Science.gov

Sample records for power ascension strategy

  1. Power ascension strategy following a reactor trip during EOC coastdown

    SciTech Connect

    Beard, C.L.; Heibel, M.D. ); Lesnick, D.C. )

    1992-01-01

    The difficulties associated with returning a reactor to the pretrip power level following a reactor trip during an end-of-cycle (EOC) power coastdown maneuver, and maintaining it once achieved, have caused utilities to abandon the restart and enter their refueling outages ahead of schedule. The Commonwealth Edison Company (CECo) Braidwood and Byron units have experienced reactor trips during EOC power coastdown maneuvers and have successfully performed restarts. The installation of the BEACON core monitoring system, which provides core monitoring, measurement reduction, core analysis and follow, and core prediction capability utilizing a very fast and accurate three-dimensional nodal code, at the CECo Byron, Braidwood, and Zion stations allows the reactor engineers at these units to accurately determine reactor response. The capabilities of the BEACON system allow an optimal return to power strategy to be developed and continuously updated. This paper presents a method for establishing the optimal return to power strategy utilizing the BEACON system.

  2. Final Report: Phase II Geothermal Exploration and Geothermal Power Plant Update for Ascension Island, South Atlantic Ocean

    SciTech Connect

    Nielson, D.L.; Sibbett, B.S.; Shane, M.K.; Whitbeck, J.F.

    1984-07-01

    The Phase I study of the geothermal potential of Ascension Island concluded that the possibility of a geothermal resource existing under the island was excellent. This conclusion was based on the presence of young volcanic rocks (a heat source close to the surface), an ample supply of water from the sea, and high permeability of many of the rocks which make up the island. The assumption was made that the resource would be similar to geothermal systems in the Azores or Japan, and a conceptual design of a power plant to utilize the resource was prepared upon which cost estimates and an economic analysis were subsequently performed. The results of the economic analysis were very favorable, and the Air Force decided to proceed into Phase II of the project. Under Phase II, an exploration program was designed and carried out. The purpose of the program was to ascertain whether or not a geothermal resource existed beneath Ascension island and, to the extent possible, to evaluate the quality of that resource. The exploration involved a detailed aeromagnetic survey of the island, reconnaissance and detailed electrical resistivity surveys, and drilling of holes for the measurement of temperatures. These methods have confirmed the existence of geothermal activity beneath Ascension. Measured temperature gradients and bottom hole temperatures as well as chemical geothermometers indicate temperatures sufficient for the generation of electricity within reasonable drilling depths. This report documents those conclusions and the supporting data. This report also documents the results of the power plant update with new data supplied from the Phase II exploration activities on the island. The power plant scenario has been changed to reflect the fact that the resource temperature may not be as high as that originally assumed in the Phase I study, the location of the production wells will in all likelihood be farther from the existing Air Force facilities--either north of Grazing

  3. Knee extensor and flexor muscle power explains stair ascension time in patients with unilateral late-stage knee osteoarthritis: a cross-sectional study.

    PubMed

    Valtonen, Anu M; Pöyhönen, Tapani; Manninen, Mikko; Heinonen, Ari; Sipilä, Sarianna

    2015-02-01

    To determine the extent of asymmetrical deficits in knee extensor and flexor muscles, and to examine whether asymmetrical muscle deficits are associated with mobility limitations in persons with late-stage knee osteoarthritis (OA). Cross-sectional. Research laboratory. A clinical sample (N=56; age range, 50-75y) of eligible persons with late-stage knee OA awaiting knee replacement. Not applicable. Knee extensor and flexor power and torque assessed isokinetically; thigh muscle cross-sectional area (CSA) assessed by computed tomography; mobility limitation assessed by walking speed and stair ascension time; and pain assessed with the Western Ontario and McMaster Universities Osteoarthritis Index questionnaire. The asymmetrical deficits in knee extensor and flexor power and torque were between 18% and 29% (P<.001). Regarding the thigh muscle CSA, the asymmetrical deficit was 4% (P<.001). Larger asymmetrical knee extensor power deficits and weaker knee extensor and flexor power on the contralateral side were associated with slower stair ascension times. Moreover, weaker knee extensor and flexor power on the ipsilateral side were associated with slower stair ascension times. Greater knee pain in the OA joint was independently associated with slower stair ascending time in both models. The knee extensor and flexor muscle power of both the ipsilateral and contralateral sides and the pain in the OA knee were independently associated with stair ascension times. These results highlight the importance of assessing muscle power on both sides and knee pain in the prevention of mobility limitations in patients with knee OA. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  4. Six Months in Ascension

    NASA Astrophysics Data System (ADS)

    Black Gill, Isobel Sarah; Gill, David

    2010-06-01

    Introduction David Gill; 1. Why we went; 2. The voyage; 3. St. Helena; 4. What Ascension looked like; 5. Ascension past and present; 6. Round about Garrison; 7. A night on the Clinker; 8. Change and check; 9. Mars Bay; 10. A Sunday scene; 11. The opposition of Mars; 12. The sea-shore and the rollers; 13. Green Mountain; 14. Sunday at the mountain; 15. Why we had only a gallon of water; 16. Trips from Garden Cottage; 17. Mars Bay without a cook; 18. Wide-awake fair; 19. Last days at Mars Bay; 20. Christmas in Garrison; 21. About the Kroomen; 22. Clinker Cemeteries; 23. Christmas holidays; 24. The Devil's riding school; 25. Homeward bound.

  5. Possessor Ascension in Dakota Sioux.

    ERIC Educational Resources Information Center

    Pinson, Thomas M.

    A study of Dakota Sioux presents evidence for Possessor Ascension. In this construction, a nominal that is semantically a possessor is syntactically not a constituent of the noun phrase but a constituent of the clause. The report first discusses the universal characterization of Possessor Ascension in the framework of relational grammar, and…

  6. Water Resources of Ascension Parish

    USGS Publications Warehouse

    Griffith, J.M.; Fendick, R.B.

    2009-01-01

    Ascension Parish, located along the banks of the Mississippi River in south-central Louisiana, contains fresh groundwater and surface-water resources. In 2005, about 202 million gallons per day (Mgal/d) were withdrawn from water sources in Ascension Parish. About 94 percent (190 Mgal/d) was withdrawn from surface water, and 6 percent (12 Mgal/d) was withdrawn from groundwater. Additional water is supplied to Ascension Parish for public-supply use from East Baton Rouge Parish. Withdrawals for industrial use accounted for 95 percent (192 Mgal/d) of the total water withdrawn. Withdrawals for other uses included public-supply (4 Mgal/d), rural-domestic (3 Mgal/d), and aquaculture (3 Mgal/d). Water withdrawals in the parish generally increased from 1960 to 1995 and decreased from 1995 to 2005. This fact sheet summarizes basic information on the water resources of Ascension Parish, La. Information on groundwater and surface-water availability, quality, development, use, and trends is based on previously published reports listed in the references section.

  7. Power Subscription Strategy

    SciTech Connect

    None, None

    1998-12-21

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

  8. Geothermal potential of Ascension Island, south Atlantic. Phase I. Preliminary examination

    SciTech Connect

    Sibbett, B.S.; Neilson, D.L.; Ramsthaler, J.H.; Shane, M.K.

    1982-09-01

    A preliminary evaluation of the potential for an economic geothermal resource at Ascension Island was completed. It is concluded that there is a high potential for the presence of a geothermal resource under the Island. A conceptual plant has been designed assuming the resource potential located near Gannet Hill is developed. A 7% discounted payback of 5.9 years was calculated for the baseline geothermal plant. Geothermal development can be easily integrated into the Ascension Island power system in that a selection of small, portable, skid mounted, turn key power geothermal generating systems are commercially available. Geologic findings and plant analysis are summarized.

  9. Geothermal Gradient Drilling and Measurements Ascension Island, South Atlantic Ocean

    SciTech Connect

    Sibbett, B.S.; Nielson, D.L.; Adams, M.C.

    1984-07-01

    This technical report on the Phase II geothermal exploration of Ascension Island documents the data collected during thermal gradient drilling and the subsequent thermal and fluid chemical investigations. It also documents the completion of the Phase II exploration strategy which was proposed at the end of the Phase I--Preliminary Examination of Ascension Island. The thermal gradient drilling resulted in seven holes which range from 206 to 1750 ft (53-533 m) deep, with a cumulative footage of 6563 ft (2000 m). The drilling procedure and the problems encountered during the drilling have been explained in detail to provide information valuable for any subsequent drilling program on the island. In addition, the subsurface geology encountered in the holes has been documented and, where possible, correlated with other holes or the geology mapped on the surface of the island. Temperatures measured in the holes reach a maximum of 130 F (54.4 C) at 1285 ft (391.7 m) in hole GH-6. When the temperatures of all holes are plotted against elevation, the holes can be classed into three distinct groups, those which have no thermal manifestations, those with definite geothermal affinities, and one hole which is intermediate between the other two. From consideration of this information, it is clear that the highest geothermal potential on the island is in the Donkey Flat area extending beneath Middleton Ridge, and in the Cricket Valley area. Because of the greater drilling depths and the remote nature of the Cricket Valley area, it is recommended that future exploration concentrate in the area around Middleton Ridge.

  10. Out of the SHADOZ: Ascension Ozone in the Spotlight

    NASA Astrophysics Data System (ADS)

    Thompson, A. M.; Stauffer, R. M.; Witte, J. C.; Ashburn, C. E.

    2016-12-01

    The Ascension Island (8S, 15W) SHADOZ (Southern Hemisphere Additional Ozonesondes) station is the only one in the south Atlantic. This places it often in the descending branch of the Walker Circulation; as such, it is susceptible to impacts from ENSO variability. Ascension is also at a crossroads of pollution transport from South America and both northern and southern Africa. Ozonesondes and radiosondes have been launched at Ascension during the TRACE-A period (1990-1992) and for SHADOZ (1998-2010, 2016-). We show that influences of the above-mentioned sources of variability can be seen in free tropospheric and lower stratospheric ozone profiles. We compare the early 1990s and later SHADOZ ozone records. Two phenomena of early 2016 are investigated using Ascension sondes: an unusual set of free tropospheric ozone profiles from late March-early April soundings; the anomalous Quasi-Biennial Oscillation recently described by Paul A. Newman and coworkers.

  11. An odyssey of the green sea turtle: Ascension Island revisited

    PubMed Central

    Bowen, Brian W.; Meylan, Anne B.; Avise, John C.

    1989-01-01

    Green turtles (Chelonia mydas) that nest on Ascension Island, in the south-central Atlantic, utilize feeding grounds along the coast of Brazil, more than 2000 km away. To account for the origins of this remarkable migratory behavior, Carr and Coleman [Carr, A. & Coleman, P. J. (1974) Nature (London) 249, 128-130] proposed a vicariant biogeographic scenario involving plate tectonics and natal homing. Under the Carr-Coleman hypothesis, the ancestors of Ascension Island green turtles nested on islands adjacent to South America in the late Cretaceous, soon after the opening of the equatorial Atlantic Ocean. Over the last 70 million years, these volcanic islands have been displaced from South America by sea-floor spreading, at a rate of about 2 cm/year. A population-specific instinct to migrate to Ascension Island is thus proposed to have evolved gradually over tens of millions of years of genetic isolation. Here we critically test the Carr-Coleman hypothesis by assaying genetic divergence among several widely separated green turtle rookeries. We have found fixed or nearly fixed mitochondrial DNA (mtDNA) restriction site differences between some Atlantic rookeries, suggesting a severe restriction on contemporary gene flow. Data are consistent with a natal homing hypothesis. However, an extremely close similarity in overall mtDNA sequences of surveyed Atlantic green turtles from three rookeries is incompatible with the Carr-Coleman scenario. The colonization of Ascension Island, or at least extensive gene flow into the population, has been evolutionarily recent. Images PMID:16594013

  12. An odyssey of the green sea turtle: Ascension Island revisited.

    PubMed

    Bowen, B W; Meylan, A B; Avise, J C

    1989-01-01

    Green turtles (Chelonia mydas) that nest on Ascension Island, in the south-central Atlantic, utilize feeding grounds along the coast of Brazil, more than 2000 km away. To account for the origins of this remarkable migratory behavior, Carr and Coleman [Carr, A. & Coleman, P. J. (1974) Nature (London) 249, 128-130] proposed a vicariant biogeographic scenario involving plate tectonics and natal homing. Under the Carr-Coleman hypothesis, the ancestors of Ascension Island green turtles nested on islands adjacent to South America in the late Cretaceous, soon after the opening of the equatorial Atlantic Ocean. Over the last 70 million years, these volcanic islands have been displaced from South America by sea-floor spreading, at a rate of about 2 cm/year. A population-specific instinct to migrate to Ascension Island is thus proposed to have evolved gradually over tens of millions of years of genetic isolation. Here we critically test the Carr-Coleman hypothesis by assaying genetic divergence among several widely separated green turtle rookeries. We have found fixed or nearly fixed mitochondrial DNA (mtDNA) restriction site differences between some Atlantic rookeries, suggesting a severe restriction on contemporary gene flow. Data are consistent with a natal homing hypothesis. However, an extremely close similarity in overall mtDNA sequences of surveyed Atlantic green turtles from three rookeries is incompatible with the Carr-Coleman scenario. The colonization of Ascension Island, or at least extensive gene flow into the population, has been evolutionarily recent.

  13. Space nuclear power: a strategy for tomorrow

    SciTech Connect

    Buden, D.; Angelo, J. Jr.

    1981-01-01

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

  14. Integrated Surface Power Strategy for Mars

    NASA Technical Reports Server (NTRS)

    Rucker, Michelle

    2015-01-01

    A National Aeronautics and Space Administration (NASA) study team evaluated surface power needs for a conceptual crewed 500-day Mars mission. This study had four goals: 1. Determine estimated surface power needed to support the reference mission; 2. Explore alternatives to minimize landed power system mass; 3. Explore alternatives to minimize Mars Lander power self-sufficiency burden; and 4. Explore alternatives to minimize power system handling and surface transportation mass. The study team concluded that Mars Ascent Vehicle (MAV) oxygen propellant production drives the overall surface power needed for the reference mission. Switching to multiple, small Kilopower fission systems can potentially save four to eight metric tons of landed mass, as compared to a single, large Fission Surface Power (FSP) concept. Breaking the power system up into modular packages creates new operational opportunities, with benefits ranging from reduced lander self-sufficiency for power, to extending the exploration distance from a single landing site. Although a large FSP trades well for operational complexity, a modular approach potentially allows Program Managers more flexibility to absorb late mission changes with less schedule or mass risk, better supports small precursor missions, and allows a program to slowly build up mission capability over time. A number of Kilopower disadvantages-and mitigation strategies-were also explored.

  15. Deploying the NASA Meter Class Autonomous Telescope (MCAT) on Ascension Island

    NASA Technical Reports Server (NTRS)

    Lederer, S. M.; Pace, L.; Hickson, P.; Cowardin, H. M.; Frith, J.; Buckalew, B.; Glesne, T.; Maeda, R.; Douglas, D.; Nishimoto, D.

    2015-01-01

    NASA has successfully constructed the 1.3m Meter Class Autonomous Telescope (MCAT) facility on Ascension Island in the South Atlantic Ocean. MCAT is an optical telescope designed specifically to collect ground-based data for the statistical characterization of orbital debris ranging from Low Earth Orbit (LEO) through Middle Earth Orbits (MEO) and beyond to Geo Transfer and Geosynchronous Orbits (GTO/GEO). The location of Ascension Island has two distinct advantages. First, the near-equatorial location fills a significant longitudinal gap in the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) network of telescopes, and second, it allows access to objects in Low Inclination Low-Earth Orbits (LILO). The MCAT facility will be controlled by a sophisticated software suite that operates the dome and telescope, assesses sky and weather conditions, conducts all necessary calibrations, defines an observing strategy (as dictated by weather, sky conditions and the observing plan for the night), and carries out the observations. It then reduces the collected data via four primary observing modes ranging from tracking previously cataloged objects to conducting general surveys for detecting uncorrelated debris. Nightly observing plans, as well as the resulting text file of reduced data, will be transferred to and from Ascension, respectively, via a satellite connection. Post-processing occurs at NASA Johnson Space Center. Construction began in September, 2014 with dome and telescope installation occurring in April through early June, 2015. First light was achieved in June, 2015. Acceptance testing, full commissioning, and calibration of this soon-to-be fully autonomous system commenced in summer 2015. The initial characterization of the system from these tests is presented herein.

  16. Deploying the NASA Meter Class Autonomous Telescope (MCAT) on Ascension Island

    NASA Astrophysics Data System (ADS)

    Lederer, S.; Pace, L. F.; Hickson, P.; Glesne, T.; Cowardin, H. M.; Frith, J. M.; Buckalew, B.; Maeda, R.; Douglas, D.; Nishimoto, D.

    NASA has successfully constructed the 1.3m Meter Class Autonomous Telescope (MCAT) facility on Ascension Island in the South Atlantic Ocean. MCAT is an optical telescope designed specifically to collect ground-based data for the statistical characterization of orbital debris ranging from Low Earth Orbit (LEO) through Middle Earth Orbits (MEO) and beyond to Geo Transfer and Geosynchronous Orbits (GTO/GEO). The location of Ascension Island has two distinct advantages. First, the near-equatorial location fills a significant longitudinal gap in the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) network of telescopes, and second, it allows access to objects in Low Inclination Low-Earth Orbits (LILO). The MCAT facility will be controlled by a sophisticated software suite that operates the dome and telescope, assesses sky and weather conditions, conducts all necessary calibrations, defines an observing strategy (as dictated by weather, sky conditions, and the observing plan for the night), and carries out the observations. It then reduces the collected data via four primary observing modes ranging from tracking previously cataloged objects to conducting general surveys for detecting uncorrelated debris. Nightly observing plans, as well as the resulting text file of reduced data, will be transferred to and from Ascension, respectively, via a satellite connection. Post-processing occurs at NASA Johnson Space Center. Construction began in September, 2014 with dome and telescope installation occurring in April through early June, 2015. First light was achieved in June, 2015. Acceptance testing, full commissioning, and calibration of this soon-to-be fully autonomous system commenced in summer 2015. The initial characterization of the system from these tests is presented herein.

  17. Geomorphology of Two Seamounts Offshore Ascension Island, South Atlantic Ocean

    DTIC Science & Technology

    2003-09-01

    comprise a transitional to mildly alkaline basalt -hawiite- mugearite-benmoreite-trachyte-rhyolite series lava flows, trachytic domes, scoria cones...age from 1.2 Ma to 0.56 Ma, mafic volcanic rocks range from 0.47 Ma to 0.12 Ma, and basaltic dikes are 0.80 Ma [11]. There have been no historic...hundred million years [28]. The isotopic combinations for Ascension Island are also significantly distinct from MAR basalt samples and 40

  18. Having faith in each other: not-for-profit giant Ascension Health hooks up with United Surgical Partners for ASC joint venture.

