Information of China (English)

    Gao Chao

    2008-01-01

    This letter studies and analyzes the working features of main circuit of tri-level boost Power Factor Correct (PFC) converter and the advantages of tri-level switch converter in aspects of bearing high-voltage of power components,overall system loss and magnetic component selection based upon the single-level boost PFC switch converter. Besides,relying on the application of mi-croprocessor in power converter technology and DSP (Digital Signal Processing) chip's strong cal-culating capacity,the letter presents the adoption of modified scheme of tri-level boost PFC converter under the control of predictive control algorithm. Moreover,the operating principle and control method are specified,the results of circuit test and analysis are provided and the advantages of pre-dictive control technology-based multi-level boost PFC converter is verified.

  5. Output Feedback Dissipation Control for the Power-Level of Modular High-Temperature Gas-Cooled Reactors

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2011-11-01

    Full Text Available Because of its strong inherent safety features and the high outlet temperature, the modular high temperature gas-cooled nuclear reactor (MHTGR is the chosen technology for a new generation of nuclear power plants. Such power plants are being considered for industrial applications with a wide range of power levels, thus power-level regulation is very important for their efficient and stable operation. Exploiting the large scale asymptotic closed-loop stability provided by nonlinear controllers, a nonlinear power-level regulator is presented in this paper that is based upon both the techniques of feedback dissipation and well-established backstepping. The virtue of this control strategy, i.e., the ability of globally asymptotic stabilization, is that it takes advantage of the inherent zero-state detectability property of the MHTGR dynamics. Moreover, this newly built power-level regulator is also robust towards modeling uncertainty in the control rod dynamics. If modeling uncertainty of the control rod dynamics is small enough to be omitted, then this control law can be simplified to a classical proportional feedback controller. The comparison of the control performance between the newly-built power controller and the simplified controller is also given through numerical study and theoretical analysis.

  6. Dose estimation for nuclear power plant 4 accident in Taiwan at Fukushima nuclear meltdown emission level.

    Science.gov (United States)

    Tang, Mei-Ling; Tsuang, Ben-Jei; Kuo, Pei-Hsuan

    2016-05-01

    An advanced Gaussian trajectory dispersion model is used to evaluate the evacuation zone due to a nuclear meltdown at the Nuclear Power Plant 4 (NPP4) in Taiwan, with the same emission level as that occurred at Fukushima nuclear meltdown (FNM) in 2011. Our study demonstrates that a FNM emission level would pollute 9% of the island's land area with annual effective dose ≥50 mSv using the meteorological data on 11 March 2011 in Taiwan. This high dose area is also called permanent evacuation zone (denoted as PEZ). The PEZ as well as the emergency-planning zone (EPZ) are found to be sensitive to meteorological conditions on the event. In a sunny day under the dominated NE wind conditions, the EPZ can be as far as 100 km with the first 7-day dose ≥20 mSv. Three hundred sixty-five daily events using the meteorological data from 11 March 2011 to 9 March 2012 are evaluated. It is found that the mean land area of Taiwan in becoming the PEZ is 11%. Especially, the probabilities of the northern counties/cities (Keelung, New Taipei, Taipei, Taoyuan, Hsinchu City, Hsinchu County and Ilan County) to be PEZs are high, ranging from 15% in Ilan County to 51% in Keelung City. Note that the total population of the above cities/counties is as high as 10 million people. Moreover, the western valleys of the Central Mountain Range are also found to be probable being PEZs, where all of the reservoirs in western Taiwan are located. For example, the probability can be as high as 3% in the far southern-most tip of Taiwan Island in Pingtung County. This shows that the entire populations in western Taiwan can be at risk due to the shortage of clean water sources under an event at FNM emission level, especially during the NE monsoon period.

  7. Minimizing the Levelized Cost of Energy in Single-Phase Photovoltaic Systems with an Absolute Active Power Control

    DEFF Research Database (Denmark)

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya;

    2015-01-01

    Several countries with considerable PhotoVoltaic (PV) installations are facing a challenge of overloading the power infrastructure during peak-power production hours. Regulations have been imposed on the PV systems, where more active power control should be flexibly performed. As an advanced...... method is demonstrated on a 3-kW single-phase PV system considering a real-field mission profile (i.e., solar irradiance and ambient temperature). The optimization results have revealed that superior performance in terms of LCOE and energy production can be obtained by enabling the AAPC strategy......, compared to the conventional PV inverter operating only in the maximum power point tracking mode. In the presented case study, the minimum of LCOE is achieved for the system when the power limit is optimized to a certain level of the designed maximum feed-in power (i.e., 3 kW). In addition, the proposed...

  8. The effects of a maximal power training cycle on the strength, maximum power, vertical jump height and acceleration of high-level 400-meter hurdlers.

    Science.gov (United States)

    Balsalobre-Fernández, Carlos; Tejero-González, Carlos M; Del Campo-Vecino, Juan; Alonso-Curiel, Dionisio

    2013-03-01

    The aim of this study was to determine the effects of a power training cycle on maximum strength, maximum power, vertical jump height and acceleration in seven high-level 400-meter hurdlers subjected to a specific training program twice a week for 10 weeks. Each training session consisted of five sets of eight jump-squats with the load at which each athlete produced his maximum power. The repetition maximum in the half squat position (RM), maximum power in the jump-squat (W), a squat jump (SJ), countermovement jump (CSJ), and a 30-meter sprint from a standing position were measured before and after the training program using an accelerometer, an infra-red platform and photo-cells. The results indicated the following statistically significant improvements: a 7.9% increase in RM (Z=-2.03, p=0.021, δc=0.39), a 2.3% improvement in SJ (Z=-1.69, p=0.045, δc=0.29), a 1.43% decrease in the 30-meter sprint (Z=-1.70, p=0.044, δc=0.12), and, where maximum power was produced, a change in the RM percentage from 56 to 62% (Z=-1.75, p=0.039, δc=0.54). As such, it can be concluded that strength training with a maximum power load is an effective means of increasing strength and acceleration in high-level hurdlers.

  9. The Level of Power Quality Measurement and Evaluation in A Stone Crusher Plant

    OpenAIRE

    ŞEKKELİ, Mustafa; A.Serdar YILMAZ

    2009-01-01

    Both electric utilities and end users of electric power are becoming increasingly concerned about the quality of electric power. Quality of electrical energy in the electrical system that is requested continuous power (uninterrupted power), constant frequency and with constant amplitude can be explained by sinusoidal voltage. Deformation of voltage in the form of sinusoidal waveform is explained as a harmonic. Harmonics are most important factors in decreasing quality of energy in the electri...

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

    NARCIS (Netherlands)

    Popovic, J.

    2005-01-01

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

  11. Deconstructing the power resistance relationship for squats: A joint-level analysis.

    Science.gov (United States)

    Farris, D J; Lichtwark, G A; Brown, N A T; Cresswell, A G

    2016-07-01

    Generating high leg power outputs is important for executing rapid movements. Squats are commonly used to increase leg strength and power. Therefore, it is useful to understand factors affecting power output in squatting. We aimed to deconstruct the mechanisms behind why power is maximized at certain resistances in squatting. Ten male rowers (age = 20 ± 2.2 years; height = 1.82 ± 0.03 m; mass = 86 ± 11 kg) performed maximal power squats with resistances ranging from body weight to 80% of their one repetition maximum (1RM). Three-dimensional kinematics was combined with ground reaction force (GRF) data in an inverse dynamics analysis to calculate leg joint moments and powers. System center of mass (COM) velocity and power were computed from GRF data. COM power was maximized across a range of resistances from 40% to 60% 1RM. This range was identified because a trade-off in hip and knee joint powers existed across this range, with maximal knee joint power occurring at 40% 1RM and maximal hip joint power at 60% 1RM. A non-linear system force-velocity relationship was observed that dictated large reductions in COM power below 20% 1RM and above 60% 1RM. These reductions were due to constraints on the control of the movement.

  12. An Artificial Neural Network Compensated Output Feedback Power-Level Control for Modular High Temperature Gas-Cooled Reactors

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2014-02-01

    Full Text Available Small modular reactors (SMRs could be beneficial in providing electricity power safely and also be viable for applications such as seawater desalination and heat production. Due to its inherent safety features, the modular high temperature gas-cooled reactor (MHTGR has been seen as one of the best candidates for building SMR-based nuclear power plants. Since the MHTGR dynamics display high nonlinearity and parameter uncertainty, it is necessary to develop a nonlinear adaptive power-level control law which is not only beneficial to the safe, stable, efficient and autonomous operation of the MHTGR, but also easy to implement practically. In this paper, based on the concept of shifted-ectropy and the physically-based control design approach, it is proved theoretically that the simple proportional-differential (PD output-feedback power-level control can provide asymptotic closed-loop stability. Then, based on the strong approximation capability of the multi-layer perceptron (MLP artificial neural network (ANN, a compensator is established to suppress the negative influence caused by system parameter uncertainty. It is also proved that the MLP-compensated PD power-level control law constituted by an experientially-tuned PD regulator and this MLP-based compensator can guarantee bounded closed-loop stability. Numerical simulation results not only verify the theoretical results, but also illustrate the high performance of this MLP-compensated PD power-level controller in suppressing the oscillation of process variables caused by system parameter uncertainty.

  13. Chamber wall materials response to pulsed ions at power-plant level fluences

    Science.gov (United States)

    Renk, T. J.; Provencio, P. P.; Tanaka, T. J.; Olson, C. L.; Peterson, R. R.; Stolp, J. E.; Schroen, D. G.; Knowles, T. R.

    2005-12-01

    Candidate dry-wall materials for the reactor chambers of future laser-driven Inertial Fusion Energy (IFE) power plants have been exposed to ion pulses from RHEPP-1, located at Sandia National Laboratories. These pulses simulate the MeV-level ion pulses with fluences of up to 20 J/cm 2 that can be expected to impinge on the first wall of such future plants. Various forms of tungsten and tungsten alloy were subjected to up to 1600 pulses, usually while being heated to 600 °C. Other metals were exposed as well. Thresholds for roughening and material removal, and evolution of surface morphology were measured and compared with code predictions for materials response. Powder-metallurgy (PM) tungsten is observed to undergo surface roughening and subsurface crack formation that evolves over hundreds of pulses, and which can occur both below and above the melt threshold. This roughening is worse than for other metals, and worse than for either tungsten alloyed with rhenium (W25Re), or for CVD and single-crystal forms of tungsten. Carbon, particularly the form used in composite material, appears to suffer material loss well below its sublimation point. Some engineered materials were also investigated. It appears that some modification to PM tungsten is required for its successful use in a reactor environment.

  14. MONSTROUS HAZARDS PRODUCED BY HIGH RADIOACTIVITY LEVELS AROUND ASSIUT THERMAL POWER PLANT

    Directory of Open Access Journals (Sweden)

    Hany El-Gamal

    2013-01-01

    Full Text Available The natural radioactivity level of heavy oil, ash and soil samples around Assiut Thermal Power Plant (ATPP in Egypt was determined using gamma ray spectrometry. The average concentrations of 226Ra, 232Th and 40K in fly ash were found to be 2307±143, 1281±80 and 1218±129 Bq kg-1, respectively, while the corresponding values in soil samples were 2670±107, 1401±78 and 1495±100 Bq kg-1, respectively. These are extremely high and higher by several orders of magnitude than the worldwide population-weighted average values in soil. The radium equivalent activity, the air absorbed dose rate, external hazard index and the annual effective dose rate were calculated and compared with the international recommended values. All averages of these parameters are much higher by several orders of magnitude than the international recommended values, indicating significant radiological health hazards around ATPP due to the radionuclides in the soil. Moreover, the water samples investigated have high activity concentrations indicating that the water is highly contaminated with radioactive materials. The results of the current study highlight the severity of this radioactive pollution on the population in the vicinity of ATPP.

  15. Costs of reducing water use of concentrating solar power to sustainable levels: Scenarios for North Africa

    International Nuclear Information System (INIS)

    Concentrating solar power (CSP) has the potential to become a leading sustainable energy technology for the European electricity system. In order to reach a substantial share in the energy mix, European investment in CSP appears most profitable in North Africa, where solar potential is significantly higher than in southern Europe. As well as sufficient solar irradiance, however, the majority of today's CSP plants also require a considerable amount of water, primarily for cooling purposes. In this paper we examine water usage associated with CSP in North Africa, and the cost penalties associated with technologies that could reduce those needs. We inspect four representative sites to compare the ecological and economical drawbacks from conventional and alternative cooling systems, depending on the local environment, and including an outlook with climate change to the mid-century. Scaling our results up to a regional level indicates that the use of wet cooling technologies would likely be unsustainable. Dry cooling systems, as well as sourcing of alternative water supplies, would allow for sustainable operation. Their cost penalty would be minor compared to the variance in CSP costs due to different average solar irradiance values. - Highlights: → Scaling up CSP with wet cooling from ground water will be unsustainable in North Africa. → Desalination and alternative cooling systems can assure a sustainable water supply. → On large-scale, the cost penalties of alternative cooling technologies appear minor.

  16. Regime resistance against low-carbon energy transitions: Introducing politics and power in the multi-level perspective

    OpenAIRE

    Frank Geels

    2014-01-01

    While most studies of low-carbon transitions focus on green niche-innovations, this paper shifts attention to the resistance by incumbent regime actors to fundamental change. Drawing on insights from political economy, the paper introduces politics and power into the multi-level perspective. Instrumental, discursive, material and institutional forms of power and resistance are distinguished and illustrated with examples from the UK electricity system. The paper concludes that the resistance a...

  17. Development of a Tool for Windfarm Site Analysis in Electrical Networks with High Levels of Wind Power Generation

    OpenAIRE

    Carroll, Edward; McGrory, John

    2010-01-01

    Controlling electrical networks that contain high levels of wind power will be a challenge facing many System Operators in the coming years. The intermittency and uncertainty of the power supplied by wind turbines create difficulties surrounding scheduling of plant, operating reserve and grid integration. The current process for windfarm selection is carried out by an individual stakeholder and lacks the consideration for all other stakeholders involved, which can create problems in the long ...

  18. Compact high-power tunable three-level operation of double cladding Nd-doped fiber laser

    OpenAIRE

    Fu, L. B.; Ibsen, M; Richardson, D J; Nilsson, J.; Payne, D. N.; Grudinin, A. B.

    2005-01-01

    We present a compact high-power continuous-wave tunable neodymium-doped double cladding fiber laser operating on three-level 4F3/2 - 4I9/2 transition with a maximum output power up to 810 mW. At 926.7 nm, it has a maximum slope efficiency of 49.3% against absorbed 808-nm pump. By compressing the fiber Bragg grating, 15-nm tuning range is achieved.

  19. Power

    DEFF Research Database (Denmark)

    Elmholdt, Claus Westergård; Fogsgaard, Morten

    2016-01-01

    In this chapter, we will explore the dynamics of power in processes of creativity, and show its paradoxical nature as both a bridge and a barrier to creativity in organisations. Recent social psychological experimental research (Slighte, de Dreu & Nijstad, 2011) on the relation between power...... and creativity suggests that when managers give people the opportunity to gain power and explicate that there is reason to be more creative, people will show a boost in creative behaviour. Moreover, this process works best in unstable power hierarchies, which implies that power is treated as a negotiable...... and floating source for empowering people in the organisation. We will explore and discuss here the potentials, challenges and pitfalls of power in relation to creativity in the life of organisations today. The aim is to demonstrate that power struggles may be utilised as constructive sources of creativity...

  20. Statistical properties of radiation power levels from a high-gain free-electron laser at and beyond saturation

    International Nuclear Information System (INIS)

    We investigate the statistical properties (e.g., shot-to-shot power fluctuations) of the radiation from a high-gain free-electron laser (FEL) operating in the nonlinear regime. We consider the case of an FEL amplifier reaching saturation whose shot-to-shot fluctuations in input radiation power follow a gamma distribution. We analyze the corresponding output power fluctuations at and beyond first saturation, including beam energy spread effects, and find that there are well-characterized values of undulator length for which the fluctuation level reaches a minimum

  1. An advanced static var compensator based on a three level IGBT inverter modelling analysis and active power filtering

    Science.gov (United States)

    Draou, Azeddine

    2012-12-01

    This paper presents the dynamic performance analysis of an Advanced Static Var Compensator (ASVC) using three-level neutral point-clamped voltage source inverter. The paper presents the principles of operating and the method of reference currents generation. The dynamic behaviour of the system is further analysed using Matlab/Simulink with SimPower Systems toolbox through a set of simulation tests. The results obtained have been applied to an active power filter which might lead to the design of a robust controller for current harmonics and reactive power applications

  2. Coherent Power Analysis in Multi-Level Studies Using Design Parameters from Surveys

    Science.gov (United States)

    Rhoads, Christopher

    2016-01-01

    Current practice for conducting power analyses in hierarchical trials using survey based ICC and effect size estimates may be misestimating power because ICCs are not being adjusted to account for treatment effect heterogeneity. Results presented in Table 1 show that the necessary adjustments can be quite large or quite small. Furthermore, power…

  3. Thermal analysis of two-level wind power converter under symmetrical grid fault

    DEFF Research Database (Denmark)

    Zhou, Dao; Blaabjerg, Frede

    2013-01-01

    ) condition as well as the junction temperature. For the full-scale wind turbine system, the most thermal stressed power device in the grid-side converter will appear at the grid voltage below 0.5 pu, and for the partial-scale wind turbine system, the most thermal stressed power device in the rotor...

  4. Power

    OpenAIRE

    Hafford-Letchfield, Trish

    2015-01-01

    This chapter looks at the concept of power in social work by focusing on what this means as a ‘professional’ and theorizes competing discourses of empowerment in social work and its key concepts, drawing in particular on the explanatory powers of critical theorist Michel Foucault (1991). The chapter problematizes the concept of power by explicitly drawing on both users’ and carers’ accounts from the literature to demonstrate different external and internal influences on the root causes of dis...

  5. Influence of power level and fuel type on safety and economy of the simplified pebble bed HTR concept

    International Nuclear Information System (INIS)

    For three different power levels, 20, 40 and 150 MWth, the PAP-HTR has been studied. This is an HTR Module concept that has been simplified in such a way that the continuously defuelling system has been eliminated and no defuelling takes place during a period of several years. Two core heatup scenarios have been simulated. It has been shown that in all cases the maximum fuel pebble temperature remains below 1600C, the temperature above which fuel degradation would start to occur, also after the reactor has gone critical again and the power level has been stabilized by itself. Fuel and gas temperature distributions are compared as well. The maximum pebble temperature before recriticality is higher for the loss of coolant (LOCA) scenario than for the loss of flow (LOFA) case, but the equilibrium maximum temperature after recriticality turns out to be higher for the pressurized case, because of the higher equilibrium power level. The equilibrium power level is a much smaller fraction of the nominal power level for the large 150 MWth system than for the smaller systems, due to the lower rate of cooling down of the large system after initiation of the accident. Therefore the equilibrium maximum temperature stays within acceptable limits for the large system too. The effects of the use of thorium fuel on the core height and waste radiotoxicity have been compared with the case of uranium fuel. Although it is widely believed that burnt thorium fuel would be cleaner than spent uranium fuel in terms of radiotoxicity, this did not appear to be more pronounced for this reactor concept than for e.g. PWRs. The relationship of power level and energy price is obvious for this power range. The use of thorium with highly enriched uranium could bring an additional economical advantage because of the lower core height needed for the same power level as the uranium case. With thorium a higher burnup can be attained, through which fuel pebbles can be added at a slower rate. The size of

  6. 3MW双馈风力发电机传热特性数值研究%Numerical Investigation of Heat Transfer for 3 MW Doubly-fed Wind Generators

    Institute of Scientific and Technical Information of China (English)

    丁树业; 孙兆琼; 徐殿国; 苗立杰

    2012-01-01

    随着风力发电机容量的增加,电磁负荷不断提高,电机的发热问题成为影响机组性能和经济指标的主要因素之一。为了解决该难题,以一台3MW双馈风力发电机为例,根据流体力学以及传热学理论,结合发电机通风性能以及结构特点,建立了发电机三维流动与传热耦合求解的数学模型与物理模型;并给出基本假设与相应的边界条件,采用有限体积法对三维流体场和温度场控制方程进行耦合计算。最后,对发电机内部的流体流动性能、传热特性以及发电机定转子铁心、定转子绕组以及绝缘的温升分布进行了分析,得到端部气体流动不规律以及二次冷却热能力较强等,为更大容量风力发电机综合物理场的准确计算提供了理论依据。%With the increase of wind generator capacity and electromagnetic load,heating problem becomes one of the major factors that would affect the performance and economic benefit of generating set.To solve the problem,a 3 MW double-fed wind generator was taken as an example.On the basis of hydromechanics and heat transfer theory,the mathematical and physical model of 3D fluid flow and heat transfer coupled was established according to structure characteristic of generator.The governing equation of fluid-flow and thermal field was calculated coupled using finite volume method by giving fundamental assumptions and corresponding boundary conditions.Finally,the performance of fluid flow,characteristic of heat transfer,and temperature rise distribution of stator and rotor were analyzed in detail.Some useful conclusions were achieved,by which a theory gist for accurate calculation of synthetic physical fields for the larger capacity wind generator is provided.

  7. 3MW永磁风力发电机内部传热特性研究%Investigation of Heat Transfer Characteristic inside 3MW Permanent Magnet Wind Generator

    Institute of Scientific and Technical Information of China (English)

    丁树业; 苗立杰; 徐殿国; 陈卫杰

    2012-01-01

    由于风力发电机的容量增加,发电机的通风结构和损耗分布也变得越来越复杂,电机的温升设计成为关键问题之一.为了解决这一难题,本文根据流体力学以及传热学理论,阐明了流体与固体耦合直接求解温度场的数学关系.并且以一台3MW大型永磁风力发电机为例,结合发电机通风性能以及结构特点,在基本假设的基础上,建立了发电机三维定转子温度场物理模型.通过给出相应的边界条件,采用有限体积元法对发电机内部的温度场进行了数值计算.最后对发电机内部的传热特性以及温升分布进行了详细地分析,为发电机结构优化以及更大容量风力发电机的温升设计提供了理论依据.%Ventilation structure and loss distribution of wind generator become more complex due to increase of its capacity, and design of temperature rise becomes one of the pivotal problems. The numerical relationship of fluid and solid coupled, by which thermal filed is computed directly, is clarified in this paper in order to solve the matter according to hydromechanics and heat transfer theory. A 3MW large permanent magnet wind generator was taken as an example, physical model of three dimensional stator and rotor temperature field was established on the basis of basic assumptions considering ventilation characteristic and structure feature of generator. The thermal field inside generator was calculated numerically using finite volume method by giving corresponding boundary conditions. Finally, heat transfer characteristic and temperature rise distribution of generator were analyzed in detail, by which a theory gist for structure optimization of the generator and thermal rise design of the larger capacity wind generator is provided.

  8. Use of Three-Level Power Converters in Wind-Driven Permanent-Magnet Synchronous Generators with Unbalanced Loads

    Directory of Open Access Journals (Sweden)

    Ming-Hung Chen

    2015-06-01

    Full Text Available This paper describes the design and implementation of three-level power converters for wind-driven permanent-magnet synchronous generators with unbalanced loads. To increase voltage stress and reduce current harmonics in the electrical power generated by a wind generator, a three-phase, three-level rectifier is used. Because a synchronous rotating frame is used on the AC-input side, the use of a neutral-point-clamped controller is proposed to increase the power factor to unity and reduce current harmonics. Furthermore, a novel six-leg inverter is proposed for transferring energy from the DC voltage to a three-phase, four-wire AC source with a constant voltage and a constant frequency. The power converters also contain output transformers and filters for power buffering and filtering, respectively. All three output phase voltages are fed back to control the inverter output during load variations. A digital signal processor is used as the core control device for implementing a 1.5 kV, 75 kW drive system. Experimental data show that the power factor is successfully increased to unity and the total current harmonic distortion is 3.2% on the AC-input side. The entire system can attain an efficiency of 91%, and the voltage error between the upper and lower capacitors is approximately zero. Experimental results that confirm the high performance of the proposed system are presented.

  9. Long pulse H- beam extraction with a rf driven ion source on a high power level

    International Nuclear Information System (INIS)

    IPP Garching is investigating the applicability of rf driven negative ion sources for the neutral beam injection of International Thermonuclear Experimental Reactor. The setup of the tested source was improved to enable long pulses up to 100 kW rf power. The efficiency of negative ion production decreases at high power. The extracted H- currents as well as the symmetry of the plasma density close to the plasma grid and of the beam divergence depend on the magnetic filter field. The pulse duration is limited by the increase in coextracted electrons, which depends on the rf power and the caesium conditions on the plasma grid.

  10. Manpower development for each level of nuclear power plant personnel, experience and problems

    International Nuclear Information System (INIS)

    The following topics to be covered in this report are: Power plant organization and staff categories; basic education and training; practical experience requirements; effects of promotion and fluctuation; social problems associated with training abroad; technical problems and solutions. (orig.)

  11. Real-Time Estimation of Power System Frequency Using a Three-Level Discrete Fourier Transform Method

    Directory of Open Access Journals (Sweden)

    Soon-Ryul Nam

    2014-12-01

    Full Text Available This paper proposes a three-level discrete Fourier transform (DFT method to provide an accurate estimate of power system frequency in real time. The first level decomposes a power system signal into two orthogonal cosine- and sine-filtered signals. The second and third levels are used to determine the amplitude ratio of the cosine- and sine-filtered signals without encountering the zero-crossing problem and with an increase in ability to suppress harmonics and inter-harmonics. The performance of the three-level DFT method is evaluated using computer-simulated signals with harmonics and inter-harmonics. The three-level DFT method is also implemented on a digital signal processor (DSP-based hardware prototype, and its performance in the hardware implementation is evaluated using a real-time digital simulator (RTDS. The evaluation results show that the three-level DFT method can achieve real-time estimation of power system frequency with satisfactory performance.

  12. A Comprehensive Investigation on the Short Circuit Performance of MW-level IGBT Power Modules

    DEFF Research Database (Denmark)

    Wu, Rui; Reigosa, Paula Diaz; Iannuzzo, Francesco;

    2015-01-01

    This paper investigates the short circuit performance of commercial 1.7 kV / 1 kA IGBT power modules by means of a 6 kA Non-Destructive-Tester. A mismatched current distribution among the parallel chips has been observed, which can reduce the short circuit capability of the IGBT power module unde...... short circuit conditions. Further Spice simulations reveal that the stray parameters inside the module play an important role in contributing to such a phenomenon....

  13. A Comprehensive Investigation on the Short Circuit Performance of MW-level IGBT Power Modules

    OpenAIRE

    Wu, Rui; Reigosa, Paula Diaz; Iannuzzo, Francesco; Wang, Huai; Blaabjerg, Frede

    2015-01-01

    This paper investigates the short circuit performance of commercial 1.7 kV / 1 kA IGBT power modules by means of a 6 kA Non-Destructive-Tester. A mismatched current distribution among the parallel chips has been observed, which can reduce the short circuit capability of the IGBT power module under short circuit conditions. Further Spice simulations reveal that the stray parameters inside the module play an important role in contributing to such a phenomenon.

  14. Development of Ribbon Fiber Type Multi-Channel Power Level Monitor with Low-Insertion/Polarization Loss

    Institute of Scientific and Technical Information of China (English)

    Maki Inai; Akira Haraguchi; Takeo Komiya; Kiyotaka Murashima; Takashi Sasaki; Kazuhito Saitoh

    2003-01-01

    We would like to propose a new in-line multi-channel power level monitor, which is applicable as tap-monitor for multi-channel WDM signals. Its ribbon fiber structure has far exceeded PLC performance and realized compact-size and lower insertion/polarization dependent loss.

  15. Effect of Auricular Acupuncture with Low Power Laser on Four Chronic Allergic Dermatoses and Serum IgE Level

    Institute of Scientific and Technical Information of China (English)

    You-hong Hou; Fang Xu; Shao-xi Wu

    2005-01-01

    @@ The objective of the study was to investigate the effectiveness of low power laser irradiating auricular points on four chronic allergic dermatoses including eczema, urticaria, facial cosmetic dermatitis, and atopic dermatitis, and on the changes of serum IgE level.

  16. Effect of Voltage Level on Power System Design for Solar Electric Propulsion Missions

    Science.gov (United States)

    Kerslake, Thomas W.

    2003-01-01

    This paper presents study results quantifying the benefits of higher voltage, electric power system designs for a typical solar electric propulsion spacecraft Earth orbiting mission. A conceptual power system architecture was defined and design points were generated for system voltages of 28-V, 50-V, 120-V, and 300-V using state-of-the-art or advanced technologies. A 300-V 'direct-drive' architecture was also analyzed to assess the benefits of directly powering the electric thruster from the photovoltaic array without up-conversion. Fortran and spreadsheet computational models were exercised to predict the performance and size power system components to meet spacecraft mission requirements. Pertinent space environments, such as electron and proton radiation, were calculated along the spiral trajectory. In addition, a simplified electron current collection model was developed to estimate photovoltaic array losses for the orbital plasma environment and that created by the thruster plume. The secondary benefits of power system mass savings for spacecraft propulsion and attitude control systems were also quantified. Results indicate that considerable spacecraft wet mass savings were achieved by the 300-V and 300-V direct-drive architectures.

  17. Integrated Solar Power Converters: Wafer-Level Sub-Module Integrated DC/DC Converter

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-02-09

    Solar ADEPT Project: CU-Boulder is developing advanced power conversion components that can be integrated into individual solar panels to improve energy yields. The solar energy that is absorbed and collected by a solar panel is converted into useable energy for the grid through an electronic component called an inverter. Many large, conventional solar energy systems use one, central inverter to convert energy. CU-Boulder is integrating smaller, microinverters into individual solar panels to improve the efficiency of energy collection. The University’s microinverters rely on electrical components that direct energy at high speeds and ensure that minimal energy is lost during the conversion process—improving the overall efficiency of the power conversion process. CU-Boulder is designing its power conversion devices for use on any type of solar panel.

  18. Level of supply security provided by the German power plant fleet

    International Nuclear Information System (INIS)

    The security of Germany's electricity supply is a topic of intense debate. Although it could be discussed in quantitative terms, there has to date been no analytical study of this issue, or at least none reflected in the public debate. One possible measure of the security of supply of the German power plant fleet would be loss-of-load hours. This would have to be calculated by a central authority such as the Federal Network Agency. An estimate has shown that, assuming no other changes to the German power plant fleet, a phase-out of nuclear energy would lead to a substantial increase in annual loss-of-load hours.

  19. Megawatt-level peak-power from a passively Q-switched hybrid fiber-bulk amplifier and its applications

    Science.gov (United States)

    Reiser, Axel; Bdzoch, Juraj; Höfer, Sven; Scholz-Riecke, Sina; Seitz, Daniel; Kugler, Nicolas; Genter, Peter

    2016-03-01

    A novel laser system with optical parameters that fill the gap between Q-switched and modelocked lasers has been developed. It consists of a high gain hybrid fiber-bulk amplifier seeded by a low power SESAM Q-switched oscillator. The mW level output power of the seed oscillator is preamplified by a single mode fiber which is limited by SRS effects. The final amplification stage is realized by a longitudinal pumped Nd:YVO4 crystal in a double pass setup. This MOPA configuration delivers sub-300ps pulses at repetition rates up to 1 MHz with an output power exceeding 60W. Nonlinear frequency conversion to 532nm and 355nm is achieved with efficiencies of >75% and >45%, respectively. Due to the high peak power, high repetition rate and high beam quality of this system, applications formerly only addressable at lower pulse repetition frequencies or with complex modelocked laser systems are now possible with high speed and lower cost of ownership. Application results that take benefit from these new laser parameters will be shown. Furthermore, the reduction of the pulse duration to sub-100ps and power scaling to output powers <100W by the use of the Innoslab concept are being presented.

  20. Drivers for the Value of Demand Response under Increased Levels of Wind and Solar Power; NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    Hale, Elaine

    2015-07-30

    Demand response may be a valuable flexible resource for low-carbon electric power grids. However, there are as many types of possible demand response as there are ways to use electricity, making demand response difficult to study at scale in realistic settings. This talk reviews our state of knowledge regarding the potential value of demand response in several example systems as a function of increasing levels of wind and solar power, sometimes drawing on the analogy between demand response and storage. Overall, we find demand response to be promising, but its potential value is very system dependent. Furthermore, demand response, like storage, can easily saturate ancillary service markets.

  1. Towards a Cellular Automata Based Network Intrusion Detection System with Power Level Metric in Wireless Adhoc Networks (IDFADNWCA)

    OpenAIRE

    Sree, Pokkuluri Kiran; Babu, Inampudi Ramesh

    2014-01-01

    Adhoc wireless network with their changing topology and distributed nature are more prone to intruders. The efficiency of an Intrusion detection system in the case of an adhoc network is not only determined by its dynamicity in monitoring but also in its flexibility in utilizing the available power in each of its nodes. In this paper we propose a hybrid intrusion detection system, based on a power level metric for potential adhoc hosts, which is used to determine the duration for which a part...

  2. An influence of occupational exposure on level of chromosome aberrations in nuclear power plant workers

    International Nuclear Information System (INIS)

    Complete text of publication follows. Objective. The workers of Ignalina Nuclear Power Plant (INPP) receive the highest occupational ionising radiation doses in Lithuania. Their occupational exposure results mainly from external low LET gamma radiation. Some workers receive additional internal and neutron exposure. Though exposure doses are generally low and don't exceed the annual dose limit, the higher doses are obtained during outages. The aim of the present study was to analyse chromosome aberration frequencies in lymphocytes of INPP workers exposed to the different types of ionising radiation. Methods. The blood sampling of 52 INPP male workers was performed in 2004-2006. For 29 workers radiation exposure resulted from the external gamma rays only. Their mean annual dose averaged over the 3-year period prior blood sampling was 11.7±8.7 mSv. The mean cumulative dose - 197.7±174.7 mSv. 15 workers had an intake of gamma radionuclides (60Co, 137Cs), contributing to the doses less than 0.1 mSv. Their mean cumulative dose - 278.2±191.9 mSv. The mean annual dose averaged over the 3-year period prior blood sampling was 11.8±5.3 mSv. For 8 subjects neutron doses below 0.2 mSv were recorded. Their mean annual dose averaged over the 3-year period prior blood sampling was 7.0±2.9 mSv. The mean cumulative dose was 241.8±93.0 mSv. Heparinized venous blood samples were taken and cultures were initiated according to the standard procedures. Phytohaemagglutinin (7.8 μg/ml) stimulated cultures were incubated at 37degC for 72 hours in RPMI 1640 medium supplemented with 12% heat-inactivated newborn calf serum, 40 μg/ml gentamycin. Colchicine was added to the culture during the initiation at a final concentration of 0,25 μg/ml. The harvested lymphocytes were treated with hypotonic KCl (0,075 M) and then fixed in methanol-glacial acetic acid (3:1). Flame-dried slides were stained with Giemsa, coded and scored blind. Generally 500 first-division cells per individual were

  3. Evaluation of SiC Power Diodes against Terrestrial Neutron-Induced Failure at Ground Level

    OpenAIRE

    ASAI, HIROAKI; Sugimoto, Kenji; Nashiyama, Isamu; Shiba, Kensuke; Matsuda, Mieko; Morimura, Tadaaki

    2013-01-01

    Terrestrial neutrons cause single-event effects (SEEs) in semiconductor devices, which crucially affect the reliability of electronic systems used in the terrestrial environment. This paper presents evaluation results of high energy neutron-induced single-event burnout (SEB) in silicon carbide (SiC) power diodes and differences between SiC and silicon (Si) devices from the SEB standpoint.

  4. Teachers, School Boards, and the Power of Money: How the Right Wins at the Local Level

    Science.gov (United States)

    Schirmer, Eleni B.; Apple, Michael W.

    2016-01-01

    This article examines national conservative political advocacy groups' growing interest in local politics, and analyzes how they form alliances and gain political power. Following efforts to restrict collective bargaining for Wisconsin public employees, Kenosha school board members' attempts to legally protect teachers' rights provoked concern…

  5. Low-power chip-level optical interconnects based on bulk-silicon single-chip photonic transceivers

    Science.gov (United States)

    Kim, Gyungock; Park, Hyundai; Joo, Jiho; Jang, Ki-Seok; Kwack, Myung-Joon; Kim, Sanghoon; Kim, In Gyoo; Kim, Sun Ae; Oh, Jin Hyuk; Park, Jaegyu; Kim, Sanggi

    2016-03-01

    We present new scheme for chip-level photonic I/Os, based on monolithically integrated vertical photonic devices on bulk silicon, which increases the integration level of PICs to a complete photonic transceiver (TRx) including chip-level light source. A prototype of the single-chip photonic TRx based on a bulk silicon substrate demonstrated 20 Gb/s low power chip-level optical interconnects between fabricated chips, proving that this scheme can offer compact low-cost chip-level I/O solutions and have a significant impact on practical electronic-photonic integration in high performance computers (HPC), cpu-memory interface, 3D-IC, and LAN/SAN/data-center and network applications.

  6. MS2 virus inactivation by atmospheric-pressure cold plasma using different gas carriers and power levels.

    Science.gov (United States)

    Wu, Yan; Liang, Yongdong; Wei, Kai; Li, Wei; Yao, Maosheng; Zhang, Jue; Grinshpun, Sergey A

    2015-02-01

    In this study, airborne MS2 bacteriophages were exposed for subsecond time intervals to atmospheric-pressure cold plasma (APCP) produced using different power levels (20, 24, and 28 W) and gas carriers (ambient air, Ar-O2 [2%, vol/vol], and He-O2 [2%, vol/vol]). In addition, waterborne MS2 viruses were directly subjected to the APCP treatment for up to 3 min. MS2 viruses with and without the APCP exposure were examined by scanning electron microscopy (SEM), reverse transcription-PCR (RT-PCR), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Viral inactivation was shown to exhibit linear relationships with the APCP generation power and exposure time (R(2) > 0.95 for all energy levels tested) up to 95% inactivation (1.3-log reduction) after a subsecond airborne exposure at 28 W; about the same inactivation level was achieved for waterborne viruses with an exposure time of less than 1 min. A larger amount of reactive oxygen species (ROS), such as atomic oxygen, in APCP was detected for a higher generation power with Ar-O2 and He-O2 gas carriers. SEM images, SDS-PAGE, and agarose gel analysis of exposed waterborne viruses showed various levels of damage to both surface proteins and their related RNA genes after the APCP exposure, thus leading to the loss of their viability and infectivity.

  7. A methodology for Level 2 PSA evaluation with consideration of specific features for Low Power Shutdown Probabilistic Safety Assessment

    International Nuclear Information System (INIS)

    The primary objective of the Level 2 PSA during Lower Power/Shutdown (LPSD) operation is to provide insights into potential plant vulnerabilities with regard to accident progression. The shutdown risk information can be used to provide the information to develop outage risk management guidelines. The LPSD Level 2 analysis utilizes much of the at-power Level 2 analysis for bounding, conservative treatment of severe accident phenomena. But, for some portions of the analysis including Plant Operational States (POSs), LPSD-specific evaluations such as UPC related to the containment Equipment Hatch (E/H) with 4 bolts, Reactor Coolant System (RCS) Not Intact for severe accident phenomena are desired for realistic evaluation. All POSs are evaluated for their Large Release Frequency (LRF). Some POSs are evaluated conservatively utilizing the at-power models, and other POSs are evaluated in specific analysis. The overall LPSD Level 2 model is evaluated. If the containment E/H and one of the two doors on each of the personal air locks are closed as containment is operable at reduced RCS inventory operation, LRF is expected to be less than 10% of LPSD CDF

  8. A methodology for Level 2 PSA evaluation with consideration of specific features for Low Power Shutdown Probabilistic Safety Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Gab; Seok, Ho [KEPCO-ENC, Yongin (Korea, Republic of)

    2015-05-15

    The primary objective of the Level 2 PSA during Lower Power/Shutdown (LPSD) operation is to provide insights into potential plant vulnerabilities with regard to accident progression. The shutdown risk information can be used to provide the information to develop outage risk management guidelines. The LPSD Level 2 analysis utilizes much of the at-power Level 2 analysis for bounding, conservative treatment of severe accident phenomena. But, for some portions of the analysis including Plant Operational States (POSs), LPSD-specific evaluations such as UPC related to the containment Equipment Hatch (E/H) with 4 bolts, Reactor Coolant System (RCS) Not Intact for severe accident phenomena are desired for realistic evaluation. All POSs are evaluated for their Large Release Frequency (LRF). Some POSs are evaluated conservatively utilizing the at-power models, and other POSs are evaluated in specific analysis. The overall LPSD Level 2 model is evaluated. If the containment E/H and one of the two doors on each of the personal air locks are closed as containment is operable at reduced RCS inventory operation, LRF is expected to be less than 10% of LPSD CDF.

  9. Megahertz-level, high-power picosecond Nd:LuVO4 regenerative amplifier free of period doubling.

    Science.gov (United States)

    Gao, Peng; Lin, Hua; Li, Jinfeng; Guo, Jie; Yu, Haohai; Zhang, Huaijin; Liang, Xiaoyan

    2016-06-27

    We report on a high repetition rate, high-power picosecond Nd:LuVO4 regenerative amplifier. Period doubling caused energy instability was eliminated at megahertz-level repetition rate with the modified seeding source. A multi-pass cell was used to improve the seed pulse energy to achieve complete suppression of the onset of bifurcation. At a maximum repetition rate of 1.43 MHz, the system produced 7.0-ps-long pulses with an average output power of 25.1 W, corresponding to a pulse energy of 17.6 μJ. At 100 kHz, the pulse energy increased to 205 μJ with an average power of 20.5 W. Moreover, the injected pulses with pulse duration of 5.1 ps broadened to 8.9 ps because of gain narrowing in the amplifier. PMID:27410559

  10. A low-power and small-area column-level ADC for high frame-rate CMOS pixel sensor

    International Nuclear Information System (INIS)

    CMOS pixel sensors (CPS) have demonstrated performances meeting the specifications of the International Linear Collider (ILC) vertex detector (VTX). This paper presents a low-power and small-area 4-bit column-level analog-to-digital converter (ADC) for CMOS pixel sensors. The ADC employs a self-timed trigger and completes the conversion by performing a multi-bit/step approximation. As in the outer layers of the ILC vertex detector hit density is of the order of a few per thousand, in order to reduce power consumption, the ADC is designed to work in two modes: active mode and idle mode. The ADC is fabricated in a 0.35 μm CMOS process with a pixel pitch of 35 μm. It is implemented with 48 columns in a sensor prototype. Each column ADC covers an area of 35 ×545 μm2. The measured temporal noise and Fixed Pattern Noise (FPN) are 0.96 mV and 0.40 mV, respectively. The power consumption, for a 3 V supply and 6.25 MS/s sampling rate, is 486 μW during idle time, which is by far the most frequently employed one. This value rises to 714 μW in the case of the active mode. The measured differential nonlinearity (DNL) and integral nonlinearity (INL) are 0.49/−0.28 LSB and 0.29/−0.20 LSB, respectively. - Highlights: • CMOS sensor integrated with column-level ADC is proposed for ILC VTX outer layers. • A low-power and small-area column-level ADC for high frame-rate CPS is presented. • The test results demonstrate the power and area efficiency. • The architecture is suitable for the outer layer CMOS sensors

  11. A low-power and small-area column-level ADC for high frame-rate CMOS pixel sensor

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, L., E-mail: liang.zhang@iphc.cnrs.fr [School of Physics, Key Laboratory of Particle Physics and Particle Irradiation, Shandong University, 250100 Jinan (China); Institut Pluridisciplinaire Hubert Curien, University of Strasbourg, CNRS/IN2P3/UDS, 23 rue du loess, BP 28, 67037 Strasbourg (France); Morel, F.; Hu-Guo, C.; Hu, Y. [Institut Pluridisciplinaire Hubert Curien, University of Strasbourg, CNRS/IN2P3/UDS, 23 rue du loess, BP 28, 67037 Strasbourg (France)

    2014-07-01

    CMOS pixel sensors (CPS) have demonstrated performances meeting the specifications of the International Linear Collider (ILC) vertex detector (VTX). This paper presents a low-power and small-area 4-bit column-level analog-to-digital converter (ADC) for CMOS pixel sensors. The ADC employs a self-timed trigger and completes the conversion by performing a multi-bit/step approximation. As in the outer layers of the ILC vertex detector hit density is of the order of a few per thousand, in order to reduce power consumption, the ADC is designed to work in two modes: active mode and idle mode. The ADC is fabricated in a 0.35 μm CMOS process with a pixel pitch of 35 μm. It is implemented with 48 columns in a sensor prototype. Each column ADC covers an area of 35 ×545 μm{sup 2}. The measured temporal noise and Fixed Pattern Noise (FPN) are 0.96 mV and 0.40 mV, respectively. The power consumption, for a 3 V supply and 6.25 MS/s sampling rate, is 486 μW during idle time, which is by far the most frequently employed one. This value rises to 714 μW in the case of the active mode. The measured differential nonlinearity (DNL) and integral nonlinearity (INL) are 0.49/−0.28 LSB and 0.29/−0.20 LSB, respectively. - Highlights: • CMOS sensor integrated with column-level ADC is proposed for ILC VTX outer layers. • A low-power and small-area column-level ADC for high frame-rate CPS is presented. • The test results demonstrate the power and area efficiency. • The architecture is suitable for the outer layer CMOS sensors.

  12. Saturated Adaptive Output-Feedback Power-Level Control for Modular High Temperature Gas-Cooled Reactors

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2014-11-01

    Full Text Available Small modular reactors (SMRs are those nuclear fission reactors with electrical output powers of less than 300 MWe. Due to its inherent safety features, the modular high temperature gas-cooled reactor (MHTGR has been seen as one of the best candidates for building SMR-based nuclear plants with high safety-level and economical competitive power. Power-level control is crucial in providing grid-appropriation for all types of SMRs. Usually, there exists nonlinearity, parameter uncertainty and control input saturation in the SMR-based plant dynamics. Motivated by this, a novel saturated adaptive output-feedback power-level control of the MHTGR is proposed in this paper. This newly-built control law has the virtues of having relatively neat form, of being strong adaptive to parameter uncertainty and of being able to compensate control input saturation, which are given by constructing Lyapunov functions based upon the shifted-ectropies of neutron kinetics and reactor thermal-hydraulics, giving an online tuning algorithm for the controller parameters and proposing a control input saturation compensator respectively. It is proved theoretically that input-to-state stability (ISS can be guaranteed for the corresponding closed-loop system. In order to verify the theoretical results, this new control strategy is then applied to the large-range power maneuvering control for the MHTGR of the HTR-PM plant. Numerical simulation results show not only the relationship between regulating performance and control input saturation bound but also the feasibility of applying this saturated adaptive control law practically.

  13. Photon pair generation from compact silicon microring resonators using microwatt-level pump powers

    CERN Document Server

    Savanier, Marc; Mookherjea, Shayan

    2015-01-01

    Microring resonators made from silicon, using deep ultraviolet lithography fabrication processes which are scalable and cost-effective, are becoming a popular microscale device format for generating photon pairs at telecommunications wavelengths at room temperature. In compact devices with a footprint less than $5\\times 10^{-4}$ mm$^2$, we demonstrate pair generation using only a few microwatts of average pump power. We discuss the role played by important parameters such as the loss, group-velocity dispersion and the ring-waveguide coupling coefficient in finding the optimum operating point for silicon microring pair generation. Such small devices and low pump power requirements could be beneficial for future scaled-up architectures with many pair-generation devices on the same chip, which will be required to create quasi-deterministic pure single photon sources from inherently statistical processes such as spontaneous four-wave mixing.

  14. Market oriented and rational use of energy and power. Level of competence and need of skill

    International Nuclear Information System (INIS)

    This report surveys the existing research and development (R and D) skill in Norway in the field of ''Market oriented and rational use of energy and power''. The need for skills upgrading and future R and D is discussed. Four areas for R and D are identified as especially important: (1) external conditions, (2) end user behavior, (3) the interplay of all issues related to the end user's competence, and (4) information and communication technology

  15. The level of residual dispersion variation and the power of differential expression tests for RNA-Seq data.

    Directory of Open Access Journals (Sweden)

    Gu Mi

    Full Text Available RNA-Sequencing (RNA-Seq has been widely adopted for quantifying gene expression changes in comparative transcriptome analysis. For detecting differentially expressed genes, a variety of statistical methods based on the negative binomial (NB distribution have been proposed. These methods differ in the ways they handle the NB nuisance parameters (i.e., the dispersion parameters associated with each gene to save power, such as by using a dispersion model to exploit an apparent relationship between the dispersion parameter and the NB mean. Presumably, dispersion models with fewer parameters will result in greater power if the models are correct, but will produce misleading conclusions if not. This paper investigates this power and robustness trade-off by assessing rates of identifying true differential expression using the various methods under realistic assumptions about NB dispersion parameters. Our results indicate that the relative performances of the different methods are closely related to the level of dispersion variation unexplained by the dispersion model. We propose a simple statistic to quantify the level of residual dispersion variation from a fitted dispersion model and show that the magnitude of this statistic gives hints about whether and how much we can gain statistical power by a dispersion-modeling approach.

  16. The level of residual dispersion variation and the power of differential expression tests for RNA-Seq data.

    Science.gov (United States)

    Mi, Gu; Di, Yanming

    2015-01-01

    RNA-Sequencing (RNA-Seq) has been widely adopted for quantifying gene expression changes in comparative transcriptome analysis. For detecting differentially expressed genes, a variety of statistical methods based on the negative binomial (NB) distribution have been proposed. These methods differ in the ways they handle the NB nuisance parameters (i.e., the dispersion parameters associated with each gene) to save power, such as by using a dispersion model to exploit an apparent relationship between the dispersion parameter and the NB mean. Presumably, dispersion models with fewer parameters will result in greater power if the models are correct, but will produce misleading conclusions if not. This paper investigates this power and robustness trade-off by assessing rates of identifying true differential expression using the various methods under realistic assumptions about NB dispersion parameters. Our results indicate that the relative performances of the different methods are closely related to the level of dispersion variation unexplained by the dispersion model. We propose a simple statistic to quantify the level of residual dispersion variation from a fitted dispersion model and show that the magnitude of this statistic gives hints about whether and how much we can gain statistical power by a dispersion-modeling approach. PMID:25849826

  17. Obesity is not associated with increased knee joint torque and power during level walking.

    Science.gov (United States)

    DeVita, Paul; Hortobágyi, Tibor

    2003-09-01

    While it is widely speculated that obesity causes increased loads on the knee leading to joint degeneration, this concept is untested. The purpose of the study was to identify the effects of obesity on lower extremity joint kinetics and energetics during walking. Twenty-one obese adults were tested at self-selected (1.29m/s) and standard speeds (1.50m/s) and 18 lean adults were tested at the standard speed. Motion analysis and force platform data were combined to calculate joint torques and powers during the stance phase of walking. Obese participants were more erect with 12% less knee flexion and 11% more ankle plantarflexion in self-selected compared to standard speeds (both pKnee and ankle torques were 17% and 11% higher (pknee work and positive ankle work were 68% and 11% higher (ppowers were statistically identical at the hip and knee but were 88% and 61% higher (both pknee torque and power at their self-selected walking speed and equal knee torque and power while walking at the same speed as lean individuals. We propose that the ability to reorganize neuromuscular function during gait may enable some obese individuals to maintain skeletal health of the knee joint and this ability may also be a more accurate risk indicator for knee osteoarthritis than body weight.

  18. Is the level of financial sector development a key determinant of private investment in the power sector ?

    OpenAIRE

    Gasmi, Farid; Lika, Ba; Noumba Um, Paul

    2010-01-01

    TThis paper seeks to assess the extent to which a country’s overall level of development and that of its financial sector, in particular, are factors that attract private capital into infrastructure projects. The authors investigate these effects in a 1990–2007 dataset on the power sector in 37 developing countries. The results suggest that economic growth is a key determinant of private investors’ investment in infrastructure projects, and that investors tend to take countries’ governance...

  19. Stand by Leakage Power Reduction in Nanoscale Static CMOS VLSI Multiplier Circuits Using Self Adjustable Voltage Level Circuit

    OpenAIRE

    Deeprose Subedi; Eugene John

    2012-01-01

    In this paper, we performed the comparative analysis of stand-by leakage (when the circuit is idle), delay and dynamic power (when the circuit switches) of the three different parallel digital multiplier circuits implemented with two adder modules and Self Adjustable Voltage level circuit (SVL). The adder modules chosen were 28 transistor-conventional CMOS adder and 10 transistor- Static Energy Recovery CMOS adder (SERF) circuits. The multiplier modules chosen were 4Bits Array, 4 bits Carry S...

  20. Effect of Carbohydrate Solutions with Different level of Sugar on Average Anaerobic power and Fatigue index of karate Players

    OpenAIRE

    AMINIAN, Ensiyeh

    2015-01-01

    Abstract. Main aim of this research was investigating effect of carbohydrate solutions with different level of sager on average anaerobic power and fatigue index of karate players. Statistical sample of this research was 72 karate players of Khorasa Razavi province and 48 people were selected randomly. Average age, weight, height, and BMI were measures Average age of athletes was 22.23, average height 175cm and average weight 72.77. We used frequency distribution tables and indexes of the cen...

  1. Unified System-Level Modeling of Intermittent Renewable Energy Sources and Energy Storage for Power System Operation

    OpenAIRE

    Heussen, Kai; Koch, Stephan; Ulbig, Andreas; Andersson, Goran

    2011-01-01

    The system-level consideration of inter- mittent renewable energy sources and small-scale en- ergy storage in power systems remains a challenge as either type is incompatible with traditional operation concepts. Non-controllability and energy-constraints are still considered contingent cases in market-based operation. The design of operation strategies for up to 100 % renewable energy systems requires an explicit consideration of non-dispatchable generation and stor- age capacities, as well a...

  2. Mean sea level and change in the hydrological regime off Loviisa power plant around the year 2050

    International Nuclear Information System (INIS)

    On the request of Imatran Voima Oy, the Institute of Marine Research has made an estimate on the future sea level off Loviisa Power Plant. The estimate is based on observationsof mean sea level in the Gulf of Finland. The stations used are Helsinki (observations since 1904) and Hamina (observations since 1928). A litterature review was made in order to estimate impact of climate change on environmental conditions. The results presented are mainly based on various estimates of meterorological Global Circulation Models (GCM). Their usefulness in the connection is briefly discussed

  3. Comparison of anthropometry, upper-body strength, and lower-body power characteristics in different levels of Australian football players.

    Science.gov (United States)

    Bilsborough, Johann C; Greenway, Kate G; Opar, David A; Livingstone, Steuart G; Cordy, Justin T; Bird, Stephen R; Coutts, Aaron J

    2015-03-01

    The aim of this study was to compare the anthropometry, upper-body strength, and lower-body power characteristics in elite junior, sub-elite senior, and elite senior Australian Football (AF) players. Nineteen experienced elite senior (≥4 years Australian Football League [AFL] experience), 27 inexperienced elite senior (Football players' FFSTM are different between playing levels, which are likely because of training and partly explain the observed differences in performance between playing levels highlighting the importance of optimizing FFSTM in young players.

  4. Physical activity level, musculoskeletal fitness,balance, strength and power performance in older adults

    OpenAIRE

    Lohne-Seiler, Hilde

    2015-01-01

    The link between physical activity and prevention of disease, maintenance of independence, and improved quality of life in older adults is supported by strong evidence. However, there is a lack of data on population levels where physical activity level has been measured objectively in association with self-reported health, musculoskeletal fitness and balance variables in older men and women. Also, little is known about the functional adaptive responses of older adults to pow...

  5. Superradiance on the Landau levels and the problem of power of decameter radiation of Jupiter

    OpenAIRE

    Fomin, P. I.; Fomina, A. P.; Malnev, V. N.

    2002-01-01

    We determine the conditions of formation of spontaneous polarization phase transition to the superradiance regime in the inverted system of nonrelativistic electrons on equidistant Landau levels in rarefied magnetized plasma. The possibility of realization of such conditions in the lower Jupiter magnetosphere is shown. The effect of cyclotron superradiance on the Landau levels gives a key to interpretation of the nature of superpower radioemission of the Jupiter-Io system.

  6. The application of power-to-gas, pumped hydro storage and compressed air energy storage in an electricity system at different wind power penetration levels

    International Nuclear Information System (INIS)

    Many countries worldwide have committed themselves to reducing the rate in which they emit greenhouse gasses. These emissions are the major driver behind human induced global warming. Renewable electricity implementation is one way of reducing the amount of greenhouse gas emissions. However, this transition is also accompanied by some problems. The intermittency of renewables demands for a more flexible electricity system. In existing electricity systems this lack of flexibility already leads to load balancing issues increasing costs and threatening energy security. Large scale storage facilities could provide the needed flexibility. This paper focuses on the economic and environmental system consequences of the application of power-to-gas, pumped hydro storage and compressed air energy storage in an electricity system at different wind power penetration levels. The study shows that the application of large scale energy storage techniques results in economic costs reducing effects on the electricity system. These are highest for pumped hydro storage, followed by the cost reducing effects of compressed air energy storage and power-to-gas. The impact on the fuel use and the emissions is less obvious. In some scenarios, the application of storage even resulted in an increase of the fuel use and the emissions. - Highlights: • We studied the effects of adding three storage techniques to an electricity system. • We modelled: Power-to-gas, pumped hydro storage and compressed air energy storage. • Storage is used for optimizing the operational costs of the electricity system. • The economic system benefits were highest when applying pumped hydro storage. • The application of storage not always resulted in environmental system benefits

  7. Design of kW level picosecond compressor of pump pulses for high power OPCPA

    Science.gov (United States)

    Bakule, Pavel; Novák, Jakub; Kramer, Daniel; Strkula, Petr; Novák, Miroslav; Hřebíček, Jan; Koutris, Efstratios; Zervos, Charalampos; Baše, Radek; Batysta, František; Hubka, Zbyněk.; Green, Jonathan T.; Rus, Bedřich

    2013-05-01

    We present a design of a high average power vacuum compressor unit for 1 kHz repetition rate pump laser operating at 1030 nm. The unit comprises two compressors and two SHG units located in a common vacuum vessel. Both compressors are designed with GDD of -270.5 ps2 for compressing high energy, 1J, 500 ps pulses to 1.5 ps duration with efficiency that exceeds 88.5%. We also considered the feasibility of high efficiency, average power conversion to 515 nm in a range of nonlinear crystals in vacuum. The calculated temperature profiles in large aperture crystals are compared with temperature acceptance bandwidths for the second harmonic generation. It is concluded that in LBO and YCOB crystals the conversion efficiency can exceed 60%, thus allowing generation of 1 kHz train of 1.5 ps pulses at 515 nm with energy exceeding 0.5 J that will be used for pumping the high energy amplifier stages of a femtosecond OPCPA system.

  8. 考虑风剪切的1.3MW风力机整机三维定常流动数值研究%Numerical Study on 3D Steady Flow of a 1.3 MW Wind Turbine Considering Wind Shear Factor

    Institute of Scientific and Technical Information of China (English)

    韩中合; 李引; 季剑

    2011-01-01

    分别采用均匀风和剪切风对1.3 MW失速调节风力机整机在8 m/s和13 m/s来流风速下的绕流流场进行全三维定常数值模拟。根据模拟结果分析叶片不同截面的压力系数分布、沿叶展方向的功率分布、风轮三维流场细节、风轮下游不同距离处的静压分布和二维相对速度矢量分布情况。结果表明:剪切风下,风力机功率计算值与设计值吻合较好;在靠近叶根处,适当地减小有效攻角可提高翼型气动性能,选择适应较大攻角的翼型,可以提高叶根处的输出功率;在靠近叶尖的部位,适当增加有效攻角,同时选择适应小攻角的翼型可以提高叶尖处的输出功率;在叶根部位,发生了明显的流动分离;塔架与轮毂所在位置的下游尾迹处产生的漩涡和干扰要远远大于叶轮面其他部位。%A numerical simulation on 3D steady flow around a 1.3 MW stall-regulated wind turbine was carried out at wind speeds of 8 m/s and 13 m/s respectively under uniform and shear wind conditions,based on which following factors were analyzed,such as the pressure coefficient distribution at different sections,the loading distribution along the span of rotor blade,the 3D flow detail of wind rotor,the static pressure distribution and the 2D velocity vector distribution at different sections in the z-direction.Results show that the simulated data of turbine power agree well with that of the design under shear wind conditions;the power output at blade root can be increased by properly reducing the effective attack angle to improve the aerodynamic performance or by choosing an airfoil with a large attack angle for the root area;whereas at the blade tip,the power output can be increased by raising the effective attack angle properly or by choosing an airfoil with a smaller attack angle;obvious flow separation occurs at blade root;the wake vortex and its disturbance in the downstream of tower and hub are much larger than those in

  9. The embedded pressurizer water-level control system of nuclear power plant

    International Nuclear Information System (INIS)

    Based on the analysis of the structure, the function and the running theory of the analog pressurizer water-level control system (APWLCS), the study of the digitization APWLCS is performed in this paper. The PWLCS was obtained based on a mature commercial SBC, considering the conversions of Digital/Analog and Analog/Digital and the control algorithms, and constituted a closed-loop with the pressurizer water-level simulate model to run the system. The control system was checked by the dummy apparatus, and it proved that the system has achieved and exceeded the original analog control system in function and performance. (authors)

  10. Reducing radiation levels at boiling water reactors of a commercial nuclear power plant fleet

    International Nuclear Information System (INIS)

    Boiling Water Reactors (BWRs) have suffered from high radiation fields in the primary loop, typically measured by the 'BRAC' (BWR Radiation Level Assessment and Control) reactor recirculation system (RRS) dose rates. Reactor water chemistry and activated corrosion product measurements are important in understanding changes in radiation fields in components and systems of a BWR. Several studies have been conducted at Exelon Nuclear's 14 BWRs in order to understand more fully the cause and effect relationships between reactor water radioactive species and radiation levels. Various radiation control strategies are utilized to control and reduce radiation levels. The proper measurement of radioactive soluble and insoluble species is a critical component in understanding radiation fields. Other factors that impact radiation fields include: noble metal applications; hydrogen injection; zinc addition; chemistry results; cobalt source term; fuel design and operation. Chemistry and radiation field trending and projections are important tools that assist in assessing the potential for increased radiation fields and aiding outage planning efforts, including techniques to minimize outage dose. This paper will present the findings from various studies and predictor tools as well as provide recommendations for continued research efforts in this field. Current plant data will be shared on reactor water radioactive species, plant radiation levels, zinc addition amounts and other chemistry controls. (author)

  11. Modelling of the Multi-Level STATCOM for Harmonic Stability Studies in Offshore Wind Power Plants

    DEFF Research Database (Denmark)

    Glasdam, Jakob Bærholm; Bak, Claus Leth; Hjerrild, Jesper;

    2017-01-01

    The large number of semi-conductors in the modular multi-level cascaded converters (MMCCs) possesses significant computational challenges in the electromagnetic transient programs (EMTPs). An accurate Thévenin equivalenthas previously been devised, improving the simulation speed of the half...

  12. Combining gigawatt level X-band high power microwave beams with an overmoded circular waveguide diplexer

    International Nuclear Information System (INIS)

    The high power microwave (HPM) beam combining results at X-band with an overmoded waveguide diplexer are presented. As the key device for the beam combining experiments, the diplexer is designed, fabricated, and tested. Then the beam combining experiments under short and long pulses are performed at HPM source, respectively. The experiment results reveal that short and long pulse HPM beams have been successfully operated without microwave breakdown at 3-GW with pulse duration of 25 ns and 1.3-GW with pulse duration of 96 ns. According to the experiments, conservative breakdown thresholds for the diplexer are concluded to be 800 kV/cm and 550 kV/cm, respectively, under the short and long pulse HPM conditions

  13. DC-pass filter design with notch filters superposition for CPW rectenna at low power level

    Science.gov (United States)

    Rivière, J.; Douyère, A.; Alicalapa, F.; Luk, J.-D. Lan Sun

    2016-03-01

    In this paper the challenging coplanar waveguide direct current (DC) pass filter is designed, analysed, fabricated and measured. As the ground plane and the conductive line are etched on the same plane, this technology allows the connection of series and shunt elements to the active devices without via holes through the substrate. Indeed, this study presents the first step in the optimization of a complete rectenna in coplanar waveguide (CPW) technology: key element of a radio frequency (RF) energy harvesting system. The measurement of the proposed filter shows good performance in the rejection of F0=2.45 GHz and F1=4.9 GHz. Additionally, a harmonic balance (HB) simulation of the complete rectenna is performed and shows a maximum RF-to-DC conversion efficiency of 37% with the studied DC-pass filter for an input power of 10 µW at 2.45 GHz.

  14. Assessment of mass transfer and mixing in rigid lab-scale disposable bioreactors at low power input levels.

    Science.gov (United States)

    van Eikenhorst, Gerco; Thomassen, Yvonne E; van der Pol, Leo A; Bakker, Wilfried A M

    2014-01-01

    Mass transfer, mixing times and power consumption were measured in rigid disposable stirred tank bioreactors and compared to those of a traditional glass bioreactor. The volumetric mass transfer coefficient and mixing times are usually determined at high agitation speeds in combination with sparged aeration as used for single cell suspension and most bacterial cultures. In contrast, here low agitation speeds combined with headspace aeration were applied. These settings are generally used for cultivation of mammalian cells growing adherent to microcarriers. The rigid disposable vessels showed similar engineering characteristics compared to a traditional glass bioreactor. On the basis of the presented results appropriate settings for adherent cell culture, normally operated at a maximum power input level of 5 W m(-3) , can be selected. Depending on the disposable bioreactor used, a stirrer speed ranging from 38 to 147 rpm will result in such a power input of 5 W m(-3) . This power input will mix the fluid to a degree of 95% in 22 ± 1 s and produce a volumetric mass transfer coefficient of 0.46 ± 0.07 h(-1) . PMID:25139070

  15. A three-dimensional electret-based micro power generator for low-level ambient vibrational energy harvesting

    Science.gov (United States)

    Tao, Kai; Liu, Shuwei; Woh Lye, Sun; Miao, Jianmin; Hu, Xiao

    2014-06-01

    A novel three-dimensional (3D) electret-based micro power generator with multiple vibration modes has been developed, which is capable of converting low-level ambient kinetic energy to electrical energy. The device is based on a rotational symmetrical resonator which consists of a movable disc-shaped seismic mass suspended by three sets of spiral springs. Experimental analysis shows that the proposed generator operates at an out-of-plane direction at mode I of 66 Hz and two in-plane directions at mode II of 75 Hz and mode III of 78.5 Hz with a phase difference of about 90°. A corona localized charging method is also proposed that employs a shadow mask and multiple discharge needles for the production of micro-sized electret array. From tests conducted at an acceleration of 0.05 g, the prototype can generate a maximum power of 4.8 nW, 0.67 nW and 1.2 nW at vibration modes of I, II and III, respectively. These values correspond to the normalized power densities of 16 µW cm-3 g-2, 2.2 µW cm-3 g-2 and 4 µW cm-3 g-2, respectively. The results show that the generator can potentially offer an intriguing alternative for scavenging low-level ambient energy from 3D vibration sources.

  16. Estimation of Radiofrequency Power Leakage from Microwave Ovens for Dosimetric Assessment at Nonionizing Radiation Exposure Levels

    Directory of Open Access Journals (Sweden)

    Peio Lopez-Iturri

    2015-01-01

    Full Text Available The electromagnetic field leakage levels of nonionizing radiation from a microwave oven have been estimated within a complex indoor scenario. By employing a hybrid simulation technique, based on coupling full wave simulation with an in-house developed deterministic 3D ray launching code, estimations of the observed electric field values can be obtained for the complete indoor scenario. The microwave oven can be modeled as a time- and frequency-dependent radiating source, in which leakage, basically from the microwave oven door, is propagated along the complete indoor scenario interacting with all of the elements present in it. This method can be of aid in order to assess the impact of such devices on expected exposure levels, allowing adequate minimization strategies such as optimal location to be applied.

  17. Geometrical Optimization for Improved Power Capture of Multi-Level Overtopping Based Wave Energy Converters

    DEFF Research Database (Denmark)

    Margheritini, Lucia; Victor, L.; Kofoed, Jens Peter;

    2009-01-01

    In multi-level wave energy converters the water from incoming waves is stored in reservoirs one on top of the other. Prevision formula for the overtopping flow rates in the individual reservoirs is fundamental for dimensioning correctly the turbines and optimizing the device. Having a number...... words, the opening between two consecutive reservoirs. 13 different geometries have been tested in 2D irregular waves and a new formulation for prediction of overtopping in multilevel structures is presented....

  18. Modelling and control of a seven level NPC voltage source inverter. Application to high power induction machine drive

    Science.gov (United States)

    Gheraia, H.; Berkouk, E. M.; Manesse, G.

    2001-08-01

    In this paper, we study a new kind of continuous-alternating converters: a seven-level neutral point clamping (NPC) voltage source inverter (VSI). We propose this inverter for applications in high voltage and high power fields. In the first part, we develop the knowledge and the control models of this inverter using the connections functions of the semi-conductors. After that, we present two pulse width modulation (PWM) algorithms to control this converter using its control model. We propose these algorithms for digital implementation. This multilevel inverter is associated to the induction machine. The performances obtained are full of promise to use it in the high voltage and high power fields of electrical traction.

  19. System-Level Power Optimization for a ΣΔ D/A Converter for Hearing-Aid Application

    DEFF Research Database (Denmark)

    Pracný, Peter; Jørgensen, Ivan Harald Holger; Bruun, Erik

    2013-01-01

    This paper deals with a system-level optimization of a back-end of audio signal processing chain for hearing-aids, including a sigma-delta modulator digital-to-analog converter (DAC) and a Class D power amplifier. Compared to other stateof-the-art designs dealing with sigma-delta modulator design...... for audio applications we take the maximum gain of the modulator noise transfer function (NTF) as a design parameter. By increasing the maximum NTF gain the cutoff frequency of modulator loop filter is increased which lowers the in-band quantization noise but also lowers the maximum stable amplitude (MSA...... hearing-aid audio back-end system resulting in less hardware and power consumption in the interpolation filter, in the sigma-delta modulator and reduced switching rate of the Class D output stage....

  20. LCL filter design for three-phase two-level power factor correction using line impedance stabilization network

    DEFF Research Database (Denmark)

    Kouchaki, Alireza; Nymand, Morten

    2016-01-01

    with unknown grid impedance at high frequency, simplify the model of the filter, and provide repetitive measurements. In this paper, all the filter parameters are derived with analyzing the behavior of the converter at high frequency with presence of LISN impedance. The minimum required filter capacitor......This paper presents LCL filter design method for three-phase two-level power factor correction (PFC) using line impedance stabilization network (LISN). A straightforward LCL filter design along with variation in grid impedance is not simply achievable and inevitably lead to an iterative solution...... for filter. By introducing of fast power switches for PFC applications such as silicon-carbide, major current harmonics around the switching frequency drops in the region that LISN can actively provide well-defined impedance for measuring the harmonics (i.e. 9 kHz- 30MHz). Therefore, LISN can be replaced...

  1. Modelling and control of a seven level NPC voltage source inverter. Application to high power induction machine drive

    Energy Technology Data Exchange (ETDEWEB)

    Gheraia, H.; Berkouk, E.M. [ENP, Alger (Algeria). Lab. de Commande des Processus; Manesse, G. [CNAM-Paris (France). Lab. d' Electricite Industrielle

    2001-08-01

    In this paper, we study a new kind of continuous-alternating converters: a seven-level neutral point clamping (NPC) voltage source inverter (VSI). We propose this inverter for applications in high voltage and high power fields. In the first part, we develop the knowledge and the control models of this inverter using the connections functions of the semi-conductors. After that, we present two pulse width modulation (PWM) algorithms to control this converter using its control model. We propose these algorithms for digital implementation. This multilevel inverter is associated to the induction machine. The performances obtained are full of promise to use it in the high voltage and high power fields of electrical traction. (orig.)

  2. Assay of long-lived radionuclides in low-level wastes from power reactors

    International Nuclear Information System (INIS)

    The 10 CFR Part 61 waste classification system includes several nuclides which are difficult to assay without expensive radiochemical methods. In order for waste generators to classify wastes practically, NRC Staff has recommended the use of correlation factors to scale the difficult-to-measure nuclides with nuclides which can be measured more easily (i.e., gamma emitters such as 60Co or 137Cs). In this study, Science Applications International Corporation (SAIC) performed complete radiochemical assays for all the 10 CFR Part 61 waste classification nuclides on over 100 samples. These data, along with almost 800 other samples in the SAIC data base, were used to assess the validity of correlation factors suggested for use in nuclear power plant wastes. Specific generic correlation factors are recommended with other approaches to correlate nuclides for which generic scaling factors are not defensible. The primary nuclide correlations studied were 14C, 55Fe, 59Ni, 63Ni, and 94Nb, with 60Co; 90Sr, 99Tc, 129I, 135Cs, and /sup 239, 240/Pu with 137Cs; 238Pu, /sup 239, 240/Pu, 241Pu, 241Am, 242Cm, and /sup 243, 244/Cm with 144Ce; and 238Pu, 241Pu, 241Am, 242Cm and /sup 243, 244/Cm with /sup 239, 240/Pu

  3. Daytime edema levels with plus powered low and high water content hydrogel contact lenses.

    Science.gov (United States)

    La Hood, D

    1991-11-01

    Eleven unadapted contact lens wearers wore a high (74%) water content hydrogel lens (Permaflex, CooperVision) of oxygen transmissibility Dk/Lav 14 x 10(-9) in one eye and a low (43%) water content hydrogel lens (Aquaflex Superthin) of Dk/Lav 4 x 10(-9) in the other eye under open-eye conditions for 8 h. After 8 h, average corneal edema for the lower water content lens was 7.9 +/- 2.6%, which was significantly more than that for the higher water content lens, 1.7 +/- 1.6%. Significantly fewer corneal striae and folds were also seen in the eyes wearing the higher water content lens. Subjective ratings of lens comfort were significantly better for the higher water content lens. Low water content positive power hydrogel lenses of the thicknesses used in this study place unacceptable hypoxic stress on the cornea and therefore should not be used for all-day wear. PMID:1766650

  4. Assessment of the Current Level of Automation in the Manufacture of Fuel Cell Systems for Combined Heat and Power Applications

    Energy Technology Data Exchange (ETDEWEB)

    Ulsh, M.; Wheeler, D.; Protopappas, P.

    2011-08-01

    The U.S. Department of Energy (DOE) is interested in supporting manufacturing research and development (R&D) for fuel cell systems in the 10-1,000 kilowatt (kW) power range relevant to stationary and distributed combined heat and power applications, with the intent to reduce manufacturing costs and increase production throughput. To assist in future decision-making, DOE requested that the National Renewable Energy Laboratory (NREL) provide a baseline understanding of the current levels of adoption of automation in manufacturing processes and flow, as well as of continuous processes. NREL identified and visited or interviewed key manufacturers, universities, and laboratories relevant to the study using a standard questionnaire. The questionnaire covered the current level of vertical integration, the importance of quality control developments for automation, the current level of automation and source of automation design, critical balance of plant issues, potential for continuous cell manufacturing, key manufacturing steps or processes that would benefit from DOE support for manufacturing R&D, the potential for cell or stack design changes to support automation, and the relationship between production volume and decisions on automation.

  5. INFLUENCES OF THE PURCHASING POWER CHANGE ON THE EVOLUTION OF THE AGROALIMETARY MARKETS ON EUROPEAN UNION LEVEL

    Directory of Open Access Journals (Sweden)

    Laura Catalina Timiras

    2014-01-01

    Full Text Available This paper aims to identify the manifested connection between the dynamics of the population purchasing power and the dynamic of agroalimentary markets in general as well as by product types on European Union level. Based on the last data supplied by Eurostat 2013, using the specific methods for studying the correlations, we have detected that increases and decreases of the purchasing power generated similar changes on agroalimentary markets level from the point of view of achieved sales in most of the poorer countries of the European Union, but not in those states which got beyond the average gross domestic product per capita of the European Union. This relationship has been noticed only on the agroalimentary markets as a whole (respectively on the amounts spent by the population for purchasing agroalimentary goods, beverages and tobacco, but not on the level of markets of various types of product (“meat and meat products”, “fruit and vegetables”, “dairy produce, eggs and edible oils and fats”, “beverages”, “sugar and chocolate and sugar confectionery”, “tobacco products”.

  6. Human reliability analysis for level-1 PSA study of Indian nuclear power plants

    International Nuclear Information System (INIS)

    Full text: Probabilistic safety studies show that human actions contribute significantly to overall safety in nuclear power plants (NPPs). The contribution of potential human errors to risk is quantitatively assessed in a human reliability analysis (HRA) study in terms of human error probabilities (HEPs) and used to arrive at ways to improve human performance. HRA is thus integral to a probabilistic safety assessment (PSA). In order to handle various emergency conditions such as process or support system failure, which can arise in the plant, a set of emergency operating procedures (EOPs) are developed and provided to NPP operators. Operators are trained to diagnose the event that has occurred and then select and carry out the EOP. Human interaction involved in the execution of an EOP plays an important role in determining the course of an event. If errors occur and operators fail to recover from them, the situation can get aggravated and even result in the event turning into an accident. It is therefore essential to carry out a HRA study for EOPs and determine the human interactions that are the dominant contributors to risk. This would enable designers to implement necessary modifications in procedures and/or develop operator aids to support reliable human performance. This paper first discusses the HRA study carried out for the EOP for station blackout (SBO) event in an Indian pressurised heavy water reactor (IPHWR) and then a study for active process water system (APWS) failure event in advanced heavy water reactor (AHWR). Human reliability quantification has been done using accident sequence evaluation programme (ASEP) which is an accident sequence, data driven HRA technique. The HRA covers event detection and diagnosis and post-diagnosis actions involved. The details of human reliability assessment are given in the paper

  7. A new method to estimate implied equity risk premiums: The level of premiums and their explanatory power

    OpenAIRE

    Lindroos, Mikko

    2013-01-01

    The main objective of the study is to determine the level of implied equity risk premiums from two models and to analyse their explanatory power in terms of future realized equity risk premiums. The paper studies a new method to estimate implied premiums and validates the results by a comparison to an established model. Luoma and Sahlström (2009) presented their model to estimate implied equity risk premiums by looking at an earn back period calculated from analysts' earnings forecasts, the c...