    PubMed

    Romano, Michael

    2004-09-13

    In the biggest deal of its kind, not-for-profit giant Ascension is going to build ambulatory surgery centers with for-profit United Surgical Partners, which already has a deal with Baylor, left. "Hospitals are realizing that outpatient services are the future. This strategy is sound," one healthcare consultant said.

  19. Powering nanorobotic devices: challenges and future strategies

    NASA Astrophysics Data System (ADS)

    Sankar, Krishna Moorthi

    2014-04-01

    Nanotechnology, even after 55 years since its foundation (1959 Richard Feynman's speech - `There is lot of space in the bottom'), is still in its infancy. However, of late, there has been a large increase in the research being done in this field in many prominent Universities and Research institutions across the globe. Nanorobotics is the combination of Nanotechnology and the science of Robotics, to create robots that are only a few nanometres (10-9 metres) in size. Nanobots are yet to be made. But with the current pace of ongoing researches, scientists predict that nanobots will be made a reality by next ten years. The main proposed function of nanobots is to use them in the medical field to interact with cells or intra-cellular substances and prevent or reverse structural and genetical problems and diseases. One of the major challenges faced while creating a nanobot to travel through human body is to power it. Nanobots would require a very small yet highly potential source of energy. There are many hypothesised energy sources for nanobots which are either already available within the human body naturally or which are to be supplied externally. But, all of these energy sources pose a few challenges which need to be addressed if they are to be used to power nanobots. These challenges can be overcome using a number of strategies that can be used to make an economically, ecologically and medically viable energy source.

  20. Experimentally Determined Coordinates for Three MILS Hydrophones Near Ascension Island

    SciTech Connect

    Harben, P. E.; Hollfelder, J. R.; Rodgers, A. J.

    1999-11-19

    We conducted an airgun survey in the waters of Ascension Island in May 1999 to determine new locations and depths for three Missile Impact Location System (MILS) hydrophones (ASC23, ASC24, and ASC26) currently in use by the Prototype International Data Center (PIDC) and the National Data Center (NDC). The nominal and new locations are summarized in Table 1. Although not rigorous, errors in the new locations and depths are conservatively estimated to be less than 100 m. The hydrophones are either on or near the ocean bottom in all three cases. The new depths are consistent with the following: Direct-phase airgun arrivals; Bathymetry determined along the track of the ship used for this airgun survey; Reflected phases from the airgun data; and Depths given in the original hydrophone installation report.

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

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

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

  2. Atmospheric Sampling on Ascension Island Using Multirotor UAVs.

    PubMed

    Greatwood, Colin; Richardson, Thomas S; Freer, Jim; Thomas, Rick M; MacKenzie, A Rob; Brownlow, Rebecca; Lowry, David; Fisher, Rebecca E; Nisbet, Euan G

    2017-05-23

    As part of an NERC-funded project investigating the southern methane anomaly, a team drawn from the Universities of Bristol, Birmingham and Royal Holloway flew small unmanned multirotors from Ascension Island for the purposes of atmospheric sampling. The objective of these flights was to collect air samples from below, within and above a persistent atmospheric feature, the Trade Wind Inversion, in order to characterise methane concentrations and their isotopic composition. These parameters allow the methane in the different air masses to be tied to different source locations, which can be further analysed using back trajectory atmospheric computer modelling. This paper describes the campaigns as a whole including the design of the bespoke eight rotor aircraft and the operational requirements that were needed in order to collect targeted multiple air samples up to 2.5 km above the ground level in under 20 min of flight time. Key features of the system described include real-time feedback of temperature and humidity, as well as system health data. This enabled detailed targeting of the air sampling design to be realised and planned during the flight mission on the downward leg, a capability that is invaluable in the presence of uncertainty in the pre-flight meteorological data. Environmental considerations are also outlined together with the flight plans that were created in order to rapidly fly vertical transects of the atmosphere whilst encountering changing wind conditions. Two sampling campaigns were carried out in September 2014 and July 2015 with over one hundred high altitude sampling missions. Lessons learned are given throughout, including those associated with operating in the testing environment encountered on Ascension Island.

  3. Atmospheric Sampling on Ascension Island Using Multirotor UAVs

    PubMed Central

    Greatwood, Colin; Richardson, Thomas S.; Freer, Jim; Thomas, Rick M.; MacKenzie, A. Rob; Brownlow, Rebecca; Lowry, David; Fisher, Rebecca E.; Nisbet, Euan G.

    2017-01-01

    As part of an NERC-funded project investigating the southern methane anomaly, a team drawn from the Universities of Bristol, Birmingham and Royal Holloway flew small unmanned multirotors from Ascension Island for the purposes of atmospheric sampling. The objective of these flights was to collect air samples from below, within and above a persistent atmospheric feature, the Trade Wind Inversion, in order to characterise methane concentrations and their isotopic composition. These parameters allow the methane in the different air masses to be tied to different source locations, which can be further analysed using back trajectory atmospheric computer modelling. This paper describes the campaigns as a whole including the design of the bespoke eight rotor aircraft and the operational requirements that were needed in order to collect targeted multiple air samples up to 2.5 km above the ground level in under 20 min of flight time. Key features of the system described include real-time feedback of temperature and humidity, as well as system health data. This enabled detailed targeting of the air sampling design to be realised and planned during the flight mission on the downward leg, a capability that is invaluable in the presence of uncertainty in the pre-flight meteorological data. Environmental considerations are also outlined together with the flight plans that were created in order to rapidly fly vertical transects of the atmosphere whilst encountering changing wind conditions. Two sampling campaigns were carried out in September 2014 and July 2015 with over one hundred high altitude sampling missions. Lessons learned are given throughout, including those associated with operating in the testing environment encountered on Ascension Island. PMID:28545231

  4. The NASA Meter Class Autonomous Telescope: Ascension Island

    NASA Technical Reports Server (NTRS)

    Lederer, S. M.; Stansbery, E. G.; Cowardin, H. M.; Kervin, P.; Hickson, P.

    2013-01-01

    smaller in size, has been operating in conjunction with this effort until recently in M.ron, Spain. With the M.ron site closing, a significant gap in longitude exists between the New Mexico and Diego Garcia sites. This longitudinal gap is well covered by placing a telescope on Ascension Island (7degrees 58'20" S, 14degrees 24'4"W), in the Atlantic Ocean. Ascension Island offers the benefits of both location and weather. The near equatorial location affords the opportunity to access under-sampled low-inclination orbits and new GEO longitudes, while simultaneously filling in the GEODSS longitudinal gap. Ascension Island is a volcanic, desert island, receiving only 7" of rain per year on average. With consistent trade winds blowing from the SSE direction off Africa, the combination of an island location with consistent winds will create the smooth laminar flow sought after by all astronomical sites, which creates stable atmospheric ('seeing') conditions. Finally, this low population island has minimal lighting, resulting in very dark skies, ideal for an observatory.

  5. The NASA Meter Class Autonomous Telescope: Ascension Island

    NASA Astrophysics Data System (ADS)

    Lederer, S.; Stansbery, E. G.; Cowardin, H. M.; Kervin, P.; Hickson, P.

    2013-09-01

    smaller in size, has been operating in conjunction with this effort until recently in M?ron, Spain. With the M?ron site closing, a significant gap in longitude exists between the New Mexico and Diego Garcia sites. This longitudinal gap is well covered by placing a telescope on Ascension Island (7deg 58' 20" S, 14deg 24' 4"W), in the Atlantic Ocean. Ascension Island offers the benefits of both location and weather. The near equatorial location affords the opportunity to access under-sampled low-inclination orbits and new GEO longitudes, while simultaneously filling in the GEODSS longitudinal gap. Ascension Island is a volcanic, desert island, receiving only 7" of rain per year on average. With consistent trade winds blowing from the SSE direction off Africa, the combination of an island location with consistent winds will create the smooth laminar flow sought after by all astronomical sites, which creates stable atmospheric (‘seeing') conditions. Finally, this low population island has minimal lighting, resulting in very dark skies, ideal for an observatory.

  6. The NASA Meter Class Autonomous Telescope: Ascension Island

    NASA Technical Reports Server (NTRS)

    Lederer, S. M.; Stansbery, E. G.; Cowardin, H. M.; Hickson, P.; Pace, L. F.; Abercromby, K. J.; Kervin, P. W.

    2013-01-01

    The Meter Class Autonomous Telescope (MCAT) is the newest optical sensor dedicated to NASA's mission to characterize the space debris environment. It is the successor to a series of optical telescopes developed and operated by the JSC Orbital Debris Program Office (ODPO) to monitor and assess the debris environment in (1) Low Earth Orbit (LEO), (2) Medium Earth Orbit (MEO), and (3) Geosynchronous Orbit (GEO), with emphasis on LEO and GEO altitudes. A joint NASA - Air Force Research Labs project, MCAT is a 1.3m optical telescope dedicated to debris research. Its optical path and sensor yield a large survey fence at the cutting edge of current detector performance. It has four primary operational observing modes, two of which were not computationally feasible a decade ago. Operations are supported by a sophisticated software suite that monitors clouds and weather conditions, and controls everything from data collection to dome rotation to processing tens of gigabytes of image data nightly. With fainter detection limits, precision detection, acquisition and tracking of targets, multi-color photometry, precision astrometry, automated re-acquisition capability, and the ability to process all data at the acquisition rate, MCAT is capable of producing and processing a volume and quality of data far in excess of any current (or prior) ODPO operations. This means higher fidelity population inputs and eliminating the multi-year backlog from acquisition-to-product typical of optical campaigns. All of this is possible given a suitable observing location. Ascension Island offers numerous advantages. As a British overseas territory with a US Air Force base presence, the necessary infrastructure and support already exists. It is located mid-way between Brazil and Africa at 7.93S latitude and 14.37 W longitude. With the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) asset in Moron, Spain shutting down, this presents access to the sky from a unique latitude

  7. Power and Energy Strategy White Paper

    DTIC Science & Technology

    2010-04-01

    any sulfur, which can “poison” the cell; • Power density for an integrated fuel cell system is generally lower than an internal combustion engine ...The Army must integrate electrical power systems and grids, including component design (e.g., controls, switching and storage). The multi-energy...Development and integration of wireless transmission for select applications 17 AERIAL VEHICLE POWER Army aviation, manned and unmanned, is

  8. Power optimal single-axis articulating strategies

    NASA Technical Reports Server (NTRS)

    Kumar, Renjith R.; Heck, Michael L.

    1991-01-01

    Power optimal single axis articulating PV array motion for Space Station Freedom is investigated. The motivation is to eliminate one of the articular joints to reduce Station costs. Optimal (maximum power) Beta tracking is addressed for local vertical local horizontal (LVLH) and non-LVLH attitudes. Effects of intra-array shadowing are also presented. Maximum power availability while Beta tracking is compared to full sun tracking and optimal alpha tracking. The results are quantified in orbital and yearly minimum, maximum, and average values of power availability.

  9. An evolutionary strategy for space nuclear power

    SciTech Connect

    Bennett, G.L.

    1996-03-01

    A number of exciting mission opportunities are being considered for the 21st century, including (1) advanced robotic science missions to the outer planets and beyond; (2) advanced space transportation systems; and (3) human exploration of the Moon and Mars. Several of these missions will require some form of nuclear power; however, it is clear that current budgetary constraints preclude developing many different types of space nuclear power systems. This paper reviews the specific civil space missions which have been identified, the power levels and lifetimes required, and the technologies available. From this an evolutionary space nuclear power program is developed which builds upon the experience of radioisotope thermoelectric generators, improved static and dynamic isotope power systems, and space nuclear reactors. It is strongly suggested that not only does this approach make technical and budgetary sense but that it is consistent with the normal development of new technologies. {copyright} {ital 1996 American Institute of Physics.}

  10. Constructing Cultures of Non-Violence: The Peace Power! Strategy.

    ERIC Educational Resources Information Center

    Mattaini, Mark A.; Addams, Jane

    2001-01-01

    This article presents an alternative approach for reducing violence in schools: the development of evidence-based tools that can be used in existing networks to structure systemic changes. The PEACE POWER strategy emphasizes four practices: recognize contributions and successes, act with respect, share power to build community, and make peace.…

  11. Constructing Cultures of Non-Violence: The Peace Power! Strategy.

    ERIC Educational Resources Information Center

    Mattaini, Mark A.; Addams, Jane

    2001-01-01

    This article presents an alternative approach for reducing violence in schools: the development of evidence-based tools that can be used in existing networks to structure systemic changes. The PEACE POWER strategy emphasizes four practices: recognize contributions and successes, act with respect, share power to build community, and make peace.…

  12. Power Strategies: Determinants in Marital and Professional Relationships.

    ERIC Educational Resources Information Center

    Weltman, Karen; Steil, Janice

    Power and influence are fundamental determinants of the direction and quality of interpersonal relationships. Research has shown that women tend to have less power than men in their intimate and professional relationships and that men are more likely than women to use direct strategies to achieve their goals. A study was conducted to investigate…

  13. New power strategies (the battle for control).

    PubMed

    Solovy, A

    1994-12-20

    When yesterday's home care company has become today's primary care network, and yesterday's purchaser is today's provider, it's no longer enough to look at hospital/physician integration for clues to the new health care road map. Instead, it's vital to examine how all the players in the health care system are interacting, and what the interchanges of power and activity among them mean. In a probing analysis, Contributing Editor Alden Solovy applies an innovative macroeconomic theory to the radical reshaping of health care now taking place.

  14. Strategies in tower solar power plant optimization

    NASA Astrophysics Data System (ADS)

    Ramos, A.; Ramos, F.

    2012-09-01

    A method for optimizing a central receiver solar thermal electric power plant is studied. We parametrize the plant design as a function of eleven design variables and reduce the problem of finding optimal designs to the numerical problem of finding the minimum of a function of several variables. This minimization problem is attacked with different algorithms both local and global in nature. We find that all algorithms find the same minimum of the objective function. The performance of each of the algorithms and the resulting designs are studied for two typical cases. We describe a method to evaluate the impact of design variables in the plant performance. This method will tell us what variables are key to the optimal plant design and which ones are less important. This information can be used to further improve the plant design and to accelerate the optimization procedure.

  15. Optimal generator bidding strategies for power and ancillary services

    NASA Astrophysics Data System (ADS)

    Morinec, Allen G.

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

  16. An evolution strategy for lunar nuclear surface power

    NASA Technical Reports Server (NTRS)

    Mason, Lee S.

    1992-01-01

    The production and transmission of electric power for a permanently inhabited lunar base poses a significant challenge which can best be met through an evolution strategy. Nuclear systems offer the best opportunity for evolution in terms of both life and performance. Applicable nuclear power technology options include isotope systems (either radioisotope thermoelectric generators or dynamic isotope power systems) and reactor systems with either static (thermoelectric or thermionic) or dynamic (Brayton, Stirling, Rankine) conversion. A power system integration approach that takes evolution into account would benefit by reduced development and operations cost, progressive flight experience, and simplified logistics, and would permit unrestrained base expansion. For the purposes of defining a nuclear power system evolution strategy, the lunar base development shall consist of four phases: precursor, emplacement, consolidation, and operations.

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

    NASA Astrophysics Data System (ADS)

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

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

  18. Reactive power optimization strategy considering analytical impedance ratio

    NASA Astrophysics Data System (ADS)

    Wu, Zhongchao; Shen, Weibing; Liu, Jinming; Guo, Maoran; Zhang, Shoulin; Xu, Keqiang; Wang, Wanjun; Sui, Jinlong

    2017-05-01

    In this paper, considering the traditional reactive power optimization cannot realize the continuous voltage adjustment and voltage stability, a dynamic reactive power optimization strategy is proposed in order to achieve both the minimization of network loss and high voltage stability with wind power. Due to the fact that wind power generation is fluctuant and uncertain, electrical equipments such as transformers and shunt capacitors may be operated frequently in order to achieve minimization of network loss, which affect the lives of these devices. In order to solve this problem, this paper introduces the derivation process of analytical impedance ratio based on Thevenin equivalent. Thus, the multiple objective function is proposed to minimize the network loss and analytical impedance ratio. Finally, taking the improved IEEE 33-bus distribution system as example, the result shows that the movement of voltage control equipment has been reduced and network loss increment is controlled at the same time, which proves the applicable value of this strategy.

  19. Whither Space Power? Forging a Strategy for the New Century

    DTIC Science & Technology

    2002-09-01

    order, two more recent events may serve as cat­ alysts for the development of an effective US national security space strategy and policy. The first... event was the publication, in January 2001, of the report of the Commission to Assess United States National Security Space Management and Orga­...effectively, and facilitate the development of a comprehensive space power strategy. The second event was the act of war inflicted upon the United States

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

    ERIC Educational Resources Information Center

    Olekalns, Mara; Smith, Philip Leigh

    2013-01-01

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

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

    ERIC Educational Resources Information Center

    Olekalns, Mara; Smith, Philip Leigh

    2013-01-01

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

  2. Model predictive control power management strategies for HEVs: A review

    NASA Astrophysics Data System (ADS)

    Huang, Yanjun; Wang, Hong; Khajepour, Amir; He, Hongwen; Ji, Jie

    2017-02-01

    This paper presents a comprehensive review of power management strategy (PMS) utilized in hybrid electric vehicles (HEVs) with an emphasis on model predictive control (MPC) based strategies for the first time. Research on MPC-based power management systems for HEVs has intensified recently due to its many inherent merits. The categories of the existing PMSs are identified from the latest literature, and a brief study of each type is conducted. Then, the MPC approach is introduced and its advantages are discussed. Based on the acquisition method of driver behavior used for state prediction and the dynamic model used, the MPC is classified and elaborated. Factors that affect the performance of the MPC are put forward, including prediction accuracy, design parameters, and solvers. Finally, several important issues in the application of MPC-based power management strategies and latest developing trends are discussed. This paper not only provides a comprehensive analysis of MPC-based power management strategies for HEVs but also puts forward the future and emphasis of future study, which will promote the development of energy management controller with high performance and low cost for HEVs.

  3. Peace Power for Adolescents: Strategies for a Culture of Nonviolence.

    ERIC Educational Resources Information Center

    Mattaini, Mark A.

    Recent school shootings are only one symptom of a greater problem--a toxic social environment that breeds isolation and rage among children. This book looks at the wide range of risk factors and indicators for violence and translates the findings into an effective prevention and intervention system. The Peace Power strategy is based on four core…

  4. Peace Power for Adolescents: Strategies for a Culture of Nonviolence.

    ERIC Educational Resources Information Center

    Mattaini, Mark A.

    Recent school shootings are only one symptom of a greater problem--a toxic social environment that breeds isolation and rage among children. This book looks at the wide range of risk factors and indicators for violence and translates the findings into an effective prevention and intervention system. The Peace Power strategy is based on four core…

  5. Radioisotope-based Nuclear Power Strategy for Exploration Systems Development

    SciTech Connect

    Schmidt, George R.; Houts, Michael G.

    2006-01-20

    Nuclear power will play an important role in future exploration efforts. Its benefits pertain to practically all the different timeframes associated with the Exploration Vision, from robotic investigation of potential lunar landing sites to long-duration crewed missions on the lunar surface. However, the implementation of nuclear technology must follow a logical progression in capability that meets but does not overwhelm the power requirements for the missions in each exploration timeframe. It is likely that the surface power infrastructure, particularly for early missions, will be distributed in nature. Thus, nuclear sources will have to operate in concert with other types of power and energy storage systems, and must mesh well with the power architectures envisioned for each mission phase. Most importantly, they must demonstrate a clear advantage over other non-nuclear options (e.g., solar power, fuel cells) for their particular function. This paper describes a strategy that does this in the form of three sequential system developments. It begins with use of radioisotope generators currently under development, and applies the power conversion technology developed for these units to the design of a simple, robust reactor power system. The products from these development efforts would eventually serve as the foundation for application of nuclear power systems for exploration of Mars and beyond.

  6. Operational and design strategies to improve PFBC power plant efficiency

    SciTech Connect

    Romeo, L.M.; Cortes, C.; Martinez, D.

    1998-07-01

    Nowadays the state of the art of PFBC technology lies halfway between the demonstration stage in units of intermediate size (72--79 MWe) and the commercial availability of larger scale plants. The operation of existing power stations has demonstrated that several points remain widely open to improvements. Due to fuel quality effects and the use of retrofitted plants, the PFBC power plant efficiency presently demands significant improvements. Likewise, the high energy efficiencies offered by the PFBC concept had not been completely demonstrated. To overcome these difficulties and further develop the technology a semiempirical model of a pressurized fluidized bed power plant has been developed. The model has been validated with actual plant data, being able to predict the Escatron (Spain) PFBC power plant behavior under different operating conditions. It has been widely tested to study not only the fluidized bed behavior, but also the influence of fluidized bed variables in the rest of the power plant. Good agreement has been found between the computed results and actual plant data at different operational regimes for the most important variables of the power plant. The main aim of this model is to study different strategies to improve the efficiency in the power plant. These strategies include: the improvement of soot blowing schedules of external heat exchangers; air preheating system optimization; selection of operational set-points that bring the highest efficiency; evaluation of the efficiency improvements due to design changes (changes in retrofitted steam turbines and heat exchangers, natural gas reburning, selection of different types of coal). This paper describes the model developed, the strategies to improve efficiency, as well as its results, and as conclusions, point out the improvements and perspectives for future work.

  7. Synergistic Catalysis: A Powerful Synthetic Strategy for New Reaction Development

    PubMed Central

    Allen, Anna E.; MacMillan, David W. C.

    2012-01-01

    Synergistic catalysis is a synthetic strategy wherein both the nucleophile and the electrophile are simultaneously activated by two separate and distinct catalysts to afford a single chemical transformation. This powerful catalysis strategy leads to several benefits, specifically synergistic catalysis can (i) introduce new, previously unattainable chemical transformations, (ii) improve the efficiency of existing transformations, and (iii) create or improve catalytic enantioselectivity where stereocontrol was previously absent or challenging. This perspective aims to highlight these benefits using many of the successful examples of synergistic catalysis found in the literature. PMID:22518271

  8. Strategies for Radiation Hardness Testing of Power Semiconductor Devices

    NASA Technical Reports Server (NTRS)

    Soltis, James V. (Technical Monitor); Patton, Martin O.; Harris, Richard D.; Rohal, Robert G.; Blue, Thomas E.; Kauffman, Andrew C.; Frasca, Albert J.

    2005-01-01

    Plans on the drawing board for future space missions call for much larger power systems than have been flown in the past. These systems would employ much higher voltages and currents to enable more powerful electric propulsion engines and other improvements on what will also be much larger spacecraft. Long term human outposts on the moon and planets would also require high voltage, high current and long life power sources. Only hundreds of watts are produced and controlled on a typical robotic exploration spacecraft today. Megawatt systems are required for tomorrow. Semiconductor devices used to control and convert electrical energy in large space power systems will be exposed to electromagnetic and particle radiation of many types, depending on the trajectory and duration of the mission and on the power source. It is necessary to understand the often very different effects of the radiations on the control and conversion systems. Power semiconductor test strategies that we have developed and employed will be presented, along with selected results. The early results that we have obtained in testing large power semiconductor devices give a good indication of the degradation in electrical performance that can be expected in response to a given dose. We are also able to highlight differences in radiation hardness that may be device or material specific.

  9. Maximum wind energy extraction strategies using power electronic converters

    NASA Astrophysics Data System (ADS)

    Wang, Quincy Qing

    2003-10-01

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

  10. Isotope and methane dynamics above and below the Trade Wind Inversion at Ascension Island using UAVs

    NASA Astrophysics Data System (ADS)

    Brownlow, R.; Lowry, D.; Nisbet, E. G.; Fisher, R. E.; France, J.; Lanoisellé, M.; Thomas, R.; Richardson, T.; Greatwood, C.; Freer, J. E.; MacKenzie, A. R.

    2015-12-01

    Ascension Island (8oS, 14 oW) is a South Atlantic background site for atmospheric measurement. Royal Holloway, in collaboration with the UK Met Office, installed a Picarro 1301 CRDS in 2010 for continuous methane monitoring. This has high precision and accuracy, with a 6-gas calibration and target suite, to measure long term methane mole fraction. Regular flask sampling is also carried out for NOAA and RHUL (co-located), to measure δ13CCH4 isotopic trends.Ascension Island experiences near-constant SE Trade winds below the Trade Wind Inversion (TWI), with air from the remote S. Atlantic. In flask samples and in continuous monitoring at the Airhead location, atmospheric methane mole fraction has been increasing since 2007 whilst the δ13CCH4 isotope record has shifted to more depleted values. Above the normally well-defined TWI (1200 - 1800m altitude), variable tropical air masses pass over Ascension. This air last mixed with the boundary layer over Africa or South America. Field work undertaken in September 2014 and July 2015, in collaboration with U. Bristol and U. Birmingham, using UAVs (octocopters) collected samples with Tedlar bags or aluminium flasks from different heights above and below the TWI. The maximum altitude reached was 2700masl. Sample bags were immediately analysed on Ascension for CH4 mole fraction using the Picarro CRDS and subsequently analysed at RHUL for δ13CCH4 using continuous-flow gas chromatography/isotope-ratio mass spectrometry (CF-GC/IRMS). The TWI was clearly identified by an increase in CH4 mole fraction above the TWI. Back trajectory analysis was used to distinguish the origins of the air masses, with air above showing inputs from the land surfaces of equatorial and southern Africa, and from southern S. America.The campaigns have extended the envelope of altitudes accessed by micro-UAVs for atmospheric science, demonstrating their utility for probing the remote free troposphere and for penetrating the TWI. Sampling at Ascension is

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

    SciTech Connect

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

    2010-02-01

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

  12. Wake Mitigation Strategies for Optimizing Wind Farm Power Production

    NASA Astrophysics Data System (ADS)

    Dilip, Deepu; Porté-Agel, Fernando

    2016-04-01

    Although wind turbines are designed individually for optimum power production, they are often arranged into groups of closely spaced turbines in a wind farm rather than in isolation. Consequently, most turbines in a wind farm do not operate in unobstructed wind flows, but are affected by the wakes of turbines in front of them. Such wake interference significantly reduces the overall power generation from wind farms and hence, development of effective wake mitigation strategies is critical for improving wind farm efficiency. One approach towards this end is based on the notion that the operation of each turbine in a wind farm at its optimum efficiency might not lead to optimum power generation from the wind farm as a whole. This entails a down regulation of individual turbines from its optimum operating point, which can be achieved through different methods such as pitching the turbine blades, changing the turbine tip speed ratio or yawing of the turbine, to name a few. In this study, large-eddy simulations of a two-turbine arrangement with the second turbine fully in the wake of the first are performed. Different wake mitigation techniques are applied to the upstream turbine, and the effects of these on its wake characteristics are investigated. Results for the combined power from the two turbines for each of these methods are compared to a baseline scenario where no wake mitigation strategies are employed. Analysis of the results shows the potential for improved power production from such wake control methods. It should be noted, however, that the magnitude of the improvement is strongly affected by the level of turbulence in the incoming atmospheric flow.

  13. Isotopic composition of lead and strontium from Ascension and Gough Islands

    USGS Publications Warehouse

    Gast, P.W.; Tilton, G.R.; Hedge, C.

    1964-01-01

    Isotopic composition of lead and strontium has been determined in a series of rock samples from two islands on the Mid-Atlantic Ridge. Both inter-and intra-island variations exist in the abundance of radiogenic isotopes of both elements. Lead from basalt of Ascension Island has a Pb206-Pb 204 ratio of 19.5, while the corresponding ratio at Gough Island is only 18.4. The Pb208-Pb204 ratios from the two islands do not differ. Conversely, strontium from basalt of Ascension Island is less radiogenic than that from Gough Island basalts. The trachytes of both islands have lead and strontium that is more radiogenic than that found in the basalts. The inter-island differences indicate the existence of regional variations in the uranium-lead and rubidium-strontium ratios of the upper mantle source of these rocks and show that isotope compositions are a means for investigating chemical heterogeneities in the mantle.

  14. Ascension Island: a survey to assess the presence of Zika virus vectors.

    PubMed

    Bullivant, G; Martinou, A F

    2017-10-01

    Following concerns regarding the spread of Zika virus, Joint Services Health Unit (Cyprus) were tasked to carry out a mosquito survey on the Ascension Island, South Atlantic. This was to determine if vectors of the virus such as Aedes aegypti and Aedes albopictus were introduced and established on the Island. An extensive survey of residential areas and natural habitats was initiated in order to collect mosquito larvae and adults by methods such as larval sampling, adult trapping and human landing catches. A. aegypti or A. albopictus were not collected by any of the three methods employed. Culex quinquefasciatus was the only species collected by all three methods. C. quinquefasciatus is a vector of lymphatic filariasis that can easily be transported by human means by air or sea. It is a container breeding species that lives in close proximity to human settlements and can cause significant amount of nuisance. Ascension Island is connected by air and sea with areas of the world where container breeding species such as A. albopictus and A. aegypti are established, therefore, it is not unlikely that these species become introduced to Ascension in the future. Sound surveillance on Ascension is imperative in order to act as an early warning and rapid response system for invasive mosquito species as well as a guide for the implementation of control measures against C. quinquefasciatus. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  15. Nonvertical ascension or fall of a free sphere in a Newtonian fluid

    NASA Astrophysics Data System (ADS)

    Jenny, Mathieu; Bouchet, Gilles; Dušek, Jan

    2003-01-01

    It is shown that the system represented by a free sphere ascending or falling in a Newtonian fluid under the action of gravity buoyancy undergoes a regular, symmetry breaking bifurcation making the trajectory deviate from the vertical direction. The instability threshold expressed in terms of the asymptotic Reynolds number lies below that of a fixed sphere wake. The instability is shown to saturate and reach a fixed point corresponding to a straight oblique ascension (fall).

  16. Cultural Crisis? An Analysis of the Issues Affecting the Ascension of Women in the Australian Army

    DTIC Science & Technology

    2014-06-13

    appears to be an aversion to fully supporting the concept of work-life balance, a notion supported by the low percentage of personnel taking...to 2014. The analysis of Pathway to Change and FWA form the cornerstone of the concept of work-life balance, to determine if the Australian Army is... concept . The study’s principal aim is to identify the contributing factors impeding the ascension of women in the Australian Army. The study offers

  17. Abdicating power for control: a precision timing strategy to modulate function of flight power muscles.

    PubMed

    Sponberg, S; Daniel, T L

    2012-10-07

    Muscles driving rhythmic locomotion typically show strong dependence of power on the timing or phase of activation. This is particularly true in insects' main flight muscles, canonical examples of muscles thought to have a dedicated power function. However, in the moth (Manduca sexta), these muscles normally activate at a phase where the instantaneous slope of the power-phase curve is steep and well below maximum power. We provide four lines of evidence demonstrating that, contrary to the current paradigm, the moth's nervous system establishes significant control authority in these muscles through precise timing modulation: (i) left-right pairs of flight muscles normally fire precisely, within 0.5-0.6 ms of each other; (ii) during a yawing optomotor response, left-right muscle timing differences shift throughout a wider 8 ms timing window, enabling at least a 50 per cent left-right power differential; (iii) timing differences correlate with turning torque; and (iv) the downstroke power muscles alone causally account for 47 per cent of turning torque. To establish (iv), we altered muscle activation during intact behaviour by stimulating individual muscle potentials to impose left-right timing differences. Because many organisms also have muscles operating with high power-phase gains (Δ(power)/Δ(phase)), this motor control strategy may be ubiquitous in locomotor systems.

  18. The navigational feats of green sea turtles migrating from Ascension Island investigated by satellite telemetry.

    PubMed Central

    Luschi, P; Hays, G C; Del Seppia, C; Marsh, R; Papi, F

    1998-01-01

    Previous tagging studies of the movements of green turtles (Chelonia mydas) nesting at Ascension Island have shown that they shuttle between this remote target in the Atlantic Ocean and their feeding grounds on the Brazilian coast, a distance of 2300 km or more. Since a knowledge of sea turtle migration routes might allow inferences on the still unknown navigational mechanisms of marine animals, we tracked the postnesting migration of six green turtle females from Ascension Island to Brazil. Five of them reached the proximity of the easternmost stretch of the Brazilian coast, covering 1777-2342 km in 33-47 days. Their courses were impressively similar for the first 1000 km, with three turtles tracked over different dates following indistinguishable paths for the first 300 km. Only the sixth turtle made some relatively short trips in different directions around Ascension. The tracks show that turtles (i) are able to maintain straight courses over long distances in the open sea; (ii) may perform exploratory movements in different directions; (iii) appropriately correct their course during the journey according to external information; and (iv) initially keep the same direction as the west-south-westerly flowing current, possibly guided by chemical cues. PMID:9881473

  19. The genus Erechthias Meyrick of Ascension Island, including discovery of a new brachypterous species (Lepidoptera, Tineidae).

    PubMed

    Davis, Donald R; Mendel, Howard

    2013-01-01

    One previously named and two new species of the tineid genus Erechthias Meyrick are described and illustrated from the small, remote, mid-Atlantic Ascension Island. With these additions the Lepidoptera fauna of Ascension now totals 38 known species. Little is known regarding the biology of the two new species of Erechthias, and none of the species has been reared from larvae from Ascension. Erechthias minuscula (Walsingham) is a widespread, largely pantropical species first described from the West Indies. Larvae of Erechthias minuscula are known to be scavengers on a wide variety of dead plant material. Erechthias ascensionae,new species, is one of two species of Erechthias now known to be endemic to the island. The other endemic species, Erechthias grayi, new species, is further remarkable in having wing reduction occurring in both sexes. It is one of the few species of Lepidoptera known where this extreme of brachyptery involving both sexes has evolved. The larvae of Erechthias grayi are believed to be lichenivorous, and larval cases suspected to represent this species are illustrated.

  20. The genus Erechthias Meyrick of Ascension Island, including discovery of a new brachypterous species (Lepidoptera, Tineidae)

    PubMed Central

    Davis, Donald R.; Mendel, Howard

    2013-01-01

    Abstract One previously named and two new species of the tineid genus Erechthias Meyrick are described and illustrated from the small, remote, mid-Atlantic Ascension Island. With these additions the Lepidoptera fauna of Ascension now totals 38 known species. Little is known regarding the biology of the two new species of Erechthias, and none of the species has been reared from larvae from Ascension. Erechthias minuscula (Walsingham) is a widespread, largely pantropical species first described from the West Indies. Larvae of Erechthias minuscula are known to be scavengers on a wide variety of dead plant material. Erechthias ascensionae,new species, is one of two species of Erechthias now known to be endemic to the island. The other endemic species, Erechthias grayi, new species, is further remarkable in having wing reduction occurring in both sexes. It is one of the few species of Lepidoptera known where this extreme of brachyptery involving both sexes has evolved. The larvae of Erechthias grayi are believed to be lichenivorous, and larval cases suspected to represent this species are illustrated. PMID:24146595

  1. Recent sea beam mapping of Ascension-Monterey Submarine Canyon System

    SciTech Connect

    Greene, H.G. )

    1990-06-01

    Extensive Sea Beam and Bathymetric Swatch Survey System (BS{sup 3}) data covering the Ascension-Monterey Submarine Canyon system and adjoining areas and canyons were collected offshore central California. Many discovered geomorphological features lead to significant new geologic conclusions about the formation and processes of submarine canyons in general and disclose unique sedimentary and tectonic features of the Ascension-Monterey Canyon system. The highly detailed bathymetric maps constructed from the Sea Beam data indicate that the seafloor topographic pattern is influenced by sedimentary and tectonic processes; both remain active along the central California margin. Interpretations of MOAA composite maps, final raw Sea Beam bathymetric maps, and three-dimensional physiographic renditions from bathymetric data indicate a diverse and complex geomorphology for the Ascension-Monterey Submarine Canyon system and adjoining region. Five distinct geomorphologic provinces and four well-defined geographic areas are mapped. Canyons cut by faults and canyon walls actively undergoing mass wasting are prominently displayed in the Sea Beam data. Sedimentary processes illustrating canyon channel capture and the formation of extensive mega-sedimentary wave fields where the canyons debouch onto the abyssal plain are spectacularly well defined. This new tool of seafloor mapping is contributing significant data for the geological interpretation of continental margins and seafloor in the world's oceans.

  2. 77 FR 28871 - Renewable Power Strategies, LLC; Supplemental Notice That Initial Market-Based Rate Filing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Renewable Power Strategies, LLC; Supplemental Notice That Initial Market... in the above-referenced proceeding of Renewable Power Strategies, LLC's application for...