  8. Radiochemical methodologies applied to determination of zirconium isotopes in low-level waste samples from nuclear power plants

    International Nuclear Information System (INIS)

    The 93Zr determination in low-level radioactive wastes generated at nuclear power plants is an important issue for waste disposal purpose. This paper describes an analytical methodology developed for 93Zr determination based on selective separation using extractive resins associated with inductively coupled plasma mass spectrometry (ICP-MS) and liquid scintillation counting (LSC) measurements. The 93Zr results obtained for waste samples were in a good agreement for both techniques and the detection limits of 0.045 μg L-1 and 0.05 Bq L-1 were obtained for ICP-MS and LSC techniques respectively. (author)

  9. Procedures for conducting probabilistic safety assessments of nuclear power plants (Level 1)

    International Nuclear Information System (INIS)

    This report provides guidance for conducting a Level 1 of probabilistic safety assessment (PSA), that is a PSA concerned with events leading to core damage. The scope of this report is confined to internal initiating events (excluding internal fires and floods). A particular aim is to promote a standardized framework, terminology and form of documentation for PSAs so as to facilitate external review of the results of such studies. The report is divided into the following major sections: management and organization; identification of sources of radioactive releases and accident initiators; accident sequence modelling; data assessment and parameter estimation; accident sequence quantification; documentation of the analysis: display and interpretation of result. 45 refs, 7 figs, 23 tabs

  10. M4D: a powerful tool for structured programming at assembly level for MODCOMP computers

    International Nuclear Information System (INIS)

    Structured programming techniques offer numerous benefits for software designers and form the basis of the current high level languages. However, these techniques are generally not available to assembly programmers. The M4D package was therefore developed for a large project to enable the use of structured programming constructs such as DO.WHILE-ENDDO and IF-ORIF-ORIF...-ELSE-ENDIF in the assembly code for MODCOMP computers. Programs can thus be produced that have clear semantics and are considerably easier to read than normal assembly code, resulting in reduced program development and testing effort, and in improved long-term maintainability of the code. This paper describes the M4D structured programming tool as implemented for MODCOMP'S MAX III and MAX IV assemblers, and illustrates the use of the facility with a number of examples

  11. Minimization program of low-level radioactive waste at nuclear power plants in Taiwan

    International Nuclear Information System (INIS)

    This paper reviews the strategy and source/volume reduction practices of the LLRW minimization program implemented in Taiwan over the past decades. The LLRW minimization program in Taiwan includes LLRW minimization regulation/strategy, source reduction and volume reduction. The Radioactive Waste Management Policy was promulgated by the Executive Yuan on September 16, 1988 and revised on September 2, 1997. In accordance with the policy, radwaste producers shall endeavor to minimize the amounts and volumes of radwaste productions. Several activities of source reduction and volume reduction have already done, such as adapted equipment change to improve the liquid filter performance in radwaste treatment system, good housekeeping and administration control in radiation control area to reduce the dry radwaste generation, a high efficiency solidification technology (HEST) was developed by the Institute of the Nuclear Energy Research (INER) and successfully implemented at the MSNPP, The Volume Reduction Center (VRC) located at the KSNPP site was put in operation. As a result of persistent efforts over the past two decades, the annual solidified radwaste generated has been reduced from a high level at 12,258 drums per year in 1983 to less than 5,000 drums in 1992 and further down to 259 drums in 2007. The amount of annual solidified radwaste generated currently has been significantly reduced to 2% of the peak. In addition, the annual dry radwaste generated has been reduced from a high level at 7,571 drums per year in 1990 to less than 2,125 drums in 2007. The amount of annual dry radwaste generated also has significantly reduced to 28% of the peak. (author)

  12. An ultra-low power self-timed column-level ADC for a CMOS pixel sensor based vertex detector

    Science.gov (United States)

    Zhang, L.; Wang, M.

    2014-11-01

    The International Large Detector (ILD) is a detector concept for the future linear collider experiment. The vertex detector is the key tool to achieve high precision measurements for flavor tagging, which puts stringent requirements on the CMOS pixel sensors. Due to the cooling systems which deteriorate the material budget and increase the multiple scattering, it is important to reduce the power consumption. This paper presents an ultra-low power self-timed column-level ADC for the CMOS pixel sensors, aiming to equip the outer layers of the vertex detector. The ADC was designed to operate in two modes (active and idle) adapted to the low hit density in the outer layers. The architecture employs an enhanced sample-and-hold circuit and a self-timed technique. The total power consumption with a 3-V supply is 225μW during idle mode, which is the most frequent situation. This value rises to 425μW in the case of the active mode. It occupies an area of 35 × 590μm2.

  13. An ultra-low power self-timed column-level ADC for a CMOS pixel sensor based vertex detector

    International Nuclear Information System (INIS)

    The International Large Detector (ILD) is a detector concept for the future linear collider experiment. The vertex detector is the key tool to achieve high precision measurements for flavor tagging, which puts stringent requirements on the CMOS pixel sensors. Due to the cooling systems which deteriorate the material budget and increase the multiple scattering, it is important to reduce the power consumption. This paper presents an ultra-low power self-timed column-level ADC for the CMOS pixel sensors, aiming to equip the outer layers of the vertex detector. The ADC was designed to operate in two modes (active and idle) adapted to the low hit density in the outer layers. The architecture employs an enhanced sample-and-hold circuit and a self-timed technique. The total power consumption with a 3-V supply is 225μW during idle mode, which is the most frequent situation. This value rises to 425μW in the case of the active mode. It occupies an area of 35 × 590μm2

  14. Stand by Leakage Power Reduction in Nanoscale Static CMOS VLSI Multiplier Circuits Using Self Adjustable Voltage Level Circuit

    Directory of Open Access Journals (Sweden)

    Deeprose Subedi

    2012-10-01

    Full Text Available In this paper, we performed the comparative analysis of stand-by leakage (when the circuit is idle, delay and dynamic power (when the circuit switches of the three different parallel digital multiplier circuits implemented with two adder modules and Self Adjustable Voltage level circuit (SVL. The adder modules chosen were 28 transistor-conventional CMOS adder and 10 transistor- Static Energy Recovery CMOS adder (SERF circuits. The multiplier modules chosen were 4Bits Array, 4 bits Carry Save and 4 Bits Baugh Wooley multipliers. At first, the circuits were simulated with adder modules without applying the SVL circuit. And secondly, SVL circuit was incorporated in the adder modules for simulation. In all the multiplier architectures chosen, less standby leakage power was observed being consumed by the SERF adder based multipliers applied with SVL circuit. The stand-by leakage power dissipation is 1.16µwatts in Bits array multiplier with SERF Adder applied with SVL vs. 1.39µwatts in the same multiplier with CMOS28T Adder applied with SVL circuit. It is 1.16µwatts in Carry Save multiplier with SERF Adder applied with SVL vs. 1.4µwatts in the same multiplier with CMOS 28T Adder applied with SVL circuit. It is 1.67µwatts in Baugh Wooley multiplier with SERF Adder applied with SVl circuit vs. 2.74µwatts in the same multiplier with CMOS 28T Adder applied with SVL circuit.

  15. Stand by Leakage Power Reduction in Nanoscale Static CMOS VLSI Multiplier Circuits Using Self Adjustable Voltage Level Circuit

    Directory of Open Access Journals (Sweden)

    Deeprose Subedi

    2012-11-01

    Full Text Available In this paper, we performed the comparative analysis of stand-by leakage (when the circuit is idle, delay and dynamic power (when the circuit switches of the three different parallel digital multiplier circuits implemented with two adder modules and Self Adjustable Voltage level circuit (SVL. The adder modules chosen were 28 transistor-conventional CMOS adder and 10 transistor- Static Energy Recovery CMOS adder (SERF circuits. The multiplier modules chosen were 4Bits Array, 4bits Carry Save and 4Bits Baugh Wooley multipliers. At first, the circuits were simulated with adder modules without applying the SVL circuit. And secondly, SVL circuit was incorporated in the adder modules for simulation. In all the multiplier architectures chosen, less standby leakage power was observed being consumed by the SERF adder based multipliers applied with SVL circuit. The stand-by leakage power dissipation is 1.16µwatts in Bits array multiplier with SERF Adder applied with SVL vs. 1.39µwatts in the same multiplier with CMOS28T Adder applied with SVL circuit. It is 1.16µwatts in Carry Save multiplier with SERF Adder applied with SVL vs. 1.4µwatts in the same multiplier with CMOS 28T Adder applied with SVL circuit. It is 1.67µwatts in Baugh Wooley multiplier with SERF Adder applied with SVl circuit vs. 2.74µwatts in the same multiplier with CMOS 28T Adder applied with SVL circuit.

  16. A low-power and small-area column-level ADC for high frame-rate CMOS pixel sensor

    Science.gov (United States)

    Zhang, L.; Morel, F.; Hu-Guo, C.; Hu, Y.

    2014-07-01

    CMOS pixel sensors (CPS) have demonstrated performances meeting the specifications of the International Linear Collider (ILC) vertex detector (VTX). This paper presents a low-power and small-area 4-bit column-level analog-to-digital converter (ADC) for CMOS pixel sensors. The ADC employs a self-timed trigger and completes the conversion by performing a multi-bit/step approximation. As in the outer layers of the ILC vertex detector hit density is of the order of a few per thousand, in order to reduce power consumption, the ADC is designed to work in two modes: active mode and idle mode. The ADC is fabricated in a 0.35 μm CMOS process with a pixel pitch of 35 μm. It is implemented with 48 columns in a sensor prototype. Each column ADC covers an area of 35 ×545 μm2. The measured temporal noise and Fixed Pattern Noise (FPN) are 0.96 mV and 0.40 mV, respectively. The power consumption, for a 3 V supply and 6.25 MS/s sampling rate, is 486 μW during idle time, which is by far the most frequently employed one. This value rises to 714 μW in the case of the active mode. The measured differential nonlinearity (DNL) and integral nonlinearity (INL) are 0.49/-0.28 LSB and 0.29/-0.20 LSB, respectively.

  17. Direct integration of intensity-level data from Affymetrix and Illumina microarrays improves statistical power for robust reanalysis

    Directory of Open Access Journals (Sweden)

    Turnbull Arran K

    2012-08-01

    Full Text Available Abstract Background Affymetrix GeneChips and Illumina BeadArrays are the most widely used commercial single channel gene expression microarrays. Public data repositories are an extremely valuable resource, providing array-derived gene expression measurements from many thousands of experiments. Unfortunately many of these studies are underpowered and it is desirable to improve power by combining data from more than one study; we sought to determine whether platform-specific bias precludes direct integration of probe intensity signals for combined reanalysis. Results Using Affymetrix and Illumina data from the microarray quality control project, from our own clinical samples, and from additional publicly available datasets we evaluated several approaches to directly integrate intensity level expression data from the two platforms. After mapping probe sequences to Ensembl genes we demonstrate that, ComBat and cross platform normalisation (XPN, significantly outperform mean-centering and distance-weighted discrimination (DWD in terms of minimising inter-platform variance. In particular we observed that DWD, a popular method used in a number of previous studies, removed systematic bias at the expense of genuine biological variability, potentially reducing legitimate biological differences from integrated datasets. Conclusion Normalised and batch-corrected intensity-level data from Affymetrix and Illumina microarrays can be directly combined to generate biologically meaningful results with improved statistical power for robust, integrated reanalysis.

  18. Experimental and analytical study of loss-of-flow transients in EBR-II occurring at decay power levels

    International Nuclear Information System (INIS)

    A series of eight loss-of-flow (LOF) tests have been conducted in EBR-II to study the transition between forced and natural convective flows following a variety of loss-of-primary-pumping power conditions from decay heat levels. Comparisons of measurements and pretest/posttest predictions were made on a selected test. Good agreements between measurements and predictions was found prior to and just after the flow reaching its minimum, but the agreement is not as good after that point. The temperatures are consistent with the flow response and the assumed decay power. The measured results indicate that the flows of driver and the instrumented subassemblies are too much in the analytical model in the natural convective region. Although a parametric study on secondary flow, turbulent-laminar flow transition, heat transfer ability of the intermediate heat exchange at low flow and flow mixing in the primary tank has been performed to determine their effects on the flow, the cause of the discrepancy at very low flow level is still unknown

  19. Single DC-Sourced 9-level DC/AC Topology as Transformerless Power Interface for Renewable Sources

    Directory of Open Access Journals (Sweden)

    Juan R. Rodriguez-Rodríguez

    2015-02-01

    Full Text Available This paper introduces an advanced transformerless multilevel hybrid-conversion topology intended for the interconnection of renewable DC sources at small-scale. The most important contribution presented in this paper is the generation of two isolated DC sources from a single DC source without the use of any type of transformer. The DC sources feed a nine-level DC/AC hybrid cascade multilevel converter. This advanced topology is achieved by redesigning the conventional DC/DC Buck topology, attached to the multilevel converter, and embedding a suitable switching strategy along with a Field Programmable Gate Array (FPGA-based control. The advantages of the proposed structure, when compared to other proposals in the literature, are higher efficiency, reduced number of power switches, and high power density derived of transformerless characteristic. As a way to highlight differences and advantages of this converter over other options recently available in the literature, this paper carries out a quantitative evaluation comparing the number of voltage levels and the number of elements involved in the structure of DC/AC multilevel converters. The mathematical model and control strategy of the converter are explained and analyzed by means of simulations. Finally experimental results, obtained from a laboratory-scale prototype, show the performance of the system and demonstrate its relative advantages.

  20. A novel power control strategy of Modular Multi-level Converter in HVDC-AC hybrid transmission systems for passive networks

    DEFF Research Database (Denmark)

    Hu, Zhenda; Wu, Rui; Yang, Xiaodong;

    2014-01-01

    With the development of High Voltage DC Transmission (HVDC) technology, there will be more and more HVDC-AC hybrid transmission system in the world. A basic challenge in HVDC-AC hybrid transmission systems is to optimize the power sharing between DC and AC lines, which become more severe when...... supplying power for passive networks, as the surplus power can only flow back to power grids through the AC lines. To deal with this issue, it demands not only accurate system capability design but also flexible power control strategy of power converters in VSC-HVDC. This paper proposes a novel power...... control strategy of Modular Multi-level Converter in VSC-HVDC, which can optimize converter output power according to passive network loading variation. Proposal method is studied with a case study of a VSC-HVDC AC hybrid project by PSCAD/EMTDC simulations....

  1. Alpha spectral power and coherence in the patients with mild cognitive impairment during a three-level working memory task

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: The functional relationship between calculated alpha band spectral power and inter-/intra-hemispheric coherence during a three-level working memory task of patients with mild cognitive impairment (MCI) was investigated. Methods:Subjects included 35 MCI patients according to the DSM-Ⅳ criteria (mean age: 62.3, SD: 6.5) and 34 healthy controls (mean age:57.4, SD: 4.0) were selected from the community at large. All subjects performed a simple calculation and recall task with three levels of working memory load while electroencephalograph (EEG) signal was recorded. The spectral EEG power was computed over alphal (8.0~10.0 Hz) and alpha2 (10.5~13.0 Hz) frequency bands and was compared between rest stage and working memory processing stage by two-way ANOVA. Post hoc testing analyzed the differences between each two levels of working memory load during task processing. The inter-hemisphere EEG coherence of frontal (F3-F4), central (C3-C4), parietal (P3-P4), temporal (T5-T6) as well as occipital (O1-O2) was compared between MCI patients and normal controls. The EEG signals from F3-C3,F4-C4, C3-P3, C4-P4, P3-O1, P4-O2, T5-C3, T6-C4, T5-P3 and T6-P4 electrode pairs resulted from the intra-hemispheric action for alphal and alpha2 frequency bands. Result: There was significantly higher EEG power from MCI patients than from normal controls both at rest and during working memory processing. Significant differences existed between rest condition and three-level working memory tasks (P<0.001). The inter- and intra-hemispheric coherence during working memory tasks showed a "drop to rise" tendency compared to that at rest condition. There was significantly higher coherence in MCI patients than in the controls.When task difficulties increased, the cortical connectivity of intra-hemispheric diminished while the inter-hemispheric connectivity dominantly maintained the cognitive processing in MCI patients. Conclusion: The results of the present study indicate that the

  2. A low-power inverter-based CMOS level-crossing analog-to-digital converter for low-frequency biosignal sensing

    Science.gov (United States)

    Tanaka, Suiki; Niitsu, Kiichi; Nakazato, Kazuo

    2016-03-01

    Low-power analog-to-digital conversion is a key technique for power-limited biomedical applications such as power-limited continuous glucose monitoring. However, a conventional uniform-sampling analog-to-digital converter (ADC) is not suitable for nonuniform biosignals. A level-crossing ADC (LC-ADC) is a promising candidate for low-power biosignal processing because of its event-driven properties. The LC-ADC acquires data by level-crossing sampling. When an input signal crosses the threshold level, the LC-ADC samples the signal. The conventional LC-ADC employs a power-hungry comparator. In this paper, we present a low-power inverter-based LC-ADC. By adjusting the threshold level of the inverter, it can be used as a threshold-fixed window comparator. By using the inverter as an alternative to a comparator, power consumption can be markedly reduced. As a result, the total power consumption is successfully reduced by 90% of that of previous LC-ADC. The inverter-based LC-ADC was found to be very suitable for use in power-limited biomedical devices.

  3. Gear servicing in the wind power industry; Getriebeservice Windenergie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    JaKe (Jahnel-Kestermann) is a producer of gears for wind power systems. They offer: Damage analysis anddocumentation; supply of replacement parts; repair and modification of gears; world-wide gear servicing; new gears for own and external products; mobile measuring systems; technological improvements; production of components; toothing, grinding, meshing measurements; production of exchange gears; test performance up to 3 MW; short supply times. (orig.)

  4. Determination of {sup 93}Zr in medium and low level radioactive wastes from Brazilian nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Thiago C.; Oliveira, Arno H., E-mail: oliveiratco2010@gmail.com, E-mail: heeren@nuclear.ufmg.br [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Kastner, Geraldo F.; Monteiro, Roberto Pellacani G., E-mail: rpgm@cdtn.br, E-mail: gfk@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    The majority of long-lived radionuclides produced in the nuclear power plants can be regarded as difficult-to-measure radionuclides (RDM), hence chemical separation is necessary before the nuclear measurement of them. The zirconium isotope {sup 93}Zr is a long-lived pure β-particle-emitting radionuclide produced from {sup 235}U fission and from neutron activation of the stable isotope {sup 92}Zr and thus occurring as one of the radionuclides found in nuclear reactors. Due to its long half-life, {sup 93}Zr is one of the radionuclides of interest for the performance of assessment studies of waste storage or disposal. Two different methodologies based on extractive resins and LSC and ICP-MS techniques that enables the {sup 93}Zr determination in medium (ILW) and low level (LLW) radioactive wastes samples from Brazilian nuclear power plants has been developed in our laboratory. Analyzing real samples 65% and 75% chemical yields for {sup 93}Zr recovery were achieved for ICP-MS and LSC techniques, respectively. The detection limits were 0.045 μg.L{sup -1} for ICP-MS and 0.05 Bq.L{sup -1} for LSC techniques. (author)

  5. Unified System-Level Modeling of Intermittent Renewable Energy Sources and Energy Storage for Power System Operation

    DEFF Research Database (Denmark)

    Heussen, Kai; Koch, Stephan; Ulbig, Andreas;

    2011-01-01

    The system-level consideration of inter- mittent renewable energy sources and small-scale en- ergy storage in power systems remains a challenge as either type is incompatible with traditional operation concepts. Non-controllability and energy-constraints are still considered contingent cases...... impact and cost. By abstracting from technology-dependent and physical unit properties, the modeling framework presented and extended in this pa- per allows the modeling of a technologically diverse unit portfolio with a unied approach, whilst establishing the feasibility of energy-storage consideration...... in market-based operation. The design of operation strategies for up to 100 % renewable energy systems requires an explicit consideration of non-dispatchable generation and stor- age capacities, as well as the evaluation of operational performance in terms of energy eciency, reliability, environmental...

  6. Powerful Retailer`s Ordering Policy Under Two-Level Delay Permitted in Supply Chain Derived Without Derivatives

    Science.gov (United States)

    Kuang Yang, Wen; Huang, Hung-Fu; Tu, Yu-Cheng; Huang, Yung-Fu

    The main purpose of this study is to investigate the retailer`s inventory policy under two-level delay permitted to reflect the supply chain management situation. In this study, we assume that the retailer maintains a powerful position. So, it is assumed that the retailer can obtain the full trade credit offered by the supplier yet the retailer just offers the partial trade credit to his customers. Under these conditions, the retailer can obtain the most benefits. Then, an algebraic approach is provided to investigate the retailer=s inventory system as a cost minimization problem to determine the retailer=s optimal inventory policy under the supply chain management. One ease-to-use theorem is developed to efficiently determine the optimal inventory policy for the retailer. Finally, numerical examples are given to illustrate the theorem.

  7. High-power ICRF and ICRF plus neutral-beam heating on PLT

    International Nuclear Information System (INIS)

    PLT ICRF experiments with RF powers up to approx.=3 MW have demonstrated efficient plasma heating in both the minority fundamental and the second harmonic ion-cyclotron regimes. In the minority 3He regime, ion temperatures of approx.=3 keV have been produced along with approx.=1 kW of D-3He fusion power and substantial electron heating. In the second harmonic H regime, an equivalent averaged ion energy of approx.=4 keV has been achieved. Combined ICRF plus neutral-beam heating experiments with auxiliary powers totalling up to 4.5 MW have provided insight into auxiliary heating performance at stored plasma energy levels up to approx.=100 kJ. Values of #betta#sub(phi) in the range of 1.5-2% have been attained for Bsub(phi) approx.=17 kG. Energetic discharges with n-barsub(e) up to approx.6x1013 cm-3 at Bsub(phi) approx.=28 kG have also been investigated. Preliminary confinement studies suggest that energetic ion losses may contribute to a direct loss of the input RF power in the H minority heating regime but are insignificant in the 3He minority case. The energy confinement time for the H minority regime is reduced somewhat from the Ohmic value. (author)

  8. Actions taken on better earthquake resistance, level improvement and automation in the power distribution equipment; Haiden setsubi no taishin, kodoka, jidoka eno torikumi

    Energy Technology Data Exchange (ETDEWEB)

    Hara, N. [Agency of Natural Resources and Energy, Tokyo (Japan)

    1995-07-01

    This paper summarizes measures on earthquake resistance, level improvement and automation in power distribution equipment. Earthquake resistance in supports, transformers, wires, incoming lines, and underground wire ways has been handled in Japan according to the `technical criteria for electric facilities`. This is, however, compelled of reviewing with the great earthquake in 1995 as a turning point. Points of discussions include the review on earthquake resistance (considering earthquakes that occur directly below urban areas), improvement in urban power distribution network (network expansion and embedding the transmission lines), and emergency actions upon occurrence of disasters. The contents of the level improvement and automation may be summarized as follows: monitoring and control of distribution line devices including switch operation, automatic collection of power distribution management information intended of improving efficiency in the business operation, concentrated load control to achieve leveling of power loads, automatic meter-reading on power meters, and establishment of automatic and general power distribution system aiming at making common the use of devices, transmission paths, and signaling systems. The needs on information transmission utilizing power distribution equipment include stable power supply, diverse user services, and assurance of energy security. 2 figs.

  9. Power calibrations for TRIGA reactors

    International Nuclear Information System (INIS)

    The purpose of this paper is to establish a framework for the calorimetric power calibration of TRIGA reactors so that reliable results can be obtained with a precision better than ± 5%. Careful application of the same procedures has produced power calibration results that have been reproducible to ± 1.5%. The procedures are equally applicable to the Mark I, Mark II and Mark III reactors as well as to reactors having much larger reactor tanks and to TRIGA reactors capable of forced cooling up to 3 MW in some cases and 15 MW in another case. In the case of forced cooled TRIGA reactors, the calorimetric power calibration is applicable in the natural convection mode for these reactors using exactly the same procedures as are discussed below for the smaller TRIGA reactors (< 2 MW)

  10. A selective separation method for 93Zr in radiochemical analysis of low and intermediate level wastes from nuclear power plants

    International Nuclear Information System (INIS)

    The zirconium isotope 93Zr is a long-lived pure β-particle-emitting radionuclide produced from 235U fission and from neutron activation of the stable isotope 92Zr and thus occurring as one of the radionuclides found in nuclear reactors. Due to its long half life, 93Zr is one of the radionuclides of interest for the performance of assessment studies of waste storage or disposal. Measurement of 93Zr is difficult owing to its trace level concentration and its low activity in nuclear wastes and further because its certified standards are not frequently available. A radiochemical procedure based on liquid-liquid extraction with 1-(2-thenoyl)-3,3,3-trifluoroacetone in xylene, ion exchange with Dowex resin and selective extraction using TRU resin has to be carried out in order to separate zirconium from the matrix and to analyze it by liquid scintillation spectrometry technique (LSC). To set up the radiochemical separation procedure for 93Zr, a tracer solution of 95Zr was used in order to follow the behavior of zirconium during the process by γ-ray spectrometry through measurement of the 95Zr. Then, the protocol was applied to low level waste (LLW) and intermediate level waste (ILW) from nuclear power plants. The efficiency detection for 63Ni was used to determination of 93Zr activity in the matrices analyzed. The limit of detection of the 0.05 Bq l-1 was obtained for 63Ni standard solutions by using a sample:cocktail ratio of 3:17 mL for OptiPhase HiSafe 3 cocktail. (author)

  11. Improved sampling and analytical techniques for characterization of very-low-level radwaste materials from commercial nuclear power stations

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, D.E. [Pacific Northwest Labs., Richland, WA (United States); Robinson, P.J. [Electric Power Research Inst., Palo Alto, CA (United States)

    1989-11-01

    This paper summarizes the unique sampling methods that were utilized in a recently completed project sponsored by the Electric Power Research Institute (EPRI) to perform accurate and precise radiological characterizations of several very-low-level radwaste materials from commercial nuclear power stations. The waste types characterized during this project included dry active waste (DAW), oil, secondary-side ion exchange resin, and soil. Special precautions were taken to insure representative sampling of the DAW. This involved the initial direct, quantitative gamma spectrometric analyses of bulk quantities (208-liter drums) of DAW utilizing a specially constructed barrel scanner employing a collimated intrinsic germanium detector assembly. Subsamples of the DAW for destructive radiochemical analyses of the difficult-to-measure 10CF61 radionuclides were then selected which had the same isotopic composition (to within {+-}25%) as that measured for the entire drum of DAW. The techniques for accomplishing this sampling are described. Oil samples were collected from the top, middle and bottom sections of 208-liter drums for radiochemical analyses. These samples were composited to represent the entire drum of oil. The accuracy of this type of sampling was evaluated by comparisons with direct, quantitative assays of a number of the drums using the barrel scanning gamma-ray spectrometer. The accuracy of sampling drums of spent secondary-side ion exchange resin was evaluated by comparing the radionuclide contents of grab samples taken from the tops of the drums with direct assays performed with the barrel scanner. The results of these sampling evaluations indicated that the sampling methods used were generally adequate for providing a reasonably representative subsample from bulk quantities of DAW, oil, and resin. The study also identified a number of potential pitfalls, in sampling of these materials.

  12. Design for Reliability of Power Electronic Systems

    DEFF Research Database (Denmark)

    Wang, Huai; Ma, Ke; Blaabjerg, Frede

    2012-01-01

    Advances in power electronics enable efficient and flexible processing of electric power in the application of renewable energy sources, electric vehicles, adjustable-speed drives, etc. More and more efforts are devoted to better power electronic systems in terms of reliability to ensure high...... availability, long lifetime, sufficient robustness, low maintenance cost and low cost of energy. However, the reliability predictions are still dominantly according to outdated models and terms, such as MIL-HDBK-217F handbook models, Mean-Time-To-Failure (MTTF), and Mean-Time-Between-Failures (MTBF...... on a 2.3 MW wind power converter is discussed with emphasis on the reliability critical components IGBTs. Different aspects of improving the reliability of the power converter are mapped. Finally, the challenges and opportunities to achieve more reliable power electronic systems are addressed....

  13. Latent heat augmentation of thermocline energy storage for concentrating solar power – A system-level assessment

    International Nuclear Information System (INIS)

    Highlights: • We develop a new PCM-filled thermocline tank model to assess storage behavior. • A parametric study of PCM melting temperature and heat of fusion is performed. • Tanks filled with a single PCM do not provide benefit over baseline rock filler. • A cascaded PCM structure boosts energy density with suitable melt temperatures. - Abstract: Molten-salt thermocline tanks are a low-cost energy storage option for concentrating solar power plants. Despite the potential economic advantage, the capacity of thermocline tanks to store sufficient amounts of high-temperature heat is limited by the low energy density of the constituent sensible-heat storage media. A promising design modification replaces conventional rock filler inside the tank with an encapsulated phase-change material (PCM), contributing a latent heat storage mechanism to increase the overall energy density. The current study presents a new finite-volume approach to simulate mass and energy transport inside a latent heat thermocline tank at low computational cost. This storage model is then integrated into a system-level model of a molten-salt power tower plant to inform tank operation with respect to realistic solar collection and power production. With this system model, PCMs with different melting temperatures and heats of fusion are evaluated for their viability in latent heat storage for solar plants. Thermocline tanks filled with a single PCM do not yield a substantial increase in annual storage or plant output over a conventional rock-filled tank of equal size. As the melting temperature and heat of fusion are increased, the ability of the PCM to support steam generation improves but the corresponding ability of the thermocline tank to utilize this available latent heat decreases. This trend results from an inherent deconstruction of the heat-exchange region inside the tank between sensible and latent heat transfer, preventing effective use of the added phase change for daily plant

  14. Procedures for conducting probabilistic safety assessments of nuclear power plants (level 2). Accident progression, containment analysis and estimation of accident source terms

    International Nuclear Information System (INIS)

    The present publication on Level 2 PSA is based on a compilation and review of practices in various Member States. It complements Safety Series No. 50-P-4, issued in 1992, on Procedures for Conducting Probabilistic Safety Assessments of Nuclear Power Plants (Level 1). Refs, figs and tabs

  15. Modernization of the feedwater heaters control level of the Almaraz I Nuclear Power Plant by OVATION system

    International Nuclear Information System (INIS)

    As a result of the process of technological renovation of the heaters system and the power increase project, Almaraz Nuclear Power Plant has made several design changes in the feedwater heaters system. Within these changes, the old heaters control loops are replaced because the new power will increase the heaters drainage caudal. This modernization is carried out using the OVATION control system.

  16. THE RELATIONSHIP BETWEEN AEROBIC POWER AND REPEATED SPRINT ABILITY IN YOUNG SOCCER PLAYERS WITH DIFFERENT LEVELS OF VO2 MAX

    Directory of Open Access Journals (Sweden)

    Rostam Alizadeh

    2010-06-01

    Full Text Available In some team sports such as soccer which is interval, athletes need to prepare themselves immediatelyfor the next activity. Therefore it is very important to have enough information on characteristics of recovery phase and quick recovery to the first situation and to have the minimum speed reduction. The purpose of this study was to determine the relationship between aerobic power and repeated sprint ability (RSA or decrementindex in young soccer players in three different levels of Vo2max. Methods: For this reason 41 volunteers were divided in to three groups with different levels of Vo2max ml.kg-1.min-1 low 37.22 ± 2.3 (n= 18, age 17.1 ± 0.9 year, height 170.6 ± 0.76 cm, weight 67.1 ± 5.05 kg medium 46.46± 1.97 ml.kg-1.min-1 (n= 13, age 17.6± 0.76year, height 173.8 ± 4.84 cm, weight 65.9 ± 4.92 kg and high 55.63 ± 1.52 ml.kg-1.min-1 (n=10, age 17.4 ±0.69 year, height 177 ± 3.23 cm, weight 71.4 ± 3.94 kg. To determine Vo2max a graded exercise test until volitional exhaustion on treadmill was used, and also RAST was used to measure RSA. The lactate accumulation was measured before and after RSA protocol. Pearson's correlation was used to determine the correlation between the aerobic power and RSA. The results indicated that there are significant relationship between Vo2max anddecremental index in low Vo2max group (r= 0.86, p= 0.001, no significant relationship medium Vo2max group (r= 0.14, p= 0.63 and negative significant relationship in high Vo2max group (r= - 0.64, p= 0.04. There are no significant relationship between Lactate accumulation and decremental index in medium (r= 0.005, p= 0.98 and high Vo2max groups (r=0.27, p= 0.45. Discussion: It is possible that the recovery of inter muscular resources relates to aerobic ability, but there are other factors effective in RSA rather than Vo2max and Lactate accumulation. The current study showed a normal curved relationship between Vo2max and RSA.

  17. Minimizing the Levelized Cost of Energy in Single-Phase Photovoltaic Systems with an Absolute Active Power Control

    DEFF Research Database (Denmark)

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya;

    2017-01-01

    Countries with considerable PhotoVoltaic (PV) installations are facing a challenge of overloading their power grid during peak-power production hours if the power infrastructure remains the same. To address this, regulations have been imposed on PV systems, where more active power control should...... Of Energy (LCOE), the power limit is optimized for the AAPC strategy in this paper. The optimization method is demonstrated on a 3-kW single-phase PV system considering a real-field mission profile (i.e., solar irradiance and ambient temperature). The optimization results have revealed that superior...... performance in terms of LCOE and energy production can be obtained by enabling the AAPC strategy, compared to the conventional PV inverter operating only in the maximum power point tracking mode. In the presented case study, the minimum of the LCOE is achieved for the PV system when the power limit...

  18. Power and area efficient 4-bit column-level ADC in a CMOS pixel sensor for the ILD vertex detector

    International Nuclear Information System (INIS)

    A 48 × 64 pixels prototype CMOS pixel sensor (CPS) integrated with 4-bit column-level, self triggered ADCs for the outer layers of the ILD vertex detector (VTX) was developed and fabricated in a 0.35 μm CMOS process with a pixel pitch of 35 μm. The pixel concept combines in-pixel amplification with a correlated double sampling (CDS) operation. The ADCs accommodating the pixel read out in a rolling shutter mode complete the conversion by performing a multi-bit/step approximation. The design was optimised for power saving at sampling frequency. The prototype sensor is currently at the stage of being started testing and evaluation. So what is described is based on post simulation results rather than test data. This 4-bit ADC dissipates, at a 3-V supply and 6.25-MS/s sampling rate, 486 μW in its inactive mode, which is by far the most frequent. This value rises to 714 μW in case of the active mode. Its footprint amounts to 35 × 545 μm2.

  19. Laser inertial fusion dry-wall materials response to pulsed ions at power-plant level fluences

    Science.gov (United States)

    Renk, T. J.; Tanaka, T. J.; Olson, C. L.; Peterson, R. R.; Knowles, T. R.

    2004-08-01

    Pulses of MeV-level ions with fluences of up to 20 J/cm 2 can be expected to impinge on the first-wall of future laser-driven Inertial Fusion Energy (IFE) power plants. To simulate the effect of these ions, we have exposed candidate dry-wall materials to ion pulses from RHEPP-1, located at Sandia National Laboratories. Various forms of tungsten and tungsten alloy were exposed to up to 1000 pulses, with some samples heated to 600 °C. Thresholds for roughening and material removal, and evolution of surface morphology were measured and compared with code predictions for materials response. Tungsten is observed to undergo surface roughening and subsurface crack formation that evolves over hundreds of pulses, and which can occur both below and above the melt threshold. Heating and Re-alloying mitigate, but do not eliminate, these apparently thermomechanically-caused effects. Use of a 3-D geometry, and/or use of the tungsten in thin-film form may offer improved survivability compared to bulk tungsten.

  20. Measures of nonclassicality for a two-level atom interacting with power-law potential field under decoherence effect

    Science.gov (United States)

    Abdel-Khalek, S.; Berrada, K.; Alkhateeb, Sadah A.

    2016-09-01

    In this paper, we propose a useful quantum system to perform different tasks of quantum information and computational technologies. We explore the required optimal conditions for this system that are feasible with real experimental realization. We present an active way to control the variation of some measures of nonclassicality considering the time-dependent coupling and photon transition effects under a model that closely describes a realistic experimental scenario. We investigate qualitatively the quantum measures for a two-level atom system interacting with a quantum field initially defined in a coherent state in the framework of power-law potentials (PLPCSs). We study the nonlocal correlation in the whole system state using the negativity as a measure of entanglement in terms of the exponent parameter, number of photon transition, and phase damping effect. The influences of the different physical parameters on the statistical properties and purity of the field are also demonstrated during the time evolution. The results indicate that the preservation and enhancement of entanglement greatly benefit from the combination of the choice of the physical parameters. Finally, we explore an interesting relationship between the different quantum measures of non-classicality during the time evolution in the absence and presence of time-dependent coupling effect.

  1. Power and area efficient 4-bit column-level ADC in a CMOS pixel sensor for the ILD vertex detector

    Science.gov (United States)

    Zhang, L.; Morel, F.; Hu-Guo, Ch; Hu, Y.

    2013-01-01

    A 48 × 64 pixels prototype CMOS pixel sensor (CPS) integrated with 4-bit column-level, self triggered ADCs for the outer layers of the ILD vertex detector (VTX) was developed and fabricated in a 0.35 μm CMOS process with a pixel pitch of 35 μm. The pixel concept combines in-pixel amplification with a correlated double sampling (CDS) operation. The ADCs accommodating the pixel read out in a rolling shutter mode complete the conversion by performing a multi-bit/step approximation. The design was optimised for power saving at sampling frequency. The prototype sensor is currently at the stage of being started testing and evaluation. So what is described is based on post simulation results rather than test data. This 4-bit ADC dissipates, at a 3-V supply and 6.25-MS/s sampling rate, 486 μW in its inactive mode, which is by far the most frequent. This value rises to 714 μW in case of the active mode. Its footprint amounts to 35 × 545 μm2.

  2. Predictive Current Control of a 7-level AC-DC back-to-back Converter for Universal and Flexible Power Management System

    DEFF Research Database (Denmark)

    Bifaretti, Steffano; Zanchetta, Pericle; Iov, Florin;

    2008-01-01

    The paper proposes a novel power conversion system for Universal and Flexible Power Management (UNIFLEX-PM) in Future Electricity Network. Its structure is based on a back-to-back three-phase AC-DC 7-level converter; each AC side is connected to a different PCC, representing the main grid and/or ...... numerous network conditions such as voltage unbalance, frequency excursions and harmonic distortion....

  3. Power Capability Investigation Based on Electrothermal Models of Press-pack IGBT Three-Level NPC and ANPC VSCs for Multimegawatt Wind Turbines

    DEFF Research Database (Denmark)

    Senturk, Osman Selcuk; Helle, Lars; Munk-Nielsen, Stig;

    2012-01-01

    are addressed in this study for the three-level neutral-point-clamped voltage source converter (3L-NPC-VSC) and 3L Active NPC VSC (3L-ANPC-VSC) with press-pack insulated gate bipolar transistors employed as a grid-side converter. In order to investigate these VSCs' power capabilities under various operating...... conditions with respect to these limiting factors, a power capability generation algorithm based on the converter electrothermal model is developed. Built considering the VSCs' operation principles and physical structure, the model is validated by a 2 MV·A single-phase 3L-ANPC-VSC test setup. The power...

  4. Themis - A solar power station

    Science.gov (United States)

    Hillairet, J.

    The organization, goals, equipment, costs, and performance of the French Themis (Thermo-helio-electric-MW) project are outlined. The program was begun for both the domestic energy market and for export. The installation comprises a molten eutectic salt loop which receives heat from radiators situated in a central tower. The salt transfers the heat to water for steam generation of electricity. A storage tank holds enough molten salt to supply one day's reserve of power, 40 MWh. A field of heliostats directs the suns rays for an estimated 2400 hr/yr onto the central receiver aperture, while 11 additional parabolic concentrators provide sufficient heat to keep the salt reservoir at temperatures exceeding 200 C. In a test run of several months during the spring of 1982 the heliostats directed the sun's rays with an average efficiency of 75 percent, yielding 2.3 MW of power at a system efficiency of 20.5 percent in completely automatic operation.

  5. Near-Field Acoustic Power Level Analysis of F31/A31 Open Rotor Model at Simulated Cruise Conditions, Technical Report II

    Science.gov (United States)

    Sree, Dave

    2015-01-01

    Near-field acoustic power level analysis of F31A31 open rotor model has been performed to determine its noise characteristics at simulated cruise flight conditions. The non-proprietary parts of the test data obtained from experiments in the 8x6 supersonic wind tunnel were provided by NASA-Glenn Research Center. The tone and broadband components of total noise have been separated from raw test data by using a new data analysis tool. Results in terms of sound pressure levels, acoustic power levels, and their variations with rotor speed, freestream Mach number, and input shaft power, with different blade-pitch setting angles at simulated cruise flight conditions, are presented and discussed. Empirical equations relating models acoustic power level and input shaft power have been developed. The near-field acoustic efficiency of the model at simulated cruise conditions is also determined. It is hoped that the results presented in this work will serve as a database for comparison and improvement of other open rotor blade designs and also for validating open rotor noise prediction codes.

  6. Metal impurity transport control in JET H-mode plasmas with central ion cyclotron radiofrequency power injection

    DEFF Research Database (Denmark)

    Valisa, M.; Carraro, L.; Predebon, I.;

    2011-01-01

    of injected power. Above a threshold of ICRH power of about 3 MW in the specific case the radial flow of Ni and Mo changes from inwards to outwards and the impurity profiles, extrapolated to stationary conditions, become hollow. At mid-radius the impurity profiles become flat or only slightly hollow...... order of magnitude. Gyrokinetic simulations of the radial impurity fluxes induced by electrostatic turbulence do not foresee a flow reversal in the analysed discharges....

  7. (14)C levels in the vicinity of the Fukushima Dai-ichi Nuclear Power Plant prior to the 2011 accident.

    Science.gov (United States)

    Xu, Sheng; Cook, Gordon T; Cresswell, Alan J; Dunbar, Elaine; Freeman, Stewart P H T; Hastie, Helen; Hou, Xiaolin; Jacobsson, Piotr; Naysmith, Philip; Sanderson, David C W; Tripney, Brian G; Yamaguchi, Katsuhiko

    2016-06-01

    A 50-year-old Japanese cedar (Cryptomeria japonica) from Okuma, ∼1 km southwest of the Fukushima Dai-ichi Nuclear Power Plant, was cored and each annual ring was analysed for (14)C. The (14)C specific activity values varied from 330.4 Bq kg(-1) C in the tree ring formed in 1971 to 231.2 Bq kg(-1) C in the 2014 ring. During the periods 1971-1976 and 2011-2014, the (14)C specific activities are indistinguishable from the ambient background values. However, compared with the ambient atmospheric levels, the (14)C specific activities between 1977 and 2010 are significantly elevated, clearly indicating (14)C discharges from the reactors during their normal operations. In addition, the specific activities are positively correlated with the annual electricity generation values. The excess (14)C specific activities were wind direction is east-southeast/southeast with a frequency of ∼30%, in comparison to ∼20% frequency for the direction of the site under study (north-northeast/northeast). This would tend to indicate a similar magnitude of additional effective dose and consequently no significant radiological impact of atmospheric (14)C discharges from the FDNPP during the entire period of normal operations. Additionally, no (14)C pulse in activity can be observed in the year 2011 ring. This might be caused by a limited (14)C release from the damaged reactors during the accident or that the prevailing wind during the short period of release (11th-25th March 2011) was not in the direction of Okuma.

  8. The democratisation of nuclear power policy in Japan; Focusing on strategies for geological disposal of high-level radioactive waste

    International Nuclear Information System (INIS)

    As public opposition is seen as the main factor prohibiting siting of high level waste repositories, we address the underlying causes of public opposition in Japan and the current measures being taken by the government and industry to address these issues. Furthermore, this lack of siting in turn raises questions concerning the future of nuclear power as an energy source and accompanying fuel cycle issues. This paper describes the conduct and results of the hearing sessions and their influence on the final recommendations. We also describe the progress of the recent efforts. Furthermore, the Atomic Energy Commission of Japan (AECJ) has founded another committee to integrate the public's views in forming the new body for the implementation of the disposal action plan. The main institutions or parties involved in nuclear energy policy in Japan include the AECJ, which promotes the development of nuclear energy; the Nuclear Safety Commission (NSC), which is responsible for the safety; Science and Technology Agency (STA), which provides support work and analysis for the NSC and AECJ; Ministry for International Trade and Industry (MITI) which is responsible for overall energy policy; the utilities and industry, local governments, anti-nuclear groups and the media. After the accident at Monju, three governors of nuclear plant concentrated prefectures wrote a letter of protest to the national government stating that they would not support the government energy strategy without public consensus building. They also called for greater efforts by the national government's energy policy to ensure safety. In the spring of 1996, the government, through the oversight of the AECJ, began a series of round table discussions. Prior to these meetings, policy making had ended with the input of the experts; the government is now making a serious attempt to integrate the public in the policy process. The attempt has been particularly evident in the policy-making process regarding the

  9. Power Analysis to Detect the Effects of a Continuous Moderator in 2-Level Simple Cluster Random Assignment Experiments

    Science.gov (United States)

    Dong, Nianbo

    2014-01-01

    For intervention studies involving binary treatment variables, procedures for power analysis have been worked out and computerized estimation tools are generally available. The purpose of this study is to: (1) develop the statistical formulations for calculating statistical power, minimum detectable effect size (MDES) and its confidence interval,…

  10. Wind power in power systems

    CERN Document Server

    Ackermann, Thomas

    2012-01-01

    The second edition of the highly acclaimed Wind Power in Power Systems has been thoroughly revised and expanded to reflect the latest challenges associated with increasing wind power penetration levels. Since its first release, practical experiences with high wind power penetration levels have significantly increased. This book presents an overview of the lessons learned in integrating wind power into power systems and provides an outlook of the relevant issues and solutions to allow even higher wind power penetration levels. This includes the development of standard wind turbine sim

  11. Effect of variable power levels on the yield of total aerosol mass and formation of aldehydes in e-cigarette aerosols.

    Science.gov (United States)

    Gillman, I G; Kistler, K A; Stewart, E W; Paolantonio, A R

    2016-03-01

    The study objective was to determine the effect of variable power applied to the atomizer of refillable tank based e-cigarette (EC) devices. Five different devices were evaluated, each at four power levels. Aerosol yield results are reported for each set of 25 EC puffs, as mass/puff, and normalized for the power applied to the coil, in mass/watt. The range of aerosol produced on a per puff basis ranged from 1.5 to 28 mg, and, normalized for power applied to the coil, ranged from 0.27 to 1.1 mg/watt. Aerosol samples were also analyzed for the production of formaldehyde, acetaldehyde, and acrolein, as DNPH derivatives, at each power level. When reported on mass basis, three of the devices showed an increase in total aldehyde yield with increasing power applied to the coil, while two of the devices showed the opposite trend. The mass of formaldehyde, acetaldehyde, and acrolein produced per gram of total aerosol produced ranged from 0.01 to 7.3 mg/g, 0.006 to 5.8 mg/g, and aerosols from specific devices, and were compared to estimated exposure from consumption of cigarettes, to occupational and workplace limits, and to previously reported results from other researchers. PMID:26743740

  12. Safety Management of County-level Power Supply Enterprises%县级供电企业安全管理探析

    Institute of Scientific and Technical Information of China (English)

    张曙光

    2013-01-01

      随着农电体制改革的深化,农电事业有了长足发展,农电管理中一些新的矛盾也随之显现出来。安全生产是电力企业永恒的主题。大家知道,作为县级供电企业,抓好安全生产管理工作的重要作用和意义日益凸显,要确保县级供电企业安全生产,必须建设一支“一强三优”县级供电企业队伍,强化安全生产管理,实现县级供电企业管理与网、省公司管理全面融合。安全生产管理抓得好。无论对确保社会稳定和人民生命财产不受损失,还是对县级供电企业本身经济效益和社会效益都具有十分重要作用。%With deepening of reform of rural power system, the rural power enterprises have made remarkable development, some new contradictions in rural power management also unfold. Production safety is the eternal theme in the electric power enterprise. As we all know, as a county-level power supply enterprise, pays special attention to the safety in production important function and meaning of management, to ensure that the county level power supply enterprise safety in production, to build a "one strong three-excellent" county-level power supply enterprise team, strengthening the management of production safety and implementation at the county level power supply enterprises, provincial company management comprehensive integration management and network. Safety production management is a good catch. No matter to ensure social stability and people's life and property from losses, or economic benefit and social benefit of county-level power supply enterprise itself has a very important role.

  13. Loss and thermal redistributed modulation methods for three-level neutral-point-clamped wind power inverter undergoing Low Voltage Ride Through

    DEFF Research Database (Denmark)

    Ma, Ke; Blaabjerg, Frede

    2012-01-01

    investigates the loss and thermal performances of a 10 MW 3L-NPC wind power inverter undergoing Low Voltage Ride Through (LVRT) operation. A series of new space vector modulation methods are then proposed to relocate the thermal loading among the power switching devices. It is concluded that, with the proposed......The three-level neutral-point-clamped (3L-NPC) converter is a promising multilevel topology in the application of mega-watts wind power generation system. However, the growing requirements by grid codes may impose high stress and even give reliability problem to this converter topology. This paper...... modulation methods, the thermal distribution in the 3L-NPC wind power inverter undergoing LVRT becomes more equal, and the junction temperature of the most stressed devices can be also relieved. Also the control ability of DC-bus neutral point potential, which is one of the crucial considerations for the 3L...

  14. On the County Level Power Supply Enterprise Management%浅谈县级供电企业经营管理

    Institute of Scientific and Technical Information of China (English)

    何伟松

    2014-01-01

    The county power enterprises as low-level power supply enterprise, its supply and quality of service is closely related to people’s daily lives. Therefore, county power enterprises to improve their business management and economic benefits of people's living standards have an important role in the enterprise. To expand the county power enterprise management is discussed in detail.%县级供电企业作为较低一级的供电企业,其供电服务质量与人们的日常生活密切相关。因此,县级供电企业做好其经营管理工作对提高人们的生活水平和企业的经济效益具有重要的作用。就县级供电企业经营管理展开详细的论述。

  15. Clearance level (de minimis) : examples of difficulties met in the nuclear power plants of EDF about the very low level active waste management

    International Nuclear Information System (INIS)

    The absence of a clear reglementation concerning very low radioactive waste management has led EDF to harmonise its internal practices. However plant operators are still confronted with many difficulties for: very low radioactive waste which have really been contaminated; very low radioactive waste whose radioactivity is not due to on a site nuclear practices (natural radioactivity of off-site artificial radioactivity); waste which is suspected to be contaminated simply because it has transited through a nuclear power plant even outside of all controlled areas. (author)

  16. An radiotoxicity evaluation of high level wastes for a scenery of Brazilian Nuclear Power Plants in accordance with the Energy Expansion Brazilian Plan 2030

    International Nuclear Information System (INIS)

    This paper is a part of the author scientific initiation, and makes an evaluation of the radiotoxicity which would be produced by the Brazilian nuclear power plants in a scenery of 7 power plants operating in 2030, in according to the official expansion plans which point out the additional introduction of 4000 MW(e), or 4 ne power plant additionally to the Angra I, II and III. Considering that all reactors would be a PWR reactors. The calculated parameter was the relative toxicity of the low and intermediate level nuclear wastes (LLPP - long lived fission products and HLW - high level waste related to the radiotoxicity of natural uranium versus time. All the calculation used the ORIGEN-S code. (author)

  17. The discriminative power of the Interval Shuttle Run Test and the Maximal Multistage Shuttle Run Test for playing level of soccer

    NARCIS (Netherlands)

    Lemmink, K.A.P.M.; Verheijen, R.; Visscher, C.

    2004-01-01

    AIM: The purpose of this study was to examine the discriminative power of the recently developed Interval Shuttle Run Test (ISRT) and the widely used Maximal Multistage 20 m Shuttle Run Test (MMSRT) for soccer players at different levels of competition. The main difference between the tests is that

  18. High-power and steady-state operation of ICRF heating in the large helical device

    Energy Technology Data Exchange (ETDEWEB)

    Mutoh, T., E-mail: mutoh@nifs.ac.jp; Seki, T.; Saito, K.; Kasahara, H.; Seki, R.; Kamio, S.; Kumazawa, R.; Kubo, S.; Shimozuma, T.; Yoshimura, Y.; Igami, H.; Takahashi, H.; Ii, T.; Makino, R.; Nagaoka, K.; Nomura, G. [National Institute for Fusion Science, 322-6, Oroshi-cho, Toki, Gifu, 509-5292 (Japan); Shinya, T. [The University of Tokyo, Kashiwa 2777-8561 (Japan)

    2015-12-10

    Recent progress in an ion cyclotron range of frequencies (ICRF) heating system and experiment results in a Large Helical Device (LHD) are reported. Three kinds of ICRF antenna pairs were installed in the LHD, and the operation power regimes were extended up to 4.5 MW; also, the steady-state operation was extended for more than 45 min in LHD at a MW power level. We studied ICRF heating physics in heliotron configuration using a Hand Shake type (HAS) antenna, Field Aligned Impedance Transforming (FAIT) antenna, and Poloidal Array (PA) antenna, and established the optimum minority-ion heating scenario in an LHD. The FAIT antenna having a novel impedance transformer inside the vacuum chamber could reduce the VSWR and successfully injected a higher power to plasma. We tested the PA antennas completely removing the Faraday-shield pipes to avoid breakdown and to increase the plasma coupling. The heating performance was almost the same as other antennas; however, the heating efficiency was degraded when the gap between the antenna and plasma surface was large. Using these three kinds of antennas, ICRF heating could contribute to raising the plasma beta with the second- and third-harmonic cyclotron heating mode, and also to raising the ion temperature as discharge cleaning tools. In 2014, steady-state operation plasma with a line-averaged electron density of 1.2 × 10{sup 19} m{sup −3}, ion and electron temperature of 2 keV, and plasma sustainment time of 48 min was achieved with ICH and ECH heating power of 1.2 MW for majority helium with minority hydrogen. In 2015, the higher-power steady-state operation with a heating power of up to 3 MW was tested with higher density of 3 × 10{sup 19} m{sup −3}.

  19. Replacement of the level control of draining tanks MSRS and powered water heaters with the OVATION system in Asco NPP

    International Nuclear Information System (INIS)

    The current MSR drains and heaters tanks level control is local control individual, pneumatic and without action from Control room. The system has level switches for the generation of alarms, isolations and shots of bombs. Single control room operators have level alarms, final race of valves of control and indication of temperature and pressure of some tanks.

  20. Estimation of an Effective Young’s Modulus of Elasticity in the Locality of the Gabčíkovo Hydrology Power Plant by Geometric Leveling

    OpenAIRE

    Mojzeš Marcel; Kollár Pavol; Mikolaj Michal

    2015-01-01

    The Gabčíkovo hydroelectric power plant is located in a complicated geological environment (gravel sub-soil and a high groundwater level). Excavation work started after the withdrawal of water in the autumn of 1984 and lasted until the autumn of 1986. A basic geodetic control network with a special monument was founded before the excavation work began. This network served for the setting-out of the hydroelectric power plant as well as for the control of the excavation work. The repeated geode...

  1. A review of water use in the U.S. electric power sector: insights from systems-level perspectives

    Science.gov (United States)

    Thermoelectric power production comprised 41% of total freshwater withdrawals in the U.S., surpassing even agriculture. This review highlights scenarios of the electric sector’s future demands for water, including scenarios that limit both CO2 and water availability. A number o...

  2. Converter Structure-Based Power Loss and Static Thermal Modeling of The Press-Pack IGBT Three-Level ANPC VSC Applied to Multi-MW Wind Turbines

    DEFF Research Database (Denmark)

    Senturk, Osman Selcuk; Helle, Lars; Munk-Nielsen, Stig;

    2011-01-01

    performance, the converter structure-based power loss and thermal models are developed in this study for the medium-voltage (MV) three-level active neutral-point-clamped voltage source converter (3L-ANPC-VSC) utilizing 4500 V-1800 A press-pack insulated-gate bipolar transistor-diode pairs and interfacing a 6...... MW wind turbine to a MV grid. The switching power loss models are built using the experimental switching power loss data acquired via the double-pulse tests conducted on a full-scale 3L-ANPC-VSC prototype. The converter static thermal model is developed based on the double-sided water-cooled press-pack...

  3. Levels of {sup 137}Cs and {sup 40}K in marine superficial sediments near the Angra Nuclear Power Plant (Angra dos Reis, SE Brazil)

    Energy Technology Data Exchange (ETDEWEB)

    Lima Ferreira, Paulo Alves de; Farina Amorim, Lais; Marone Tura, Pedro; Medeiros Zacheo, Valter Andre; Lopes Figueira, Rubens Cesar [Universidade de Sao Paulo (IO-USP), SP (Brazil). Inst. Oceanografico

    2015-07-01

    This study evaluated the spatial distribution of two environmentally relevant radionuclides, {sup 137}Cs and {sup 40}K, in marine superficial sediments around the Angra Nuclear Power Plant, the only Brazilian nuclear power plant complex, thus establishing a baseline for bottom sediments, given the international importance of environmental monitoring around nuclear facilities. It was observed that these radionuclides are mostly present in the muddy sediments as a result of their stronger association with its fine-grained fraction, and that their lowest levels are located around the liquid effluent discharge of the plant, as a consequence of the prevented deposition of fine sediments due to the strong discharge water flux. The comparison of the {sup 137}Cs activities in the region with other locations in the world showed that the presence of this artificial nuclide is due to the atmospheric fallout from past nuclear tests made during the Cold War, not to the nuclear power plant activities.

  4. Use of cost benefit analysis methodology in the meaning of motorization level from small and medium hydroelectric power plants

    International Nuclear Information System (INIS)

    The technical and economic justifications that bringing the waterfall division reformulation between Lucas Nogueira Garcez Plant and Capivara Plant in Paranapanema River (Brazil) are described, including a comparative economic of Canoas (Alta), Canoas I and Canoas II passages, motorization study and energetic benefits. The reasons of the Bulbo turbines choice and dimensioning definition of the installed power by the new reference economic parameters are also presented. (C.G.C.). 5 refs, 11 tabs

  5. 'The one with the purse makes policy': Power, problem definition, framing and maternal health policies and programmes evolution in national level institutionalised policy making processes in Ghana.

    Science.gov (United States)

    Koduah, Augustina; Agyepong, Irene Akua; van Dijk, Han

    2016-10-01

    This paper seeks to advance our understanding of health policy agenda setting and formulation processes in a lower middle income country, Ghana, by exploring how and why maternal health policies and programmes appeared and evolved on the health sector programme of work agenda between 2002 and 2012. We theorized that the appearance of a policy or programme on the agenda and its fate within the programme of work is predominately influenced by how national level decision makers use their sources of power to define maternal health problems and frame their policy narratives. National level decision makers used their power sources as negotiation tools to frame maternal health issues and design maternal health policies and programmes within the framework of the national health sector programme of work. The power sources identified included legal and structural authority; access to authority by way of political influence; control over and access to resources (mainly financial); access to evidence in the form of health sector performance reviews and demographic health surveys; and knowledge of national plans such as Ghana Poverty Reduction Strategy. Understanding of power sources and their use as negotiation tools in policy development should not be ignored in the pursuit of transformative change and sustained improvement in health systems in low- and middle income countries (LMIC).

  6. 'The one with the purse makes policy': Power, problem definition, framing and maternal health policies and programmes evolution in national level institutionalised policy making processes in Ghana.

    Science.gov (United States)

    Koduah, Augustina; Agyepong, Irene Akua; van Dijk, Han

    2016-10-01

    This paper seeks to advance our understanding of health policy agenda setting and formulation processes in a lower middle income country, Ghana, by exploring how and why maternal health policies and programmes appeared and evolved on the health sector programme of work agenda between 2002 and 2012. We theorized that the appearance of a policy or programme on the agenda and its fate within the programme of work is predominately influenced by how national level decision makers use their sources of power to define maternal health problems and frame their policy narratives. National level decision makers used their power sources as negotiation tools to frame maternal health issues and design maternal health policies and programmes within the framework of the national health sector programme of work. The power sources identified included legal and structural authority; access to authority by way of political influence; control over and access to resources (mainly financial); access to evidence in the form of health sector performance reviews and demographic health surveys; and knowledge of national plans such as Ghana Poverty Reduction Strategy. Understanding of power sources and their use as negotiation tools in policy development should not be ignored in the pursuit of transformative change and sustained improvement in health systems in low- and middle income countries (LMIC). PMID:27614028

  7. Evaluation of training programs and entry-level qualifications for nuclear-power-plant control-room personnel based on the systems approach to training

    Energy Technology Data Exchange (ETDEWEB)

    Haas, P M; Selby, D L; Hanley, M J; Mercer, R T

    1983-09-01

    This report summarizes results of research sponsored by the US Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research to initiate the use of the Systems Approach to Training in the evaluation of training programs and entry level qualifications for nuclear power plant (NPP) personnel. Variables (performance shaping factors) of potential importance to personnel selection and training are identified, and research to more rigorously define an operationally useful taxonomy of those variables is recommended. A high-level model of the Systems Approach to Training for use in the nuclear industry, which could serve as a model for NRC evaluation of industry programs, is presented. The model is consistent with current publically stated NRC policy, with the approach being followed by the Institute for Nuclear Power Operations, and with current training technology. Checklists to be used by NRC evaluators to assess training programs for NPP control-room personnel are proposed which are based on this model.

  8. Evaluation of training programs and entry-level qualifications for nuclear-power-plant control-room personnel based on the systems approach to training

    International Nuclear Information System (INIS)

    This report summarizes results of research sponsored by the US Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research to initiate the use of the Systems Approach to Training in the evaluation of training programs and entry level qualifications for nuclear power plant (NPP) personnel. Variables (performance shaping factors) of potential importance to personnel selection and training are identified, and research to more rigorously define an operationally useful taxonomy of those variables is recommended. A high-level model of the Systems Approach to Training for use in the nuclear industry, which could serve as a model for NRC evaluation of industry programs, is presented. The model is consistent with current publically stated NRC policy, with the approach being followed by the Institute for Nuclear Power Operations, and with current training technology. Checklists to be used by NRC evaluators to assess training programs for NPP control-room personnel are proposed which are based on this model

  9. Power Balance Control in an AC/DC/AC Converter for Regenerative Braking in a Two-Voltage-Level Flywheel-Based Driveline

    Directory of Open Access Journals (Sweden)

    Janaína G. Oliveira

    2011-01-01

    Full Text Available The integration of a flywheel as a power handling can increase the energy storage capacity and reduce the number of battery charge/discharge cycles. Furthermore, the ability of recovering energy of the vehicle during breaking can increase the system efficiency. The flywheel-based all-electric driveline investigated here has its novelty in the use of a double-wound flywheel motor/generator, which divides the system in two different voltage levels, enhancing the efficiency of the electric driveline. The connection of two AC electrical machines (i.e., the flywheel and the wheel motor with different and variable operation frequency is challenging. A power matching control applied to an AC/DC/AC converter has been implemented. The AC/DC/AC converter regenerates the electric power converted during braking to the flywheel machine, used here as power handling device. By controlling the power balance, the same hardware can be used for acceleration and braking, providing the reduction of harmonics and robust response. A simulation of the complete system during braking mode has been performed both in Matlab and Simulink, and their results have been compared. The functionality of the proposed control has been shown and discussed, with full regeneration achieved. A round-trip efficiency (wheel to wheel higher than 80% has been obtained.

  10. The level of air pollution in the impact zone of coal-fired power plant (Karaganda City) using the data of geochemical snow survey (Republic of Kazakhstan)

    Science.gov (United States)

    Adil'bayeva, T. E.; Talovskaya, A. V.; Yazikov, Ye G.; Matveenko, I. A.

    2016-09-01

    Coal-fired power plants emissions impact the air quality and human health. Of great significance is assessment of solid airborne particles emissions from those plants and distance of their transportation. The article presents the results of air pollution assessment in the zone of coal-fired power plant (Karaganda City) using snow survey. Based on the mass of solid airborne particles deposited in snow, time of their deposition on snow at the distance from 0.5 to 4.5 km a value of dust load has been determined. It is stated that very high level of pollution is observed at the distance from 0.5 to 1 km. there is a trend in decrease of dust burden value with the distance from the stacks of coal-fired power plant that may be conditioned by the particle size and washing out smaller ash particles by ice pellets forming at freezing water vapour in stacks of the coal-fired power plant. Study in composition of solid airborne particles deposited in snow has shown that they mainly contain particulates of underburnt coal, Al-Si- rich spheres, Fe-rich spheres, and coal dust. The content of the particles in samples decreases with the distance from the stacks of the coal-fired power plant.

  11. 提高基层供电服务满意度策略分析%Strategy analysis of improving service satisfaction of basic level power supply

    Institute of Scientific and Technical Information of China (English)

    张立娟; 张克众

    2015-01-01

    根据对基层供电企业供电服务满意度测评结果,分析当前基层供电服务工作中存在的不足,研究畅通服务渠道、建立更亲切友好的服务界面、提升服务品质的策略,以实现客户对供电服务的满意度和社会美誉度的持续提高,进而提升电网企业核心竞争力。%According to the power supply service satisfaction survey results of basic level power supply enterprises, the article analyzes the current shortcomings in the primary power supply in the service work, studies and establishes smooth service channels and more friendly service interface, to improve the service quality and customer satisfaction. It also achieves power supply service and social reputation and enhances the core competitiveness of power grid enterprises.

  12. Declining LO-Confederation Membership and its Consequences on Power-Dependence Relation and Wage Levels in Two Danish Trade Unions

    OpenAIRE

    Schjøttz, Frederik

    2014-01-01

    The scope of this semester assignment will assess the phenomenon and the causes of declining membership in LO confederation unions, the impact this could have on wage levels in Denmark and the effect on power-dependence relations between two trade unions and their respective employer unions. Having previously assessed recruitment strategies and motivations for recruitment of potential trade union members, I now wish to assess the phenomenon of the declining rate of memberships on a grande...

  13. Electric Vehicle to Power Grid Integration Using Three-Phase Three-Level AC/DC Converter and PI-Fuzzy Controller

    Directory of Open Access Journals (Sweden)

    Khairy Sayed

    2016-07-01

    Full Text Available This paper presents the control and simulation of an electric vehicle (EV charging station using a three-level converter on the grid-side as well as on the EV-side. The charging station control schemes with three-level AC/DC power conversion and a bidirectional DC/DC charging regulator are described. The integration of EVs to the power grid provides an improvement of the grid reliability and stability. EVs are considered an asset to the smart grid to optimize effective performance economically and environmentally under various operation conditions, and more significantly to sustain the resiliency of the grid in the case of emergency conditions and disturbance events. The three-level grid side converter (GSC can participate in the reactive power support or grid voltage control at the grid interfacing point or the common coupling point (PCC. A fuzzy logic proportional integral (FL-PI controller is proposed to control the GSC converter. The controllers used are verified and tested by simulation to evaluate their performance using MATLAB/SIMULINK. The comparison of a PI-controller and a PI-Fuzzy controller for the EV charging station shows the effectiveness of the proposed FL-PI controller over conventional PI controller for same circuit operating conditions. A good performance for PI-Fuzzy in terms of settling time and peak overshoot can observed from the simulation results.

  14. Energy matching and optimization analysis of waste to energy CCHP (combined cooling, heating and power) system with exergy and energy level

    International Nuclear Information System (INIS)

    CCHP (combined cooling, heating and power) system as a poly-generation technology has received an increasing attention in field of small scale power systems for applications ranging from residence to utilities. It will also play an important role in waste to energy application for megacities. However, how to evaluate and manage energy utilization of CCHP scientifically remains unclear. In this paper, energy level and exergy analysis are implemented on energy conversion processes to reveal the variation of energy amount and quality in the operation of CCHP system. Moreover, based on the energy level analysis, the methodology of energy matching and optimization for the CCHP system is proposed. By this method, the operational parameters of CCHP system can be deduced to obtain an efficient performance and proper energy utilization. It will be beneficial to understand and operate the CCHP system, and to provide a guiding principle of the energy conversion and management for the CCHP system. - Highlights: • Energy level is implemented to reveal the energy variation of CCHP system. • A mathematical energy level analysis model of CCHP system is proposed. • By energy level analysis between supply and demand, optimal zone is obtained. • This study will be useful for energy matching and optimization of CCHP system

  15. Reactive power control with CHP plants - A demonstration

    DEFF Research Database (Denmark)

    Nyeng, Preben; Østergaard, Jacob; Andersen, Claus A.;

    2010-01-01

    In this project the potential for ancillary services provision by distributed energy resources is investigated. Specifically, the provision of reactive power control by combined heat and power plants is examined, and the application of the new standard for DER communication systems, IEC 61850...... lines to underground cables has changed the reactive power balance, and third, the TSO has introduced restrictions in the allowed exchange of reactive power between the transmission system and distribution grids (known as the Mvar-arrangement). The demonstration includes a CHP plant with an electric...... power rating of 7.3 MW on two synchronous generators. A closed-loop control is implemented, that remote controls the CHP plant to achieve a certain reactive power flow in a near-by substation. The solution communicates with the grid operator’s existing SCADA system to obtain measurements from...

  16. A new balancing three level three dimensional space vector modulation strategy for three level neutral point clamped four leg inverter based shunt active power filter controlling by nonlinear back stepping controllers.

    Science.gov (United States)

    Chebabhi, Ali; Fellah, Mohammed Karim; Kessal, Abdelhalim; Benkhoris, Mohamed F

    2016-07-01

    In this paper is proposed a new balancing three-level three dimensional space vector modulation (B3L-3DSVM) strategy which uses a redundant voltage vectors to realize precise control and high-performance for a three phase three-level four-leg neutral point clamped (NPC) inverter based Shunt Active Power Filter (SAPF) for eliminate the source currents harmonics, reduce the magnitude of neutral wire current (eliminate the zero-sequence current produced by single-phase nonlinear loads), and to compensate the reactive power in the three-phase four-wire electrical networks. This strategy is proposed in order to gate switching pulses generation, dc bus voltage capacitors balancing (conserve equal voltage of the two dc bus capacitors), and to switching frequency reduced and fixed of inverter switches in same times. A Nonlinear Back Stepping Controllers (NBSC) are used for regulated the dc bus voltage capacitors and the SAPF injected currents to robustness, stabilizing the system and to improve the response and to eliminate the overshoot and undershoot of traditional PI (Proportional-Integral). Conventional three-level three dimensional space vector modulation (C3L-3DSVM) and B3L-3DSVM are calculated and compared in terms of error between the two dc bus voltage capacitors, SAPF output voltages and THDv, THDi of source currents, magnitude of source neutral wire current, and the reactive power compensation under unbalanced single phase nonlinear loads. The success, robustness, and the effectiveness of the proposed control strategies are demonstrated through simulation using Sim Power Systems and S-Function of MATLAB/SIMULINK.

  17. A new balancing three level three dimensional space vector modulation strategy for three level neutral point clamped four leg inverter based shunt active power filter controlling by nonlinear back stepping controllers.

    Science.gov (United States)

    Chebabhi, Ali; Fellah, Mohammed Karim; Kessal, Abdelhalim; Benkhoris, Mohamed F

    2016-07-01

    In this paper is proposed a new balancing three-level three dimensional space vector modulation (B3L-3DSVM) strategy which uses a redundant voltage vectors to realize precise control and high-performance for a three phase three-level four-leg neutral point clamped (NPC) inverter based Shunt Active Power Filter (SAPF) for eliminate the source currents harmonics, reduce the magnitude of neutral wire current (eliminate the zero-sequence current produced by single-phase nonlinear loads), and to compensate the reactive power in the three-phase four-wire electrical networks. This strategy is proposed in order to gate switching pulses generation, dc bus voltage capacitors balancing (conserve equal voltage of the two dc bus capacitors), and to switching frequency reduced and fixed of inverter switches in same times. A Nonlinear Back Stepping Controllers (NBSC) are used for regulated the dc bus voltage capacitors and the SAPF injected currents to robustness, stabilizing the system and to improve the response and to eliminate the overshoot and undershoot of traditional PI (Proportional-Integral). Conventional three-level three dimensional space vector modulation (C3L-3DSVM) and B3L-3DSVM are calculated and compared in terms of error between the two dc bus voltage capacitors, SAPF output voltages and THDv, THDi of source currents, magnitude of source neutral wire current, and the reactive power compensation under unbalanced single phase nonlinear loads. The success, robustness, and the effectiveness of the proposed control strategies are demonstrated through simulation using Sim Power Systems and S-Function of MATLAB/SIMULINK. PMID:27018144

  18. Differences in Power Structures Regarding Access to Natural Resources at the Village Level in Central Sulawesi (Indonesia

    Directory of Open Access Journals (Sweden)

    Jan Barkmann

    2008-01-01

    Full Text Available The mountain forests of the Indonesian province of Central Sulawesi include core areas of the global Wallacea biodiversity “hotspot”. Remote sensing data indicated that deforestation rates around Central Sulawesi’s Lore-Lindu National Park differ more strongly between villages than could be explained by differences in the individual characteristics of the village households as assessed by quantitative village censuses. This setting provided the background for a study into inter-village differences in power structures regarding access to natural resources. Our results are abstracted from 3*10 semi-structured, qualitative interviews with key informants from the leading groups of autochthonous and migrant households of three contrasting villages. In village A, nearly feudal power relationships are exerted by a group of local “first settler” families that dominate formal village leadership as well as the influential Council of Traditional Leaders (Lembaga Adat, and that restrict deforestation and land transactions. No such institutional restrictions exist in village C. Traditional power relationships are replaced by economic power based on petty capitalist type production of the international agricultural commodity cocoa. Deforestation is muchhigher in village C. In village B, traditional institutions and power structures still appear in place although land transactions are less restricted than in village A, resulting also in high deforestation rates. While contrasting problematic social effects, our study highlights the potential efficacy of traditional institutions in the regulation of access to resources. ----- Die Bergregenwälder Zentralsulawesis sind Teil des globalen Wallacea-Biodiversität-"Hotspots" und beheimaten viele endemische Tier- und Pflanzenarten. Die Entwaldung im Bereich des dortigen Lore-Lindu Nationalparks unterscheidet sich zwischen umliegenden Dörfern stärker, als dies durch quantitative Haushaltsdaten zu erkl

  19. Arc Power Limit and Distribution on the Large Negative Ion Source Based on JT-60 NNBI

    Institute of Scientific and Technical Information of China (English)

    LEIGuangjiu; N.Umeda; M.Kawai; T.Yamamoto; M.Kuriyama; T.Ohga; N.Ebisawa; T.Yamazaki; M.Kusaka; K.Kikuchi; S.Hikida; K.Usui; M.Kazawa; S.Numazawa; K.Mogaki; A.Honda; F.Satoh; S.Norio; K.Ooshima

    2001-01-01

    The target of the large negative ion source based on neutral beam injection (N-NBI) is to produce neutral beam current of 22 A and beam power of 10 MW at 500 keV with duration time of 10 s. Since it was successfully operated in 1996, the 5.3 MW neutral beam power at 380 keV with duration time of 3 s has been achieved. In recent years improving and enhancing the beam power are going on. Several reasons such as plasma non-uniformity, higher beam density at the upper region in the beam profile,

  20. Interpersonal Influence Process in Real Life Counseling: Investigating Client Perceptions, Counselor Experience Level, and Counselor Power over Time.

    Science.gov (United States)

    Heppner, P. Paul; Heesacker, Martin

    1982-01-01

    Examined interpersonal influence processes within an actual counseling context over an average of eight sessions. Results indicated that counselor experience level did not affect client perceptions of the counselor and perceived counselor expertise, attractiveness, and trustworthiness did change over time, but not in the same direction. (Author)

  1. 14C levels in the vicinity of the Fukushima Dai-ichi Nuclear Power Plant prior to the 2011 accident

    DEFF Research Database (Denmark)

    Xu, Sheng; Cook, Gordon T.; Cresswell, Alan J.;

    2016-01-01

    A 50-year-old Japanese cedar (Cryptomeria japonica) from Okuma, ∼1 km southwest of the Fukushima Dai-ichi Nuclear Power Plant, was cored and each annual ring was analysed for 14C. The 14C specific activity values varied from 330.4 Bq kg−1 C in the tree ring formed in 1971 to 231.2 Bq kg−1 C...... ingestion pathway in the study location. The primary wind direction is east-southeast/southeast with a frequency of ∼30%, in comparison to ∼20% frequency for the direction of the site under study (north-northeast/northeast). This would tend to indicate a similar magnitude of additional effective dose...... or that the prevailing wind during the short period of release (11th–25th March 2011) was not in the direction of Okuma....