  3. Fault Diagnosis Strategies for SOFC-Based Power Generation Plants.

    PubMed

    Costamagna, Paola; De Giorgi, Andrea; Gotelli, Alberto; Magistri, Loredana; Moser, Gabriele; Sciaccaluga, Emanuele; Trucco, Andrea

    2016-08-22

    The success of distributed power generation by plants based on solid oxide fuel cells (SOFCs) is hindered by reliability problems that can be mitigated through an effective fault detection and isolation (FDI) system. However, the numerous operating conditions under which such plants can operate and the random size of the possible faults make identifying damaged plant components starting from the physical variables measured in the plant very difficult. In this context, we assess two classical FDI strategies (model-based with fault signature matrix and data-driven with statistical classification) and the combination of them. For this assessment, a quantitative model of the SOFC-based plant, which is able to simulate regular and faulty conditions, is used. Moreover, a hybrid approach based on the random forest (RF) classification method is introduced to address the discrimination of regular and faulty situations due to its practical advantages. Working with a common dataset, the FDI performances obtained using the aforementioned strategies, with different sets of monitored variables, are observed and compared. We conclude that the hybrid FDI strategy, realized by combining a model-based scheme with a statistical classifier, outperforms the other strategies. In addition, the inclusion of two physical variables that should be measured inside the SOFCs can significantly improve the FDI performance, despite the actual difficulty in performing such measurements.

  4. Fault Diagnosis Strategies for SOFC-Based Power Generation Plants

    PubMed Central

    Costamagna, Paola; De Giorgi, Andrea; Gotelli, Alberto; Magistri, Loredana; Moser, Gabriele; Sciaccaluga, Emanuele; Trucco, Andrea

    2016-01-01

    The success of distributed power generation by plants based on solid oxide fuel cells (SOFCs) is hindered by reliability problems that can be mitigated through an effective fault detection and isolation (FDI) system. However, the numerous operating conditions under which such plants can operate and the random size of the possible faults make identifying damaged plant components starting from the physical variables measured in the plant very difficult. In this context, we assess two classical FDI strategies (model-based with fault signature matrix and data-driven with statistical classification) and the combination of them. For this assessment, a quantitative model of the SOFC-based plant, which is able to simulate regular and faulty conditions, is used. Moreover, a hybrid approach based on the random forest (RF) classification method is introduced to address the discrimination of regular and faulty situations due to its practical advantages. Working with a common dataset, the FDI performances obtained using the aforementioned strategies, with different sets of monitored variables, are observed and compared. We conclude that the hybrid FDI strategy, realized by combining a model-based scheme with a statistical classifier, outperforms the other strategies. In addition, the inclusion of two physical variables that should be measured inside the SOFCs can significantly improve the FDI performance, despite the actual difficulty in performing such measurements. PMID:27556472

  5. Compliance strategy in national thermal power corporation, India

    SciTech Connect

    Basu, B.; Rao, M.H.

    1998-07-01

    Established in the mid-seventies the National Thermal Power Corporation (NTPC) is now the largest power producing company in India with an installed capacity of more than 16,000 MW. The environmental impacts associated with thermal power generation are inviting greater attention in the country. Power generation, a vital input for industrial development has to grow but at the same time emphasis on mitigation of environmental impact associated with thermal power generation can not be undermined. The Regulatory Agencies in the country are also enacting several environmental laws progressively to ensure that the industrial development is sustainable. The growing concern of Regulatory Agencies is evident from the Environmental Clearance accorded by them for power plants. As against simple conditions stipulated in clearances for projects in the late seventies the current regulatory clearances address specific protective actions in almost all areas of environment like air, water, noise, ecology etc. Compliance by utilities to environmental laws and requirements of the Regulatory Agencies is a major step toward sustainable development. At the NTPC Stations apart from compliance there is emphasis on data generation through scientific studies on different aspects of ecosystem where information are scanty or ground truth is to be established, adoption of eco-friendly measures like re-use and recycling where feasible for optimization of requirement of plant, schemes for treatments of effluents etc. to ensure enhanced performance and adoption of comprehensive environmental management program with a view to identify critical parameters and take timely corrective action. The paper underscores the concern of NTPC toward environmental protection. Compliance strategies vis a vis the environmental laws and requirements of Regulatory Agencies have been discussed.

  6. The Acceptance Strategy for Nuclear Power Plant In Indonesia

    NASA Astrophysics Data System (ADS)

    Suhaemi, Tjipta; Syaukat, Achmad

    2010-06-01

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

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

    DTIC Science & Technology

    2016-06-01

    capabilities. A novel control strategy was also implemented to decrease the need for backup electrical power. The control strategy matches load...novel control strategy was also implemented to decrease the need for backup electrical power. The control strategy matches load demand from a chiller...65 Figure 36. Energy Paths for Electrical and Thermal Storage Devices ........................66 xi LIST OF TABLES Table

  8. Abdicating power for control: a precision timing strategy to modulate function of flight power muscles

    PubMed Central

    Sponberg, S.; Daniel, T. L.

    2012-01-01

    Muscles driving rhythmic locomotion typically show strong dependence of power on the timing or phase of activation. This is particularly true in insects' main flight muscles, canonical examples of muscles thought to have a dedicated power function. However, in the moth (Manduca sexta), these muscles normally activate at a phase where the instantaneous slope of the power–phase curve is steep and well below maximum power. We provide four lines of evidence demonstrating that, contrary to the current paradigm, the moth's nervous system establishes significant control authority in these muscles through precise timing modulation: (i) left–right pairs of flight muscles normally fire precisely, within 0.5–0.6 ms of each other; (ii) during a yawing optomotor response, left—right muscle timing differences shift throughout a wider 8 ms timing window, enabling at least a 50 per cent left–right power differential; (iii) timing differences correlate with turning torque; and (iv) the downstroke power muscles alone causally account for 47 per cent of turning torque. To establish (iv), we altered muscle activation during intact behaviour by stimulating individual muscle potentials to impose left—right timing differences. Because many organisms also have muscles operating with high power–phase gains (Δpower/Δphase), this motor control strategy may be ubiquitous in locomotor systems. PMID:22833272

  9. T-Phase Observations from the May 1999 Ascension Island Experiment

    SciTech Connect

    Rodgers, A; Harben, P

    2000-07-19

    The Comprehensive Nuclear-Test-Ban Treaty (CTBT) specifies that an International Monitoring System (IMS) will be used to detect and locate disturbances that could be related to nuclear testing. In order to monitor disturbances in and near the world's oceans, the IMS will rely on a network of 11 hydroacoustic stations. This hydroacoustic network will be composed of 6 hydrophone stations and 5 T-phase seismic stations. The hydrophone stations will record pressure variations in the ocean. The T-phase stations will record the seismic waves in the solid earth that are excited when an hydroacoustic wave strikes an island or continental margin. The coupling of hydroacoustic-to-seismic energy for the purpose of CTBT monitoring is currently an active area of research. We report observations of hydroacoustic waves and their conversion to seismic waves (T-waves) at the volcanic edifice of Ascension Island. Earthquakes to the south of Ascension Island were recorded by International Monitoring System hydrophones and temporary seismic stations deployed on Ascension Island by LLNL. The hydrophone recordings are rich in high frequency (10-40 Hz) energy. However, the converted seismic waves (T-waves) are dominated by much lower frequencies (2-8 Hz). The T-waves demonstrate amplitude and travel time variations on the Island. We performed two-dimensional finite difference simulations to determine if the amplitude variability is the result of conversion along the complex bathymetry of the island and subsequent propagation to the station or a site effect. These observations suggest that the T-phase stations of the IMS may be useful for detecting and locating events in support of the CTBT provided that T-phase travel times are appropriately calibrated. However on volcanic islands, event identification based on T-phase data, which relies on high frequencies, may be inhibited by strong attenuation and low signal-to-noise.

  10. Cosmogenic He-3 exposure ages of basalts from Ascension Island - implications for evolution of ocean islands

    NASA Astrophysics Data System (ADS)

    Ammon, K.; Dunai, T. J.; Stuart, F. M.; Meriaux, A.-S.; Gayer, E.

    2009-04-01

    Ascension Island is the emergent top of a volcano situated at 7°56'S and 14°22'W in the South Atlantic Ocean, approximately 90 km west of the Mid-Atlantic Ridge and 50 km south of the Ascension Fracture Zone [1, 2]. It rises about 860 m above sea level and the base of the volcano covers about 2000 km2 approximately 3200 m beneath sea level [3]. Volcanic activity is associated with the Mid-Atlantic Ridge, and commenced at 6-7 Ma [2, 4, 5]. The volcanic rocks of Ascension Island are transitional to mildly-alkaline basalt to rhyolite volcanic suite and are distinguished by trace element ratios (e.g. Zr/Nb) [3]. Whereas the age of the trachyte intrusions are well constrained (0.6 - 1.0 Ma) [e.g. 3] the younger basalt suites have not been dated reliably and the low K concentration make Ar/Ar dating difficult. In order to reconstruct the volcanic history of Ascension Island we have used cosmogenic He-3 in olivine and pyroxene phenocrysts from uneroded basalt flows to date the three basalt lava suites that appear to span the range of volcanism. Ages of co-genetic pyroxene and olivine agree within analytical uncertainties. Implanted radiogenic He-4 tends to lower He-3 derived exposure ages therefore some olivine samples were etched with HF/HNO3 to remove about 30% of the sample mass. The so etched olivine is systematically older (by less than 10%) than the unetched samples. The three basalt suites have exposure ages of 300 to 190 ka. The high and intermediate Zr/Nb basalts seem to have been erupted contemporaneously or at least in overlapping events about 300 ka ago. These suites were previously thought to be separated in time on the basis of K-Ar chronology and stratigraphy [3]. The third suite which seams to be a more local vent is erupted between 260 and 190 ka. Our new data indicate the co-existence of different magma chambers with different geochemical signatures. [1] E. Bourdon, C. Hemond, Mineralogy and Petrology 71(2001) 127-138. [2] D.L. Nielson, B.S. Sibbett

  11. [Conceptual models; a power strategy with professional implications].

    PubMed

    Miró Bonet, Margalida

    2010-01-01

    Conceptual models and nursing theories are considered by some authors as standards that guide the thinking on how to be a nurse and practice nursing. Some authors defend that without the use of nursing models it could be difficult to improve the discipline and nursing practice, and even to transform a professional identity linked to submission, obedience and humility. The purpose of this article is not to argue about the truth or falseness, the usefulness, or not, of conceptual nursing models, but to analyse, from a post-structuralist perspective, their use as a power strategy exercised mainly by nurses since the 1970's in Spain and the unintentional professional implications of their adoption by the nursing profession. The basis of this analysis is from the results obtained in the PhD thesis of the author, in which it analysed the processes of continuity and transformation which constituted the professional identity of nurses in Spain between 1956 and 1976. Some political and social consequences are highlighted on nursing practices, on the holistic, humanist and moralist discourses transmitted by nursing models, on occasions compared with bio-pathological, technical and clinical discourses. Copyright © 2010 Elsevier España, S.L. All rights reserved.

  12. Pb isotopes in Ascension Island rocks: oceanic origin for the gabbroic to granitic plutonic xenoliths

    NASA Astrophysics Data System (ADS)

    Weis, D.

    1983-02-01

    The Pb isotopic compositions and U and Pb concentrations of the lava series (alkali basalt to comendite) and of their plutonic xenoliths (gabbro to alkaline granite) of Ascension Island are reported. The data are used to evaluate the source of the xenoliths which formed two differentiation suites: the acidic and intermediate xenoliths together with most of the lavas on the one hand, and the gabbroic xenoliths and a basaltic tuff on the other hand. The Pb isotopic compositions imply a mantle origin for the source magmas of the xenoliths and confirm the possibility of generating granitic rocks in an oceanic environment by fractional crystallization of a mantle-derived magma whose geochemical and isotopic characteristics are comparable to the source magmas of oceanic island basalts.

  13. Assessment of United States and Japanese Athletic Trainers' Satisfaction with Current Ascension Pathways and Interest in Future Transnational Certification

    ERIC Educational Resources Information Center

    Presuto, Dax A.

    2013-01-01

    Background: The purpose of this cross-system and cross-cultural study was to investigate the current athletic training systems in the US and Japan, to assess US and Japanese athletic trainers' satisfaction with current athletic training ascension pathways in their respective country and to determine their interest in future transnational…

  14. Unravelling the magmatic processes behind zoned fall units on Ascension Island, South Atlantic

    NASA Astrophysics Data System (ADS)

    Chamberlain, K. J.; Barclay, J.; Preece, K.; Brown, R. J.; Davidson, J.

    2015-12-01

    Ascension Island, an isolated composite volcano in the south Atlantic, has a wide spectrum of explosive and effusive deposits. Eruptions on the island have produced ash and pumice fall deposits, ignimbrites, scoria cones, lava flows and lava domes, which vary in composition from basalt to rhyolite. We report, for the first time, the presence of multiple, zoned pumice fall deposits. These deposits grade upwards (stepwise or gradationally) from pumice to scoria. We present detailed observations of two key deposits which typify the range in zonation observed in the unusual fall units. Forensic examination of these deposits and their petrological and geochemical characteristics provide critical information about the interactions and processes behind the wide spectrum of magma compositions and past eruptive behaviour on Ascension Island. The first deposit changes gradationally from fayalite-bearing trachytic pumice fall (61.1 wt.% SiO2) at the base, to basaltic trachy-andesite scoria fall (54.5 wt.% SiO2) at the top. The second deposit is more complex. It contains mingled pumice-scoria clasts, has a rapid transition from pumice to scoria and no intermediate clasts were observed. New analyses of H2O, CO2 and key trace elements within melt inclusions combined with systematic whole rock and phenocryst analyses enable us to probe the relationship of these co-erupted magmas to other deposits on the island. This has yielded insights into the magma plumbing system; and improved understanding of the roles that fractional crystallisation and magma mixing play in generating the range in compositions observed at this unique ocean island volcano.

  15. Origin and evolution of silicic magmas at ocean islands: Perspectives from a zoned fall deposit on Ascension Island, South Atlantic

    NASA Astrophysics Data System (ADS)

    Chamberlain, K. J.; Barclay, J.; Preece, K.; Brown, R. J.; Davidson, J. P.

    2016-11-01

    Ascension Island, in the south Atlantic is a composite ocean island volcano with a wide variety of eruptive styles and magmatic compositions evident in its 1 million year subaerial history. In this paper, new observations of a unique zoned fall deposit on the island are presented; the deposit gradationally changes from trachytic pumice at the base, through to trachy-basaltic andesite scoria at the top of the deposit. The key features of the eruptive deposits are described and are coupled with whole rock XRF data, major and trace element analyses of phenocrysts, groundmass glass and melt inclusions from samples of the compositionally-zoned fall deposit to analyse the processes leading up to and driving the explosive eruption. Closed system crystal fractionation is the dominant control on compositional zonation, with the fractionating assemblage dominated by plagioclase feldspar and olivine. This fractionation from the trachy-basaltic andesite magma occurred at pressures of 250 MPa. There is no evidence for multiple stages of evolution involving changing magmatic conditions or the addition of new magmatic pulses preserved within the crystal cargo. Volatile concentrations range from 0.5 to 4.0 wt.% H2O and progressively increase in the more-evolved units, suggesting crystal fractionation concentrated volatiles into the melt phase, eventually causing internal overpressure of the system and eruption of the single compositionally-zoned magma body. Melt inclusion data combined with Fe-Ti oxide modelling suggests that the oxygen fugacity of Ascension Island magmas is not affected by degree of evolution, which concentrates H2O into the liquid phase, and thus the two systems are decoupled on Ascension, similar to that observed in Iceland. This detailed study of the zoned fall deposit on Ascension Island highlights the relatively closed-system evolution of felsic magmas at Ascension Island, in contrast to many other ocean islands, such as Tenerife and Iceland.

  16. Ascension Submarine Canyon, California - Evolution of a multi-head canyon system along a strike-slip continental margin

    USGS Publications Warehouse

    Nagel, D.K.; Mullins, H.T.; Greene, H. Gary

    1986-01-01

    Ascension Submarine Canyon, which lies along the strike-slip (transform) dominated continental margin of central California, consists of two discrete northwestern heads and six less well defined southeastern heads. These eight heads coalesce to form a single submarine canyon near the 2700 m isobath. Detailed seismic stratigraphic data correlated with 19 rock dredge hauls from the walls of the canyon system, suggest that at least one of the two northwestern heads was initially eroded during a Pliocene lowstand of sea level ???3.8 m.y. B.P. Paleogeographic reconstructions indicate that at this time, northwestern Ascension Canyon formed the distal channel of nearby Monterey Canyon and has subsequently been offset by right-lateral, strike-slip faulting along the San Gregorio fault zone. Some of the six southwestern heads of Ascension Canyon may also have been initially eroded as the distal portions of Monterey Canyon during late Pliocene-early Pleistocene sea-level lowstands (???2.8 and 1.75 m.y. B.P.) and subsequently truncated and offset to the northwest. There have also been a minimum of two canyon-cutting episodes within the past 750,000 years, after the entire Ascension Canyon system migrated to the northwest past Monterey Canyon. We attribute these late Pleistocene erosional events to relative lowstands of sea level 750,000 and 18,000 yrs B.P. The late Pleistocene and Holocene evolution of the six southeastern heads also appears to have been controlled by structural uplift of the Ascension-Monterey basement high at the southeastern terminus of the Outer Santa Cruz Basin. We believe that uplift of this basement high sufficiently oversteepened submarine slopes to induce gravitational instability and generate mass movements that resulted in the erosion of the canyon heads. Most significantly, though, our results and interpretations support previous proposals that submarine canyons along strike-slip continental margins can originate by tectonic trunction and lateral

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

    PubMed

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

    2009-01-01

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

  18. Covariate Adjustment Strategy Increases Power in the Randomized Controlled Trial With Discrete-Time Survival Endpoints

    ERIC Educational Resources Information Center

    Safarkhani, Maryam; Moerbeek, Mirjam

    2013-01-01

    In a randomized controlled trial, a decision needs to be made about the total number of subjects for adequate statistical power. One way to increase the power of a trial is by including a predictive covariate in the model. In this article, the effects of various covariate adjustment strategies on increasing the power is studied for discrete-time…

  19. Power Relationships, Interactional Dominance and Manipulation Strategies in Group Conversations of Turkish-Danish Children.

    ERIC Educational Resources Information Center

    Madsen, Lian Malai

    2003-01-01

    Focuses on interactional dominance and power wielding in bilingual conversation among school children. Finds that different pragmatic strategies are used by bilingual children as a means of negotiating power relationships and identities, but that the social relations and the power bases brought into the conversations by interactants make the…

  20. Covariate Adjustment Strategy Increases Power in the Randomized Controlled Trial With Discrete-Time Survival Endpoints

    ERIC Educational Resources Information Center

    Safarkhani, Maryam; Moerbeek, Mirjam

    2013-01-01

    In a randomized controlled trial, a decision needs to be made about the total number of subjects for adequate statistical power. One way to increase the power of a trial is by including a predictive covariate in the model. In this article, the effects of various covariate adjustment strategies on increasing the power is studied for discrete-time…

  1. Wireless Power Transfer Strategies for Implantable Bioelectronics: Methodological Review.

    PubMed

    Agarwal, Kush; Jegadeesan, Rangarajan; Guo, Yong-Xin; Thakor, Nitish V

    2017-03-16

    Neural implants have emerged over the last decade as highly effective solutions for the treatment of dysfunctions and disorders of the nervous system. These implants establish a direct, often bidirectional, interface to the nervous system, both sensing neural signals and providing therapeutic treatments. As a result of the technological progress and successful clinical demonstrations, completely implantable solutions have become a reality and are now commercially available for the treatment of various functional disorders. Central to this development is the wireless power transfer (WPT) that has enabled implantable medical devices (IMDs) to function for extended durations in mobile subjects. In this review, we present the theory, link design, and challenges, along with their probable solutions for the traditional near-field resonant inductively coupled WPT, capacitively coupled short ranged WPT, and more recently developed ultrasonic, mid-field and far-field coupled WPT technologies for implantable applications. A comparison of various power transfer methods, based on their power budgets and WPT range follows. Power requirements of specific implants like cochlear, retinal, cortical and peripheral are also considered and currently available IMD solutions are discussed. Patient's safety concerns with respect to electrical, biological, physical, electromagnetic interference and cyber security from an implanted neurotech device are also explored in this review. Finally, we discuss and anticipate future developments that will enhance the capabilities of current-day wirelessly powered implants and make them more efficient and integrable with other electronic components in IMDs.

  2. The Power of Praise--A Strategy for Effective Principals.

    ERIC Educational Resources Information Center

    Blase, Joseph; Kirby, Peggy C.

    1992-01-01

    In a recent study, teachers linked use of praise to principals' goals of promoting and reinforcing instructional performance. Teachers viewed praise as a positive, effective influence strategy that helped boost their confidence and pride and enhance feelings of satisfaction and belonging. Only work-related praise was viewed as influential.…

  3. An Electric Power Purchase Strategy for Bilateral Contracts Focusing on Reliability of Customers

    NASA Astrophysics Data System (ADS)

    Niioka, Satoru; Yokoyama, Ryuichi

    With introducing the competitive electrical power market, large-scale customers can select electric power suppliers. Customers need to consider not only the economical efficiency but also reliability, to decide the amount of electrical power to purchase. This paper develops an economic electric power purchase strategy for customers focusing on reliability. A bilateral contract model expressing electric power suppliers as generators with a forced outage rate is proposed and introduced to assess potential outage risks of the bilateral contract between an electric power supplier and a customer. The outage-related cost, consisting of potential outage risks and the estimated outage cost, is also proposed and introduced as an index of the reliability on the customer side, and an optimal reliability level of a customer is obtained by using the index. Several numerical examples demonstrate the availability of the proposed electric power purchase decision method and reliability improvement strategies for customers are discussed.

  4. Optimization strategy for element sizing in hybrid power systems

    NASA Astrophysics Data System (ADS)

    del Real, Alejandro J.; Arce, Alicia; Bordons, Carlos

    This paper presents a procedure to evaluate the optimal element sizing of hybrid power systems. In order to generalize the problem, this work exploits the "energy hub" formulation previously presented in the literature, defining an energy hub as an interface among energy producers, consumers and the transportation infrastructure. The resulting optimization minimizes an objective function which is based on costs and efficiencies of the system elements, while taking into account the hub model, energy and power constraints and estimated operational conditions, such as energy prices, input power flow availability and output energy demand. The resulting optimal architecture also constitutes a framework for further real-time control designs. Moreover, an example of a hybrid storage system is considered. In particular, the architecture of a hybrid plant incorporating a wind generator, batteries and intermediate hydrogen storage is optimized, based on real wind data and averaged residential demands, also taking into account possible estimation errors. The hydrogen system integrates an electrolyzer, a fuel cell stack and hydrogen tanks. The resulting optimal cost of such hybrid power plant is compared with the equivalent hydrogen-only and battery-only systems, showing improvements in investment costs of almost 30% in the worst case.

  5. Automation Power Energy Management Strategy for Mobile Telecom Industry

    NASA Astrophysics Data System (ADS)

    Hwang, Jong-Ching; Chen, Jung-Chin; Pan, Jeng-Shyang; Huang, Yi-Chao

    The aim of this research is to study the power energy cost reduction of the mobile telecom industry through the supervisor control and data acquisition (SCADA) system application during globalization and liberalization competition. Yet this management system can be proposed functions: operating monitors, the analysis on load characteristics and dropping the cost of management.

  6. Passive mitigation strategies for mode instabilities in high-power fiber laser systems.

    PubMed

    Jauregui, Cesar; Otto, Hans-Jürgen; Stutzki, Fabian; Jansen, Florian; Limpert, Jens; Tünnermann, Andreas

    2013-08-12

    Mode instabilities have quickly become the most limiting effect when it comes to scaling the output average power of fiber laser systems. In consequence, there is an urgent need for effective strategies to mitigate it and, thus, to increase the power threshold at which it appears. Passive mitigation strategies can be classified into intrinsic, which are related to the fiber design, and extrinsic, which require a modification of the setup. In order to evaluate the impact of mitigation strategies, a means to calculate its power threshold and predict its behavior is required. In this paper we present a simple semi-analytic formula that is able to predict the changes of the mode instability threshold by analyzing the strength of the thermally-induced waveguide perturbations. Furthermore, we propose two passive mitigation strategies, one intrinsic and one extrinsic, that should lead to a significant increase of the power threshold of mode instabilities.

  7. Multi-load Groups Coordinated Load Control Strategy Considering Power Network Constraints

    NASA Astrophysics Data System (ADS)

    Liu, Meng; Zhao, Binchao; Wang, Jun; Zhang, Guohui; Wang, Xin

    2017-05-01

    Loads with energy storage property can actively participate in power balance for power systems, this paper takes air conditioner as a controllable load example, proposing a multi-load groups coordinated load control strategy considering power network constraints. Firstly, two load control modes considering recovery of load diversity are designed, blocking power oscillation of aggregated air conditioners. As the same time, air conditioner temperature setpoint recovery control strategy is presented to avoid power recovery peak. Considering inherent characteristics of two load control modes, an coordinated load control mode is designed by combining the both. Basing on this, a multi-load groups coordinated load control strategy is proposed. During the implementing of load control, power network constraints should be satisfied. An indice which can reflect the security of power system operating is defined. By minimizing its value through optimization, the change of air conditioning loads’ aggregated power on each load bus can be calculated. Simulations are conducted on an air conditioners group and New England 10-generator 39-bus system, verifying the effectiveness of the proposed multi-load groups coordinated load control strategy considering power network constraints.

  8. A flexible active and reactive power control strategy for a variable speed constant frequency generating system

    SciTech Connect

    Tang, Y.; Xu, L.

    1995-07-01

    Variable-speed constant-frequency generating systems are used in wind power, hydro power, aerospace, and naval power generations to enhance efficiency and reduce friction. In these applications, an attractive candidate is the slip power recovery system comprising of doubly excited induction machine or doubly excited brushless reluctance machine and PWM converters with a dc link. In this paper, a flexible active and reactive power control strategy is developed, such that the optimal torque-speed profile of the turbine can be followed and overall reactive power can be controlled, while the machine copper losses have been minimized. At the same time, harmonics injected into the power network has also been minimized. In this manner, the system can function as both a high-efficient power generator and a flexible reactive power compensator.

  9. Assessing China’s Soft Power in Asia: Implications for U.S. Strategy

    DTIC Science & Technology

    2012-04-01

    and film …the freedom is not there. (The Chinese government) really tries to control and manage it, and there is self- censorship as well. That is...Assessing China’s Soft Power in Asia : Implications for U.S. Strategy by Colonel Michael R. Lwin United States Army...TITLE AND SUBTITLE 5a. CONTRACT NUMBER Assessing China’s Soft Power in Asia : Implications for U.S. Strategy 5b. GRANT NUMBER 5c

  10. Morphology of the proximal and middle phalanx of fingers with regard to the Ascension PyroCarbon PIP total joint.

    PubMed

    Ries, C; Zhang, W; Burkhart, K J; Neiss, W F; Müller, L P; Hohendorff, B

    2014-07-01

    The Ascension PyroCarbon prosthesis has been used in proximal interphalangeal joint osteoarthritis. The dimensions of the intramedullary distal metadiaphyseal canal (isthmus) of the proximal phalanx and the base of the middle phalanx of cadaver fingers were investigated radiographically (n = 304) and macroscopically (n = 152). In up to 30% of the phalanges, the isthmus was smaller than the stem of the smallest proximal component size. The distal component head was always smaller than the middle phalanx base. Insertion and success of the Ascension PyroCarbon prosthesis is strongly dependent on bone morphology. A critical examination of the isthmus in radiographs is recommended in planning. If the isthmus is clearly smaller than the smallest proximal component, insertion of the prosthesis could be inadvisable. A clear mismatch between the distal component and the middle phalanx base should be avoided due to the potential risk for late subsidence and failure of the prosthesis.

  11. Ascension health's demonstration of full disclosure protocol for unexpected events during labor and delivery shows promise.

    PubMed

    Hendrich, Ann; McCoy, Christine Kocot; Gale, Jane; Sparkman, Lora; Santos, Palmira

    2014-01-01

    Communicating openly and honestly with patients and families about unexpected medical events-a policy known as full disclosure-improves outcomes for patients and providers. Although many certification and licensing organizations have declared full disclosure to be imperative, the adoption of and adherence to a full disclosure protocol is not common practice in most clinical settings. We conducted a case study of Ascension Health's implementation of a full disclosure protocol at five labor and delivery demonstration sites. Twenty-seven months after implementation, the rate of full disclosure had increased by 221 percent. Practitioners saw insurers' acceptance of the full disclosure protocol, consistent and ongoing leadership by local practitioners and hospitals, the establishment of a well-trained local investigation and disclosure team, and disclosure training for practitioners as key catalysts for change. Lessons learned from this multisite initiative can inform liability insurers and guide providers who are committed to ensuring that full disclosure becomes the only response to unexpected medical events.

  12. Study of a coincident observation between the ROCSAT-1 density irregularity and Ascension Island scintillation

    NASA Astrophysics Data System (ADS)

    Liu, Y. H.; Chao, C. K.; Su, S.-Y.; Liu, C. H.

    2012-10-01

    A coincident observation that occurred on 24 March 2000 between the irregularity structure measured by ROCSAT-1 and the scintillation experiment at the Ascension Island has been studied. The study of scintillation statistics is carried out first, and the results show that the Nakagami distribution can portray the normalized intensity of the L-band scintillation at various S4 values, up to S4 equal to 1.4. Moreover, the departure of frequency dependence on S4 predicted by the weak scintillation is noticed due to multiple forward scattering effects. The coincident feature between the characteristics of irregularity structure and the scintillation variation are then studied. The causal relationship between the fluctuation of ion density and the scintillation variation is obtained. A numerical simulation using the parabolic wave equation has been carried out with the ROCSAT-1 data in space to compare with the ground scintillation observation. The results show the reasonable scintillation level at the coincident time to indicate a direct relationship between the irregularity structure and the scintillation in both temporal and amplitudinal variations. Finally, some assumptions and limitations of the simulation model are discussed.

  13. Review of Reactive Power Dispatch Strategies for Loss Minimization in a DFIG-based Wind Farm

    DOE PAGES

    Zhang, Baohua; Hu, Weihao; Hou, Peng; ...

    2017-06-27

    This study reviews and compares the performance of reactive power dispatch strategies for the loss minimization of Doubly Fed Induction Generator (DFIG)-based Wind Farms (WFs). Twelve possible combinations of three WF level reactive power dispatch strategies and four Wind Turbine (WT) level reactive power control strategies are investigated. All of the combined strategies are formulated based on the comprehensive loss models of WFs, including the loss models of DFIGs, converters, filters, transformers, and cables of the collection system. Optimization problems are solved by a Modified Particle Swarm Optimization (MPSO) algorithm. The effectiveness of these strategies is evaluated by simulations onmore » a carefully designed WF under a series of cases with different wind speeds and reactive power requirements of the WF. The wind speed at each WT inside the WF is calculated using the Jensen wake model. The results show that the best reactive power dispatch strategy for loss minimization comes when the WF level strategy and WT level control are coordinated and the losses from each device in the WF are considered in the objective.« less

  14. Strategies for emission reduction from thermal power plants.

    PubMed

    Prisyazhniuk, Vitaly A

    2006-07-01

    Major polluters of man's environment are thermal power stations (TPS) and power plants, which discharge into the atmosphere the basic product of carbon fuel combustion, CO2, which results in a build-up of the greenhouse effect and global warm-up of our planet's climate. This paper is intended to show that the way to attain environmental safety of the TPS and to abide by the decisions of the Kyoto Protocol lies in raising the efficiency of the heat power stations and reducing their fuel consumption by using nonconventional thermal cycles. Certain equations have been derived to define the quantitative interrelationship between the growth of efficiency of the TPS, decrease in fuel consumption and reduction of discharge of dust, fuel combustion gases, and heat into the environment. New ideas and new technological approaches that result in raising the efficiency of the TPS are briefly covered: magneto-hydrodynamic resonance, the Kalina cycle, and utilizing the ambient heat by using, as the working medium, low-boiling substances.

  15. The Acceptance Strategy for Nuclear Power Plant In Indonesia

    SciTech Connect

    Suhaemi, Tjipta; Syaukat, Achmad

    2010-06-22

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

  16. Impact of Managerial Power on Persuasive Strategy Selection by Female and Male Managers.

    ERIC Educational Resources Information Center

    Hirokawa, Randy Y.; And Others

    1990-01-01

    Investigates the persuasive communication of male and female middle managers, focusing on the mediating influence of a manager's power on his or her selection of anticipated compliance-gaining message strategies. Finds no marked differences between the genders in the types of strategies and tactics used to influence subordinates. (KEH)

  17. Potentiality Prediction of Electric Power Replacement Based on Power Market Development Strategy

    NASA Astrophysics Data System (ADS)

    Miao, Bo; Yang, Shuo; Liu, Qiang; Lin, Jingyi; Zhao, Le; Liu, Chang; Li, Bin

    2017-05-01

    The application of electric power replacement plays an important role in promoting the development of energy conservation and emission reduction in our country. To exploit the potentiality of regional electric power replacement, the regional GDP (gross domestic product) and energy consumption are taken as potentiality evaluation indicators. The principal component factors are extracted with PCA (principal component analysis), and the integral potentiality analysis is made to the potentiality of electric power replacement in the national various regions; a region is taken as a research object, and the potentiality of electric power replacement is defined and quantified. The analytical model for the potentiality of multi-scenario electric power replacement is developed, and prediction is made to the energy consumption with the grey prediction model. The relevant theoretical research is utilized to realize prediction analysis on the potentiality amount of multi-scenario electric power replacement.

  18. The Likelihood of Use of Social Power Strategies by School Psychologists when Consulting with Teachers

    ERIC Educational Resources Information Center

    Wilson, Kristen E.; Erchul, William P.; Raven, Bertram H.

    2008-01-01

    The Interpersonal Power Inventory (IPI) has been applied previously to investigate school psychologists engaged in problem-solving consultation with teachers concerning students having various learning and adjustment problems. Relevant prior findings include (a) consultants and teachers both perceive soft power strategies as more effective than…

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

    ERIC Educational Resources Information Center

    Getty, Kimberly C.; Erchul, William P.

    2009-01-01

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

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

    ERIC Educational Resources Information Center

    Getty, Kimberly C.; Erchul, William P.

    2009-01-01

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

  1. The Likelihood of Use of Social Power Strategies by School Psychologists when Consulting with Teachers

    ERIC Educational Resources Information Center

    Wilson, Kristen E.; Erchul, William P.; Raven, Bertram H.

    2008-01-01

    The Interpersonal Power Inventory (IPI) has been applied previously to investigate school psychologists engaged in problem-solving consultation with teachers concerning students having various learning and adjustment problems. Relevant prior findings include (a) consultants and teachers both perceive soft power strategies as more effective than…

  2. Power of Competing Strategies of Linkage Analysis for Complex Traits

    PubMed Central

    Ma, Jianzhong; Daw, E. Warwick; Amos, Christopher I.

    2010-01-01

    Variance components (VC) and the Bayesian Markov chain Monte Carlo (MCMC) analysis are two of the widely used linkage analysis approaches to mapping genes for complex quantitative traits. Both approaches can handle extended pedigrees and multiple markers and do not require a prespecified genetic model. In this study, we used simulated data to compare the performance of these two approaches with the traditional parametric linkage analysis. Using simulated data sets without linkage between a quantitative trait and the markers, we estimated a critical value for various test scores used in VC or MCMC and the location (LOC) score at a fixed level of significance (5%). These critical values were then used to determine the power for the three methods for simulated data sets with linkage. We found that both the VC and MCMC approaches worked well, compared with the LOC score, when there was only one gene underlying the quantitative trait; however, VC had higher power than the other methods in a simulation study of a complex phenotype influenced by more than one gene. We also compared two implementations of MCMC analysis, finding interpretation of results using the log of placement score was more accurate for linkage inference than the Bayes factor but required much more intensive simulation studies. PMID:20551674

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

    PubMed

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

    2017-11-01

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

  4. Methane at Ascension Island, southern tropical Atlantic Ocean: continuous ground measurement and vertical profiling above the Trade-Wind Inversion

    NASA Astrophysics Data System (ADS)

    Lowry, David; Brownlow, Rebecca; Fisher, Rebecca; Nisbet, Euan; Lanoisellé, Mathias; France, James; Thomas, Rick; Mackenzie, Rob; Richardson, Tom; Greatwood, Colin; Freer, Jim; Cain, Michelle; Warwick, Nicola; Pyle, John

    2015-04-01

    Methane mixing ratios have been rising rapidly worldwide since 2007. At Ascension Island (8oS in the equatorial Atlantic), a sustained rise has occurred. Prior to 2010, growth was comparable to other regions, but in 2010-11, during a strong la Nina event, the increase was 10ppb year-on-year. Reduced growth followed in 2011-12, but in 2012-13 strong growth resumed and continues. This rise has been accompanied by a shift to lighter δ13CCH4 values in 2010-11 in the equatorial tropics. The most likely cause of this shift is emissions from isotopically 'light' biological sources in the equatorial and savanna tropics. Ascension Island is in the Trade Wind belt of the tropical Atlantic, perfectly located to measure the South Atlantic marine boundary layer. The SE Trade Winds are almost invariant, derived from the deep South Atlantic and with little contact with Africa. However, above the Trade Wind Inversion (TWI) at about 1200-2000m asl, the air masses are very different, coming dominantly from tropical Africa and occasionally S. America. Depending on season, air above the TWI is sourced from the African southern savanna grasslands or the equatorial wetlands of Congo and Uganda, with inputs of air also from southern tropical S. America (Brazil, Paraguay, Bolivia). African methane sources are a major contributor to the global methane budget, but although local campaign studies have been made, African emissions are not well studied in bulk. In September 2014, an octocopter was used to retrieve air samples from heights up to 2700m asl on Ascension (see Thomas, R. et al, this volume). This allowed sampling through the marine boundary layer, across the TWI cloud layer, and into the mid-troposphere. Samples were collected in part-filled 5L Tedlar bags, which were analysed for CH4 concentration using Royal Holloway's Picarro 1301 CRDS system at the Met Office, Ascension. This has high precision and accuracy, with a 6-gas calibration suite. Bags were then analysed in the UK for

  5. Power-aware provisioning strategy with shared path protection in optical WDM networks

    NASA Astrophysics Data System (ADS)

    Bao, Ning-Hai; Li, Le-Min; Yu, Hong-Fang; Zhang, Zhi-Zhong; Luo, Hong-Bin

    2012-03-01

    As the Internet continues to grow, the power consumption of telecommunication networks is rising at a considerable speed, which seriously increases the operational expenditure and greenhouse gas emission. Since optical Wavelength Division Multiplexing (WDM) networks are currently the most promising network infrastructures, power saving issue on these networks has received more attention in recent years. In traditional optical WDM networks, a large amount of power is drained by the redundant idle resources and reserved backup resources although these powered on resources do not carry traffic in most of the time. In order to reduce the network power consumption, turning off the corresponding network components or switching them to a low-power, standby state (or called sleep mode) is a promising greening approach. In this paper, we study the power-aware provisioning strategies and propose a sleep mode based Power-Aware Shared Path Protection (PASPP) heuristic algorithm to achieve the power efficiency of optical WDM networks. By jointly utilizing link-cost and fiber-cost in path routing, resource assignment, and resource release, PASPP makes working paths and backup paths converge on different fibers as much as possible, and switch idle and backup components to sleep mode to realize power saving. Simulation results show that our PASPP can obtain notable power saving and achieve satisfactory tradeoff between power efficiency and blocking probability with respect to Power-Unaware Shared Path Protection (PUSPP).