  2. Detailed description of an SSAC at the facility level for light water moderated (off-load refueled) power reactor facilities

    International Nuclear Information System (INIS)

    This report is intended to provide the technical details of an effective State Systems of Accounting for and Control of Nuclear Material (SSAC) which Member States may use, if they wish, to establish and maintain their SSACs. It is expected that systems designed along the lines described would be effective in meeting the objectives of both national and international systems for nuclear material accounting and control. This document accordingly provides a detailed description of a system for the accounting for and control of nuclear material in an off-load refueled light water moderated power reactor facility which can be used by a facility operator to establish his own system to comply with a national system for nuclear material accounting and control and to facilitate application of IAEA safeguards. The scope of this document is limited to descriptions of the following elements: (1) Nuclear Material Measurements; (2) Measurement Quality; (3) Records and Reports; (4) Physical Inventory Taking; (5) Material Balance Closing

  3. State of Charge-Based Active Power Sharing Method in a Standalone Microgrid with High Penetration Level of Renewable Energy Sources

    Directory of Open Access Journals (Sweden)

    Yun-Su Kim

    2016-06-01

    Full Text Available Standalone microgrids, which are mainly constructed on island areas have low system inertia, may result large frequency deviations even for small load change. Moreover, increasing penetration level of renewable energy sources (RESs into standalone microgrids makes the frequency stability problem even worse. To overcome this problem, this paper proposes an active power sharing method with zero frequency deviations. To this end, a battery energy storage system (BESS is operated as constant frequency (CF control mode, whereas the other distributed generations (DGs are operated as an active and reactive power (PQ control mode. As a result, a state of charge (SOC of the BESS is changed as the system load varies. Based on the SOC deviation, DGs share the load change. The SOC data is assumed to be sent via communication system, hence the communication time delay is considered. To enhance reliability, controllers of DGs are designed to take account of the failure of communication system. The simulation results show that active power can be shared among DGs according to desired ratio without frequency deviations even for large variation of output power of RESs.

  4. A high-quality multi-level voltage source inverter suitable for high power/high voltage applications

    International Nuclear Information System (INIS)

    In this paper new magnitudes for D C side capacitors' voltages of a multi level voltage source inv enter are presented. Using these magnitudes of D C side capacitors voltage allow generation of Σ3k steps of A C output voltage by cascade connection of only N single-phase full bridge inverter. This subject has resulted in almost sinusoidal output voltage wave form. Approximated equal area pulse amplitude modulation technique is used to calculate the duration of each step of voltage, which has resulted in reduction of complexity of control circuit. A simple closed-loop controller is developed for controlling the voltage of D C side capacitors. Harmonic analysis and capacitor calculations are presented, too. Simulation results have been used to verify the overall operation of the proposed multi level voltage source inverter in feeding a R-L load with a stepped sinusoidal wave form

  5. Low-level laser (light) therapy (LLLT) on muscle tissue: performance, fatigue and repair benefited by the power of light

    OpenAIRE

    Ferraresi, Cleber; Hamblin, Michael R.; Nivaldo A. Parizotto

    2012-01-01

    The use of low level laser (light) therapy (LLLT) has recently expanded to cover areas of medicine that were not previously thought of as the usual applications such as wound healing and inflammatory orthopedic conditions. One of these novel application areas is LLLT for muscle fatigue and muscle injury. Since it is becoming agreed that mitochondria are the principal photoacceptors present inside cells, and it is known that muscle cells are exceptionally rich in mitochondria, this suggests th...

  6. Self Esteem in Making Decision and The Interpretational Power of Decisionmaking Styles of Teacher Candidates Emotional Intelligence Levels

    OpenAIRE

    Yılmaz, Ercan; ALTINOK, Vicdan

    2010-01-01

    The aim of this study was to seek out to what extend the emotional intelligence levels of university students who are to be teachers explained their self-esteem in decision making and decision making styles. The research group of this study composed of totally 415 senior students of education faculties of Selcuk University who were chosen according to random clustering samples. The findings of the study proved that there is a significant positive correlation between all sub-dimensions of emot...

  7. Body fat distribution in the Finnish population: environmental determinants and predictive power for cardiovascular risk factor levels.

    OpenAIRE

    Marti, B; Tuomilehto, J; Salomaa, V.; Kartovaara, L.; Korhonen, H.J.; Pietinen, P.

    1991-01-01

    STUDY OBJECTIVE--The aim was to examine (1) whether health habits are associated with body fat distribution, as measured by the waist/hip girth ratio, and (2) to what extent environmental factors, including anthropometric characteristics, explain the variability in levels of cardiovascular risk factors. DESIGN--The study was a population based cross sectional survey, conducted in the spring of 1987 as a part of an international research project on cardiovascular epidemiology. SETTING--The sur...

  8. Spectral shape deformation in inverse spin Hall voltage in Y{sub 3}Fe{sub 5}O{sub 12}|Pt bilayers at high microwave power levels

    Energy Technology Data Exchange (ETDEWEB)

    Lustikova, J., E-mail: lustikova@imr.tohoku.ac.jp; Shiomi, Y.; Handa, Y. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Saitoh, E. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); CREST, Japan Science and Technology Agency, Tokyo 102-0076 (Japan); Advanced Science Research Center, Japan Atomic Energy Agency, Tokai 319-1195 (Japan)

    2015-02-21

    We report on the deformation of microwave absorption spectra and of the inverse spin Hall voltage signals in thin film bilayers of yttrium iron garnet (YIG) and platinum at high microwave power levels in a 9.45-GHz TE{sub 011} cavity. As the microwave power increases from 0.15 to 200 mW, the resonance field shifts to higher values, and the initially Lorentzian spectra of the microwave absorption intensity as well as the inverse spin Hall voltage signals become asymmetric. The contributions from opening of the magnetization precession cone and heating of YIG cannot well reproduce the data. Control measurements of inverse spin Hall voltages on thin-film YIG|Pt systems with a range of line widths underscore the role of spin-wave excitations in spectral deformation.

  9. Solution of the level of approximation analytic formula of hydrogen-like atom for the Debye shielding potential by means of the power series

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The first-order revision and the approximation analytical formula of the energy levels for hydrogen-like atoms in condition of the Debye shielding potential are achieved by means of the Rayleigh―Schrdinger perturbation theory and the power series;meanwhile,the corresponding recurrence relations are got with the use of the solution of power series. Basic on mentioned above and with the use of energy consistent method, the equivalent value of second-order revision in condition of the Debye shielding potential as well be got and the result is compared with the data obtained by the numerical method. Beside, the critical bond-state and corresponding cut off of conditions are discussed.

  10. Power electronic topology and switching-concept for identification of the grid impedance at medium-voltage-level; Leistungselektronisches Schaltungskonzept zur Identifikation der Netzimpedanz auf der Mittelspannungsebene

    Energy Technology Data Exchange (ETDEWEB)

    Do, Thanh Trung; Jordan, Michael; Langkowski, Hauke; Schulz, Detlef [Helmut-Schmidt-Univ., Hamburg (Germany). Professur fuer Elektrische Energiesysteme; Leutwyler, Reto [ABB Switzerland Ltd., Lenzburg (Switzerland). Semiconductors

    2011-07-01

    The grid impedance at a point of common coupling (PCC) is an important parameter for grid integration of Renewable Energies, because it determines the maximum input power capacity of the corresponding PCC. The grid impedance is time and frequency dependent, which makes an analytical or simulative identification challenging. Therefore in practise the data obtained from these calculations are often incorrect and do not reflect the real grid structure. In order to determine the grid impedance more accurately the Helmut-Schmidt-University is developing a novel measurement device to identify the time and frequency dependent grid impedance on the medium-voltage-level up to 20 kVrms. For the application in medium-voltage-grids a special switching concept with high voltage thyristors and innovative presspack-IGBTs has been developed in cooperation with ABB Switzerland Ltd./Semiconductors. This contribution presents the basic grid impedance measurement method and its realization with power electronic components. (orig.)

  11. THE EFFECT OF CAFFEINE CONSUMPTION ON THE NON-AEROBIC POWER, THE FATIGUE INDEX AND THE BLOOD LACTATE LEVELS IN THE MALE ATHLETE STUDENTS

    Directory of Open Access Journals (Sweden)

    Ranjbar Rouhola

    2010-06-01

    Full Text Available The main purpose of this research is to study the effect of caffeine consumption on the non-aerobic power, the fatigue index and the blood lactate levels in the male athlete students. Therefore, 16 individuals with the average weight (68/1 +_ 9/1kg, height (1/73+_7cm, and age (24+_2 years were selected based on the simple-randomized method from among volunteer participants, and they were divided as match pairs, based on pre-examined fatigue index, into the two groups of caffeine (n=8 and placebo (n=8. Subjects were asked to refrain from having any intensive physical activity 24 hours before the test starts and avoid eating or drinking any caffeine foods or drinks 48 hours before the test. The primary RAST test (pre-test was performed at least 4 hours after having a meal, and then the individuals blood lactate levels was measured after 6 minutes of the test. The secondary RAST test was done after a week exactly like the first session. The subjects continued caffeine consumption as usual and interrupt it 48 hours prior to the next test. In post-test, the subjects took 6mg caffeine or placebo in the form of gelatin capsules per one kilogram of their weight one hour prior to the test. The analysis of the result, with applying the statistical t-test method (p≤0.05 to the dependent and independent groups, showed that consumption of caffeine has a significant positive effect on average power; minimum power and fatigue index, while it does not have any significant effect on maximum power and the amount of blood lactate. It seems that caffeine consumption is effective in the recovery of fast short-term shuttle activities.

  12. KAPS level-1 PSA- analysis of 6.6 kV class-IV power supply failure as initiating event

    International Nuclear Information System (INIS)

    Full text: For Kakrapar atomic power station (KAPS) level-l probabilistic safety analysis (PSA) studies failure of 6.6 kV CL-IV power supply system resulting from failure of both the routes of class-IV buses viz., route via buses A, B, C and route via buses F, G, H is considered as one of the initiating events for analysis. This can happen due to grid problems or due to combinations of component failures from both the routes. This event is one of the most important transient events in station transient analysis as it could lead to scenarios like station blackout depending upon the availability of emergency power supply system i.e.the diesel generator system. Upon failure of class-IV power, reactor trips on no PCP on either side followed by high PHT pressure trip. Following this event if class III is available, no safety system gets affected and the mode of decay heat removal and long-term reactivity control are same as normally followed. If class-III fails, reactor has to be crash cooled and fire water should be injected to SGs for decay heat removal. Class-IV failure followed by class-III failure leads to a station blackout scenario in which a number of front line systems become available. Event tree was developed showing the mitigating functions/ systems required sequentially for safe termination of the initiating event (IE). To estimate the accident sequence frequencies the success and failure probabilities of these mitigating functions/ systems were calculated by fault tree methods. The IE frequency estimates have been derived from experience at KAPS station. For component failure probabilities a judicious mix of generic and plant specific data was used. The details and results of the assessment are presented in the paper

  13. [Hygienic problems in the location of modern wind electric power stations in their design].

    Science.gov (United States)

    Kireeva, I S; Makhniuk, V M; Akimenko, V Ia; Dumanskiĭ, Iu D; Semashko, P V

    2013-01-01

    Hygienic aspects of the placement of wind power plants (WPP) in connection with the intensive development of wind power and the lack of systematic information on their effects of the environment and living conditions of the population are becoming more actual. In the article there are considered results of the sanitary-epidemiological expertise of the construction project of three modern large wind farm (the South - Ukrainian, Tiligulskaya and Pokrovskaya) with a total capacity offrom 180 to 500 MW of wind farms with 2.3 MW power generators of wind turbines. It is shown that in the process of wind farm construction a contamination of the environment (air soil, ground water) may take place due to the working of construction equipment and vehicle, excavation, welding and other operations, in the exploitation of wind farm there can be created elevated levels of acoustic and electromagnetic pollution in the neighborhood and emergencies with the destruction of WPP in adverse weather conditions. Based on the calculations presented in the projects, and the analysis of data on the impact offoreign windfarm on the environment it was found that the limiting factor of the influence is the wind farm noise pollution in the audio frequency range that extends beyond the territory of wind fields, electromagnetic radiation is recorded within the hygienic standards and below only in the immediate vicinity of its sources (electrical equipment and power lines). For considered modern wind farms there was grounded sanitary protective zone with dimensions of 700 mfrom the outermost wind turbines by the noise and it was recommended compliance distance of200 mfrom the wind turbine to limit any activity and people staying in times of possible emergency situations in adverse weather conditions.

  14. Radioactive contamination levels in China and health evaluation following radioactive release from Soviet Chernobyl Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    For the purpose of evaluating radiological effects in China and protecting population from possible consequences of Soviet Chernobyl nuclear power plant accident, the national network of environmental radioactive monitoring stations in China started emergency monitoring since May 1st, 1986. From May 1st to the end of July, 131I, 137Cs and other man-made radionuclides in some environmental media were found in large amounts. 131I was detected obviously in daily deposition, surface water, growing leafy vegetables, fresh milk and sheep thyroid samples. It is proved that radioactive fallout from Soviet Chernobyl accident has spreaded in atmosphere over the territory of China; so, the environment has been contaminated. Thyroid dose for individuals of general public in China was estimated. The effective dose equivalents for adults are lower than 2 μSv, for infants lower than 30 μSv; they are low as compared with 'Basic Health Standards for Radiological Protection' in China. The emergency sanitary protective measures were considered unnecessary

  15. Level 1 and 2 probabilistic safety assessment technology study and its application in the design of CHASHMA nuclear power plant unit2

    International Nuclear Information System (INIS)

    The software used for Level 1,2 and 3 probabilistic safety assessment (PSA) has been developed by technique introduction as well as independent research. It has been studied and applied to integrating the design of CHASHMA Nuclear Power Plant unit 2 (C-2) with the Level 1 and 2 PSA technology, which include the analysis of initiating events, event trees, fault trees, dependency analysis, human reliability analysis, database analysis, event sequence quantification, plant damage state analysis, accident progression and containment response analysis, source term analysis, large early release frequency (LERF) analysis, uncertainty analysis, importance/sensitivity analysis, applications during design phase, and so on. The model of Level 1 and 2 PSA has been established for C-2. In the meantime, several significant design improvement has been implemented in the process of C-2 design based on the PSA insights, such as that of isolation valves on the mini-flow line of the safety injection pump and spray pump, reciprocating charging pump in chemical and volume control system, essential service water system, etc. Thus, the figures of merit for C-2 for the internal events at power operating condition have been achieved with 7.25E-6/ry for core damage frequency (CDF), 3.24E-07/ry for LERF. The C-2 PSA has not only justified the balance of its design, but also provided the probability assessment information for evaluating the optimization of C-2 design and operation strategies, efficiently reducing the risk of severe accidents. (authors)

  16. Pre operational levels of 137Cs and 90Sr in seawater and sea foods in Gulf of Mannar near Kudankulam Nuclear Power Plant

    International Nuclear Information System (INIS)

    The first unit of Kudankulam Nuclear Power Project (KKNPP) attained first criticality on July 13, 2013 and synchronized to the grid on October 22, 2013. The first unit achieved the full rated power of 1000 MWe on June 7, 2014. The second unit of KKNPP is under advanced stage of commissioning and hot run of the plant is expected shortly. Commercial operational of the first unit is expected soon. It is imperative to establish the pre operational levels of Fall out nuclides like 137Cs and 90Sr in and around Kudankulam site, especially sea waters and sea food samples as these nuclides are produced in the reactor as fission products. Nevertheless, they are retained in the fuel matrix itself as the reactors host a multiple layered barrier to prevent the escape of these radionuclides into the environment by adopting the philosophy of defense in depth. Benchmarking the levels of these nuclides in the aquatic domain will help in future comparison of the levels of these nuclides after the plants start operation in addition to generating the regional database in south eastern tip of the sea

  17. Investigation on the use digital controls instead of PID analog controls in the level control of steam generators of nuclear power PWR

    International Nuclear Information System (INIS)

    The aim of this study is to identify current alternatives for the implementation of digital controllers in the level control of steam generators of nuclear power PWR (Pressurized Water Reaetor). It is intended to identify the types of digital controls that are available from the theoretical and conceptual viewpoints for this purpose. We investigate the advantages and disadvantages of each controller model. From this assessment are pointed the most suitable models in hierarchical scale. This evaluation also serves to suggest possible types of control installation as a whole, where the level control of the steam generators becomes just one of many controls that are part of the plant. In this case, the use of digital controls allows the non-linear and multivariable treatment which is characteristic of complex systems, such as the nuclear power generation. The treatment of nonlinearities and multivariable aspects allows a more detailed study of the stability of these plants when they are subject to transients or several accidents, such as the case of losing external power of transients. In the specific case of steam generators, the instabilities result from the emergence of the shrink and swell phenomenas, depending on the load variations of thermonuclear plant. The application of several types and digital controllers, considering these inherent characteristics of the level control of steam generators, allows to infer which types of controllers are more appropriate to treat instabilities of this type and to make conjectures in its use for the cases of more complex instabilities, considering the integration of all nucleus-plant controls.

  18. Natural radioactive level in coal and ash and building material products from coal-fired power plants in Beijing

    International Nuclear Information System (INIS)

    The authors report the methods and results of survey on content of 226Ra, 232Th and 40K in samples of coal, ash from 5 coal-fired power plants in Beijing and ash bricks, air-added concrete from Beijing air-added concrete plant from February to December, 1993. 55 coal Samples, 26 ash Samples, 8 ash brick samples and 8 air-added concrete samples were collected. These samples were analysed by type FH-1936 low background γ-spectrometer. The average value of 226Ra, 232Th and 40K of coal is 28.9, 35.9 and 80.4 Bq/kg, respectively; 101, 110 and 347 Bq/kg, for ash; 47.6, 72.9 and 288 Bq/kg, for ash brick and 47.8, 70.1 and 216 Bq/kg for air-added concrete, respectively. In addition, γ radiation dose rate inside buildings of workers, dwelling houses of the Beijing air-added concrete plant made of ash building materials were investigated and analysed. The range and the average value of 8 measurement values is (67.4-84.7) nGy/h and 78.2 nGy/h, respectively. It approaches to the average value inside bungalow of bricks and a building of two or more storeys made of bricks and concrete in Beijing and within normal range. The results show that it might not cause obviously increase of γ radiation dose rate inside building when the ash were rationally used as the raw materials of building

  19. Implementation of a Sage-Based Stirling Model Into a System-Level Numerical Model of the Fission Power System Technology Demonstration Unit

    Science.gov (United States)

    Briggs, Maxwell H.

    2011-01-01

    The Fission Power System (FPS) project is developing a Technology Demonstration Unit (TDU) to verify the performance and functionality of a subscale version of the FPS reference concept in a relevant environment, and to verify component and system models. As hardware is developed for the TDU, component and system models must be refined to include the details of specific component designs. This paper describes the development of a Sage-based pseudo-steady-state Stirling convertor model and its implementation into a system-level model of the TDU.

  20. The PVM (Parallel Virtual Machine) system: Supercomputer level concurrent computation on a network of IBM RS/6000 power stations

    Energy Technology Data Exchange (ETDEWEB)

    Sunderam, V.S. (Emory Univ., Atlanta, GA (USA). Dept. of Mathematics and Computer Science); Geist, G.A. (Oak Ridge National Lab., TN (USA))

    1991-01-01

    The PVM (Parallel Virtual Machine) system enables supercomputer level concurrent computations to be performed on interconnected networks of heterogeneous computer systems. Specifically, a network of 13 IBM RS/6000 powerstations has been successfully used to execute production quality runs of superconductor modeling codes at more than 250 Mflops. This work demonstrates the effectiveness of cooperative concurrent processing for high performance applications, and shows that supercomputer level computations may be attained at a fraction of the cost on distributed computing platforms. This paper describes the PVM programming environment and user facilities, as they apply to hardware platforms comprising a network of IBM RS/6000 powerstations. The salient design features of PVM will be discussed; including heterogeneity, scalability, multilanguage support, provisions for fault tolerance, the use of multiprocessors and scalar machines, an interactive graphical front end, and support for profiling, tracing, and visual analysis. The PVM system has been used extensively, and a range of production quality concurrent applications have been successfully executed using PVM on a variety of networked platforms. The paper will mention representative examples, and discuss two in detail. The first is a material sciences problem that was originally developed on a Cray 2. This application code calculates the electronic structure of metallic alloys from first principles and is based on the KKR-CPA algorithm. The second is a molecular dynamics simulation for calculating materials properties. Performance results for both applicants on networks of RS/6000 powerstations will be presented, and accompanied by discussions of the other advantages of PVM and its potential as a complement or alternative to conventional supercomputers.

  1. An Ergonomic Evaluation of the Illumination Level and the Management Plan to Improve the Working Environment of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Illumination in the working environment is one of the crucial factors that affect worker's psychological status as well as the physiological condition according to each task. Sometimes it affects the results of worker's cognitive, perceptual work performance. In particular, illumination may become a triggering factor to human errors in visual tasks due to visual fatigue through direct influence of vision in NPPs. Illumination includes several visual conditions such as uniformity factor, light distribution, glare, SPD (Surge Protector Device), flicker, illumination system, daylight and window control, in addition to the simple physical aspects of illumination and luminance. These conditions may affect operators' visibility and disillusion level, cause stress, attention, emotion, etc. and they finally affect workers' performance and errors as a result. From the many illumination conditions mentioned above, current work environment evaluation items on illumination are mainly based only on the intensity of illumination, and there is yet no systematic way with evaluation criteria for other factors such as luminance, flickering, etc. In addition, research and development on illumination emphasizes mainly the physical characteristics of illumination, and it is insufficient for the influence studies on human error or work performance that are caused by these factors

  2. An Ergonomic Evaluation of the Illumination Level and the Management Plan to Improve the Working Environment of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Kwang Hyeon; Lee, Yong Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    Illumination in the working environment is one of the crucial factors that affect worker's psychological status as well as the physiological condition according to each task. Sometimes it affects the results of worker's cognitive, perceptual work performance. In particular, illumination may become a triggering factor to human errors in visual tasks due to visual fatigue through direct influence of vision in NPPs. Illumination includes several visual conditions such as uniformity factor, light distribution, glare, SPD (Surge Protector Device), flicker, illumination system, daylight and window control, in addition to the simple physical aspects of illumination and luminance. These conditions may affect operators' visibility and disillusion level, cause stress, attention, emotion, etc. and they finally affect workers' performance and errors as a result. From the many illumination conditions mentioned above, current work environment evaluation items on illumination are mainly based only on the intensity of illumination, and there is yet no systematic way with evaluation criteria for other factors such as luminance, flickering, etc. In addition, research and development on illumination emphasizes mainly the physical characteristics of illumination, and it is insufficient for the influence studies on human error or work performance that are caused by these factors

  3. Power and polarization dependences of ultra-narrow electromagnetically induced absorption (EIA) spectra of 85 Rb atoms in degenerate two-level system

    Science.gov (United States)

    Qureshi, Muhammad Mohsin; Rehman, Hafeez Ur; Noh, Heung-Ryoul; Kim, Jin-Tae

    2016-05-01

    We have investigated ultra-narrow EIA spectral features with respect to variations of polarizations and powers of pump laser beam in a degenerate two-level system of the transition of 85 Rb D2 transition line. Polarizations of the probe laser beam in two separate experiments were fixed at right circular and horizontal linear polarizations, respectively while the polarizations of the pump lasers were varied from initial polarizations same as the probe laser beams to orthogonal to probe polarizations. One homemade laser combined with AOMs was used to the pump and probe laser beams instead of two different lasers to overcome broad linewidths of the homemade lasers. Theoretically, probe absorption coefficients have been calculated from optical Bloch equations of the degenerate two level system prepared by a pump laser beam. In the case of the circular polarization, EIA signal was obtained as expected theoretically although both pump and probe beams have same polarization. The EIA signal become smaller as power increases and polarizations of the pump and probe beams were same. When the polarization of the pump beam was linear polarization, maximum EIA signal was obtained theoretically and experimentally. Experimental EIA spectral shapes with respect to variations of the pump beam polarization shows similar trends as the theoretical results.

  4. Power MOSFET quality and robustness enhancement with a new Q{sub BD} characterization performed at probe-die-wafer level

    Energy Technology Data Exchange (ETDEWEB)

    Pomes, Emilie, E-mail: epomes@laas.fr [CNRS, LAAS, 7 Av. du Colonel Roche, F-31077 Toulouse (France); Universite de Toulouse, UPS, INSA, INP, ISAE, LAAS, F-31077 Toulouse (France); Reynes, Jean-Michel [Freescale Semiconductor SAS, Av. du General Eisenhower, 31023 Toulouse (France); Tounsi, Patrick; Dorkel, Jean-Marie [CNRS, LAAS, 7 Av. du Colonel Roche, F-31077 Toulouse (France); Universite de Toulouse, UPS, INSA, INP, ISAE, LAAS, F-31077 Toulouse (France)

    2012-09-01

    Highlights: Black-Right-Pointing-Pointer We used a new way of electrical characterization with the charge-to-breakdown test. Black-Right-Pointing-Pointer Measurements are performed directly at probe-die-wafer level. Black-Right-Pointing-Pointer An accurate monitor has been developed to evaluate dice quality and reliability. Black-Right-Pointing-Pointer The extrinsic failures responsible for potential rejects can be identified. Black-Right-Pointing-Pointer Process and gate stress impact can be evaluated with the diversion of Q{sub BD} test. - Abstract: The quality of the gate oxide is a central parameter for power MOSFET devices dedicated to automotive applications. Reliability is systematically evaluated through electrical tests. The purpose of this study is to apply the Q{sub BD} test directly at probe-die-wafer level and to correlate its results with reliability test conclusions. In other words, this new kind of Q{sub BD} test is a monitor of power MOSFET robustness which helps identify extrinsic failures and the process steps responsible. In summary, it is an accurate and fast measurement method of identifying weakened parts and enhancing device quality.

  5. Disposal of high-level waste from nuclear power plants in Denmark. Salt dome investigations. v.2

    International Nuclear Information System (INIS)

    The present report deals with the geological investigations performed for determing the feasibility of a repository for high-level waste in a salt dome. It is volume 2 of five volumes that together constitute the final report of the Danish utilities' salt dome investigations. The purpose of the work was to procure a more detailed knowledge of the geology of salt domes in North Jutland on example of Mors. The Mors dome is oval with the two axes of approx. 12.5 km and 8 km respectively. Two deep wells have been drilled into the salt. These wells reach 3400-3500 m below surface. Until a depth of about 3200 m Erslev 2 passes through rock salt of Zechstein 1 which is the oldest evaporite series. However, it could also be interlayed with the slightly younger Zechstein 2. At about 3200 m a marker layer was met with Zechstein 2 salt below. Interpretation of cores and results of downhole electromagnetic and borehole gravimetric measurements show that there is a large area around Erslev 2 which consists of very pure sodium chloride with traces of anhydrite (calcium, sulphate) 1-3%. This area is used for the repository design and safety evaluation. The hydrological conditions existing in the strata above the salt dome (caprock) have been investigated with the help of four hydrogeological wells, placed two each, on two different sites. The cores themselves were taken at various depths in all four holes. With these laboratory methods it has been possible to measure data relevant to hydrology - such as porosity and permeability - as well as geochemistry. (BP)

  6. Development of methods for evaluation of electricity saving and load levelling measures. Part 3: Experimental assessment of the effect of a power conservation campaign

    Energy Technology Data Exchange (ETDEWEB)

    Aalborg Nielsen, H.; Madsen, H. [Danmarks Tekniske Univ., Dept. of Mathematical Modelling (Denmark)

    1997-12-01

    The purpose of the project described in this report is to develop and to investigate methods for estimating effects of power conservation campaigns, and to estimate the effect of a particular campaign. The statistical approach of experimental design, followed by analysis of measurements is applied. Using a method known as cluster analysis prior to the initiation of the campaign, a number of substations for which measurements equipment was installed were combined into groups of highest possible similarity with respect to a number of features. It was decided to perform a campaign on a total of two substations. For this purpose the two groups of highest similarity were selected and one substation was chosen from each group to receive the campaign (the active substations). Since each of the two groups contained two substations this procedure left two substations for comparisons (the control substations). The overall results indicate a 10-12% reduction of the power consumption when carrying out a campaign. However, some difference is observed for the two pairs of active and control substations. Consequently, the extrapolation to other substations of similar kind will be difficult. When measuring the diurnal profile as the relative deviation from the daily level during the cycle, practically no effect of the campaign can be detected. However, the amplitude of the profile measured in units of power consumption depends strongly on the daily level. It is demonstrated that non-parametric and semi non-parametric methods, combined with traditional time series analysis and bootstrapping, are well suited as statistical tools for the analysis of data from these kinds of experiments. (au) EFP-95. 22 refs.

  7. 县级供电企业培训质量控制探讨%Inquiry of Training Quality Control of County-level Power Supply Enterprise

    Institute of Scientific and Technical Information of China (English)

    张威; 苏健祥; 张惠聪

    2012-01-01

    This paper introduces an advanced training management philosophy and proposes training quality control model, by analyzing the common three major errors in the training of quality management. It defines training quality control QOCT quantitative model Q =O×C×T,.and processes system analysis and argument, combining with the actual situation of internal training of the county-level power supply enterprise. To Foshan Sanshui Power Supply Bureau, for example, it describes the practical application of the model QOCT measures, and the results achieved after the execution. It is a bold attempt to innovative for Quality control QOCT training establishment and application of the model. It is a control guidance and reference for quality control training of county-level power supply enterprise.%本文通过分析培训质量管理上常见的三大误区,引入先进培训管理理念,提出培训质量控制模型,并结合县级供电企业内部培训实际情况,定义了培训质量控制的QOCT量化模型Q=O×C×T,并进行了系统分析与论证.本文以佛山三水供电局为例,介绍了QOCT模型的实践应用措施,及执行后取得的成效.QOCT培训质量控制模型的建立与运用,是一次大胆创新的尝试,对县级供电企业的培训质量控制有一定的指导和参考意义.

  8. Comparison of power performance and noise between Aeolus 2 and Naesudden 2

    Energy Technology Data Exchange (ETDEWEB)

    Albers, C.; Hinsch, J.; Gabriel, J.; Klug, H. [Deutsches Windenergie-Institut gGmbH (DEWI), Wilhelmshaven (Germany); Ronsten, G. [Aeronautical Research Inst. of Sweden, Bromma (Sweden); Simonssen, B. [KM Akustikbyraan, Solna (Sweden)

    1996-12-01

    The German Wind Energy Institute DEWI and the Aeronautical Research Institute of Sweden FFA perform comparing measurements at the 3 MW sister turbines Aeolus II and Naesudden II in the framework of WEGA II (CAN-Project). Results exist concerning the comparison of power performance and noise emission. Load measurements have been carried out but no comparing results are available yet. In the case of Aeolus II interesting effects of different meteorological conditions on the power performance have been found. The project will continue till the end of 1996. 6 refs, 12 figs, 1 tab

  9. The effects of incline and level-grade high-intensity interval treadmill training on running economy and muscle power in well-trained distance runners.

    Science.gov (United States)

    Ferley, Derek D; Osborn, Roy W; Vukovich, Matthew D

    2014-05-01

    Despite a paucity of evidence, uphill running has been touted as a sport-specific resistance-to-movement training tactic capable of enhancing metabolic, muscular, and neuromuscular processes in distance runners in ways similar to previously established resistance-to-movement training methods, such as heavy and/or explosive strength training and plyometric training. Therefore, the purpose of this investigation included documenting the effects of incline and level-grade interval treadmill training on indices of running economy (RE) (i.e., oxygen consumption [VO2] and blood lactate [BLa] responses of submaximal running) and muscle power. Thirty-two well-trained distance runners (age, 27.4 ± 3.8 years; body mass, 64.8 ± 8.9 kg; height, 173.6 ± 6.4 cm; and VO2max, 60.9 ± 8.5 ml·min(-1)·kg(-1)) received assignment to an uphill (GHill = 12), level-grade (GFlat = 12), or control (GCon = 8) group. GHill and GFlat completed 12 interval and 12 continuous run sessions over 6 weeks, whereas GCon maintained their normal training. Dependent variables measured before and after training were VO2 and BLa at 2 separate velocities associated with lactate threshold (VLT) (VO2-60% and VO2-80%; and BLa-60% and BLa-80%, respectively); percentage of VO2max at lactate threshold (%VO2max at VLT); muscle power as assessed through a horizontal 5-jump test (5Jmax); and isokinetic knee extension and flexion at 3 angular velocities (90, 180, and 300°·s(-1)). Statistical significance was set to p ≤ 0.05. All groups significantly improved 5Jmax, VO2-60%, VO2-80%, BLa-60%, and BLa-80%. Additionally, GHill and GFlat significantly improved %VO2max at VLT. Other indices of RE and muscle power did not improve. We conclude incline treadmill training effective for improving the components of RE, but insufficient as a resistance-to-movement exercise for enhancing muscle power output.

  10. Power Talk

    DEFF Research Database (Denmark)

    Stefanovic, Cedomir; Popovski, Petar; Angjelichinoski, Marko;

    2015-01-01

    We introduce a novel communication strategy for DC Micro Grids (MGs), termed power talk, in which the devices communicate by modulating the power levels in the DC bus. The information is transmitted by varying the parameters that the MG units use to control the level of the common bus voltage......, while it is received by processing the bus measurements that units perform. This implies that the communication does not require a dedicated modem, but instead it is piggybacked on top of the power electronics. The communication is challenged by the random fluctuations of the voltage level due...

  11. Power Converters and Power Quality

    CERN Document Server

    Kahle, K

    2015-01-01

    This paper discusses the subject of power quality for power converters. The first part gives an overview of most of the common disturbances and power quality issues in electrical networks for particle accelerators, and explains their consequences for accelerator operation. The propagation of asymmetrical network disturbances into a network is analysed. Quantitative parameters for network disturbances in a typical network are presented, and immunity levels for users’ electrical equipment are proposed. The second part of this paper discusses the technologies and strategies used in particle accelerator networks for power quality improvement . Particular focus is given to networks supplying loads with cycling active and reactive power

  12. Methodology for evaluating radiological consequences of the management of very low-level solide waste arising from decommissioning of nuclear power plants

    International Nuclear Information System (INIS)

    In this report a methodology is described, and illustrated by examples, for the evaluation of individual doses and collective dose commitments arising as a result of various management modes for very low-level solid wastes arising from the decommissioning of nuclear power plants. Estimates have been made of the masses of materials activated and contaminated to within three concentration limits, 0.37, 3.7 and 37 Bq g-1, at three times after reactor shutdown, 5 y, 25 y and 100 y. The disposal options considered are shallow land burial, at a municipal landfill site or at the reactor site, and disposal on the seabed in coastal waters or the deep ocean. It is assumed that there is no special treatment to reduce or eliminate the potential radiological hazard. Consideration has also been given to the radiological impact of recycling of contaminated steel. The radiological impacts of all the management options for the wastes considered were found to be small. It may therefore be acceptable to allow such very low-level wastes to be disposal of without special restrictions provided that the level and type of activity of the wastes can be verified. In addition the health detriment cost associated with all the management options is small, so it is likely that other factors such as transport and engineering costs will be more important in final decisions about the management of these wastes

  13. Comparison of Field Measurements and EMT Simulation Results on a Multi-Level STATCOM for Grid Integration of London Array Wind Power Plant

    DEFF Research Database (Denmark)

    Glasdam, Jakob; Kocewiak, Łukasz Hubert; Hjerrild, Jesper;

    2014-01-01

    compensator (STATCOM). Quality measurement data allow the system designer to obtain real-life knowledge on the operating characteristics of the electrical component(s) for various operating scenarios of both the OWPP and the external grid. Furthermore, measurement data constitute an indispensable part...... model of the STATCOM with actual field measurements for a commercial MMCC STATCOM. Furthermore, the paper offers the reader, being a researcher, transmission system operator, converter designer or a WPP developer etc., the unique opportunity to gain in-depth knowledge of the operating characteristics...... distortion level. It is found that the total inter-harmonic distortion (TIHD) index calculated according to IEC Standard 61000-4-7 is useful for assessing possible and undesired control interaction between the power electronic devices (PEDs) in OWPPs. The total harmonic distortion (THD) index, on the other...

  14. Development of plant-level automatic voltage control system for power plant%火电厂厂级自动电压控制系统研制

    Institute of Scientific and Technical Information of China (English)

    翟伟翔; 周宇华; 苏适; 刘友宽

    2011-01-01

    An integrated AVC(Automatic Voltage Control) substation is developed based on existing plant -level automatic generation control system for power plant. The gain of adaptive PID adjuster is properly modified by the dynamic identification of system impedance and the voltage and reactive power are online switched for realizing the error-free and quick adjustment. The bias adjustment algorithm is put forward based on traditional equivalent power factor distribution and reactive power capacity coefficient distribution and the calculation formulas are given. Technical issues of parameter collection, operating mode and protective blocking are described for practical application. Site operation proves that,the proposed AVC system operates stably and reliably with flexible operating manner, good adjustment property and perfect security mechanism.%为保证电网安全、优质、经济运行,将火电厂自动电压控制在现有厂级自动发电控制系统平台上扩展实施,构成了一体化专用子站.通过动态辨识系统阻抗,适当修正自适应PID调节器的增益,进行电压和无功的在线转换,实现无差、快速调节.在传统的等功率因数分配方法与无功容量系数分配方法基础上提出了偏置调整算法,给出了计算公式.针对实际应用,阐述了参数采集、运行模式、闭锁保护等方面的技术问题.通过电厂的实际运行,证明该系统能够稳定可靠地工作,并具有操作方式灵活、调节品质较好、故障与安全处理机制完善等特点.

  15. Geothermal power, policy, and design: Using levelized cost of energy and sensitivity analysis to target improved policy incentives for the U.S. geothermal market

    Science.gov (United States)

    Richard, Christopher L.

    At the core of the geothermal industry is a need to identify how policy incentives can better be applied for optimal return. Literature from Bloomquist (1999), Doris et al. (2009), and McIlveen (2011) suggest that a more tailored approach to crafting geothermal policy is warranted. In this research the guiding theory is based on those suggestions and is structured to represent a policy analysis approach using analytical methods. The methods being used are focus on qualitative and quantitative results. To address the qualitative sections of this research an extensive review of contemporary literature is used to identify the frequency of use for specific barriers, and is followed upon with an industry survey to determine existing gaps. As a result there is support for certain barriers and justification for expanding those barriers found within the literature. This method of inquiry is an initial point for structuring modeling tools to further quantify the research results as part of the theoretical framework. Analytical modeling utilizes the levelized cost of energy as a foundation for comparative assessment of policy incentives. Model parameters use assumptions to draw conclusions from literature and survey results to reflect unique attributes held by geothermal power technologies. Further testing by policy option provides an opportunity to assess the sensitivity of each variable with respect to applied policy. Master limited partnerships, feed in tariffs, RD&D, and categorical exclusions all result as viable options for mitigating specific barriers associated to developing geothermal power. The results show reductions of levelized cost based upon the model's exclusive parameters. These results are also compared to contemporary policy options highlighting the need for tailored policy, as discussed by Bloomquist (1999), Doris et al. (2009), and McIlveen (2011). It is the intent of this research to provide the reader with a descriptive understanding of the role of

  16. Influence of the power level of an ultra-sonic system on dental cavity preparation Influência do nível de potência de um sistema de ultra-som em preparos cavitários

    OpenAIRE

    Érika Botelho Josgrilberg; Murilo de Sousa Guimarães; Cyneu Aguiar Pansani; Rita de Cássia Loiola Cordeiro

    2007-01-01

    The aim of this study was to evaluate the shape of dental cavities made with the CVDentus® system using different ultrasound power levels. One standard cavity was made on the buccal aspect of 15 bovine incisors with a CVDentus® cylindrical bur (82142). The sample was divided into three groups: G1 - ultrasound with power II; G2 - ultrasound with power III; and G3 - ultrasound with power IV. A standardizing device was used to obtain standardized preparations and ultrasound was applied during on...