  6. Calibration of Hydrophone Stations: Lessons Learned from the Ascension Island Experiment

    SciTech Connect

    Harben, P E; Rodgers, A J

    2000-07-11

    Calibration of hydroacoustic stations for nuclear explosion monitoring is important for increasing monitoring capability and confidence from newly installed stations and from existing stations. Calibration of hydroacoustic stations is herein defined as the near-field precision location of the hydrophones and determination of the amplitude response; and the regional-scale calibration of acoustic traveltimes, bathymetric shadowing, diffraction, and reflection as recorded at a particular station. An important type of calibration not considered here is ocean-basin-scale calibration of a hydroacoustic monitoring system. To understand how to best conduct hydroacoustic station calibrations, an experiment was conducted in May 1999 at Ascension Island in the South Atlantic Ocean. The experiment made use of a British oceanographic research vessel towing an airgun array and collected data over three MILS hydrophones that were in use by the National Data Center and the International Data Center. From the towed airgun data we were able to determine the location for each of the three hydrophones to accuracy better than 100 meters in latitude, longitude, and depth. The agreement with the nominal locations was excellent in depth and to within 1 km in latitude and longitude. The depths determined for the hydrophones and the ocean bottom depths determined from the ship's sonar system force the conclusion that all three hydrophones are located at or near the ocean bottom. Amplitude frequency response of the hydrophones was also calibrated using a calibrated temporarily deployed hydrophone to determine the airgun source function. With the source function known, the amplitude and phase response of the hydrophones could be deconvolved from the recorded waveforms provided a ''pure'' source waveform arrival is identified on the recording. Unfortunately, since the hydrophones are located near the ocean bottom, the recording is contaminated by reflections and scattered energy, making a

  7. Unified power flow controller: Modeling, stability analysis, control strategy and control system design

    NASA Astrophysics Data System (ADS)

    Sreenivasachar, Kannan

    2001-07-01

    Unified power flow controller (UPFC) has been the most versatile Flexible AC Transmission System (FACTS) device due to its ability to control real and reactive power flow on transmission lines while controlling the voltage of the bus to which it is connected. UPFC being a multi-variable power system controller it is necessary to analyze its effect on power system operation. To study the performance of the UPFC in damping power oscillations using PSCAD-EMTDC software, a de-coupled control system has been designed for the shunt inverter to control the UPFC bus voltage and the DC link capacitor voltage. The series inverter of a UPFC controls the real power flow in the transmission line. One problem associated with using a high gain PI controller (used to achieve fast control of transmission line real power flow) for the series inverter of a UPFC to control the real power flow in a transmission line is the presence of low damping. This problem is solved in this research by using a fuzzy controller. A method to model a fuzzy controller in PSCAD-EMTDC software has also been described. Further, in order to facilitate proper operation between the series and the shunt inverter control system, a new real power coordination controller has been developed and its performance was evaluated. The other problem concerning the operation of a UPFC is with respect to transmission line reactive power flow control. Step changes to transmission line reactive power references have significant impact on the UPFC bus voltage. To reduce the adverse effect of step changes in transmission line reactive power references on the UPFC bus voltage, a new reactive power coordination controller has been designed. Transient response studies have been conducted using PSCAD-EMTDC software to show the improvement in power oscillation damping with UPFC. These simulations include the real and reactive power coordination controllers. Finally, a new control strategy has been proposed for UPFC. In this

  8. Power sharing. A transformational strategy for nurse retention, effectiveness, and extra effort.

    PubMed

    Trofino, Joan

    2003-01-01

    Power sharing with staff nurses is an essential strategy for organizational transformation. The current competitive health care environment requires a powerful team of participants, including staff at all levels, to provide health care in mutual partnership. The challenges of today's competitive and global environment call for collegial relationships among nurse executive leadership, middle nurse managers, and staff nurses. Research has demonstrated that middle nurse managers maintain primary responsibility for staff nurse retention. A higher retention rate was reported among nurses who were very satisfied with their nurse managers. Nurses considered favorably nurse managers who value staff contributions, promote information sharing, and exert influence for a stable work environment. Furthermore, as staff nurse satisfaction increased, effectiveness and extra effort also increased when staff nurses perceived transformational leadership strategies. Strategies for power sharing include serving as role models and mentors, energizing staff, resisting attitudes of staff ownership, reducing staff nurse stress of leader presence, and information sharing and commendations at meetings.

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

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

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

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

    NASA Astrophysics Data System (ADS)

    Hafezalkotob, Ashkan; Mahmoudi, Reza

    2017-03-01

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

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

    NASA Astrophysics Data System (ADS)

    Hafezalkotob, Ashkan; Mahmoudi, Reza

    2017-03-01

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

  12. Sharing Power? Prospects for a U.S. Concert-Balance Strategy

    DTIC Science & Technology

    2013-04-01

    balancing . Joseph Joffe, Überpower: The Imperial Temptation of America, New York: W. W. Norton , 2006, pp. 127-157. 41. Paul Kennedy, The Rise and...REPORT TYPE 3. DATES COVERED 00-00-2013 to 00-00-2013 4. TITLE AND SUBTITLE Sharing Power? Prospects for a U.S. Concert- Balance Strategy 5a...College Press SHARING POWER? PROSPECTS FOR A U.S. CONCERT- BALANCE STRATEGY Patrick Porter April 2013 The views expressed in this report are those of

  13. Passive seismoacoustic imaging from the seafloor to the lithosphere: Methods and applications to New Zealand and Ascension Island

    NASA Astrophysics Data System (ADS)

    Ball, Justin S.

    Passive-source seismic methods often rely on the isolation of transient signals such as distant earthquakes from a pervasive background of ambient noise. In marine seismology, discriminating signals from noise is particularly complicated due to the efficient wave propagation characteristics of the ocean and sediments, and oceanographic noise sources including long-period ocean surface gravity waves. Furthermore, high-amplitude structural reverberations near the receiver modulate and obscure teleseismic arrivals targeted by the analyst. In this thesis I further the development of methods to both accommodate the signal-generated noise and utilize the rich ambient noise wavefield in the ocean. I apply these methods to image subsurface structure at scales from the shallow sediments to the lithospheric mantle beneath the South Island of New Zealand and Ascension Island. I first utilize ambient noise in the form of infragravity waves and Rayleigh waves, which both sense shear structure at depth, in conjunction with reverberations in P-S wave receiver functions to model shallow sediment structure offshore New Zealand using a Markov Chain Monte Carlo algorithm. I then turn my focus to the theory and application of Rayleigh/Scholte wave noise interferometry. First I investigate the effects of bathymetric variations on microseism-band modal propagation between two hydrophones moored off Ascension Island. I model the range-dependent dispersion observed in the noise correlation functions from Ascension data as the result of double mode-converted Scholte-Moho headwave propagation, and thereby demonstrate the feasibility of probing oceanic crustal and upper mantle structure using moored hydrophone data. Lastly I apply a combination of ambient noise and teleseismic Rayleigh wave tomography to image the shear structure of the mantle lithosphere beneath the continental collision zone of the South Island of New Zealand. The resulting models include high-wavespeed anomalies

  14. Theoretical strategy for choosing piggyback intraocular lens powers in young children.

    PubMed

    Boisvert, Chantal; Beverly, David T; McClatchey, Scott K

    2009-12-01

    The normal growth of a young child's pseudophakic eye can result in a large myopic shift. Temporary polypseudophakia using piggyback intraocular lenses (IOLs) has been proposed as a means to reduce the amount of myopic shift by removing the anterior IOL when the eye becomes sufficiently myopic. Since the rate of refractive growth can be used to predict the refractive curve over time in pseudophakic children, we used this knowledge to develop a theoretical strategy for choosing IOL power combinations for temporary polypseudophakia. We used a novel Pediatric Piggyback IOL Calculator to develop a strategy for choosing the powers of the anterior and posterior IOLs. We graphed the predicted results for several combinations of piggyback IOL powers and chose the combination of IOL powers that appeared to give the best results, based on the known rate of refractive growth (5.4 D) and its standard deviation (2.4 D). We aimed for a combination to minimize the hyperopic or myopic refractive error during the first 6 years of life to facilitate amblyopia management and minimize the refractive error at age 20 years. We found optimal results when the initial postoperative goal refraction with polypseudophakia was moderate hyperopia and the anterior IOL had approximately 20% of the total required IOL power. This theoretical strategy can be used to determine piggyback IOL powers to use in children.

  15. Hydrodynamic theory for reverse brazil nut segregation and the non-monotonic ascension dynamics

    NASA Astrophysics Data System (ADS)

    Alam, Meheboob; Trujillo, L.; Herrmann, H. J.

    2006-08-01

    larger) the intruder, the faster it ascends. The peak on the rise-time curve decreases in height and shifts to a lower density-ratio as we increase the pseudo-thermal buoyancy force. The rise (/sink) time diverges near the threshold density-ratio for reverse-segregation. Our theory offers a unified description for the (reverse) Brazil-nut segregation and the nonmonotonic ascension dynamics of Brazil-nuts.

  16. Search for first harmonic modulation in the right ascension distribution of cosmic rays detected at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Pierre Auger Collaboration; Abreu, P.; Aglietta, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antičić, T.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellido, J. A.; Benzvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Domenico, M.; de Donato, C.; de Jong, S. J.; de La Vega, G.; de Mello, W. J. M.; de Mello Neto, J. R. T.; de Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; Del Peral, L.; Deligny, O.; Dembinski, H.; Denkiewicz, A.; di Giulio, C.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; Dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; Facal San Luis, P.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipčič, A.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fröhlich, U.; Fuchs, B.; Gamarra, R. F.; Gambetta, S.; García, B.; García Gámez, D.; Garcia-Pinto, D.; Gascon, A.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Góra, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Griffith, N.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Holmes, V. C.; Homola, P.; Hörandel, J. R.; Horneffer, A.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jiraskova, S.; Kadija, K.; Kampert, K. H.; Karhan, P.; Karova, T.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Meurer, C.; Mićanović, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafá, M.; Moura, C. A.; Mueller, S.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Nhung, P. T.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parrisius, J.; Parsons, R. D.; Pastor, S.; Paul, T.; Pech, M.; PeĶala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Risse, M.; Ristori, P.; Rivera, H.; Rivière, C.; Rizi, V.; Robledo, C.; Rodrigues de Carvalho, W.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouillé-D'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Rühle, C.; Salamida, F.; Salazar, H.; Salina, G.; Sánchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovánek, P.; Schroeder, F.; Schulte, S.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Semikoz, D.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Šuša, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Szuba, M.; Tamashiro, A.; Tapia, A.; Taşcău, O.; Tcaciuc, R.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tomé, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.; Vargas Cárdenas, B.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Videla, M.; Villaseñor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Younk, P.; Yuan, G.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.

    2011-03-01

    We present the results of searches for dipolar-type anisotropies in different energy ranges above 2.5 × 1017 eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% C.L. for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations.

  17. Power Strategy in DC/DC Converters to Increase Efficiency of Electrical Stimulators.

    PubMed

    Aqueveque, Pablo; Acuña, Vicente; Saavedra, Francisco; Debelle, Adrien; Lonys, Laurent; Julémont, Nicolas; Huberland, François; Godfraind, Carmen; Nonclercq, Antoine

    2016-06-13

    Power efficiency is critical for electrical stimulators. Battery life of wearable stimulators and wireless power transmission in implanted systems are common limiting factors. Boost DC/DC converters are typically needed to increase the supply voltage of the output stage. Traditionally, boost DC/DC converters are used with fast control to regulate the supply voltage of the output. However, since stimulators are acting as current sources, such voltage regulation is not needed. Banking on this, this paper presents a DC/DC conversion strategy aiming to increase power efficiency. It compares, in terms of efficiency, the traditional use of boost converters to two alternatives that could be implemented in future hardware designs.

  18. The Role of Soft Power in China’s Security Strategy: Case Studies on the South China Sea and Taiwan

    DTIC Science & Technology

    2017-06-09

    THE ROLE OF SOFT POWER IN CHINA’S SECURITY STRATEGY : CASE STUDIES ON THE SOUTH CHINA SEA AND TAIWAN A thesis presented to the...in the South China Sea. The study demonstrates that soft power is integrated into China’s security strategy , and involves a wide range of sources...Thesis Title: The Role of Soft Power in China’s Security Strategy : Case Studies on the South China Sea and Taiwan Approved by

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

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

  20. Simulation and comparison of different operational strategies for storage utilization in concentrated solar power plants

    NASA Astrophysics Data System (ADS)

    García-Barberena, Javier; Erdocia, Ioseba

    2016-05-01

    The increase of electric power demand and the wish to protect the environment are leading to a change in the energy sources. Conventional energy plants are losing strength against the renewable energy plants and, in particular, solar energy plants have a huge potential to provide clean energy supply for the increasing world's energy demand. Among the existing solar technologies, Concentrating Solar Power (CSP) is one of the most promising technologies. One of the major advantages of CSP plants is the technically feasible and cost-effective integration of Thermal Energy Storage (TES) systems. To increase the plant dispatchability, it is possible to create different operational strategies defining how such TES system is used. In this work, different strategies with different overall goals have been simulated over a complete year and the results are presented and compared here to demonstrate the capabilities of the operational strategies towards an increased dispatchability and plant economic effectiveness. The analysis shows that different strategies may lead to significant differences in the plant annual production, expected economic incomes, number of power block stops, mean efficiency, etc. Specifically, it has been found that the economic incomes of a plant can be increased (+1.3%) even with a decreased total energy production (-1.5%) if the production is scheduled to follow a demand/price curve. Also, dramatic reduction in the number of turbine stops (-67%) can be achieved if the plant is operated towards this objective. The strategies presented in this study have not been optimized towards any specific objective, but only created to show the potential of well designed operational strategies in CSP plants. Therefore, many other strategies as well as optimized versions of the strategies explained below are possible and will be analyzed in future works.

  1. Predictive-model-based dynamic coordination control strategy for power-split hybrid electric bus

    NASA Astrophysics Data System (ADS)

    Zeng, Xiaohua; Yang, Nannan; Wang, Junnian; Song, Dafeng; Zhang, Nong; Shang, Mingli; Liu, Jianxin

    2015-08-01

    Parameter-matching methods and optimal control strategies of the top-selling hybrid electric vehicle (HEV), namely, power-split HEV, are widely studied. In particular, extant research on control strategy focuses on the steady-state energy management strategy to obtain better fuel economy. However, given that multi-power sources are highly coupled in power-split HEVs and influence one another during mode shifting, conducting research on dynamic coordination control strategy (DCCS) to achieve riding comfort is also important. This paper proposes a predictive-model-based DCCS. First, the dynamic model of the objective power-split HEV is built and the mode shifting process is analyzed based on the developed model to determine the reason for the system shock generated. Engine torque estimation algorithm is then designed according to the principle of the nonlinear observer, and the prediction model of the degree of shock is established based on the theory of model predictive control. Finally, the DCCS with adaptation for a complex driving cycle is realized by combining the feedback control and the predictive model. The presented DCCS is validated on the co-simulation platform of AMESim and Simulink. Results show that the shock during mode shifting is well controlled, thereby improving riding comfort.

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

    SciTech Connect

    Ying, R.

    1996-12-31

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

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

    ERIC Educational Resources Information Center

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

    2009-01-01

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

  4. Analysis of Strategies for Reducing Multiple Emissions from Electric Power Plants: SO2, Nox, CO2

    EIA Publications

    2001-01-01

    This report responds to a request received from Senator David McIntosh on June 29, 2000 to analyze the impacts on energy consumers and producers of coordinated strategies to reduce emissions of sulfur dioxide, nitrogen oxides, and carbon dioxide at U.S. power plants.

  5. A Teaching Strategy for Developing the Power of Observation in Science Education

    ERIC Educational Resources Information Center

    Oguz-Unver, Ayse; Yurumezoglu, Kemal

    2009-01-01

    Despite the importance of observation in knowledge building, it has received less attention than experimental forms of inquiry in science education. Therefore, the aims of this study are to use observation strategies for developing the power of observation in science education and to develop student teachers' skills of observation process. The…

  6. Optimal Strategy of Efficiency Power Plant with Battery Electric Vehicle in Distribution Network

    NASA Astrophysics Data System (ADS)

    Ma, Tao; Su, Su; Li, Shunxin; Wang, Wei; Yang, Tiantian; Li, Mengjuan; Ota, Yutaka

    2017-05-01

    With the popularity of electric vehicles (EVs), such as plug-in electric vehicles (PHEVs) and battery electric vehicles (BEVs), an optimal strategy for the coordination of BEVs charging is proposed in this paper. The proposed approach incorporates the random behaviours and regular behaviours of BEV drivers in urban environment. These behaviours lead to the stochastic nature of the charging demand. The optimal strategy is used to guide the coordinated charging at different time to maximize the efficiency of virtual power plant (VPP). An innovative peer-to-peer system is used with BEVs to achieve the goals. The actual behaviours of vehicles in a campus is used to validate the proposed approach, and the simulation results show that the optimal strategy can not only maximize the utilization ratio of efficiency power plant, but also do not need additional energies from distribution grid.

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

    PubMed

    Wu, Zheyang; Zhao, Hongyu

    2009-07-01

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

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

    NASA Astrophysics Data System (ADS)

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

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

  9. Adjacency Matrix-Based Transmit Power Allocation Strategies in Wireless Sensor Networks

    PubMed Central

    Consolini, Luca; Medagliani, Paolo; Ferrari, Gianluigi

    2009-01-01

    In this paper, we present an innovative transmit power control scheme, based on optimization theory, for wireless sensor networks (WSNs) which use carrier sense multiple access (CSMA) with collision avoidance (CA) as medium access control (MAC) protocol. In particular, we focus on schemes where several remote nodes send data directly to a common access point (AP). Under the assumption of finite overall network transmit power and low traffic load, we derive the optimal transmit power allocation strategy that minimizes the packet error rate (PER) at the AP. This approach is based on modeling the CSMA/CA MAC protocol through a finite state machine and takes into account the network adjacency matrix, depending on the transmit power distribution and determining the network connectivity. It will be then shown that the transmit power allocation problem reduces to a convex constrained minimization problem. Our results show that, under the assumption of low traffic load, the power allocation strategy, which guarantees minimal delay, requires the maximization of network connectivity, which can be equivalently interpreted as the maximization of the number of non-zero entries of the adjacency matrix. The obtained theoretical results are confirmed by simulations for unslotted Zigbee WSNs. PMID:22346705

  10. Adjacency matrix-based transmit power allocation strategies in wireless sensor networks.

    PubMed

    Consolini, Luca; Medagliani, Paolo; Ferrari, Gianluigi

    2009-01-01

    In this paper, we present an innovative transmit power control scheme, based on optimization theory, for wireless sensor networks (WSNs) which use carrier sense multiple access (CSMA) with collision avoidance (CA) as medium access control (MAC) protocol. In particular, we focus on schemes where several remote nodes send data directly to a common access point (AP). Under the assumption of finite overall network transmit power and low traffic load, we derive the optimal transmit power allocation strategy that minimizes the packet error rate (PER) at the AP. This approach is based on modeling the CSMA/CA MAC protocol through a finite state machine and takes into account the network adjacency matrix, depending on the transmit power distribution and determining the network connectivity. It will be then shown that the transmit power allocation problem reduces to a convex constrained minimization problem. Our results show that, under the assumption of low traffic load, the power allocation strategy, which guarantees minimal delay, requires the maximization of network connectivity, which can be equivalently interpreted as the maximization of the number of non-zero entries of the adjacency matrix. The obtained theoretical results are confirmed by simulations for unslotted Zigbee WSNs.

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

    SciTech Connect

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

    2006-04-01

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

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

    SciTech Connect

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

    2006-04-01

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

  13. 77 FR 69819 - QC Power Strategies Fund LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-21

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF ENERGY Federal Energy Regulatory Commission QC Power Strategies Fund LLC; Supplemental Notice That Initial Market... in the above-referenced proceeding, of QC Power Strategies Fund LLC's application for market-based...

  14. An Exploration of Upper-Intermediate Iranian EFL Learners' Perception of Politeness Strategies and Power Relation in Disagreement

    ERIC Educational Resources Information Center

    Niroomand, Masoumeh

    2012-01-01

    The present study was designed to examine the ways power relations influence politeness strategies in disagreement. The study was an attempt to find out whether different power status of people influences the the choice of appropriate politeness strategies and speech act of disagreement by Iranian EFL learners, in a university setting. A Discourse…

  15. The Power Card Strategy: Strength-Based Intervention to Increase Direction Following of Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Campbell, Abbi; Tincani, Matt

    2011-01-01

    The Power Card strategy is a strength-based intervention to promote social skills of children with autism spectrum disorders (ASD) by capitalizing on their special interests. Although preliminary studies have shown that the Power Card strategy is a promising approach to teach social skills, additional research is needed. The purpose of this study…

  16. The Power Card Strategy: Strength-Based Intervention to Increase Direction Following of Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Campbell, Abbi; Tincani, Matt

    2011-01-01

    The Power Card strategy is a strength-based intervention to promote social skills of children with autism spectrum disorders (ASD) by capitalizing on their special interests. Although preliminary studies have shown that the Power Card strategy is a promising approach to teach social skills, additional research is needed. The purpose of this study…

  17. Analysis of R&D Strategy for Advanced Combined Cycle Power Systems

    NASA Astrophysics Data System (ADS)

    Akimoto, Keigo; Hayashi, Ayami; Kosugi, Takanobu; Tomoda, Toshimasa

    This article analyzes and evaluates the R&D strategy for advanced power generation technologies, such as natural gas combined cycles, IGCCs (Integrated coal Gasification Combined Cycles), and large-scale fuel cell power generation systems with a mixed-integer programming model. The R&D processes are explicitly formulated in the model through GERT (Graphical Evaluation and Review Technique), and the data on each required time of R&D was collected through questionnaire surveys among the experts. The obtained cost-effective strategy incorporates the optimum investment allocation among the developments of various elemental technologies, and at the same time, it incorporates the least-cost expansion planning of power systems in Japan including other power generation technologies such as conventional coal, oil, and gas fired, and hydro and wind power. The simulation results show the selection of the cost-effective technology developments and the importance of the concentrated investments in them. For example, IGCC, which has a relatively high thermal efficiency, and LNG-CCs of the assumed two efficiencies are the cost-effective investment targets in the no-CO2-regulation case.

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

    NASA Astrophysics Data System (ADS)

    Liu, Xuan

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

  19. Modeling the conversion of hydroacoustic to seismic energy at island and continental margins: preliminary analysis of Ascension Island data

    SciTech Connect

    Harben, P.; Rodgers, A.

    1999-07-26

    -phase amplitudes. For this paper we will focus on validating the finite difference method for modeling T-phases in the ocean and land environments and on modeling T-phases observed by the May 1999 Ascension Island Experiment. A network of broadband seismometers on Ascension Island recorded a large number of offshore airgun shots. The shots occurred at all azimuths around the island and at ranges from 1-45 km. Measurements of signal amplitude and duration will be made to understand the variability of T-phase behavior on Ascension Island. The sensitivity to topographic slope and island structure will also be investigated.

  20. What Are the Most Powerful Immunogen Design Vaccine Strategies? A Structural Biologist's Perspective.

    PubMed

    Kwong, Peter D

    2017-02-03

    The ability of structure-based design to control the shape and reactivity-the atomic-level chemistry-of an immunogen argues for it being one of the "most powerful" immunogen-design strategies. But antigenic reactivity is only one of the properties required to induce a protective immune response. Here, a multidimensional approach is used to exemplify the enabling role atomic-level information can play in the development of immunogens against three viral pathogens, respiratory syncytial virus, influenza A virus, and human immunodeficiency virus (HIV), which have resisted standard approaches to vaccine development. Overall, structure-based strategies incorporating B-cell ontogenies and viral evasion mechanisms appear exceptionally powerful. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

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

    SciTech Connect

    Zhang, Peng; Lee, Hyunsuk; Lee, Deokjung

    2016-01-15

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

  2. American Primacy and Major Power Concert: A Critique of the 2002 National Security Strategy

    DTIC Science & Technology

    2002-12-01

    thinking. It seemed wise to be patient in issuing a report, with the hope that time would bring a settling of major power relations and also clearer...international political landscape after the Cold War. They also described an America fixated on military means and tone deaf about politics. In the... dumbed down to the lowest common denominator, and we can’t afford 71 National Security Strategy, p

  3. Resistance Training Using Different Hypoxic Training Strategies: a Basis for Hypertrophy and Muscle Power Development.

    PubMed

    Feriche, Belén; García-Ramos, Amador; Morales-Artacho, Antonio J; Padial, Paulino

    2017-12-01

    The possible muscular strength, hypertrophy, and muscle power benefits of resistance training under environmental conditions of hypoxia are currently being investigated.Nowadays, resistance training in hypoxia constitutes a promising new training strategy for strength and muscle gains. The main mechanisms responsible for these effects seem to be related to increased metabolite accumulation due to hypoxia. However, no data are reported in the literature to describe and compare the efficacy of the different hypertrophic resistance training strategies in hypoxia.Moreover, improvements in sprinting, jumping, or throwing performance have also been described at terrestrial altitude, encouraging research into the speed of explosive movements at altitude. It has been suggested that the reduction in the aerodynamic resistance and/or the increase in the anaerobic metabolism at higher altitudes can influence the metabolic cost, increase the take-off velocities, or improve the motor unit recruitment patterns, which may explain these improvements. Despite these findings, the applicability of altitude conditions in improving muscle power by resistance training remains to be clarified.This review examines current knowledge regarding resistance training in different types of hypoxia, focusing on strategies designed to improve muscle hypertrophy as well as power for explosive movements.

  4. Visual Search Strategies of Soccer Players Executing a Power vs. Placement Penalty Kick

    PubMed Central

    Timmis, Matthew A.; Turner, Kieran; van Paridon, Kjell N.

    2014-01-01

    Introduction When taking a soccer penalty kick, there are two distinct kicking techniques that can be adopted; a ‘power’ penalty or a ‘placement’ penalty. The current study investigated how the type of penalty kick being taken affected the kicker’s visual search strategy and where the ball hit the goal (end ball location). Method Wearing a portable eye tracker, 12 university footballers executed 2 power and placement penalty kicks, indoors, both with and without the presence of a goalkeeper. Video cameras were used to determine initial ball velocity and end ball location. Results When taking the power penalty, the football was kicked significantly harder and more centrally in the goal compared to the placement penalty. During the power penalty, players fixated on the football for longer and more often at the goalkeeper (and by implication the middle of the goal), whereas in the placement penalty, fixated longer at the goal, specifically the edges. Findings remained consistent irrespective of goalkeeper presence. Discussion/conclusion Findings indicate differences in visual search strategy and end ball location as a function of type of penalty kick. When taking the placement penalty, players fixated and kicked the football to the edges of the goal in an attempt to direct the ball to an area that the goalkeeper would have difficulty reaching and saving. Fixating significantly longer on the football when taking the power compared to placement penalty indicates a greater importance of obtaining visual information from the football. This can be attributed to ensuring accurate foot-to-ball contact and subsequent generation of ball velocity. Aligning gaze and kicking the football centrally in the goal when executing the power compared to placement penalty may have been a strategy to reduce the risk of kicking wide of the goal altogether. PMID:25517405

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

    NASA Astrophysics Data System (ADS)

    Zhang, Peng; Lee, Hyunsuk; Lee, Deokjung

    2016-01-01

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

  6. Physiology, power output, and racing strategy of a Race Across America finisher.

    PubMed

    Schumacher, Yorck Olaf; Ahlgrim, Christoph; Prettin, Stephan; Pottgiesser, Torben

    2011-05-01

    The Race Across America, a 4800-km nonstop cycle race, is one of the most demanding endurance sports events. We display the racing strategy, power output, HR, hormonal levels, and inflammatory markers of an athlete before and during the race, which he completed in 10 d 23 h.The athlete showed physiological characteristics of a well-trained (nonelite) cyclist (V˙O2peak=63 mL·min·kg, heart volume=11.3 mL·kg). The race was mainly performed at low intensities (mean ± SD: power output=141 ± 76 W, HR=117 ± 14 bpm). During the race, testosterone levels dropped initially by 30-40% and returned to baseline toward the end. Cortisol remained elevated throughout (+75%-90% compared with baseline). Markers of inflammation (C-reactive protein), dehydration, and protein catabolism (albumin) were not affected. The athlete used a race strategy with regular sleeping breaks (total rest=91 h, 45 h of sleep).Contrasting conventional racing strategies for the Race Across America, which aim at minimizing sleep and maximizing ride time, our case demonstrates that by emphasizing regular recovery and sleep, such alternative strategy might lead an equally successful race result. © 2011 by the American College of Sports Medicine

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

    NASA Astrophysics Data System (ADS)

    Puers, R.; Carta, R.; Thoné, J.

    2011-05-01

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

  8. Power Strategy in DC/DC Converters to Increase Efficiency of Electrical Stimulators

    PubMed Central

    Aqueveque, Pablo; Acuña, Vicente; Saavedra, Francisco; Debelle, Adrien; Lonys, Laurent; Julémont, Nicolas; Huberland, François; Godfraind, Carmen; Nonclercq, Antoine

    2016-01-01

    Power efficiency is critical for electrical stimulators. Battery life of wearable stimulators and wireless power transmission in implanted systems are common limiting factors. Boost DC/DC converters are typically needed to increase the supply voltage of the output stage. Traditionally, boost DC/DC converters are used with fast control to regulate the supply voltage of the output. However, since stimulators are acting as current sources, such voltage regulation is not needed. Banking on this, this paper presents a DC/DC conversion strategy aiming to increase power efficiency. It compares, in terms of efficiency, the traditional use of boost converters to two alternatives that could be implemented in future hardware designs. PMID:27990232

  9. Insecticide treated bednet strategy in rural settings: can we exploit women's decision making power?

    PubMed

    Tilak, Rina; Tilak, V W; Bhalwar, R

    2007-01-01

    Use of insecticide treated bednets in prevention of malaria is a widely propagated global strategy, however, its use has been reported to be influenced and limited by many variables especially gender bias. A cross sectional field epidemiological study was conducted in a rural setting with two outcome variables, 'Bednet use'(primary outcome variable) and 'Women's Decision Making Power' which were studied in reference to various predictor variables. Analysis reveals a significant effect on the primary outcome variable 'Bednet use' of the predictor variables- age, occupation, bednet purchase decision, women's decision making power, husband's education and knowledge about malaria and its prevention. The study recommends IEC on treated bednets to be disseminated through TV targeting the elderly women who have better decision making power and mobilizing younger women who were found to prefer bednets for prevention of mosquito bites for optimizing the use of treated bednets in similar settings.

  10. Combined heat and power in the draft of the new Russian energy strategy

    NASA Astrophysics Data System (ADS)

    Makarova, A. S.; Pankrushina, T. G.; Urvantseva, L. V.; Khorshev, A. A.

    2015-06-01

    Comparison of combined heat and power development trends in Russia and other countries allowed us to assess world CHP development trends for different regions of Russia. The paper presents a methodological approach to a comprehensive assessment of the effectiveness and extent of the CHP development proposed by ERI RAS. This approach is based on a unified representation of both energy consumption of all Russian cities and the sources of their supply. In addition, combined heat and power is considered in a complex relationship with other types of power generators and fuel industries. The applicability of this approach for the study of the development prospects of diverse CHP plants was shown. The presented methodical approach was used to develop draft scenarios of the Energy Strategy of Russia until 2035. The performed assessment of preferred application areas and effective extent of CHP development indicated the reasonability of continuing growth of CHP capacity and their role in the district heating system in Russia.

  11. Ascension Patterns and Experiences of Past and Present Female Trustee Board Chairpersons at Independent Colleges and Universities in a Southern State

    ERIC Educational Resources Information Center

    Ricks Scott, Heather Inez

    2010-01-01

    The purpose of this study was to examine the ascension patterns and experiences of past and present female board of trustee chairpersons at independent institutions in a southeastern state. Although females continue to account for more of the college student population and obtain more degrees than males, females are severely underrepresented in…

  12. Enhanced IGCC regulatory control and coordinated plant-wide control strategies for improving power ramp rates

    SciTech Connect

    Mahapatra, P.; Zitney, S.

    2012-01-01

    As part of ongoing R&D activities at the National Energy Technology Laboratory’s (NETL) Advanced Virtual Energy Simulation Training & Research (AVESTAR™) Center, this paper highlights strategies for enhancing low-level regulatory control and system-wide coordinated control strategies implemented in a high-fidelity dynamic simulator for an Integrated Gasification Combined Cycle (IGCC) power plant with carbon capture. The underlying IGCC plant dynamic model contains 20 major process areas, each of which is tightly integrated with the rest of the power plant, making individual functionally-independent processes prone to routine disturbances. Single-loop feedback control although adequate to meet the primary control objective for most processes, does not take into account in advance the effect of these disturbances, making the entire power plant undergo large offshoots and/or oscillations before the feedback action has an opportunity to impact control performance. In this paper, controller enhancements ranging from retuning feedback control loops, multiplicative feed-forward control and other control techniques such as split-range control, feedback trim and dynamic compensation, applicable on various subsections of the integrated IGCC plant, have been highlighted and improvements in control responses have been given. Compared to using classical feedback-based control structure, the enhanced IGCC regulatory control architecture reduces plant settling time and peak offshoots, achieves faster disturbance rejection, and promotes higher power ramp-rates. In addition, improvements in IGCC coordinated plant-wide control strategies for “Gasifier-Lead”, “GT-Lead” and “Plantwide” operation modes have been proposed and their responses compared. The paper is concluded with a brief discussion on the potential IGCC controller improvements resulting from using advanced process control, including model predictive control (MPC), as a supervisory control layer.

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

    NASA Astrophysics Data System (ADS)

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

    2017-06-01

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

  14. Development and commercialization strategy for piezoelectric energy-harvesting power sources for gun-fired munitions

    NASA Astrophysics Data System (ADS)

    Rastegar, J.; Murray, R.

    2010-04-01

    A novel class of piezoelectric-based energy-harvesting power sources has been developed for gun-fired munitions and similar high-G applications. The power sources are designed to harvest energy primarily from the firing acceleration, but from in-flight vibratory motions as well. During the firing, a spring-mass element reacts to the axial acceleration, deforming and storing mechanical potential energy. After the projectile has exited the muzzle, the spring-mass element is free to vibrate, and the energy of the vibration is harvested using piezoelectric materials. These piezoelectric-based devices have been shown to produce enough electrical energy for many applications such as fuzing, and are able to eliminate the need for chemical batteries in many applications. When employed in fuzing applications, the developed power sources have the added advantage of providing augmented safety, since the fuzing electronics are powered only after the projectile has exited the muzzle and traveled a safe distance from the weapon platform. An overview of the development of these novel power sources is provided, especially designing and packaging for the high-G environment. Extensive laboratory and field testing has been performed on various prototypes; the methods and results of these experiments are presented. In addition to presenting the development and validation of this technology, methods for integrating the generators into different classes of projectiles are discussed along with strategies for manufacturing. This technology is currently validated to the extent that prototype devices have been successfully fired on-board actual gun-fired projectiles, demonstrating survivability and indicating performance. Strategies for designing the devices for a particular round and transitioning to commercialization are also discussed.