  17. INSTALLATION OF A POST-ACCIDENT CONFINEMENT HIGH-LEVEL RADIATION MONITORING SYSTEM IN THE KOLA NUCLEAR POWER STATION (UNIT 2) IN RUSSIA

    International Nuclear Information System (INIS)

    This is the final report on the INSP project entitled, ''Post-Accident Confinement High-Level Radiation Monitoring System'' conducted by BNL under the authorization of Project Work Plan WBS 1.2.2.6 (Attachment 1). This project was initiated in February 1993 to assist the Russians in reducing risks associated with the continued operation of older Soviet-designed nuclear power plants, specifically the Kola VVER-440/230 Unit 2, through improved accident detection capability, specifically by the installation of a dual train high-level radiation detection system in the confinement of Unit 2 of the Kola NPP. The major technical objective of this project was to provide, install and make operational the necessary hardware inside the confinement of the Kola NPP Unit 2 to provide early and reliable warning of the release of radionuclides from the reactor into the confinement air space as an indication of the occurrence of a severe accident at the plant. In addition, it was intended to provide hands-on experience and training to the Russian plant workers in the installation, operation, calibration and maintenance of the equipment in order that they may use the equipment without continued US assistance as an effective measure to improve reactor safety at the plant

  18. Behaviour of rocks and mechanical model of leads on the powered supports in a fully mechanized sub-level caving face

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Y. [China Coal Research Institute (China). Beijing Research Institute of Coal Mining

    1997-06-01

    Based on the study of distribution of abutment pressure and movement of overlying rocks and main roof, the decisive effect of the weakened degree of the immediate roof (penetration of shear cracks) and width of the completely failed zone of the top coal in ground pressure manifestation period are studied. Based on which, a mechanical model for calculation of the loads on the powered supports in a sub-level caving face is established. Formulae and examples are given for calculation of loads on the supports by considering the width of the completely plastic zone in top coal in the conditions of different weakness of the immediate roof in case of a long rock beam weighting and semi-arch instability of narrow rock beam. The fracture degree of the immediate roof and the width of the failed zone in top coal are the main criteria for the control of face and in the optimal design of sub-level caving face. 2 refs., 7 figs., 2 tabs.

  19. Wind Power in Georgia

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    opportunity Screening eight sites identified in the Wind Atlas of Georgia (2004) based on a preliminary assessment of the wind power potential, feasibility and construction costs of each site, points to Skra as the most feasible area for pilot development of wind power. The Skra site in Gori/Kareli regions has good (above 7 m/s at 100m) and steady wind resources, minimal land-use and environmental conflicts and high accessibility. An 80m wind measurement mast has recently been put up on the site by a Georgian company. The Skra site is estimated to potentially hold up to 35 3MW turbines (90m rotor diameter) or 45 2MW turbines (80m rotor diameter). The total capacity of the wind farm would thus be 105MW or 90MW respectively. A preliminary estimation for the annual energy production of the wind farm using 2,500 full-load-hours, gives production estimations of 260 GWh for a 105MW and 225 GWh for a 90MW wind farm on the site. Investment cost of the wind farm is estimated to be roughly 1.5 MEuro/MW, which amounts to 158 MEuro for a 105MW farm and 135 MEuro for a 90 MW farm. Several stakeholders in Georgia have expressed interest in using second hand turbines in order to reduce investment costs. Most available used turbines on the market are of sizes less than 2MW and the prize vary significantly depending especially on the capacity, age and make of the turbine. Other interesting sites in Georgia to explore further with an aim for wind power development include Chorokhi, Kutaisi, Samgori and Yagludja.(auth)

  20. {sup 14}C emission from Swedish nuclear power plants and its effect on the {sup 14}C levels in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Stenstroem, K.; Erlandsson, Bengt; Hellborg, R.; Kiisk, M.; Persson, Per [Lund Univ. (Sweden). Dept. of Nuclear Physics; Mattsson, Soeren; Thornberg, C. [Lund Univ., Malmoe (Sweden). Dept. of Radiation Physics; Skog, G. [Lund Univ. (Sweden). Dept. of Quaternary Geology

    2000-02-15

    The radionuclide {sup 14}C is produced in all types of nuclear reactors mainly by neutron induced reactions in oxygen ({sup 17}O), nitrogen ({sup 14}N) and carbon ({sup 13}C). Part of the {sup 14}C created is continuously released during normal operation as airborne effluents in various chemical forms (such as CO{sub 2}, CO and hydrocarbons) to the surroundings. Because of the biological importance of carbon and the long physical half-life of {sup 14}C, it is of interest to measure the releases and their incorporation into living material. The {sup 14}C activity concentrations in annual tree rings and air around two Swedish nuclear power plants (Barsebaeck and Forsmark) as well as the background {sup 14}C activity levels from two reference sites in southern Sweden during 1973-1996 are presented in this report. In order to verify the reliability of the method some investigations have been conducted at two foreign nuclear sites, Sellafield fuel reprocessing plant in England, and Pickering nuclear generating station in Canada, where the releases of {sup 14}C are known to be substantial. Furthermore, results from some measurements in the vicinity of Paldiski submarine training centre in Estonia are presented. The results of the {sup 14}C measurements of air, vegetation and annual tree rings around the two Swedish nuclear power plants show very low enhancements of {sup 14}C, if at all above the uncertainty of the measurements. Even if the accuracy of the measurements of the annual tree rings is rather good (1-2%) the contribution of {sup 14}C from the reactors to the environment is so small that it is difficult to separate it from the prevailing background levels of {sup 14}C . This is the case for all sampling procedures: in air and vegetation as well as in annual tree rings. Only on a few occasions an actual increase is observed. However, although the calculations suffer from rather large uncertainties, the calculated release rate from Barsebaeck is in fair agreement

  1. DC-Link Capacitor Voltage Regulation for Three-Phase Three-Level Inverter-Based Shunt Active Power Filter with Inverted Error Deviation Control

    Directory of Open Access Journals (Sweden)

    Yap Hoon

    2016-07-01

    Full Text Available A new control technique known as inverted error deviation (IED control is incorporated into the main DC-link capacitor voltage regulation algorithm of a three-level neutral-point diode clamped (NPC inverter-based shunt active power filter (SAPF to enhance its performance in overall DC-link voltage regulation so as to improve its harmonics mitigation performances. In the SAPF controller, DC-link capacitor voltage regulation algorithms with either the proportional-integral (PI or fuzzy logic control (FLC technique have played a significant role in maintaining a constant DC-link voltage across the DC-link capacitors. However, both techniques are mostly operated based on a direct voltage error manipulation approach which is insufficient to address the severe DC-link voltage deviation that occurs during dynamic-state conditions. As a result, the conventional algorithms perform poorly with large overshoot, undershoot, and slow response time. Therefore, the IED control technique is proposed to precisely address the DC-link voltage deviation. To validate effectiveness and feasibility of the proposed algorithm, simulation work in MATLAB-Simulink and experimental implementation utilizing a TMS320F28335 Digital Signal Processor (DSP are performed. Moreover, conventional algorithms with PI and FLC techniques are tested too for comparison purposes. Both simulation and experimental results are presented, confirming the improvement achieved by the proposed algorithm in terms of accuracy and dynamic response in comparison to the conventional algorithms.

  2. Low-power laser irradiation suppresses inflammatory response of human adipose-derived stem cells by modulating intracellular cyclic AMP level and NF-κB activity.

    Directory of Open Access Journals (Sweden)

    Jyun-Yi Wu

    Full Text Available Mesenchymal stem cell (MSC-based tissue regeneration is a promising therapeutic strategy for treating damaged tissues. However, the inflammatory microenvironment that exists at a local injury site might restrict reconstruction. Low-power laser irradiation (LPLI has been widely applied to retard the inflammatory reaction. The purpose of this study was to investigate the anti-inflammatory effect of LPLI on human adipose-derived stem cells (hADSCs in an inflammatory environment. We showed that the hADSCs expressed Toll-like Receptors (TLR 1, TLR2, TLR3, TLR4, and TLR6 and that lipopolysaccharide (LPS significantly induced the production of pro-inflammatory cytokines (Cyclooxygenase-2 (Cox-2, Interleukin-1β (IL-1β, Interleukin-6 (IL-6, and Interleukin-8 (IL-8. LPLI markedly inhibited LPS-induced, pro-inflammatory cytokine expression at an optimal dose of 8 J/cm². The inhibitory effect triggered by LPLI might occur through an increase in the intracellular level of cyclic AMP (cAMP, which acts to down-regulate nuclear factor kappa B (NF-κB transcriptional activity. These data collectively provide insight for further investigations of the potential application of anti-inflammatory treatment followed by stem cell therapy.

  3. Release of radionuclides and chelating agents from cement-solidified decontamination low-level radioactive waste collected from the Peach Bottom Atomic Power Station Unit 3

    International Nuclear Information System (INIS)

    As part of a study being performed for the Nuclear Regulatory Commission (NRC), small-scale waste-form specimens were collected during a low oxidation-state transition-metal ion (LOMI)-nitric permanganate (NP)-LOMI solidification performed in October 1989 at the Peach Bottom Atomic Power Station Unit 3. The purpose of this program was to evaluate the performance of cement-solidified decontamination waste to meet the low-level waste stability requirements defined in the NRC's ''Technical Position on Waste Form,'' Revision 1. The samples were acquired and tested because little data have been obtained on the physical stability of actual cement-solidified decontamination ion-exchange resin waste forms and on the leachability of radionuclides and chelating agents from those waste forms. The Peach Bottom waste-form specimens were subjected to compressive strength, immersion, and leach testing in accordance with the NRC's ''Technical Position on Waste Form,'' Revision 1. Results of this study indicate that the specimens withstood the compression tests (>500 psi) before and after immersion testing and leaching, and that the leachability indexes for all radionuclides, including 14C, 99 Tc, and 129I, are well above the leachability index requirement of 6.0, required by the NRC's ''Technical Position on Waste Form,'' Revision 1

  4. Co-Design Method and Wafer-Level Packaging Technique of Thin-Film Flexible Antenna and Silicon CMOS Rectifier Chips for Wireless-Powered Neural Interface Systems.

    Science.gov (United States)

    Okabe, Kenji; Jeewan, Horagodage Prabhath; Yamagiwa, Shota; Kawano, Takeshi; Ishida, Makoto; Akita, Ippei

    2015-01-01

    In this paper, a co-design method and a wafer-level packaging technique of a flexible antenna and a CMOS rectifier chip for use in a small-sized implantable system on the brain surface are proposed. The proposed co-design method optimizes the system architecture, and can help avoid the use of external matching components, resulting in the realization of a small-size system. In addition, the technique employed to assemble a silicon large-scale integration (LSI) chip on the very thin parylene film (5 μm) enables the integration of the rectifier circuits and the flexible antenna (rectenna). In the demonstration of wireless power transmission (WPT), the fabricated flexible rectenna achieved a maximum efficiency of 0.497% with a distance of 3 cm between antennas. In addition, WPT with radio waves allows a misalignment of 185% against antenna size, implying that the misalignment has a less effect on the WPT characteristics compared with electromagnetic induction. PMID:26694407

  5. Co-Design Method and Wafer-Level Packaging Technique of Thin-Film Flexible Antenna and Silicon CMOS Rectifier Chips for Wireless-Powered Neural Interface Systems

    Directory of Open Access Journals (Sweden)

    Kenji Okabe

    2015-12-01

    Full Text Available In this paper, a co-design method and a wafer-level packaging technique of a flexible antenna and a CMOS rectifier chip for use in a small-sized implantable system on the brain surface are proposed. The proposed co-design method optimizes the system architecture, and can help avoid the use of external matching components, resulting in the realization of a small-size system. In addition, the technique employed to assemble a silicon large-scale integration (LSI chip on the very thin parylene film (5 μm enables the integration of the rectifier circuits and the flexible antenna (rectenna. In the demonstration of wireless power transmission (WPT, the fabricated flexible rectenna achieved a maximum efficiency of 0.497% with a distance of 3 cm between antennas. In addition, WPT with radio waves allows a misalignment of 185% against antenna size, implying that the misalignment has a less effect on the WPT characteristics compared with electromagnetic induction.

  6. High temperature heat source generation with quasi-continuous wave semiconductor lasers at power levels of 6 W for medical use.

    Science.gov (United States)

    Fujimoto, Takahiro; Imai, Yusuke; Tei, Kazuyoku; Ito, Shinobu; Kanazawa, Hideko; Yamaguchi, Shigeru

    2014-01-01

    We investigate a technology to create a high temperature heat source on the tip surface of the glass fiber proposed for medical surgery applications. Using 4 to 6 W power level semiconductor lasers at a wavelength of 980 nm, a laser coupled fiber tip was preprocessed to contain a certain amount of titanium oxide powder with a depth of 100 μm from the tip surface so that the irradiated low laser energy could be perfectly absorbed to be transferred to thermal energy. Thus, the laser treatment can be performed without suffering from any optical characteristic of the material. A semiconductor laser was operated quasi-continuous wave mode pulse time duration of 180 ms and >95% of the laser energy was converted to thermal energy in the fiber tip. Based on two-color thermometry, by using a gated optical multichannel analyzer with a 0.25 m spectrometer in visible wavelength region, the temperature of the fiber tip was analyzed. The temperature of the heat source was measured to be in excess 3100 K. PMID:24853040

  7. Life performance of an EPR-insulated power cable exposed in service beyond 3 MGy in high-level radiation area

    Science.gov (United States)

    Grüb, R.; Langeset, B.; Maier, P.; Schönbacher, H.

    1983-09-01

    Mechanical and electrical test results are reported for a power cable that has been installed for three and a half years in a high-level radiation area at the European Organization for Nuclear Research (CERN). The degradation of selected mechanical properties as a function of absorbed dose is compared with results of a short-term irradiation in a nuclear reactor. The tensile test specimens have been taken from the ethylene propylene rubber insulation and the polyvinyl chloride sheath material of the cable after exposure in service. For the measurement of breakdown voltage, short portions of insulated cable have been used. The aim of this work was to verify that the combined functional and environmental stress factors did not lead to more damage of the cable than was expected from the value of absorbed dose, and eventually to predict more precisely the service life of similar cables. The ratios of doses after service and short-term irradiation at 50% reduction of elongation at break were about 0.5 for the insulation and 1.0 for the sheath material at a dose of about 1 MGy. However, the breakdown voltage did not show any significant variation in the dose range covered up to 3.6 MGy. Therefore, a safe lower dose limit may readily be derived from accelerated tests, but the margin until failure in service remains to be determined.

  8. Optimal Design of Stator Interior Permanent Magnet Machine with Minimized Cogging Torque for Wind Power Application

    DEFF Research Database (Denmark)

    Chen, Zhe; Zhang, Jianzhong; Cheng, Ming

    2008-01-01

    This paper proposes a new approach to minimize the cogging torque of a stator interior permanent magnet (SIPM) machine. The optimization of stator slot gap and permanent magnet is carried out and the cogging torque ripple is analyzed by using finite element analysis. Experiments on a prototype...... machine verify the theoretical analysis. A comparison between the improved SIPM generator and a radial flux permanent magnet synchronous generator for a 3-MW wind turbine is carried out. It shows that the proposed SIPM generator has the advantages of higher power density and lower cost....

  9. All-fiber high-average power nanosecond-pulsed master-oscillator power amplifier at 2  μm with mJ-level pulse energy.

    Science.gov (United States)

    Wang, Xiong; Jin, Xiaoxi; Zhou, Pu; Wang, Xiaolin; Xiao, Hu; Liu, Zejin

    2016-03-10

    We present a high-power nanosecond-pulsed Tm-doped fiber amplifier at 1.971 μm based on a master-oscillator power amplifier (MOPA) configuration. When the repetition rate is 500 kHz and the pulse width is 63.3 ns, the average power reaches 238 W, the peak power reaches 7.06 kW, and the pulse energy is 0.477 mJ. When the pulse train's repetition rate is 300 kHz with a pulse width of 63.7 ns, the average power reaches 197 W, the peak power reaches 9.73 kW, and the pulse energy is 0.66 mJ. When the pulse train's repetition rate is 200 kHz with a pulse width of 58.2 ns, the average power reaches 150 W, the peak power reaches 12.1 kW, and the pulse energy is 0.749 mJ. The spectral linewidths of the pulse trains are 0.15, 0.14, and 0.10 nm for 500 kHz repetition rate, 300 kHz repetition rate, and 200 kHz repetition rate, respectively. To the best of our knowledge, this is the first demonstration of high-power nanosecond-pulsed MOPA at 2 μm with the maximum average power reaching 238 W, the maximum peak power reaching 12.1 kW, and the maximum pulse energy reaching 0.749 mJ.

  10. 供电公司财务管理水平提升策略探讨%On the Strategies for Improving Financial Management Level of the Power Supply Company

    Institute of Scientific and Technical Information of China (English)

    时小力

    2014-01-01

    供电公司中重要的环节就是财务管理,企业经营管理和公司财务管理水平高低有着直接的关系。本文将针对供电公司财务管理水平提升策略进行探讨。%The financial management is an important link in the power company, and business management has a direct relationship with financial management level of the enterprises. This article discusses the strategies for improving financial management level of the power supply company.

  11. Improved management of SG BD demineralizer for reduced generation of low-level radioactive spent resin in Korean nuclear power plants

    International Nuclear Information System (INIS)

    Most nuclear power plants in Korea have adopted Ethanolamine(ETA) as a secondary pH control agent to increase the pH at the liquid phase, which may reduce the corrosion in steam generator tubes and moisture separator/reheat system. Along with its beneficial effect of SG protection from corrosion and degradation, the replacement of ammonia with ETA causes the increased generation of spent resin and the reduced run time of demineralizer in steam generator blowdown(SG BD) system. The composition ratio of cation- to anion- exchange resin in SG BD mixed bed should be increased in the ETA chemistry environment to meet the ratio of cation to anion in the aqueous solution, which results in the simultaneous exhaustion of cation and anion exchange resins. The utilization rate of mixed bed is greatest at the cation-to-anion ratio of 95:1 on the theoretical equivalent basis in the solution, but practically highest at that of 22:1 due to the possible inhomogeneous distribution of cation and anion exchange resins in SG BD bed. The run time of the bed could be extended by 30% such that, at that much, the purchase cost of new resin is saved and the production rate of spent resin is reduced. The guideline on the replacement of resin in SG BD bed is not necessary to secure the removal of radioactive particles without the leakage of the primary coolant into the secondary side since all the radioactive ions can be eliminated by SG BD bed with the sufficient time. They are retained during more than one month after their ingress into the SG BD bed without leakage. With the reduced replacement, thus, the SG BD spent resin that comprises 65% of low-level radioactive solid waste can be much cut down

  12. Exploring the potential impact of implementing carbon capture technologies in fossil fuel power plants on regional European water stress index levels

    NARCIS (Netherlands)

    Schakel, W.B.; Pfister, Stephan; Ramirez, C.A.

    2015-01-01

    Equipping power plants with carbon capture technology can affect cooling demand and water use. This study has explored the potential impact of large scale deployment of power plants with carbon capture technologies on future regional water stress in Europe. A database including 458 of European large

  13. Hardware Accelerated Power Estimation

    CERN Document Server

    Coburn, Joel; Raghunathan, Anand

    2011-01-01

    In this paper, we present power emulation, a novel design paradigm that utilizes hardware acceleration for the purpose of fast power estimation. Power emulation is based on the observation that the functions necessary for power estimation (power model evaluation, aggregation, etc.) can be implemented as hardware circuits. Therefore, we can enhance any given design with "power estimation hardware", map it to a prototyping platform, and exercise it with any given test stimuli to obtain power consumption estimates. Our empirical studies with industrial designs reveal that power emulation can achieve significant speedups (10X to 500X) over state-of-the-art commercial register-transfer level (RTL) power estimation tools.

  14. The isoengine: realisation of a high-efficiency power cycle based on isothermal compression

    Energy Technology Data Exchange (ETDEWEB)

    Linnemann, C.; Coney, M.W. [RWE Innogy plc, Swindon (United Kingdom)

    2005-07-01

    A novel high-efficiency internal combustion engine for power generation and direct-drive applications is being developed. Distillate-fuelled power plants in units of 7 MW electrical output are predicted to reach a net electrical efficiency of 60%. An efficiency of 58% is targeted for the gas-fired version. This compares with a net electrical efficiency of about 45% for advanced reciprocating engines of similar output but conventional design, and represents a step change in the efficiency of distributed power plant. Besides distillate oil and natural gas, the engine will be able to use suitable biofuels for efficient power generation. A 3 MW prototype engine using the full-scale engine geometry has been built to confirm the performance of the isoengine cycle. A partnership agreement has been signed by RWE Innogy and Mitsui Engineering and Shipbuilding for the future testing and development of the engine. (author)

  15. A Power Efficient Exaflop Computer Design for Global Cloud System Resolving Climate Models.

    Science.gov (United States)

    Wehner, M. F.; Oliker, L.; Shalf, J.

    2008-12-01

    Exascale computers would allow routine ensemble modeling of the global climate system at the cloud system resolving scale. Power and cost requirements of traditional architecture systems are likely to delay such capability for many years. We present an alternative route to the exascale using embedded processor technology to design a system optimized for ultra high resolution climate modeling. These power efficient processors, used in consumer electronic devices such as mobile phones, portable music players, cameras, etc., can be tailored to the specific needs of scientific computing. We project that a system capable of integrating a kilometer scale climate model a thousand times faster than real time could be designed and built in a five year time scale for US$75M with a power consumption of 3MW. This is cheaper, more power efficient and sooner than any other existing technology.

  16. 风电项目生态及电磁环境影响研究%Study of Ecological and Electromagnetic Influences on Wind Power Project

    Institute of Scientific and Technical Information of China (English)

    张承芳; 陈众

    2014-01-01

    Taking Zhaoguan 48 .3MW wind power project of Hanshan County ,Anhui province as a case stud-y ,this article evaluatesthe environmental impacts of wind power project evaluation from the ecological and e-lectromagnetic aspects ,and puts forward the prevention measures .%以安徽含山昭关48.3M W风电项目工程为例,从生态和电磁两方面探讨了风电项目的环境影响评价,并提出了相应的防治措施。

  17. A Shift of Power

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Administrative reforms are shifting prefecture government powers to the county level in an effort to boost local economies on July 8, the government of China’s southernmost Hainan Province announced that it was to hand over 177 of its administrative powers to county-level governments. The move practically dismantled the powers of the

  18. 新形势下县级供电企业人力资源管理%Human Resource Management of County-level Power Supply Enterprises under the New Situation

    Institute of Scientific and Technical Information of China (English)

    周世茹

    2013-01-01

    Under the new situation that national power grid enterprises fully completed strategic plan of "Three-Intensive Management and Five-Large Scale Development",this paper elaborated on how to improve the human resource management of county-level power supply enterprise.%在国家电网企业作出全面建成“三集五大”体系战略部署的新形势下,本文主要就县级供电企业如何提高人力资源管理水平进行阐述.

  19. Combined application of sub-toxic level of silver nanoparticles with low powers of 2450 MHz microwave radiation lead to kill Escherichia coli in a short time

    Directory of Open Access Journals (Sweden)

    Bardia Varastehmoradi

    2013-09-01

    Full Text Available   Objective(s: Electromagnetic radiations which have lethal effects on the living cells are currently also considered as a disinfective physical agent.   Materials and Methods: In this investigation, silver nanoparticles were applied to enhance the lethal action of low powers (100 and 180 W of 2450 MHZ electromagnetic radiation especially against Escherichia coli ATCC 8739. Silver nanoparticles were biologically prepared and used for next experiments. Sterile normal saline solution was prepared and supplemented by silver nanoparticles to reach the sub-inhibitory concentration (6.25 μg/mL. Such diluted silver colloid as well as free-silver nanoparticles solution was inoculated along with test microorganisms, particularly E. coli. These suspensions were separately treated by 2450 MHz electromagnetic radiation for different time intervals in a microwave oven operated at low powers (100 W and 180 W. The viable counts of bacteria before and after each radiation time were determined by colony-forming unit (CFU method. Results: Results showed that the addition of silver nanoparticles significantly decreased the required radiation time to kill vegetative forms of microorganisms. However, these nanoparticles had no combined effect with low power electromagnetic radiation when used against Bacillus subtilis spores. Conclusion: The cumulative effect of silver nanoparticles and low powers electromagnetic radiation may be useful in medical centers to reduce contamination in polluted derange and liquid wastes materials and some devices.

  20. Picosecond laser with 11 W output power at 1342 nm based on composite multiple doping level Nd:YVO4 crystal

    Science.gov (United States)

    Rodin, Aleksej M.; Grishin, Mikhail; Michailovas, Andrejus

    2016-01-01

    We report results of design and optimization of high average output power picosecond and nanosecond laser operating at 1342 nm wavelength. Developed for selective micromachining, this DPSS laser is comprised of master oscillator, regenerative amplifier and output pulse control module. Passively mode-locked by means of semiconductor saturable absorber mirror and pumped with 808 nm wavelength Nd:YVO4 master oscillator emits 12.5 ps pulses at repetition rate of 55 MHz with average output power of ∼100 mW. The four-pass confocal delay line forms a longest part of the oscillator cavity in order to suppress thermo-mechanical misalignment. Picked from the train seed pulses were injected to the cavity of regenerative amplifier based on composite Nd:YVO4 crystal with diffusion-bonded segments of multiple Nd doping concentration end-pumped at 880 nm wavelength. Laser produces pulses of ∼13 ps duration at 300 kHz repetition rate with average output power of 11 W and nearly diffraction limited beam quality of M2∼1.03. Attained high peak power ∼2.8 MW facilitates conversion to the 2nd, 3rd and 6th harmonics at 671 nm, 447 nm and 224 nm wavelengths with 80%, 50% and 15% efficiency respectively. Without seeding the regenerative amplifier transforms to electro-optically cavity-dumped Q-switched laser providing 10 ns output pulses at high repetition rates with beam propagation factor of M2∼1.06.

  1. WKA 60 wind power plant for EW Helgoland

    Energy Technology Data Exchange (ETDEWEB)

    Schwaiger, H.

    1988-01-01

    The authors demonstrate the wind power plant (0.8 to 1.3 MW range) to be built on the island of Helgoland, with its components (design and system diagrams) and a list of major technical characteristics. Details concern plant size, three-blade rotor, aerodynamically profiled rotor blades, rotor hub, rotor blade adjustment, electronic control of rotor blade drive, mechanical drive rod and turbine housing, rotor shaft and bearing, rotor brake, fixing device, spiral-toothing coupling, gear, generator shaft drive, dynamic concept and construction type of tower (50 m height, cylindrical shaft, conical base), tower basement, wind tracking system, electronics system, control and operation management, lifting and hoisting systems, assembly and maintenance concept. (HWJ).

  2. Solar thermal electric power systems with line-focus collectors. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Duff, W.S.; Karaki, S.; Shaner, W.W.; Wilbur, P.J.; Somers, E.V.; Grimble, R.E.; Wilson, H.S.; Watt, A.D.

    1978-12-01

    Electric power generation by conventional Rankine cycle heat engines with heat supplied by line-focus solar collectors was investigated. The objectives of the study were: (1) determine which of four types of line-focus solar collectors coupled with turbine-generators of conventional design has the potential to produce low-cost electric power with thermal energy in 100 to 300/sup 0/C range; (2) develop performance and cost relationships for organic Rankine cycle engines for power generation capacities from 3 MW/sub e/ to 300 MW/sub e/; (3) develop conceptual storage units for organic fluid systems. Evaluation procedures and study results and conclusion are presented and discussed in detail. (WHK)

  3. An Introduction to System-Level, Steady-State and Transient Modeling and Optimization of High-Power-Density Thermoelectric Generator Devices Made of Segmented Thermoelectric Elements

    Science.gov (United States)

    Crane, D. T.

    2011-05-01

    High-power-density, segmented, thermoelectric (TE) elements have been intimately integrated into heat exchangers, eliminating many of the loss mechanisms of conventional TE assemblies, including the ceramic electrical isolation layer. Numerical models comprising simultaneously solved, nonlinear, energy balance equations have been created to simulate these novel architectures. Both steady-state and transient models have been created in a MATLAB/Simulink environment. The models predict data from experiments in various configurations and applications over a broad range of temperature, flow, and current conditions for power produced, efficiency, and a variety of other important outputs. Using the validated models, devices and systems are optimized using advanced multiparameter optimization techniques. Devices optimized for particular steady-state operating conditions can then be dynamically simulated in a transient operating model. The transient model can simulate a variety of operating conditions including automotive and truck drive cycles.

  4. Automatic chemical monitoring in the composition of functions performed by the unit level control system in the new projects of nuclear power plant units

    Science.gov (United States)

    Denisova, L. G.; Khrennikov, N. N.

    2014-08-01

    The article presents information on the state of regulatory framework and development of a subsystem for automated chemical monitoring of water chemistries in the primary and secondary coolant circuits used as part of the automatic process control system in new projects of VVER reactor-based nuclear power plant units. For the strategy of developing and putting in use the water chemistry-related part of the automated process control system within the standard AES-2006 nuclear power plant project to be implemented, it is necessary to develop regulatory documents dealing with certain requirements imposed on automatic water chemistry monitoring systems in accordance with the requirements of federal codes and regulations in the field of using atomic energy.

  5. SEB circuit-level model in N-channel power MOSFETs; Modele pour circuits du burnout dans des MOSFETs de puissance de type N

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J.; Schrimpf, R.D.; Massengill, L.; Galloway, K.F. [Vanderbilt Univ., Nashville, TN (United States)

    1999-07-01

    A Single Event Burnout (SEB) circuit model has been developed. The dependence of SEB sensitivity on various parameters is presented and compared with experimental results. The parasitic resistance and capacitance of the device as well as the circuit parameters contribute to the length of SEB pulse. Increasing the switching frequency of the power MOSFET may be a possible way to prevent SEB in applications. (authors)

  6. PWR Power-Level Control Only With Coolant Temperature Measurement%仅基于冷却剂温度测量的压水堆功率控制

    Institute of Scientific and Technical Information of China (English)

    董哲; 黄晓津

    2015-01-01

    Power-level control is one of the key techniques which provide safe, stable and efficient operation for pressurized water reactors (PWRs), and information completeness is the basis of realizing power-level control. However, due to the fault in measurement system, it is impossible to guarantee information completeness all the time. Therefore, it is necessary study power-level control in case of information incompleteness. In this paper, by assuming the nuclear measurement system is malfunctioning, a new state-observer that can be utilized to reconstruct the nuclear power is firstly proposed. Based upon this observer, a dynamic output feedback control law is given for the power-level regulation of the PWRs. Numerical simulation shows that this newly-built controller can provide satisfactory power-level control performance.%功率控制是保证压水堆安全、稳定和高效运行的关键技术之一,而实现高性能功率控制的基础是完备的测量信息。由于在反应堆测量系统出现故障的情况下无法获取完备的测量信息,因此研究测量信息不完备情况下的反应堆功率控制问题就具有重要的工程意义。本文在核测量系统故障的前提下,提出了利用堆芯冷却剂温度测量信息来重构核功率信息的状态观测器,进而给出了保证输入状态稳定的动态输出反馈压水堆功率控制器,并通过数值仿真验证了该控制器可以提供满意的功率调节性能。

  7. Development of a kilowatt-class, joule-level ultrafast laser for driving compact high average power coherent EUV/soft x-ray sources

    Science.gov (United States)

    Reagan, Brendan A.; Baumgarten, Cory M.; Pedicone, Michael A.; Bravo, Herman; Yin, Liang; Woolston, Mark; Wang, Hanchen; Menoni, Carmen S.; Rocca, Jorge J.

    2016-03-01

    Our recent progress in the development of high energy / high average power, chirped pulse amplification laser systems based on diode-pumped, cryogenically-cooled Yb:YAG amplifiers is discussed, including the demonstration of a laser that produces 1 Joule, sub-10 picosecond duration, λ = 1.03μm pulses at 500 Hz repetition rate. This compact, all-diodepumped laser combines a mode-locked Yb:KYW oscillator and a water-cooled Yb:YAG preamplifer with two cryogenic power amplification stages to produce 1.5 Joule pulses with high beam quality which are subsequently compressed. This laser system occupies an optical table area of less than 1.5x3m2. This laser was employed to pump plasma-based soft x-ray lasers at λ = 10-20nm at repetition rates >=100 Hz. To accomplish this, temporally-shaped pulses were focused at grazing incidence into a high aspect ratio line focus using cylindrical optics on a high shot capacity rotating metal target. This results in an elongated plasma amplifier that produces microjoule pulses at several narrow-linewidth EUV wavelengths between λ = 109Å and 189Å. The resulting fraction of a milliwatt average powers are the highest reported to date for a compact, coherent source operating at these wavelengths, to the best of our knowledge.

  8. Thermal Analysis of Multi-MW Two-Level Generator Side Converters with Reduced Common-Mode-Voltage Modulation Methods for Wind Turbines

    DEFF Research Database (Denmark)

    Qin, Zian; Liserre, Marco; Blaabjerg, Frede

    2013-01-01

    Thermal performance is one of the main indicators of power converter, since it is related to both the cost of cooling system and the reliability of the power converter. Moreover, the common-mode voltage in motor driver may damage the bearing of the motor and also cause failure. Therefore, both...... the thermal performance and common-mode voltage of the converter should be taken into account during the selection process of the modulation strategies. In this paper, based on the generator side converter of a 3 MW wind power system, the common-modevoltage reduced modulation strategies are compared...... with the conventional-60o discontinuous PWM, where the common-mode voltage, power losses and thermal performance are all taken into account. In detail, the common-mode voltages are investigated both in time domain and spectrum. The power loss distribution of the power converter with the two modulation strategies...

  9. Statement by the Federal Government: Treatment of low and intermediate level radioactive wastes from nuclear power plants with regard to the irregularities disclosed in the Transnuklear GmbH

    Energy Technology Data Exchange (ETDEWEB)

    Toepfer, K.

    1988-03-02

    The Federal Government sees three major tasks to be done after inquiries have shown that irregularities disclosed in the Transnuklear business also include some relating to nuclear safety: (1) Initiate investigation of possible hazards to man or the environment, and into events and scope of events in order to provide full information. (2) Immediate consequences with regard to the treatment of low and intermediate level radioactive waste from nuclear power plant, and state supervision thereof. (3) Investigate possible consequences with regard to nuclear waste management in the FRG. The Federal Government has taken immediate action on all three levels. (orig./HSCH).

  10. Research on a Kind of Power Unit in Three-Level Circuit Test%一种三电平功率单元试验方法研究

    Institute of Scientific and Technical Information of China (English)

    周志华

    2016-01-01

    介绍了二极管中点箝位型(NPC)三电平功率单元的特点及吸收电路,分析了由于主电路漏电流的不同引起电容电压不平衡的问题,提出了一种电压均衡电路及一种适用于NPC三电平绝缘栅双极晶体管(IGBT)功率单元双脉冲测试方法,并阐述了NPC三电平功率单元双脉冲开通过程和理论依据,试验验证了该方法的正确性及可行性。%Introduction was made to the characteristics and snubbed circuits of diode neutral point clamped (NPC) three-level power unit. Analysis was made to the capacitor voltage unbalance problem caused by leakage current of main circuit. This paper proposed a kind of voltage balance circuit and a kind of suitable NPC three-level insulated-gate bipolar transistor (IGBT) power unit double pulse test method and expound-ed on the open process and theoretical basis of the NPC three-level power unit double pulse. The experimental result verifies the correctness and feasibility of this method.

  11. Recommendation of maximum allowable noise levels for offshore wind power systems; Empfehlung von Laermschutzwerten bei der Errichtung von Offshore-Windenergieanlagen (OWEA)

    Energy Technology Data Exchange (ETDEWEB)

    Werner, Stefanie [Umweltbundesamt, Dessau-Rosslau (Germany). Fachgebiet II 2.3

    2011-05-15

    When offshore wind farms are constructed, every single pile is hammered into the sediment by a hydraulic hammer. Noise levels at Horns Reef wind farm were in the range of 235 dB. The noise may cause damage to the auditory system of marine mammals. The Federal Environmental Office therefore recommends the definition of maximum permissible noise levels. Further, care should be taken that no marine mammals are found in the immediate vicinity of the construction site. (AKB)

  12. Estimation, prediction and standardization of radiation dose levels to the population in connection with nuclear power station operation in the USSR

    International Nuclear Information System (INIS)

    The report presents values of the actual gas-aerosol releases from operating nuclear power stations in the USSR. Preliminary predicted evaluations of possible gas-aerosol releases from nuclear power stations under design are also made. Taking this as a basis and using a new calculation model there has been made an evaluation of the individual and population doses from releases of this kind, with an allowance for the metabolism of radioactive aerosols in the environment. The new model makes it also possible to consider population doses from foodstuff contaminated at the region of a nuclear station and then transported to other regions. Considering the ever growing number of ionizing radiation sources and in particular that of nuclear power stations this paper raises the problem of the necessity of an international agreement on the principles of regulating the population dose and on distributing the dose limit to the population from various radiation sources used in human activity and having a world-wide significance. As a matter for discussion the following distribution pattern of the dose limit to the population (in quota) is suggested: water-cooled and water-moderated reactors - 6%, single-circuit-grand-graphite reactors - 8%, gas-cooled reactors - 3%, fast reactors - 3%, experimental reactors - 5%, thermal nuclear stations - 4%, reactors of other types - 6%, fuel-reprocessing plants - 18%, the ore, hydrometallurgy, fuel elements production - 5%, radiation chemistry, irradiators - 2%, burial grounds of liquid and solid wastes - 4%, building materials - 5%, agricultural fertilizers - 4%, accelerators, X-ray tubes, television sets -1%, reserve for other sources - 25%. It is suggested to enlarge the number of radionuclides attributed to the ''world-wide'' series considering their relatively high contribution to the population dose

  13. Voltage-Sharing Converter to Supply Single-Phase Asymmetrical Four-Level Diode-Clamped Inverter With High Power Factor Loads

    DEFF Research Database (Denmark)

    Boora, Arash A.; Nami, Alireza; Zare, Firuz;

    2010-01-01

    The output voltage quality of some of the single-phase multilevel inverters can be improved when their dc-link voltages are regulated asymmetrically. Symmetrical and asymmetrical multilevel diode-clamped inverters have the problem of dc-link capacitor voltage balancing, especially when power factor...... of the load is close to unity. In this paper, a new single-inductor multi-output dc/dc converter is proposed that can control the dc-link voltages of a single-phase diode-clamped inverter asymmetrically to achieve voltage quality enhancement. The circuit of the presented converter is explained and the main...

  14. Radiation situation and irradiation level in forest workers in places of timber works in alienation zone of Chernobyl Atomic Power Plant

    International Nuclear Information System (INIS)

    The radiation hygienic situation in the forest plots and dose load of the personnel at timber works in the alienation zone of the Chernobyl Atomic Power Plant was evaluated.It has been revealed that the density of contamination of the forest soil at the areas of timber works was 155.4-447.3 kBq centre dot m2. Maximum year equivalent dose on the lungs and total dose of external and internal irradiation in the forest workers in the zone of alienation during the work at the areas were about 40% of the values of the respective dose limits for the population of B category

  15. Design technique of ns level high-speed and large dynamic range power agility%一种ns级高速大动态功率捷变设计技术

    Institute of Scientific and Technical Information of China (English)

    何高楼

    2013-01-01

    With the increasing of electronic countermeasure,frequency-agile technique has been widely used in the field of military communication.Frequency-agile microwave signal generator is one of the most basic testing equipment,and the key technical characteristics of power agility have increasingly high requirements.Aiming at the deficiency of common ALC loop used for high speed power agility,this paper presents a design idea of high-speed and large dynamic range power agility,and realizes high speed data transmission by using the custom bus technology.The timing synchronization technologies guarantee the stability of data transmission,the calibration and compensation method of power ensure the output level excellent accuracy and achieve ns level power agility finally,which are verified by simulation and experiment.%随着电子对抗的日益加剧,捷变频技术在军事通信领域已得到广泛应用.微波捷变频信号发生器作为最基本的测试设备之一,对其关键技术特性功率捷变的要求也越来越高.针对普通ALC环路应用于高速功率捷变的不足,提出了一种高速大动态功率捷变的设计思路,并利用自定义总线技术实现了高速数据传输,时序同步技术确保了数据传输的稳定性,功率校准与补偿方法保证了优良的输出电平准确度,最终实现了ns级功率捷变,并通过仿真和实验进行了验证.

  16. 基于三电平PWM整流器的超导储能系统直接功率控制%A DIRECT POWER CONTROL METHOD FOR SUPERCONDUCTING MAGNETIC ENERGY STORAGE SYSTEM BASED ON THREE-LEVEL PWM RECTIFIER

    Institute of Scientific and Technical Information of China (English)

    王屹; 高鹏; 赵勇

    2012-01-01

    本文研究了基于三电平PWM整流器超导储能系统直接功率控制策略.分别给出了基于电压定向和虚拟磁链的直接功率控制策略的具体实现方法.根据开关表生成的原理,提出了一种新的三电平PWM整流器直接功率控制的开关表.通过Matlab/Simulink仿真分析软件建立模型,验证了本文提出的开关表的可行性,以及基于三电平PWM整流器超导储能系统直接功率控制策略良好的动静态性能.%This paper analyzed A Direct Power Control Method for Superconducting Magnetic Energy Storage (SMES) System Based on Three-level PWM reetifier. The specific realization methods for the control strategy which based on voltage directional and direct power control of virtual flux has been introduced respectively. According to the generation principle of switch table, this thesis has advanced a new kind of switch list of three-level Pulse-Width Modulation(PWM) rectifier controled by direct power. At the same time, with the aid of Matlab/Simulink software to establish the model of system, in order to verify the feasibility of new switch list and the well dynamic properties of direct power control method for SMES based on three-level PWM rectifier.

  17. FINAL REPORT – CHARACTERIZATION SURVEY OF THE SPRU LOWER LEVEL HILLSIDE AREA AT THE KNOLLS ATOMIC POWER LABORATORY, NISKAYUNA, NEW YORK DCN 5146-SR-01-0

    Energy Technology Data Exchange (ETDEWEB)

    Evan Harpenau

    2011-08-29

    The Separations Process Research Unit (SPRU) is located within the boundary of Knolls Atomic Power Laboratory (KAPL) at 2425 River Road, Niskayuna, Schenectady County, New York (Figure A-1). SPRU was designed and developed to research an efficient process to chemically separate plutonium and uranium from processed fuel. Buildings H2 and G2 were the primary research and process facilities. SPRU operated between February 1950 and October 1953 at which time the research was successful in developing useable reduction oxidation and plutonium uranium extraction processes. These processes were subsequently moved to the Hanford and the Savannah River sites for full-scale operations. Building H2 was used by KAPL after the SPRU process ceased until the late 1990s for radioactive wastewater processing and Building G2 was utilized for offices. Process areas and equipment were maintained in a safe condition under a surveillance and maintenance program.

  18. Emission of 14C by the Almirante Alvaro Alberto Nuclear Power Plant 1 and 2 and their local effects on the environmental levels

    International Nuclear Information System (INIS)

    14C is a is a long-lived beta-emitting nuclide (T1/2 = 5730 years) produced naturally in the upper atmosphere as a result of reactions between neutrons and stable 14N(14N(n,p)14C). Although in a lesser extent, nuclear power plants produce 14C as well during their routine operation. Since it is converted in 14CO2 and mixed throughout the atmosphere, it is incorporated into plant tissues, via photosynthesis process, and hence in food chain. Because of the biological importance of 14C and long half-life, it is of interest to quantify the amounts released by nuclear industry. The Brazilian nuclear central named Nuclear Central Admiral Alvaro Alberto (CNAAA) has two nuclear reactors of PWR type in operation, Angra I (657 MWe) and Angra II (1350 MWe), and one under construction, Angra III (1309 MWe PWR). The aim of this study was to determine the strength of the sources and the 14C content in the environment through analyses of air, vegetation and soils taken within 5 km (the influenced area) of CNAAA. The thesis consists of an extensive review about the subject (part one) and of four papers (part two). The first paper is about the determination of 14C concentrations released by reactors (source strength). For Angra I, a device was developed in order to sample the gaseous effluents and for Angra II, a commercial monitoring system had already been implemented since its initial operation (2001). The 14C can be emitted as hydrocarbons, CO or CO2, depending on the type of reactor. For PWRs, the main chemical form released is hydrocarbons (80 %). The monitoring system of Angra I was planned to determine both CO2 and hydrocarbon fractions but in Angra II, all hydrocarbons are converted to CO2 by using a Pd/Al2O3 catalyst at 450 deg C. The liquid scintillation was the method employed to measure the samples. The second one concerns the atmospheric dispersion of the released radiocarbon through measurements of air samples taken with 3 km from power plants, in five different wind

  19. State-of-the-art review on technology for measuring and controlling very low level radioactivity in relation to the decommissioning of nuclear power plants

    International Nuclear Information System (INIS)

    Information in relation to the measurement devices for very low radioactivity, applied in the decommissioning of electronuclear power plants, is scarce and scattered. However, some realistic information can be obtained from the specialists working on nuclear plant dismantling sites. In practice, the in situ measurements deal with two or three radionuclides only. The other containments must be determined on some samples in laboratories by means of radioanalysis and spectrometry technologies. These technologies are briefly described. One of the problems concerns the detection threshold of the measuring instruments. This threshold varies in relation with the detector efficiency, the background and the measurement duration. The application of this concept of threshold to various types of instrument is studied. Tables and graphs are given that sum up the various possibilities of detection for the usual detectors according to their effective area. The possibility of reducing the number of monitoring points using statistical methods is presented

  20. Autler-Townes splitting via frequency upconversion at ultra-low power levels in cold $^{87}$Rb atoms using an optical nanofiber

    CERN Document Server

    Kumar, Ravi; Deasy, Kieran; Chormaic, Síle Nic

    2015-01-01

    The tight confinement of the evanescent light field around the waist of an optical nanofiber makes it a suitable tool for studying nonlinear optics in atomic media. Here, we use an optical nanofiber embedded in a cloud of laser-cooled 87Rb for near-infrared frequency upconversion via a resonant two-photon process. Sub-nW powers of the two-photon beams, at 780 nm and 776 nm, co-propagate through the optical nanofiber and generation of 420 nm photons is observed. A measurement of the Autler-Townes splitting provides a direct measurement of the Rabi frequency of the 780 nm transition. Through this method, dephasings of the system can be studied. In this work, the optical nanofiber is used as an excitation and detection tool simultaneously, and it highlights some of the advantages of using fully fibered systems for nonlinear optics with atoms.

  1. AB类功率放大器输出级的计算机仿真%Class AB amplifier output power level of the computer simulation

    Institute of Scientific and Technical Information of China (English)

    周晶

    2014-01-01

    根据AB类功率放大基本电路,结合SABER软件仿真分析了交越失真产生原因、不同负载的失真以及同时说明了如何用仿真进行改善电路设计,给出了调节静态工作点和消除交越失真的方法。%According to the fundamental class AB power amplifier circuit,combined with the SABER software simulation analyses the causes in the distortion,the distortion of different load,and also explains how to use the simulation to improve the circuit design,adjust the static working point is given and the elimination of hand in the distortion of the method.

  2. Do force-time and power-time measures in a loaded jump squat differentiate between speed performance and playing level in elite and elite junior rugby union players?

    Science.gov (United States)

    Hansen, Keir T; Cronin, John B; Pickering, Stuart L; Douglas, Lee

    2011-09-01

    The purpose of this study was to investigate the discriminative ability of rebound jump squat force-time and power-time measures in differentiating speed performance and competition level in elite and elite junior rugby union players. Forty professional rugby union players performed 3 rebound jump squats with an external load of 40 kg from which a number of force-time and power-time variables were acquired and analyzed. Additionally, players performed 3 sprints over 30 m with timing gates at 5, 10, and 30 m. Significant differences (p rugby union players; however, a number of force and power variables including peak force, PP, force at 100 milliseconds from minimum force, and force and impulse 200 milliseconds from minimum force were significantly (p rugby union players. For speed development in rugby union players, training strategies should aim to optimize the athlete's power to weight ratio, and lower body resistance training should focus on movement velocity. For player development to transition elite junior players to elite status, adding lean mass is likely to be most beneficial.

  3. Nuclear power plant with new-generation WWER-1000 units

    International Nuclear Information System (INIS)

    The Czechoslovak nuclear industry is faced with a serious problem posed by the growing capital demands of nuclear power plants. Comparison with a number of foreign nuclear power plants revealed that the basic units of the Czechoslovak nuclear programme, WWER-1000 plants of the Zaporozhe type, have reserves in their technical design that can be utilized to reduce the capital and operating costs. This is the object of design work on a new-generation WWER-1000 type unit. The goals of the project, its organization and the extent of participation of the Czechoslovak party are described. The main target parameters of the new-generation unit (NGU) per gross output of a 1000 MWe unit, as compared with the Temelin nuclear power plant units, are as follows: concrete consumption (m3/MW) NGU/Temelin: 200/406; physical lifetime of the nuclear power plant (years): 50/30; possibility of power control: daily/weekend; area permanently occupied by the facility including cooling towers (m2/MW): 220/358; area temporarily occupied (m2/MW): 136/385; specific capital costs (CSK/MWh) 180/226. (Z.S.)

  4. Checking Power:An Argument from the Point of View of Utilitarianism-The Analysis of County-levelPower Lists”%控制权力:一个功利主义视角--县政“权力清单”辨析

    Institute of Scientific and Technical Information of China (English)

    周庆智

    2014-01-01

    目前我国县级政府推行“权力清单”的目的是要控制和规范政府的行政权力,目标是适应市场经济发展和社会多样性变化而控制和约束权力的越界和不当行为,从而把政府与市场、政府与社会的关系确立在法治基础之上。“权力清单”的规范涉及中央与地方分权、政府职能转变、治理法治化等问题。然而,控制和规范政府权力,不仅涉及权力的结构性问题,更涉及权力的本质规定问题。县政“权力清单”的出台是在不触动基本权力结构的前提下做出的,也就是说,“权力清单”只是政府功能性权力的范围和职责的调整。规范县政权力必须在基本政治框架内和权力结构上做出制度性的调整和结构性的调适,不然,“权力清单制度”的推展不可能达到控制和规范政府行政权力的目标,只能是政府“自己规范自己权力”的单方面举措而已。%The purpose of carrying out “power lists”policy is to control and standardize the administration power of government so that the transgressing and improper behaviors of government can be placed under control and checked with development of market economy and diversification of society.The essence of all of that is to base the relationship between government and market,between government and society on the foundation of rule of law.Standardizing“power lists”involves the issues of separating power between central government and local government,functional transition of government,and the process of rule of law.However,not only does con-trolling and standardizing power involve the problem of power structure,but also involves the essential standard of power.The precondition of county-levelpower lists”is intended not to touch the basic power structure.In other words,“power lists”is j ust adj usting scope and duty of functional power of government,and standardizing county-level government

  5. Repeatable, accurate, and high speed multi-level programming of memristor 1T1R arrays for power efficient analog computing applications

    Science.gov (United States)

    Merced-Grafals, Emmanuelle J.; Dávila, Noraica; Ge, Ning; Williams, R. Stanley; Strachan, John Paul

    2016-09-01

    Beyond use as high density non-volatile memories, memristors have potential as synaptic components of neuromorphic systems. We investigated the suitability of tantalum oxide (TaOx) transistor-memristor (1T1R) arrays for such applications, particularly the ability to accurately, repeatedly, and rapidly reach arbitrary conductance states. Programming is performed by applying an adaptive pulsed algorithm that utilizes the transistor gate voltage to control the SET switching operation and increase programming speed of the 1T1R cells. We show the capability of programming 64 conductance levels with algorithm is also utilized to program 16 conductance levels on a population of cells in the 1T1R array showing robustness to cell-to-cell variability. In general, the proposed algorithm results in approximately 10× improvement in programming speed over standard algorithms that do not use the transistor gate to control memristor switching. In addition, after only two programming pulses (an initialization pulse followed by a programming pulse), the resulting conductance values are within 12% of the target values in all cases. Finally, endurance of more than 106 cycles is shown through open-loop (single pulses) programming across multiple conductance levels using the optimized gate voltage of the transistor. These results are relevant for applications that require high speed, accurate, and repeatable programming of the cells such as in neural networks and analog data processing.

  6. Repeatable, accurate, and high speed multi-level programming of memristor 1T1R arrays for power efficient analog computing applications

    Science.gov (United States)

    Merced-Grafals, Emmanuelle J.; Dávila, Noraica; Ge, Ning; Williams, R. Stanley; Strachan, John Paul

    2016-09-01

    Beyond use as high density non-volatile memories, memristors have potential as synaptic components of neuromorphic systems. We investigated the suitability of tantalum oxide (TaOx) transistor-memristor (1T1R) arrays for such applications, particularly the ability to accurately, repeatedly, and rapidly reach arbitrary conductance states. Programming is performed by applying an adaptive pulsed algorithm that utilizes the transistor gate voltage to control the SET switching operation and increase programming speed of the 1T1R cells. We show the capability of programming 64 conductance levels with programming speed and programming error. The algorithm is also utilized to program 16 conductance levels on a population of cells in the 1T1R array showing robustness to cell-to-cell variability. In general, the proposed algorithm results in approximately 10× improvement in programming speed over standard algorithms that do not use the transistor gate to control memristor switching. In addition, after only two programming pulses (an initialization pulse followed by a programming pulse), the resulting conductance values are within 12% of the target values in all cases. Finally, endurance of more than 106 cycles is shown through open-loop (single pulses) programming across multiple conductance levels using the optimized gate voltage of the transistor. These results are relevant for applications that require high speed, accurate, and repeatable programming of the cells such as in neural networks and analog data processing.

  7. Repeatable, accurate, and high speed multi-level programming of memristor 1T1R arrays for power efficient analog computing applications.

    Science.gov (United States)

    Merced-Grafals, Emmanuelle J; Dávila, Noraica; Ge, Ning; Williams, R Stanley; Strachan, John Paul

    2016-09-01

    Beyond use as high density non-volatile memories, memristors have potential as synaptic components of neuromorphic systems. We investigated the suitability of tantalum oxide (TaOx) transistor-memristor (1T1R) arrays for such applications, particularly the ability to accurately, repeatedly, and rapidly reach arbitrary conductance states. Programming is performed by applying an adaptive pulsed algorithm that utilizes the transistor gate voltage to control the SET switching operation and increase programming speed of the 1T1R cells. We show the capability of programming 64 conductance levels with programming speed and programming error. The algorithm is also utilized to program 16 conductance levels on a population of cells in the 1T1R array showing robustness to cell-to-cell variability. In general, the proposed algorithm results in approximately 10× improvement in programming speed over standard algorithms that do not use the transistor gate to control memristor switching. In addition, after only two programming pulses (an initialization pulse followed by a programming pulse), the resulting conductance values are within 12% of the target values in all cases. Finally, endurance of more than 10(6) cycles is shown through open-loop (single pulses) programming across multiple conductance levels using the optimized gate voltage of the transistor. These results are relevant for applications that require high speed, accurate, and repeatable programming of the cells such as in neural networks and analog data processing.

  8. The Definition of the Village-level Public Power under the Background of the Vil lagers′ Self-governance%村民自治背景下的村级公共权力厘定

    Institute of Scientific and Technical Information of China (English)

    郝炜

    2012-01-01

    村民自治背景下,基层社会治理发生了重大转变,以村级公共权力为视角进行观察,能够比较准确地反映这种转变。基于对制度文本及实践模式的研究,村级公共权力的基本内涵可以确定为,在中国共产党领导下的村级政治主体为实现村级公共利益进行民主选举、民主决策、民主管理、民主监督的法定权力。在这一基本内涵的基础上可以发现,村级公共权力的静态回路是一个多主体多层次的复杂体系,且其运行过程存在不同环节的发展不均衡和结果低效率的现象。%Under the background of villagers′ self-governance,grass-root society manageme nt has greatly changed.These changes can be accurately observed from the view o f the village-level public power.The village-level public power,based on the s tudy of the system text and practice mode,can be defined as the legal power of the political subjects at village-level in achieving their public interests unde r the leadership of the Chinese Communist Party,by way of democratic elections,democratic decision-making,democratic management and supervision.And on this basis the static structure of the village-level public power turns out to be a complex system of multi-level and multi-subject,unavoid of the phenomena of une ven development at different steps and low efficiency of results in its operatio n.

  9. Review and Analysis of Solid Long-lived and High Level Radioactive Waste arising at the Chernobyl Nuclear Power Plant and the Restricted Zone

    International Nuclear Information System (INIS)

    The study characterised potential waste arisings in the Exclusion Zone surrounding the Chernobyl Nuclear Power Plant. Studied sites include the Industrial Zone outside the Sarcophagus, three engineered disposal sites (the so-called PZRO), non-engineered near surface trench dumps (PVLRO), contaminated soil and sites of ''unauthorized'' disposal within the Exclusion Zone. Analysis of the previous methodology used for waste characterisation and inventory estimates identified a number of errors. A new database was established, which contains the most up-to date information on radwaste in the Exclusion Zone. Based on the analysis of the available information and potential radiological consequences, a judgement was taken regarding the priority of waste retrieval. In a number of cases it is necessary to carry out risk assessment to ensure that in-situ disposal would satisfy the Ukrainian regulations. Assessments of waste stream volumes for subsequent incineration, encapsulation, storage and disposal in the planned near-surface facilities have been made. It is judged that throughput and capacity of the planned waste management facilities specified by OSAT is, in general, appropriate to the likely waste arisings. (author)

  10. Sound Power Measurement

    OpenAIRE

    Ocepek , Primož

    2015-01-01

    In process of making and testing new products it has become quite important how much noise product is producing. Trends dictates that new products must be more powerful better but producing less sound than other products. The trends made knowledge about acoustics and sound power level recommended. In making of household appliances is knowledge even mandatory. Thesis introduces all knowledges necessary for understanding sound power level. First we introduce what is sound and from which sou...

  11. The radiological impact associated with the options available for the transportation of Intermediate Level Wastes with respect to a Minimum Power Scenario

    International Nuclear Information System (INIS)

    The radiological impact of the options available for the transportation of ILW has been assessed. The radiation exposure from normal transport operations was estimated assuming that all ILW transport containers emit the maximum radiation levels specified in the IAEA Transport Regulations. Regardless of whether road or rail will be used to convey the ILW, the radiation doses to the public are very low. The collective dose to transport personnel has also been found to be low. However, the cautious assumptions adopted in this study indicate that certain individuals could theoretically receive significant doses. The practical significance of these doses will be determined by actual work patterns and the actual levels of radiation penetrating the ILW transport containers. The radiological consequences that might result from a notional release of radioactive material from an ILW transport container conveying Magnox silo sludges through an urban area were evaluated. No consideration was given to the precursors of the release nor to the frequency with which this release might occur. The results suggest that for a 10-6 fractional release, the radiological consequences will be extremely small. In judging these results due account must be taken of the frequency with which such releases may be predicted to occur. (author)

  12. Economic feasibility of hydrogen enrichment for reducing NOx emissions from landfill gas power generation alternatives: A comparison of the levelized cost of electricity with present strategies

    International Nuclear Information System (INIS)

    Based on recent research showing that hydrogen enrichment can lower NOx emissions from landfill gas combustion below future NOx emission control standards imposed by both federal and California state regulations, an investigation was performed to compare the levelized cost of electricity of this technology with other options. In this cost study, a lean-burn reciprocating engine with no after-treatment was the baseline case to compare six other landfill gas-to-energy projects. These cases include a lean burn engine with selective catalytic reduction after treatment, a lean-burn microturbine, and four variations on an ultra-lean-burn engine utilizing hydrogen enrichment with each case using a different method of hydrogen production. Only hydrogen enrichment with an in-stream autothermal fuel reformer was shown to be potentially cost-competitive with current strategies for reaching the NOx reduction target in IC engines. - Highlights: ► Levelized cost of electricity for hydrogen enriched combustion was compared. ► Various ultra-lean-burn engines and microturbines with hydrogen were analyzed. ► Combustion with an autothermal fuel reformer was potentially cost-competitive.

  13. Power electronics for low power arcjets

    Science.gov (United States)

    Hamley, John A.; Hill, Gerald M.

    1991-01-01

    In anticipation of the needs of future light-weight, low-power spacecraft, arcjet power electronics in the 100 to 400 W operating range were developed. Limited spacecraft power and thermal control capacity of these small spacecraft emphasized the need for high efficiency. Power topologies similar to those in the higher 2 kW and 5 to 30 kW power range were implemented, including a four transistor bridge switching circuit, current mode pulse-width modulated control, and an output current averaging inductor with an integral pulse generation winding. Reduction of switching transients was accomplished using a low inductance power distribution network, and no passive snubber circuits were necessary for power switch protection. Phase shift control of the power bridge was accomplished using an improved pulse width modulation to phase shift converter circuit. These features, along with conservative magnetics designs allowed power conversion efficiencies of greater than 92.5 percent to be achieved into resistive loads over the entire operating range of the converter. Electromagnetic compatibility requirements were not considered in this work, and control power for the converter was derived from AC mains. Addition of input filters and control power converters would result in an efficiency of on the order of 90 percent for a flight unit. Due to the developmental nature of arcjet systems at this power level, the exact nature of the thruster/power processor interface was not quantified. Output regulation and current ripple requirements of 1 and 20 percent respectively, as well as starting techniques, were derived from the characteristics of the 2 kW system but an open circuit voltage in excess of 175 V was specified. Arcjet integration tests were performed, resulting in successful starts and stable arcjet operation at power levels as low as 240 W with simulated hydrazine propellants.

  14. 考虑水位影响的蒸汽动力发电机组给水加热器变工况特性%Varying Condition Characteristic of Feedwater Heater Considering Liquid Level in Steam Power Generating Unit

    Institute of Scientific and Technical Information of China (English)

    杨涛; 胥建群; 周克毅; 石永锋

    2014-01-01

    基于量纲分析建立三段式加热器变工况数学模型,并将其结合疏水混入蒸汽后疏冷段传热系数的变化建立加热器低水位运行特性模型;以某330 MW机组#1高压加热器为例,应用模型分别计算正常水位变工况运行端差、低水位运行疏冷段换热系数及端差特性;将计算结果与试验数据对比验证,定量分析了加热器端差随水位及负荷的变化规律,并重新设定安全水位和经济水位。为了解加热器低水位运行特性,实现对水位的及时调整提供参考。%A mathematical model of three-section heater for varying condition was established based on dimensional analysis. The operation characteristic of low liquid level was modelled with the calculation of heat transfer coefficient of drain cooler mixed with steam. Taking #1 high pressure feedwater heater of a 330 MW steam turbine for example, the model was used to calculate the terminal temperature difference of regular liquid level, the heat transfer condition of drain cooler and the terminal temperature difference of low liquid level. The calculation results were verified by the experimental data. The influence of liquid level and power load on terminal temperature difference was also quantitativly analyzed, and the security level and economic level were reseted. The research provides a reference for analyzing the operation characteristic of low liquid level and adjusting liquid level timely.

  15. [Analysis of the connection between the level of protein fractions and immunoglobulins in blood serum with irradiation in nuclear power enterprise workers].

    Science.gov (United States)

    Tel'nov, V I

    1996-01-01

    989 workers of atomic industry at the age from 35 to 78 years old subjected to the general external gamma radiation and incorporation of plutonium 239 in a wide range of doses about 17-40 years ago have been examined for the protein indices with the radiation effect bearing in mind nine non-radiation factors. The step-by-step regression analysis revealed a positive linear link for the total protein level, absolute content of alpha-I-globulins with the total dose of external gamma radiation. Increasing of serum proteins entropy, correlated with external radiation by protein shifts effect, had not coincided with its age increasing. The influence of plutonium-239 incorporation on the examined protein parameters was not found. PMID:9254521

  16. Reducing Dynamic Power and Leakage Power for Embedded Systems

    OpenAIRE

    Yasuura, Hiroto

    2002-01-01

    This paper presents a system-level technique for embedded processor-based systems targeting both dynamic power and leakage power reduction using datapath width optimization. By means of tuning the design parameter, datapath width tailored to a given application requirements, the processors and memories are optimized resulting in significant power reduction, not only for dynamic power but also for leakage power. In our experiments for several real embedded applications, power reduction without...

  17. 强馈入弱开机方式下上海电网电能绿色管理实践与研究%Practice and Research of Electric Energy Green Management in Shanghai Power Grid Under High-Level Power Import and Scale-Reduced Online Mode

    Institute of Scientific and Technical Information of China (English)

    杨凌辉; 陈洪岗; 李福兴; 徐琴; 吕敬友

    2016-01-01

    随着全国范围内大面积雾霾的频发,国务院制定《《大气污染防治行动计划》,“史上最严环保法”和排放标准实施,能源局制定《煤电节能减排升级与改造行动计划(2014-2020)》,能源结构转型与能源消费方式转变已上升至国家战略。国网上海电科院根据国网公司总体规划和上海市能源发展要求,从电网、电源和网源协调等三个方面开展面向大规模清洁能源消纳的“强馈入弱开机”方式下电网电能绿色管理实践研究,进一步优化本地机组运行方式,建立上海地区火电机组绿色评价体系,畅通电源至电网的能源输送通道,引领上海电网绿色转型,有力推动上海能源结构和能源消费模式新一轮“绿色”升级。%With frequent occurrence of a large scale haze weather in nationwide area, the State Council draws up , which is one of the most stringent environmental protection law and emission standards implementation. Energy bureau draws up , which means energy restructure and energy consumption patterns have integrated into the national strategies. State grid shanghai electric power science research institute is based on overall planning of state grid and Shanghai energy development requirements, it carries out power grid green management practice and research under large scale clean energy consumptive‘high-level power import and scale-reduced online’ mode from state grid network, electric power and network resource coordination. State grid shanghai electric power science research institute optimizes local units operation mode further and establishes green evaluation system for thermal power units in Shanghai area, makes transmission channel easy for power resources to power grid network, leads green transformation of Shanghai power grid and strongly promotes new round green update of Shanghai energy structure and energy consumption patterns.

  18. Avian radioecology on a nuclear power station site. Final report. Occurrence and effects of chronic, low-level oil contamination in a population of sooty terns (Sterna fuscata)

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, M.J.

    1978-07-05

    Records from 45,219 Sooty Terns (Sterna fuscata) captured for banding and examined for presence of oil on plumage were assessed for occurrence and effects of chronic, low-level oil contamination. Occurrence of oiled plumage averaged 2.6% for all years between 1962 and 1977, and ranged from 0.2% to 12.0% within years. Incidence of oiling increased significantly from the 1960's to the 1970's, and was far higher in 1970 than any other year. Oil was most frequently found on posterior, ventral plumage suggesting contact is made when Sooty Terns dip to the sea surface when foraging. A paired comparison shows that return rates were not significantly different between birds with and without detectable oil on plumage. Weights of oiled birds did not differ from controls, and no demonstrable effect of oiling on nesting was found. Sooty Terns are less susceptible to oil pollution than most other seabirds. Food is caught at or above the surface by contact dipping, and landing on the water is rare. (The report contains nothing about radioecology).

  19. 低功耗两线制电容式液位变送器的研制%Development of a Low-Power Two-Wire Capacitive Liquid Level Transmitter

    Institute of Scientific and Technical Information of China (English)

    陈海侠; 高宗海; 申阿维; 赖化凤

    2011-01-01

    With an aim at overcoming the disadvantages of high output impedance, poor load capacity and signal process difficulties caused by the small capacitance of capacitive liquid level transmitter, a low-power two-line capacitive liquid level transmitter based on microcontroller MSP430 is designed. The comparator and D/A converter inside the low-power 16-bit microcontroller MSP430 are rationally used to convert the output signal into 4-20 mA current transmitted by a two-wire way. The whole system adopts low-power chips so as to ensure that the transmitter can work properly with the static current less than 4 mA. Driven cable technology is also used effectively to shield the interference caused by distributed capacitance brought about by the measuring circuit and the cable. The results show that the transmitter can achieve a precision for liquid level measurement of 6‰ within 700 mm and that the whole system can realize two-wire system with low-power consumption, stability and reliability.%针对电容式液位传感器电容量较小引起的输出阻抗高、负载能力差、信号处理困难的缺点,基于电容充放电原理电路实现微电容测量,进而设计了基于MSP430单片机的两线制电容式液位变送器.合理利用了超低功耗的16位单片机MSP430内部的比较器、计数器和D/A转换器,输出信号经V/I电路转换为4~ 20 mA电流,两线制变送输出.整个系统全部选用低功耗芯片,以保证变送器静态工作电流低于4mA.采用驱动电缆技术,有效屏蔽测量电路及电缆带来的分布电容的干扰.试验结果表明,在0 ~700 mm范围内,液位变送器的测量精度可以达到6‰.系统可实现两线制,且功耗低,稳定可靠.

  20. 县级供电企业业务扩充管理优化策略%Business expansion management optimization strategy at the county level power supply enterprises

    Institute of Scientific and Technical Information of China (English)

    周文伟

    2013-01-01

    The article analyzed the working process of busi-ness expansion management at county power supply enterprise at present. In order to shorten the customer connect cable with time and improve customer satisfaction, the short board optimization is made. Plane collaboration mechanism at county company level and point-to-point sunshine business expansion management system at power substation level is established. Finally it realized the eco-nomic and social benefits of the steady climb and electricity“gov-ernment trust, customer satisfaction”.%通过对目前县级供电企业业扩工作流程的分析,以缩短客户接电报装时限、提升客户满意度为目标,打造县公司层面的平面协作机制和供电所层面的点对点的阳光业扩管理体系,最终实现售电量稳步攀升和“政府放心,客户满意”的经济、社会效益的双丰收。

  1. 新疆部分燃煤和电厂粉煤灰中天然放射性水平分析%The Natural Radioactive Level of the Coal, Coal Cinder and Slag from Power Plants

    Institute of Scientific and Technical Information of China (English)

    谢贵英; 艾尔肯·阿不列木; 艾克拜尔·吐合提

    2011-01-01

    采用低本底γ能谱仪对乌鲁木齐、伊犁和哈密地区的煤以及华电厂和国电厂的粉煤灰中的天然放射性核素含量进行了测量.测量结果:226Ra、232Th、40K含量按样品个数的加权平均值,乌鲁木齐煤为5.54、3.51、69.15 Bq/kg;伊犁煤为9.59、4.02、72.95 Bq/kg;哈密煤为7.42、4.87、88.32 Bq/kg;华电厂粉煤灰中为29.31、15.57、111.39 Bq/kg;国电厂粉煤灰中为24.67、16.22、133.98 Bq/kg.并依据国家标准对粉煤灰进行分类,结果表明,粉煤灰的使用不受限制.%The - ray spectrometer was used to analyze the natural radioactive level of the coal from Urumqi, Yi li and Ha mi areas; coal cinder and slag from China power plant and state power plant in Urumqi. The average value of ,,and of coal is 5. 54、 3. 51、69. 15 from Urumqi; 9. 59、4. 02,72. 95from Yi li;7. 42、4. 87、88. 32from Ha mi;the coal cinder is 29. 31、15. 57、111. 39 from China power plant; 24. 67、16. 22、133. 98 from state power plant, respectively. The result reveals that the coal cinder' s application range has no limit according to national standard.

  2. A Bayesian framework to account for complex non-genetic factors in gene expression levels greatly increases power in eQTL studies.

    Directory of Open Access Journals (Sweden)

    Oliver Stegle

    2010-05-01

    Full Text Available Gene expression measurements are influenced by a wide range of factors, such as the state of the cell, experimental conditions and variants in the sequence of regulatory regions. To understand the effect of a variable of interest, such as the genotype of a locus, it is important to account for variation that is due to confounding causes. Here, we present VBQTL, a probabilistic approach for mapping expression quantitative trait loci (eQTLs that jointly models contributions from genotype as well as known and hidden confounding factors. VBQTL is implemented within an efficient and flexible inference framework, making it fast and tractable on large-scale problems. We compare the performance of VBQTL with alternative methods for dealing with confounding variability on eQTL mapping datasets from simulations, yeast, mouse, and human. Employing Bayesian complexity control and joint modelling is shown to result in more precise estimates of the contribution of different confounding factors resulting in additional associations to measured transcript levels compared to alternative approaches. We present a threefold larger collection of cis eQTLs than previously found in a whole-genome eQTL scan of an outbred human population. Altogether, 27% of the tested probes show a significant genetic association in cis, and we validate that the additional eQTLs are likely to be real by replicating them in different sets of individuals. Our method is the next step in the analysis of high-dimensional phenotype data, and its application has revealed insights into genetic regulation of gene expression by demonstrating more abundant cis-acting eQTLs in human than previously shown. Our software is freely available online at http://www.sanger.ac.uk/resources/software/peer/.

  3. The 8.4 MW Modulator/Regulator Power Systems for the Electron Cyclotron Heating Facility Upgrade at DIII-D

    Energy Technology Data Exchange (ETDEWEB)

    S.G.E. Pronko; D.S. Baggest

    1999-12-01

    Over the next three years the DIII-D National Fusion Facility at General Atomics will upgrade its electron cyclotron heating (ECH) capability from the present 3 MW at 110 GHz to 10 MW of injected microwave power. There will be ten gyrotron tubes supplied by five 8.4 MW modulator/regulator (M/R) power systems. The project has gained considerable leverage from the acquisition of surplus hardware from the MFTF program that was conducted at LLNL in the early 1980s. One of these systems had been refurbished and converted for use as an ECH power supply earlier. The experience gained and the lessons learned from operating that system have proved valuable in guiding the engineering of the new systems. This paper provides an overview of the power system design and a report on the present status of the project.

  4. Thermal Hydraulic Analysis of 3 MW TRIGA Research Reactor of Bangladesh Considering Different Cycles of Burnup

    Directory of Open Access Journals (Sweden)

    M.H. Altaf

    2014-12-01

    Full Text Available Burnup dependent steady state thermal hydraulic analysis of TRIGA Mark-II research reactor has been carried out utilizing coupled point kinetics, neutronics and thermal hydraulics code EUREKA-2/RR. From the previous calculations of neutronics parameters including percentage burnup of individual fuel elements performed so far for 700 MWD burnt core of TRIGA reactor showed that the fuel rod predicted as hottest at the beginning of cycle (fresh core was found to remain as the hottest until 200 MWD of burn, but, with the progress of core burn, the hottest rod was found to be shifted and another rod in the core became the hottest. The present study intends to evaluate the thermal hydraulic parameters of these hottest fuel rods at different cycles of burnup, from beginning to 700 MWD core burnt considering reactor operates under steady state condition. Peak fuel centerline temperature, maximum cladding and coolant temperatures of the hottest channels were calculated. It revealed that maximum temperature reported for fuel clad and fuel centerline found to lie below their melting points which indicate that there is no chance of burnout on the fuel cladding surface and no blister in the fuel meat throughout the considered cycles of core burnt.

  5. Thermal Hydraulic Analysis of 3 MW TRIGA Research Reactor of Bangladesh Considering Different Cycles of Burnup

    OpenAIRE

    M. H. Altaf; Badrun, N. H.

    2014-01-01

    Burnup dependent steady state thermal hydraulic analysis of TRIGA Mark-II research reactor has been carried out utilizing coupled point kinetics, neutronics and thermal hydraulics code EUREKA-2/RR. From the previous calculations of neutronics parameters including percentage burnup of individual fuel elements performed so far for 700 MWD burnt core of TRIGA reactor showed that the fuel rod predicted as hottest at the beginning of cycle (fresh core) was found to remain as the hottest until 200 ...

  6. Thermal hydraulic analysis of 3 MW TRIGA research reactor of bangladesh considering different cycles of burnup

    International Nuclear Information System (INIS)

    Burnup dependent steady state thermal hydraulic analysis of TRIGA Mark-II research reactor has been carried out utilizing coupled point kinetics, neutronics and thermal hydraulics code EUREKA-2/RR. From the previous calculations of neutronics parameters including percentage burnup of individual fuel elements performed so far for 700 MWD burnt core of TRIGA reactor showed that the fuel rod predicted as hottest at the beginning of cycle (fresh core) was found to remain as the hottest until 200 MWD of burn, but, with the progress of core burn, the hottest rod was found to be shifted and another rod in the core became the hottest. The present study intends to evaluate the thermal hydraulic parameters of these hottest fuel rods at different cycles of burnup, from beginning to 700 MWD core burnt considering reactor operates under steady state condition. Peak fuel centerline temperature, maximum cladding and coolant temperatures of the hottest channels were calculated. It revealed that maximum temperature reported for fuel clad and fuel centerline found to lie below their melting points which indicate that there is no chance of burnout on the fuel cladding surface and no blister in the fuel meat throughout the considered cycles of core burnt. (author)

  7. Influence of System Inertia Time Constants on Transient Stability Level of Interconnected AC Power Grid%系统惯性时间常数对互联电网暂态稳定水平的影响

    Institute of Scientific and Technical Information of China (English)

    赵振元; 陈维荣; 戴朝华; 张雪霞

    2012-01-01

    由于区域电网的互联,整个系统的惯性时间常数将会发生明显变化,继而会影响整网的暂态稳定水平。基于暂态能量函数法,通过对等值2机系统进行数学推导并作暂态稳定分析,研究了系统在各种运行方式下,2端机组惯量变化对电力系统暂态稳定水平产生的影响,比较了两端机组惯量变化分别对系统暂态稳定性的影响,并发现了系统机组惯性时间常数对系统暂态稳定水平造成的影响与系统的负荷水平及初始工况有关。在理论分析的基础上,结合相关算例在各种运行方式下进行了仿真研究,仿真结果验证了分析结果的正确性。%Due to the interconnection of regional power grids, the inertia time constant of the whole interconnected grid evidently changes, then transient stability level of the interconnected power grid will be influenced. Based on transient energy function, by means of mathematical deduce for equivalent two-machine system and analysis on its transient stability, the influences of unit inertial changes at both terminals on transient stability level of the whole system under various operation modes are researched, and respective influences of terminal unit inertial changes on transient stability of the whole grid are compared, besides, it is found that the influences of unit inertial time constants on system transient stability level are relevant to load level and initial operating condition of the power grid. Based on theoretical analysis, simulation of concerned examples under various operation modes is performed and the correctness of theoretical analysis results is verified by simulation results.

  8. High field NMR spectroscopy and FTICR mass spectrometry: powerful discovery tools for the molecular level characterization of marine dissolved organic matter from the South Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    N. Hertkorn

    2012-01-01

    Full Text Available Non target high resolution organic structural spectroscopy of marine dissolved organic matter (DOM isolated on 27 November 2008 by means of solid phase extraction (SPE from four different depths in the South Atlantic Ocean off the Angola coast (3.1° E; −17.7° S; Angola basin provided molecular level information of complex unknowns with unprecedented coverage and resolution. The sampling was intended to represent major characteristic oceanic regimes of general significance: 5 m (FISH; near surface photic zone, 48 m (FMAX; fluorescence maximum, 200 m (upper mesopelagic zone and 5446 m (30 m above ground.

    800 MHz proton (1H nuclear magnetic resonance (NMR 1H NMR, spectra were least affected by fast and differential transverse NMR relaxation and produced at first similar looking, rather smooth bulk NMR envelopes reflecting intrinsic averaging from massive signal overlap. Visibly resolved NMR signatures were most abundant in surface DOM but contributed at most a few percent to the total 1H NMR integral and were mainly limited to unsaturated and singly oxygenated carbon chemical environments. The relative abundance and variance of resolved signatures between samples was maximal in the aromatic region; in particular, the aromatic resolved NMR signature of the deep ocean sample at 5446 m was considerably different from that of all other samples. When scaled to equal total NMR integral, 1H NMR spectra of the four marine DOM samples revealed considerable variance in abundance for all major chemical environments across the entire range of chemical shift. Abundance of singly oxygenated CH units and acetate derivatives declined from surface to depth whereas aliphatics and carboxyl-rich alicyclic molecules (CRAM derived molecules increased in abundance. Surface DOM contained a remarkably lesser abundance of methyl esters than all other marine DOM, likely a consequence of photodegradation from direct

  9. High-field NMR spectroscopy and FTICR mass spectrometry: powerful discovery tools for the molecular level characterization of marine dissolved organic matter

    Directory of Open Access Journals (Sweden)

    N. Hertkorn

    2013-03-01

    Full Text Available High-performance, non-target, high-resolution organic structural spectroscopy was applied to solid phase extracted marine dissolved organic matter (SPE-DOM isolated from four different depths in the open South Atlantic Ocean off the Angola coast (3° E, 18° S; Angola Basin and provided molecular level information with extraordinary coverage and resolution. Sampling was performed at depths of 5 m (Angola Current; near-surface photic zone, 48 m (Angola Current; fluorescence maximum, 200 m (still above Antarctic Intermediate Water, AAIW; upper mesopelagic zone and 5446 m (North Atlantic Deep Water, NADW; abyssopelagic, ~30 m above seafloor and produced SPE-DOM with near 40% carbon yield and beneficial nuclear magnetic resonance (NMR relaxation properties, a crucial prerequisite for the acquisition of NMR spectra with excellent resolution. 1H and 13C NMR spectra of all four marine SPE-DOM showed smooth bulk envelopes, reflecting intrinsic averaging from massive signal overlap, with a few percent of visibly resolved signatures and variable abundances for all major chemical environments. The abundance of singly oxygenated aliphatics and acetate derivatives in 1H NMR spectra declined from surface to deep marine SPE-DOM, whereas C-based aliphatics and carboxyl-rich alicyclic molecules (CRAM increased in abundance. Surface SPE-DOM contained fewer methyl esters than all other samples, likely a consequence of direct exposure to sunlight. Integration of 13C NMR spectra revealed continual increase of carboxylic acids and ketones from surface to depth, reflecting a progressive oxygenation, with concomitant decline of carbohydrate-related substructures. Aliphatic branching increased with depth, whereas the fraction of oxygenated aliphatics declined for methine, methylene and methyl carbon. Lipids in the oldest SPE-DOM at 5446 m showed a larger share of ethyl groups and methylene carbon than observed in the other samples. Two-dimensional NMR spectra showed

  10. High-field NMR spectroscopy and FTICR mass spectrometry: powerful discovery tools for the molecular level characterization of marine dissolved organic matter

    Science.gov (United States)

    Hertkorn, N.; Harir, M.; Koch, B. P.; Michalke, B.; Schmitt-Kopplin, P.

    2013-03-01

    High-performance, non-target, high-resolution organic structural spectroscopy was applied to solid phase extracted marine dissolved organic matter (SPE-DOM) isolated from four different depths in the open South Atlantic Ocean off the Angola coast (3° E, 18° S; Angola Basin) and provided molecular level information with extraordinary coverage and resolution. Sampling was performed at depths of 5 m (Angola Current; near-surface photic zone), 48 m (Angola Current; fluorescence maximum), 200 m (still above Antarctic Intermediate Water, AAIW; upper mesopelagic zone) and 5446 m (North Atlantic Deep Water, NADW; abyssopelagic, ~30 m above seafloor) and produced SPE-DOM with near 40% carbon yield and beneficial nuclear magnetic resonance (NMR) relaxation properties, a crucial prerequisite for the acquisition of NMR spectra with excellent resolution. 1H and 13C NMR spectra of all four marine SPE-DOM showed smooth bulk envelopes, reflecting intrinsic averaging from massive signal overlap, with a few percent of visibly resolved signatures and variable abundances for all major chemical environments. The abundance of singly oxygenated aliphatics and acetate derivatives in 1H NMR spectra declined from surface to deep marine SPE-DOM, whereas C-based aliphatics and carboxyl-rich alicyclic molecules (CRAM) increased in abundance. Surface SPE-DOM contained fewer methyl esters than all other samples, likely a consequence of direct exposure to sunlight. Integration of 13C NMR spectra revealed continual increase of carboxylic acids and ketones from surface to depth, reflecting a progressive oxygenation, with concomitant decline of carbohydrate-related substructures. Aliphatic branching increased with depth, whereas the fraction of oxygenated aliphatics declined for methine, methylene and methyl carbon. Lipids in the oldest SPE-DOM at 5446 m showed a larger share of ethyl groups and methylene carbon than observed in the other samples. Two-dimensional NMR spectra showed exceptional

  11. Nonlinear adaptive power-level control for modular high temperature gas-cooled reactors%模块式高温气冷堆的非线性自适应功率控制

    Institute of Scientific and Technical Information of China (English)

    董哲

    2013-01-01

    Because of its inherent safety feature and potential economic competitiveness,the modular high temperature gas-cooled reactor (MHTGR) is regarded as the central part of the next generation of nuclear plant(NGNP).Power-level control is one of the key techniques that guarantee the safe,stable and efficient operation for any nuclear reactors.Since the MHTGR dynamics have the characteristics of strong nonlinearity and uncertainty,which can improve the operation performance.It is significant to develop the nonlinear adaptive power-level control er for the MHTGR.Based on the natural dynamic features beneficial to system stabilization,a novel nonlinear adaptive power-level controller is given for the MHTGR in this paper.It has proved theoretical y that this newly-built control er not only provides the overal asymptotic closed-loop stability,but also is adaptive to the system uncertainty.This control er has been applied in the power-level regulation of the pebble-bed MHTGR of the HTR-PM power plant.Numerical simulation results confirm the feasibility of this control strategy and the relationship between the performance and parameters.%由于具有固有安全性和潜在经济竞争力,模块式高温气冷堆(Modular High Temperature Gas-cooled Reactor, MHTGR)已被视为下一代核能系统的首选堆型之一。功率调节是保证MHTGR安全、稳定和高效运行的关键技术之一,而MHTGR在动态特性上具有非线性强和不确定性大的特点,因此发展MHTGR的非线性自适应功率控制器对于提升运行性能具有重要意义。在充分利用系统自身对镇定有益的动态特性的基础上,本文给出一种新颖的MHTGR非线性自适应功率控制器,并从理论上证明该控制器既可以保证闭环系统的全局渐近稳定性,又对系统不确定性具有自适应功能。数值仿真结果不仅验证了控制器的可行性,而且还给出了调节性能与控制器参数间的关系。

  12. Direct FuelCell/Turbine Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hossein Ghezel-Ayagh

    2008-09-30

    major achievement by successfully completing 8000 hours of operation at the Billings site. The Alpha sub-MW DFC/T power plant unit was returned to the factory for post-operation inspection and analysis. The success of the Alpha Unit operation in the field and achievement of the ultra-high efficiency of 58%, triggered the establishment of a MW-scale commercial product design and development program. Design of a 3 MW (nominal rating) DFC/T Power Plant was completed with an electrical efficiency approaching 60+% LHV of natural gas depending on the design and performance of the gas turbine. Development efforts incorporated lessons learned from the Alpha sub-MW DFC/T power plant demonstration, as well as design features from FCE's commercial product offerings, the DFC1500 and DFC3000 MW-class simple cycle power plants. The 3 MW DFC/T power plant is anticipated to be a superb alternative for large distributed generation applications in locations with high cost-of-electricity.

  13. Study on warpage of a strip level power module in packaging assembly process%封装集成工艺中带状功率器件的翘曲研究

    Institute of Scientific and Technical Information of China (English)

    顾江海; 刘勇; 梁利华

    2012-01-01

    基于子结构法对封装集成工艺中带状功率器件的翘曲问题进行了研究,讨论了子结构法和非子结构法的优劣.采用实验性设计(Design of experiment,DoE),分别研究了嵌入式系统封装中低边芯片和高边芯片厚度、环氧模塑封(Epoxy mold compound,EMC)材料厚度、以及玻璃纤维(Prepreg)材料Z向弹性模量和EMC弹性模量对带状翘曲的影响.结果表明:子结构方法能够高效、简便和准确地模拟带状功率器件的翘曲问题;芯片、EMC厚度的变化对封装工艺中带状功率器件翘曲变形影响较大,Prepreg的Z向弹性模量和EMC的弹性模量E的变化对封装工艺中带状功率器件翘曲变形影响较小.%The warpage of a strip level power module in packaging assembly process is studied based on the substructure method. The comparison between substructure and non-substructure methods is made and discussed. By using design of experiment (DOE) method, the impact of low side (LS) and high side (HS) die thickness, epoxy mold compound (EMC) thickness, as well as the Young's modulus of prepreg and Young's modulus of EMC on the strip level warpage is conducted. It is found that substructure method is able to capture strip level power module warpage characteristics with high efficiency. The simulation results of substructure method agree reasonably well with non-substructure method. The numerical results show that die thickness and EMC thickness have an obvious impact on the warpage of a strip power modules, while the Young's modulus of prepreg and Young's modulus of EMC has less impact on it.

  14. 大数据分析方法在厂级负荷分配中的应用%Application of Big Data Analytics in Plant-level Load Dispatching of Power Plant

    Institute of Scientific and Technical Information of China (English)

    王宁玲; 付鹏; 陈德刚; 杨志平; 杨勇平

    2015-01-01

    传统厂级负荷优化分配以火电机组煤耗曲线为依据,以供电煤耗率最低为目标。考虑到火电机组结构日益复杂,多变的边界条件和运行工况加剧了机组能耗特性的不确定性,给厂级负荷优化分配带来新问题。该文基于火电机组的海量运行数据,引入大数据分析方法,通过模糊粗糙集计算方法提高数据处理的效率,利用决策相关函数评价能耗决策的置信度,获得机组不同边界和运行工况下的能耗特性。将得到的机组供电煤耗率作为厂级负荷动态规划的依据,进而预测负荷优化分配的节煤潜力。结果表明,基于大数据分析方法的厂级负荷分配可有效降低火电厂的供电煤耗率,对火电机组的节能发电调度具有参考意义。%On the basis of coal rate curves, the traditional plant-level load dispatching is fulfilled with the minimum coal rate. Considering the increasing complexity in power unit structure, it is of great uncertainties to describe the energy consumption and difficult for the plant-level load dispatching especially under the varying operation boundary and conditions. With a great volume of operation data of thermal power units, big data-based analytics were introduced. The fuzzy rough set (FRS) method was used to improve the efficiency of data processing, and the decision correlation function was introduced to measure the confidence, so as to derive the coal rate under specific working conditions. Taking such coal rate as the basis of plant-level dynamic load planning, the energy-saving potential was predicted for the optimized load dispatching. The result shows that the load dispatching based on big data analytics is effective to reduce the gross coal rate, making great reference for the energy-saving power generation dispatching.

  15. Power Outages

    Science.gov (United States)

    ... Thunderstorms & Lightning Tornadoes Tsunamis Volcanoes Wildfires Main Content Power Outages This page provides basic safety tips and ... during and after a power outage. Before a Power Outage Build or restock your emergency preparedness kit , ...

  16. Power-constrained supercomputing

    Science.gov (United States)

    Bailey, Peter E.

    As we approach exascale systems, power is turning from an optimization goal to a critical operating constraint. With power bounds imposed by both stakeholders and the limitations of existing infrastructure, achieving practical exascale computing will therefore rely on optimizing performance subject to a power constraint. However, this requirement should not add to the burden of application developers; optimizing the runtime environment given restricted power will primarily be the job of high-performance system software. In this dissertation, we explore this area and develop new techniques that extract maximum performance subject to a particular power constraint. These techniques include a method to find theoretical optimal performance, a runtime system that shifts power in real time to improve performance, and a node-level prediction model for selecting power-efficient operating points. We use a linear programming (LP) formulation to optimize application schedules under various power constraints, where a schedule consists of a DVFS state and number of OpenMP threads for each section of computation between consecutive message passing events. We also provide a more flexible mixed integer-linear (ILP) formulation and show that the resulting schedules closely match schedules from the LP formulation. Across four applications, we use our LP-derived upper bounds to show that current approaches trail optimal, power-constrained performance by up to 41%. This demonstrates limitations of current systems, and our LP formulation provides future optimization approaches with a quantitative optimization target. We also introduce Conductor, a run-time system that intelligently distributes available power to nodes and cores to improve performance. The key techniques used are configuration space exploration and adaptive power balancing. Configuration exploration dynamically selects the optimal thread concurrency level and DVFS state subject to a hardware-enforced power bound

  17. 火电厂燃煤和粉煤灰及炉渣中天然放射性水平分析%The Natural Radioactive Level of the Coal,Coal Cinder and Slag from Power Plants

    Institute of Scientific and Technical Information of China (English)

    谢贵英; 涂传火; 李艾尔肯·阿不列木

    2011-01-01

    The γ-ray spectrometer was used to analyze the natural radioactive level of the coal, coal cinder and slag from China power plant and state power plant in Urumqi. The average value of 226Ra 、232Th、and40K of coal is 5.54 、 3.51、 69.15Bq/Kg , the coal cinder is 26.99 、 15.89、 122.69Bq/Kg , the slag from China power plant is 28.79、15.98、 116.72Bq/Kg . The result reveals that the coal cinder's application range has no limit according to national standard.%本文采用低本底γ能谱仪对乌鲁木齐市华电和国电两个电厂的燃煤、粉煤灰和炉渣中的天然放射性核素含量进行了测量.测量结果:226Ra、232Th、40K含量的平均值,煤中分别为5.54、3.51、69.15Bq/Kg,粉煤灰中分别为26.99、15.89、122.69Bq/Kg,炉渣样中分别为28.79、15.98、116.72Bq/Kg.并依据国家标准对粉煤灰进行分类,结果表明,粉煤灰的使用不受限制.

  18. Development and Application of Mine-used Wind Power Automatic Liquid Level Control Drainage Switch%矿用风动力液位自控排水开关的研制与应用

    Institute of Scientific and Technical Information of China (English)

    秦加增; 玄登程

    2014-01-01

    Mine submersible pump is widely used in the coal mine drainage, but over setting of submersible pump has caused huge waste of mine power supply, equipment using and the energy consumption. In order to achieve the multi-win goal of mine drainage, safety in production and energy conservation, the submersible pump wind power automatic liquid level control drainage switch is designed, and its principle and structure are introduced.%矿井潜水泵广泛使用于煤矿井下排水,过多的布置使用给矿井供电、设备使用和能源消耗造成极大的浪费。为达到矿井排水与安全生产和能源节约的多项共赢,设计制作了潜水泵风动力液位自控排水开关,并介绍其原理和结构。

  19. Analysis of Information Security Risks Internal Control Management System of the City Level Power Grid Enterprise%浅析地市级电网企业信息安全风险内控管理体系建设

    Institute of Scientific and Technical Information of China (English)

    蒋友志

    2012-01-01

    在市场经济体制促进下,电网企业的信息安全管理体制迎来了新发展。文中阐述了ISO/IEC27001标准下电网企业信息安全风险内控管理需要的内容与体系,并通过某地级市的电网企业为研究对象,构建出科学合理的信息安全管理体系,对使用中出现的问题提出了合理建议。%With the promotion of the market economy system, the power grid enterprise information security manage- ment system has new developed. This paper elaborates the need contents and system in the ISO/IEC 27001 standard, and taking a city level power grid enterprise as the research object, construct scientific and reasonable information security man- agement system, and puts forward reasonable suggestions for problems in using.

  20. Electric power annual 1993

    Energy Technology Data Exchange (ETDEWEB)

    1994-12-08

    This report presents a summary of electric power industry statistics at national, regional, and state levels: generating capability and additions, net generation, fossil-fuel statistics, retail sales and revenue, finanical statistics, environmental statistics, power transactions, demand side management, nonutility power producers. Purpose is to provide industry decisionmakers, government policymakers, analysts, and the public with historical data that may be used in understanding US electricity markets.

  1. 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

  2. 热能与动力工程专业英语分层次教学模式的探讨%Probe into the Teaching of Specialty English in Accordance with Different Levels in Thermal Energy & Power Engineering

    Institute of Scientific and Technical Information of China (English)

    孙运兰; 朱宝忠; 刘小芳

    2011-01-01

    在热能与动力工程专业英语教学中,由于学生的英语水平参差不齐,教师应因材施教,实施分层教学,调动学生学习兴趣,激发学生自主学习的动机,提高教学质量。%In the teaching of specialty English in thermal energy and power engineering,because of the different levels of students,teachers should teach students in accordance with their aptitude,arouse their interests in study and stimulate their motive of self-learning to promote the teaching quality.

  3. Deadbeat Predictive Direct Power Control of Single-phase Three-level Pulse Rectifiers%单相三电平脉冲整流器无差拍预测直接功率控制

    Institute of Scientific and Technical Information of China (English)

    马俊鹏; 宋文胜; 王顺亮; 冯晓云

    2015-01-01

    In order to improve the controller’s dynamic response and precision of single-phase three-level pulse rectifier applied in China railways high-speed 2 (CRH2) electric multiple units, a single-phase three-level pulse rectifier was firstly modeled with mathematical expression. Then the operating principle of direct power control (DPC) based on PI controller with the fixed switching frequency was analyzed. On this basis, a single-phase deadbeat DPC with autoregressive power prediction method was proposed. Compared with the traditional PI DPC method, the proposed DPC method can not only reduce the complexity of hardware design and software programming without the main voltage’s phase detector, such as phase-locked loop (PLL), but also improve dynamic response of the rectifier with load change with active and reactive power autoregressive prediction. Furthermore, a single-phase three-level space vector pulse width modulation (SVPWM) embedded neutral point voltage balance was combined with the proposed deadbeat predictive DPC method as the control system of single-phase three-level pulse rectifier. Finally, The deadbeat predictive DPC and the traditional DPC with PI controller were compared and verified in computer simulation and hardware-in-loop experimental test. A comparison of simulation and experimental results verifies the feasibility and effectiveness of the adopted deadbeat predictive DPC method.%以我国CRH2(China railways highspeed 2)型高速动车组的单相三电平脉冲整流器为研究对象,以提高其动态响应速度及控制精度为目的,该文首先建立单相三电平脉冲整流器数学模型,分析传统基于比例积分(proportional-integral, PI)控制器的定频直接功率控制(direct power control,DPC)的工作原理,在此基础上,提出一种基于自回归算法的单相无差拍功率预测DPC算法。与传统PI定频DPC算法相比,该DPC算法无需网压相位检测装置,如锁相环(phase locked

  4. Control of a deareador level of a thermoelectric power station using modern control techniques; Control de nivel de un deareador de una central termoelectrica utilizando tecnicas de control moderno

    Energy Technology Data Exchange (ETDEWEB)

    Chavez Estrada, Jose Israel

    1997-01-01

    The present work shows the implementation of the scheme of predictive control IMC (Internal Model Control) in order to control the level of the deareador of a combined cycle thermoelectric power station of (C.C.T.S.). The implementation has the purpose of looking for alternative strategies of control to the classic ones (PID`s) that more efficiently control the variables of interest, in addition to getting into the new control techniques of control. Following the philosophy of predictive control IMC the form to applying this technique is shown, as well as the implementation of this type of controllers. A comparison of predictive control IMC is made with the scheme of conventional control (three control elements PID`s ) used at present to control the level of the deareador in the Combined Cycle Thermoelectric Power stations of Dos Bocas, Veracruz, Mexico and of Gomez Palacio, Durango, Mexico. [Espanol] El presente trabajo muestra la implementacion del esquema de control predictivo IMC (Control con Modelo Interno) con el objeto de controlar el nivel del deareador de una Central Termoelectrica de Ciclo Combinado (C.T.C.C.). La implementacion tiene la finalidad de buscar estrategias de control alternas a las clasicas (PID`s) que controlen mas eficientemente la variable de interes, ademas de incursionar en las nuevas tecnicas de control. Siguiendo la filosofia del control predictivo IMC se muestra la forma de aplicar esta tecnica, asi como la implementacion de este tipo de controladores. Se hace una comparacion del control predictivo IMC con el esquema de control convencional (control de tres elementos PID`s) utilizando actualmente para controlar el nivel del deareador en las centrales termoelectricas de ciclo combinado de Dos Bocas, Veracruz y de Gomez Palacio, Durango en Mexico.

  5. High-power targets: experience and R&D for 2 MW

    CERN Document Server

    Hurh, P; Davenne, T; Densham, C; Loveridge, P; Simos, N

    2012-01-01

    High-power particle production targets are crucial elements of future neutrino and other rare particle beams. Fermilab plans to produce a beam of neutrinos (LBNE) with a 2.3 MW proton beam (Project X). Any solid target is unlikely to survive for an extended period in such an environment - many materials would not survive a single beam pulse. We are using our experience with previous neutrino and antiproton production targets, along with a new series of R&D tests, to design a target that has adequate survivability for this beamline. The issues considered are thermal shock (stress waves), heat removal, radiation damage, radiation accelerated corrosion effects, physics/geometry optimization and residual radiation.

  6. Power grid complexity

    CERN Document Server

    Mei, Shengwei; Cao, Ming

    2011-01-01

    This book introduces self-organized criticality (SOC) theory and complex network theory and applies them to power systems. It examines four blackout models based on SOC theory and studies the SOC of power systems at both the macroscopic and microscopic levels.

  7. Offshore Wind Power Data

    DEFF Research Database (Denmark)

    Cutululis, Nicolaos Antonio; Litong-Palima, Marisciel; Zeni, Lorenzo;

    2012-01-01

    Wind power development scenarios are critical when trying to assess the impact of the demonstration at national and European level. The work described in this report had several objectives. The main objective was to prepare and deliver the proper input necessary for assessing the impact of Demo 4...... – Storm management at national and European level. For that, detailed scenarios for offshore wind power development by 2020 and 2030 were required. The aggregation level that is suitable for the analysis to be done is at wind farm level. Therefore, the scenarios for offshore wind power development offer...... details about the wind farms such as: capacity and coordinates. Since the focus is on the impact of storm fronts passage in Northen Europe, the offshore wind power scenarios were estimated only for the countries at North and Baltic Sea. The sources used are public sources, mentioned in the reference list...

  8. Influence of the power level of an ultra-sonic system on dental cavity preparation Influência do nível de potência de um sistema de ultra-som em preparos cavitários

    Directory of Open Access Journals (Sweden)

    Érika Botelho Josgrilberg

    2007-12-01

    Full Text Available The aim of this study was to evaluate the shape of dental cavities made with the CVDentus® system using different ultrasound power levels. One standard cavity was made on the buccal aspect of 15 bovine incisors with a CVDentus® cylindrical bur (82142. The sample was divided into three groups: G1 - ultrasound with power II; G2 - ultrasound with power III; and G3 - ultrasound with power IV. A standardizing device was used to obtain standardized preparations and ultrasound was applied during one minute in each dental preparation. The cavities were sectioned in the middle, allowing observation of the cavity’s profile with a magnifying glass, and width and depth measurement using the Leica Qwin program. The Kruskal-Wallis (p O objetivo deste estudo foi avaliar o formato dos preparos cavitários realizados com o sistema CVDentus® utilizando potências variadas do ultra-som. Uma cavidade padronizada foi realizada na face vestibular de 15 incisivos bovinos utilizando as pontas cilíndricas CVDentus® (82142. A amostra foi dividida em 3 grupos: G1 - ultra-som com potência II; G2 - ultra-som com potência III; e G3 - ultra-som com potência IV. Foi utilizada uma máquina padronizadora de preparos cavitários e o ultra-som foi aplicado durante 1 minuto em cada preparo. As cavidades foram seccionadas no centro, permitindo a visualização do perfil cavitário em uma lupa estereoscópica, e esse foi medido em largura e profundidade por meio do programa Leica Qwin. O teste estatístico Kruskal-Wallis (p < 0,05 e o método de Dunn demonstraram diferenças entre os formatos das cavidades produzidas com as potências III e IV. Entretanto, as cavidades realizadas com a potência III apresentaram dimensões semelhantes às da ponta utilizada. Concluiu-se que a potência indicada pelo fabricante (III é a mais adequada para uso do sistema CVDentus®.

  9. Measurement of Pulsed Power Supply

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Power supply system is an important subsystem of CSR. To apply for running, the parameters of power supply must be fit the design’s demands. We have tested all prototype of power supply as follows.The DC stability measurement is that the power supply runs in certain current level from the lower value to the normal value. In every current level, we acquire about 550 data by digital meter (model 7081) in 8 h.

  10. Power sharing

    International Nuclear Information System (INIS)

    The World Commission on Dams set out to review the development effectiveness of large dams and assess the alternatives for water resources and energy development. We undertook eight detailed case studies of large dams and prepared country reviews for India and China, plus a briefing paper on Russia and the newly independent states. A survey of 125 large dams was also developed, along with 17 thematic reviews on social, environmental and economic issues; on alternatives to dams; and on governance and institutional processes. We learned that large dams built to deliver hydropower had tended to perform close to but still below targets for power generation. They generally met their financial targets, but demonstrated variable economic performance relative to targets. Ecosystem impacts were generally found to be more negative than positive for dams in general (including those designed for water supply, irrigation and flood control). They have, in many cases, led to significant loss of species and ecosystems. We found that all reservoirs that have been sampled by scientists emit greenhouse gases - as do natural lakes - from rotting vegetation and carbon inflows from the catchment area. The scale of these emissions is highly variable. Data from a hydropower dam in Brazil showed that the gross level is significant compared to emissions from equivalent thermal power plants. However, in other reservoirs (notably those in boreal zones) gross emissions of greenhouse gases are significantly lower than the thermal alternative. Clearly more research is needed to demonstrate the capacity for hydropower to offset climate change

  11. Power Controller

    Science.gov (United States)

    1982-01-01

    The device called the Power Factor Controller (PFC) offers exceptional energy conservation potential by virtue of its ability to sense shifts in the relationship between voltage and current flow, and to match them with the motor's need. Originating from the solar heating/cooling program, the PFC senses a light load, it cuts the voltage level to the minimum needed which in turn reduces current flow and heat loss. Laboratory tests showed that the PFC could reduce power used by six to eight percent under normal motor loads, and as much as 65 percent when the motor was idling. Over 150 companies have been granted NASA licenses for commercial use of this technology. One system that utilizes this technology is the Vectrol Energy System, (VES) produced by Vectrol, Inc. a subsidiary of Westinghouse. The VES is being used at Woodward & Lothrop, on their escalators. Energy use is regulated according to how many people are on the escalator at any time. It is estimated that the energy savings are between 30 to 40 percent.

  12. Power beaming providing a space power infrastructure

    International Nuclear Information System (INIS)

    This paper, based on two levels of technology maturity, applied the power beaming concept to four panned satellite constellations. The analysis shows that with currently available technology, power beaming can provide mass savings to constellations in orbits ranging from low-Earth orbit to geosynchronous orbit. Two constellations, space surveillance and tracking system and space-based radar, can be supported with current technology. The other two constellations, space-based laser array and boost surveillance and tracking system, will require power and transmission system improvements before their breakeven specific mass is achieved. A doubling of SP-100 conversion efficiency from 10 to 20% would meet or exceed breakeven for these constellations

  13. 西安灞桥燃煤电厂周围土壤天然放射性水平%Natural Radioactivity Level in Soil Around Baqiao Coal-fired Power Plant

    Institute of Scientific and Technical Information of China (English)

    赵彩凤; 卢新卫; 杨光; 李楠; 任春辉

    2012-01-01

    Natural radioactivity in soil around Baqiao coal - fired power plant had been measured by using a Nal ( Tl) γ - ray spectrometry. The results show that the specific activity of 226Ra,232Th and 40K in soil samples ranges from 27.60 to 48.78, 44. 39 to 61. 39 and 640.19 to 992. 25 Bq/kg with an average of 36.07 , 51. 13 and 733.91 Bq/kg, respectively. The average activity of 226Ra in soil around the power plant is greater than the average of Shaanxi soil, while slightly less than the average of Chinese soil. The average activity of Th and K in the studied soil samples are higher than the average level of Shaanxi soil and Chinese soil. The concentrations of 226Ra and 232Th in soil samples collected within 1000 m sites to coal - fired power plant boundary show no significantly spatial differences, whereas K concentration in soil samples collected from 100 m sites is less than from 400 m and 1 000 m sampling sites. The evaluation results of radium equivalent activity, air absorbed dose rate and annual effective dose rate show that coal - fired power plant affected the natural radioactivity level of surrounding soil, but natural radioactivity of soil is in normal level.%应用低本底多道γ能谱仪测定了燃煤电厂周围土壤中天然放射性核素226 Ra、232Th和40K的比活度,评价了其辐射危害.测定结果表明,土壤中226 Ra、232Th和40K的比活度分别为27.60~ 48.78、44.39~ 61.39和640.19~ 992.25 Bq/kg,平均值分别为36.07、51.13和733.91 Bq/kg.电厂周围土壤中226Ra比活度大于陕西土壤平均水平,稍小于全国土壤平均值;232 Th和40K比活度均大于陕西省土壤和全国土壤平均水平.在距离电厂1 000 m范围内,土壤中226Ra和232Th无明显空间差异,而40K比活度在距电厂100 m处土壤中明显低于400 m和1000m处.等效镭活度、空气吸收剂量率和年有效剂量率评价结果表明,燃煤发电对灞桥电厂周围土壤放射性有一定影响,但放射性水平处于正常.

  14. Power Networks

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Present States and Characteristics Since implementing reform and open policy,power industry in China has implemented the policy of separating govemment functions from enterprises, taking provincial power sectors as independent entities,integrating power networks, unified power dispatching and raising fund from various sources”, which has brought about rapid growth of power industry. With 12 years of continuous annual growth over 10,000 MW since 1988, the national total installed capacity reached 319.320.9 MW with an annual generation of 1368.482 TWh in 2000. To cope with the rapid growth of power source. all power networks in China have expanded correspondingly.

  15. Noise Exposure Level in Workers of a Pumped Storage Power Station%某抽水蓄能电站运行人员噪声暴露水平检测与分析

    Institute of Scientific and Technical Information of China (English)

    刘跟生

    2013-01-01

    [ Objective ] To evaluate noise exposure levels of workers in pumped storage power stations. [ Methods ] Individual noise exposure levels in 2 patrolling workplaces and 1 control room and in both operating and alternative conditions were measured. A mathematical calculation based on individual exposure level and exposure time was used to evaluate workers' noise exposure of 42 h per week which was then converted to the time equivalent continuous A-weighted sound pressure level (Laeq) of 40 h per week. [ Results ] In this study, the noise exposure levels in 2 patrolling workplaces and 1 control room were measured 3 times a day in both operating and alternative conditions. The workers' Laeq of 42 h per week was 62.1 dB (A) . After conversion, the workers' Laeq of 40h per week was 62.3 dB (A). [ Conclusion ] The noise exposure levels of workers in pumped storage power station do not exceed the occupational exposure limit of 85dB (A) prescribed in Occupational exposure limits for hazardous agents in the workplace Part 2: Physical agents.%[目的]分析抽水蓄能电站运行人员的噪声暴露水平. [方法]检测运行人员在运行工况及备用工况每次巡检时的接噪强度以及巡检后控制室的噪声强度,结合运行人员在不同情况下的接噪时间,计算运行人员在四值三运转的工作制度下,1周42h接触噪声强度的等效声级,进而换算至1周40h接触噪声强度的等效声级. [结果]本研究共检测6次运行工况及3次备用工况下的个体噪声及控制室噪声,经过计算分析,得出运行人员1周42h接触噪声的等效连续A声级为62.1 dB(A),换算至1周40h接触噪声的等效连续A声级为62.3 dB(A). [结论]抽水蓄能电站运行人员的噪声暴露水平未超过《工作场所有害因素职业接触限值第2部分:物理因素》(GBZ 2.2-2007)中规定的职业接触限值85dB(A).

  16. Power marketing and renewable energy

    International Nuclear Information System (INIS)

    Power marketing refers to wholesale and retail transactions of electric power made by companies other than public power entities and the regulated utilities that own the generation and distribution lines. The growth in power marketing has been a major development in the electric power industry during the last few years, and power marketers are expected to realize even more market opportunities as electric industry deregulation proceeds from wholesale competition to retail competition. This Topical Issues Brief examines the nature of the power marketing business and its relationship with renewable power. The information presented is based on interviews conducted with nine power marketing companies, which accounted for almost 54% of total power sales by power marketers in 1995. These interviews provided information on various viewpoints of power marketers, their experience with renewables, and their respective outlooks for including renewables in their resource portfolios. Some basic differences exist between wholesale and retail competition that should be recognized when discussing power marketing and renewable power. At the wholesale level, the majority of power marketers stress the commodity nature of electricity. The primary criteria for developing resource portfolios are the same as those of their wholesale customers: the cost and reliability of power supplies. At the retail level, electricity may be viewed as a product that includes value-added characteristics or services determined by customer preferences

  17. Modernization of the feedwater heaters control level of the Almaraz I Nuclear Power Plant by OVATION system; Modernizacion del control de nivel de los calentadores de agua de alimentacion de C.N. Almaraz I mediante el sistema OVATION

    Energy Technology Data Exchange (ETDEWEB)

    Madronal Rodriguez, E.; Cabrero Munoz, J. E.

    2010-07-01

    As a result of the process of technological renovation of the heaters system and the power increase project, Almaraz Nuclear Power Plant has made several design changes in the feedwater heaters system. Within these changes, the old heaters control loops are replaced because the new power will increase the heaters drainage caudal. This modernization is carried out using the OVATION control system.

  18. 双三电平永磁直驱风力发电系统控制策略研究%Dual Three-level Permanent Magnet Direct Drive Wind Power System Control Strategy

    Institute of Scientific and Technical Information of China (English)

    王斌; 王峰; 刘毅; 张杰

    2011-01-01

    为满足变流器容量需求并获取较低的电流谐波指标,降低开关损耗,达到良好的并网要求,直驱式风力发电系统采用永磁同步发电机(PMSG)和双三电平变流器相结合的拓扑结构.基于PMSG d,q坐标系下的数学模型,机侧变换器运用简化的空间矢量脉宽调制技术并结合PMSG的最大转矩电流比控制策略,充分利用凸极效应,提高系统运行效率,网侧变换器采用电压电流双闭环控制策略.利用Matlab软件建立直驱式永磁同步风力发电系统的仿真模型,并对风速突变时系统的动态特性进行研究.仿真结果表明,所建立模型具有较好的动态特性并验证了控制系统的正确性及有效性.%To meet the requirement for the capacity, low current harmonic level and low switching loss, direct-drive wind power generation system employed the topology which combined the permanent magnet synchronous generator (PMSG) and dual three-level PWM full-size converter.Based on d,q axis mathematical model of PMSG,in order to take full advantages of saliency effects, improve efficiency, the generator side adopts simplified space vector pulse width modulation technology combined with maximum torque per ampere control scheme.The grid side employes the dual close-loop control strategy which are the inner current-loop and the outer voltage-loop. The model of direct-drive wind power generation system is realized with the engineering software, Matlab for the case of wind speed stepping change shows the excellent dynamic performance of the model, in the same time, verifies the correctness and feasibili ty of the control strategy.

  19. Availability Analysis of Nuclear Power System With Performance Degradation and Multi-level Support Capacity%考虑性能退化和多级保障的核动力系统可用度分析

    Institute of Scientific and Technical Information of China (English)

    尚彦龙; 蔡琦; 赵新文; 赵宇光

    2014-01-01

    The availability analysis which combines universal generating function (UGF) with Markov state transition theory was proposed to nuclear power system with performance degradation and multi-level support capacity .The system logical model and performance state combination model were constructed by UGF . Furthermore , the computational expression for component state probability based on Markov method was constructed considering performance degradation and multi-level support capacity .And then the model was embedded into the logic model and performance state combination model by UGF . This combined model was used in availability analysis of an actual example with different performance demands , and the influence of maintenance condition to system availability was also analyzed .The results show that this method captures the operational and maintenance characteristics . T he obtained results can provide guidance to nuclear power system operation , management , maintenance decision-making and support condition analysis .%研究了将通用发生函数理论与M arkov过程方法相结合的方法对考虑性能退化和多级保障的核动力系统进行可用度分析。基于 M arkov过程方法建立考虑性能退化和多级保障的设备状态概率模型,并将其嵌入由发生函数构建的系统逻辑关系模型和性能状态组合模型,从而分析系统在不同性能需求条件下的可用度,并分析不同修理条件对系统可用度的影响。所建立的模型反映了核动力系统的使用特点和维修保障特性,研究方法和分析结论能为核动力系统的使用管理、维修决策及保障条件分析提供理论指导和依据。

  20. 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...... level should be economic and can be a provided by different tools such as developing new reserve scheduling techniques, demand response, using storage units, facilitating the capacity of cross-border interconnections and so on. These subjects are addressed in this PhD dissertation. In the first study...