  15. Nucléation, ascension et éclatement d'une bulle de champagne

    NASA Astrophysics Data System (ADS)

    Liger-Belair, G.

    2006-03-01

    trains de bulles ainsi qu'à la détermination de la vitesse ascensionnelle des bulles. Les mesures expérimentales du rayon et de la vitesse d'une bulle nous ont permis de déterminer le coefficient de traînée d'une bulle montante qui constitue une mesure indirecte de son état de surface en termes de mobilité interfaciale. Ces mesures nous ont montré que l'interface d'une bulle de champagne conserve une grande mobilité interfaciale pendant sa phase ascensionnelle, à la différence des bulles de taille fixe qui montent dans une solution de macromolécules tensioactives. C'est la faible dilution du champagne en macromolécules tensioactives et le grossissement continu des bulles pendant l'ascension qui assurent aux bulles une faible contamination de leur interface. Pour comparaison, nous avons réalisé le même type de mesures sur des bulles de bière. Le contenu en macromolécules tensioactives étant beaucoup plus important dans une bière, l'effet de dilution du matériel tensioactif à la surface des bulles lié à l'accroissement de la surface des bulles ne compense plus l'adsorption massive des tensioactifs à la surface des bulles. Contrairement aux bulles du champagne, les bulles de bière adoptent vite un comportement de type sphère rigide. Nous avons également discuté l'influence relative de certains paramètres sur la taille des bulles lorsqu'elles parviennent en surface. Il a notamment été montré que le rôle théorique joué par la température du champagne sur la taille des bulles est quasiment négligeable. Pour finir, nous avons proposé d'essayer de faire du train de bulles une sorte d'empreinte digitale du liquide effervescent dans lequel il évolue en analysant la dynamique ascensionnelle des bulles via la mesure de leur coefficient de frottement. Nous avons pu différencier à ce jour par cette méthode trois grandes familles de boissons gazeuses : les vins effervescents au sens large (champagne compris), les bières et les eaux gazeuses

  16. Strategy for advancement of IRP in public power, Volume 2: Technical appendices

    SciTech Connect

    Garrick, C.J.

    1995-10-01

    NREL and subcontractor Garrick & Associates are conducting the Advancement of integrated resource planning (IRP) in Public Power Program, sponsored by DOE. The program is intended to develop a consistent strategy for DOE to advance IRP practices in the publicly and cooperatively owned utility sector. The IRP advancement program includes two major tasks: key participant involvement and strategy development. The Program`s initial task is to involve key public and cooperative utility organizations and their constituents in the development of the IRP advancement strategy. Key Participant Involvement is accomplished through two distinct subtasks: Needs Assessment and Steering Committee Involvement. The Needs Assessment identifies key participant needs, expectations, common interests, issues, and divergences that must be addressed by the IRP program. The results of this effort, which are presented in this {open_quotes}Needs Assessment Summary Report,{close_quotes} provide a foundation for the specific strategy development efforts conducted later in the IRP project. The remaining sections of this report present the approach to the Needs Assessment subtask and summarize the findings of this effort.

  17. Evaluation of different operating strategies to integrate storage in a linear Fresnel ORC power plant

    NASA Astrophysics Data System (ADS)

    Zoschke, Theda; Seubert, Bernhard; Fluri, Thomas

    2017-06-01

    An existing linear Fresnel power plant with ORC process located in Ben Guerir, Morocco, is retrofitted with a thermal energy storage system and additional collector loops. Two different plant configurations are investigated in this paper. In the first configuration two separate solar fields are built and only the minor one can charge the storage. In the second configuration, there is only one large solar field which offers more flexibility. Two different control strategies are assessed by comparing simulation results. It shows that the simulations of the systems with two solar fields results in higher energy yields throughout the year, but the power production of the system with one solar field is much more flexible and demand oriented. Also it offers great potential for improvement when it comes to weather forecasting.

  18. Optimization Strategy of Distortion Rate Control for High Power Transfer Supplying an X-Ray Tube

    NASA Astrophysics Data System (ADS)

    Mohamed, Rachedi; Mohamed, Bourahla

    2012-03-01

    This paper mainly concerns a contribution in the art development of high power generator supplying an X-ray tube for medical use. A generic method is proposed to reduce thermal stresses induced in X-ray tube during successive doses. For such application resonant DC-DC converter should be required, which generate output voltage and load current strictly identical to reference signal accompanied with normalized power factor quality. Primordially an adequate structure active filter connected in parallel at load lover is used to adjust the input and out put current distortion rate. With fuzzy logic control strategy, out put characteristics in transient and steady state are integrally mastery. This robust control type permits successive and repetitive taken measurement of radiology.

  19. Design strategies for ultra-low power 10 nm FinFETs

    NASA Astrophysics Data System (ADS)

    Walke, Abhijeet; Schlenvogt, Garrett; Kurinec, Santosh

    2017-10-01

    In this work, new design strategies for 10 nm node NMOS bulk FinFET transistors are investigated to meet low power (LP) (20 pA/μm < IOFF < 50 pA/μm) and ultralow power (ULP) (IOFF < 20 pA/μm) requirements using three dimensional (3D) TCAD simulations. The punch-through stop implant, source and drain junction placement and gate workfunction are varied in order to study the impact on the OFF-state current (IOFF), transconductance (gm), gate capacitance (Cgg) and intrinsic frequency (fT). It is shown that the gate length of 20 nm for the 10 nm node FinFET can meet the requirements of LP transistors and ULP transistors by source-drain extension engineering, punch-through stop doping concentration, and choice of gate workfunction.

  20. Observations of ozone formation in power plant plumes and implications for ozone control strategies.

    PubMed

    Ryerson, T B; Trainer, M; Holloway, J S; Parrish, D D; Huey, L G; Sueper, D T; Frost, G J; Donnelly, S G; Schauffler, S; Atlas, E L; Kuster, W C; Goldan, P D; Hubler, G; Meagher, J F; Fehsenfeld, F C

    2001-04-27

    Data taken in aircraft transects of emissions plumes from rural U.S. coal-fired power plants were used to confirm and quantify the nonlinear dependence of tropospheric ozone formation on plume NO(x) (NO plus NO(2)) concentration, which is determined by plant NO(x) emission rate and atmospheric dispersion. The ambient availability of reactive volatile organic compounds, principally biogenic isoprene, was also found to modulate ozone production rate and yield in these rural plumes. Differences of a factor of 2 or greater in plume ozone formation rates and yields as a function of NO(x) and volatile organic compound concentrations were consistently observed. These large differences suggest that consideration of power plant NO(x) emission rates and geographic locations in current and future U.S. ozone control strategies could substantially enhance the efficacy of NO(x) reductions from these sources.

  1. Study on Stochastic Optimal Electric Power Procurement Strategies with Uncertain Market Prices

    NASA Astrophysics Data System (ADS)

    Sakchai, Siripatanakulkhajorn; Saisho, Yuichi; Fujii, Yasumasa; Yamaji, Kenji

    The player in deregulated electricity markets can be categorized into three groups of GENCO (Generator Companies), TRNASCO (Transmission Companies), DISCO (Distribution Companies). This research focuses on the role of Distribution Companies, which purchase electricity from market at randomly fluctuating prices, and provide it to their customers at given fixed prices. Therefore Distribution companies have to take the risk stemming from price fluctuation of electricity instead of the customers. This entails the necessity to develop a certain method to make an optimal strategy for electricity procurement. In such a circumstance, this research has the purpose for proposing the mathematical method based on stochastic dynamic programming to evaluate the value of a long-term bilateral contract of electricity trade, and also a project of combination of the bilateral contract and power generation with their own generators for procuring electric power in deregulated market.

  2. Study of a control strategy for grid side converter in doubly- fed wind power system

    NASA Astrophysics Data System (ADS)

    Zhu, D. J.; Tan, Z. L.; Yuan, F.; Wang, Q. Y.; Ding, M.

    2016-08-01

    The grid side converter is an important part of the excitation system of doubly-fed asynchronous generator used in wind power system. As a three-phase voltage source PWM converter, it can not only transfer slip power in the form of active power, but also adjust the reactive power of the grid. This paper proposed a control approach for improving its performance. In this control approach, the dc voltage is regulated by a sliding mode variable structure control scheme and current by a variable structure controller based on the input output linearization. The theoretical bases of the sliding mode variable structure control were introduced, and the stability proof was presented. Switching function of the system has been deduced, sliding mode voltage controller model has been established, and the output of the outer voltage loop is the instruction of the inner current loop. Affine nonlinear model of two input two output equations on d-q axis for current has been established its meeting conditions of exact linearization were proved. In order to improve the anti-jamming capability of the system, a variable structure control was added in the current controller, the control law was deduced. The dual-loop control with sliding mode control in outer voltage loop and linearization variable structure control in inner current loop was proposed. Simulation results demonstrate the effectiveness of the proposed control strategy even during the dc reference voltage and system load variation.

  3. Improving power to detect disease progression in multiple sclerosis through alternative analysis strategies.

    PubMed

    Healy, Brian; Chitnis, Tanuja; Engler, David

    2011-10-01

    In patients with multiple sclerosis, investigation of a treatment effect on disease progression in clinical trials and observational studies often uses sustained progression on the expanded disability status scale (EDSS) as an outcome. It is not clear whether this outcome is the most powerful to detect a treatment effect on clinical disease progression. Assessment of EDSS modeling choice on the detection of treatment effect was of interest. This assessment was separately conducted under three potential treatment effects: treatment reducing the chance of higher future EDSS, treatment increasing the chance of lower future EDSS, and treatment leading to both effects. To assess the effect of modeling choice, nine modeling strategies were applied to the data to determine the most powerful approach. EDSS measurements were simulated at 6 month intervals for 24 months. Each patient's initial EDSS value ranged between 0 and 3, and probabilities of transitioning from one EDSS state to another were based on the empirical probabilities of transition obtained from available clinical data. Modeling approaches based on sustained progression had less power than approaches which modeled the EDSS score directly, regardless of treatment effect. This difference was especially pronounced when the treatment effect corresponded to an increase in the probability of improvement. Sustained progression on the EDSS is a less powerful outcome measure for clinical progression than approaches based on the actual EDSS values.

  4. Potential impacts from tephra fall to electric power systems: a review and mitigation strategies

    NASA Astrophysics Data System (ADS)

    Wardman, J. B.; Wilson, T. M.; Bodger, P. S.; Cole, J. W.; Stewart, C.

    2012-12-01

    Modern society is highly dependent on a reliable electricity supply. During explosive volcanic eruptions, tephra contamination of power networks (systems) can compromise the reliability of supply. Outages can have significant cascading impacts for other critical infrastructure sectors and for society as a whole. This paper summarises known impacts to power systems following tephra falls since 1980. The main impacts are (1) supply outages from insulator flashover caused by tephra contamination, (2) disruption of generation facilities, (3) controlled outages during tephra cleaning, (4) abrasion and corrosion of exposed equipment and (5) line (conductor) breakage due to tephra loading. Of these impacts, insulator flashover is the most common disruption. The review highlights multiple instances of electric power systems exhibiting tolerance to tephra falls, suggesting that failure thresholds exist and should be identified to avoid future unplanned interruptions. To address this need, we have produced a fragility function that quantifies the likelihood of insulator flashover at different thicknesses of tephra. Finally, based on our review of case studies, potential mitigation strategies are summarised. Specifically, avoiding tephra-induced insulator flashover by cleaning key facilities such as generation sites and transmission and distribution substations is of critical importance in maintaining the integrity of an electric power system.

  5. FERMI magnet power supplies: design strategies and five years of operational experience

    NASA Astrophysics Data System (ADS)

    Visintini, Roberto

    2015-05-01

    FERMI is the FEL-based light source in operation for external users since 2011 at the Elettra Research Center in Trieste, Italy. FERMI@Elettra is the name of the project for the construction and commissioning of this source. The design strategies adopted in the project had to consider the extremely close presence and the routine operation for users of the synchrotron-based source Elettra. There are more than 350 magnets and coils distributed along the linear accelerator, the two chains of undulators and the electron beam dump. Almost each magnetic element requires a dedicated DC power supply. Magnets, power supplies, and the connecting cables constitute a system, strongly interconnected with the remote control system, the machine and personnel safety system, and the infrastructure. All this has to fulfill the requirements from the particle physics specialists. We adopted a "systemic" approach in the design of new magnets and the re-use of the old ones, as well as the choice and the design of the associated power supplies. The commissioning of the systems started early 2010 and almost all magnet power supplies are in operation since then. During these 5 years, we introduced few minor upgrades and patches while the adopted solutions proved their soundness in terms of performance and reliability, causing very little downtime to the FERMI operations.

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

    PubMed

    Kailas, Aravind

    2011-01-01

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

  7. Power Allocation Strategies for Distributed Space-Time Codes in Amplify-and-Forward Mode

    NASA Astrophysics Data System (ADS)

    Maham, Behrouz; Hjørungnes, Are

    2009-12-01

    We consider a wireless relay network with Rayleigh fading channels and apply distributed space-time coding (DSTC) in amplify-and-forward (AF) mode. It is assumed that the relays have statistical channel state information (CSI) of the local source-relay channels, while the destination has full instantaneous CSI of the channels. It turns out that, combined with the minimum SNR based power allocation in the relays, AF DSTC results in a new opportunistic relaying scheme, in which the best relay is selected to retransmit the source's signal. Furthermore, we have derived the optimum power allocation between two cooperative transmission phases by maximizing the average received SNR at the destination. Next, assuming M-PSK and M-QAM modulations, we analyze the performance of cooperative diversity wireless networks using AF opportunistic relaying. We also derive an approximate formula for the symbol error rate (SER) of AF DSTC. Assuming the use of full-diversity space-time codes, we derive two power allocation strategies minimizing the approximate SER expressions, for constrained transmit power. Our analytical results have been confirmed by simulation results, using full-rate, full-diversity distributed space-time codes.

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

    NASA Astrophysics Data System (ADS)

    Yu, Xunwei

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

  9. Effect of heating strategy on power consumption and performance of a pilot plant anaerobic digester.

    PubMed

    Espinosa-Solares, Teodoro; Valle-Guadarrama, Salvador; Bombardiere, John; Domaschko, Max; Easter, Michael

    2009-05-01

    The effect of heating strategy on power consumption and performance of a pilot plant anaerobic digester treating chicken litter, under thermophilic conditions, has been studied. Heating strategy was evaluated using three different spans (0.2 degrees C, 0.6 degrees C, and 1.0 degree C) for triggering the temperature control system from target temperature (56.7 degrees C). The hydraulic retention time in the pilot plant digester was in the range of 32 to 37 days, varying the total solids concentration fed from 5% to 6%. The results showed that under the experimental conditions, heating was the most energy-demanding process with 95.5% of the energy used. Increments up to 7.5% and 3.8%, respectively, on mechanical and heating power consumption, were observed as the span, for triggering the temperature control system from target temperature, was increased. Under the experimental conditions studied here, an increment of 30.6% on the global biodigester performance index was observed when a span of 1.0 degree C was compared to the one of 0.2 degrees C.

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

    NASA Astrophysics Data System (ADS)

    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.

  11. Development strategies on an integrated operator decision aid support system for nuclear power plants

    SciTech Connect

    Ki Sig Kang; Han Gon Kim; Soon Heung Chang . Dept of Nuclear Engineering); Jeong, Hee Kyo; Park, S.D.

    1993-08-01

    The development strategies on an integrated operator decision aid support (IODAS) system are discussed by focusing attention on the importance of the operator's role for nuclear power plants. The IODAS is under development to support the operator's decision making process and to enhance the safety of a nuclear power plant by providing the plant operators with timely and proper guideline during abnormal and emergency conditions. The IODAS has capabilities for the signal validation/management, the alarm processing, the failure diagnosis using abnormal operating procedures, and the dynamic tracking of emergency operating procedures using function restoration guidelines and optimal recovery guidelines with a series of complex logic steps covering a broad spectrum of event sequences. The proposed system is being implemented on a SUN-4/75 Workstation using C and Quintus[sup TM] prolog language. For verification studies a full-scope real-time simulator is being used. Test results show that the IODAS is capable of diagnosing a plant failure quickly and of providing an operator guideline with fast response time. After verification, the IODAS will be installed in the main control room of the unit one nuclear power plant at Yeoung Gwang.

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

    NASA Technical Reports Server (NTRS)

    Watson, Karen

    1990-01-01

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

  13. Coping with Stress and Types of Burnout: Explanatory Power of Different Coping Strategies

    PubMed Central

    Montero-Marin, Jesus; Prado-Abril, Javier; Piva Demarzo, Marcelo Marcos; Gascon, Santiago; García-Campayo, Javier

    2014-01-01

    Background Burnout occurs when professionals use ineffective coping strategies to try to protect themselves from work-related stress. The dimensions of ‘overload’, ‘lack of development’ and ‘neglect’, belonging to the ‘frenetic’, ‘under-challenged’ and ‘worn-out’ subtypes, respectively, comprise a brief typological definition of burnout. The aim of the present study was to estimate the explanatory power of the different coping strategies on the development of burnout subtypes. Methods This was a cross-sectional survey with a random sample of university employees, stratified by occupation (n = 429). Multivariate linear regression models were constructed between the ‘Burnout Clinical Subtypes Questionnaire’, with its three dimensions –overload, lack of development and neglect– as dependent variables, and the ‘Coping Orientation for Problem Experiences’, with its fifteen dimensions, as independent variables. Adjusted multiple determination coefficients and beta coefficients were calculated to evaluate and compare the explanatory capacity of the different coping strategies. Results The ‘Coping Orientation for Problem Experiences’ subscales together explained 15% of the ‘overload’ (p<0.001), 9% of the ‘lack of development’ (p<0.001), and 21% of the ‘neglect’ (p<0.001). ‘Overload’ was mainly explained by ‘venting of emotions’ (Beta = 0.34; p<0.001); ‘lack of development’ by ‘cognitive avoidance’ (Beta = 0.21; p<0.001); and ‘neglect’ by ‘behavioural disengagement’ (Beta = 0.40; p<0.001). Other interesting associations were observed. Conclusions These findings further our understanding of the way in which the effectiveness of interventions for burnout may be improved, by influencing new treatments and preventive programmes using features of the strategies for handling stress in the workplace. PMID:24551223

  14. Ascending in healthcare. Roman Catholic Ascension Health has made a Fortune 500 name for itself with business acumen, risk-taking and efficiency.

    PubMed

    Evans, Melanie

    2007-05-14

    In less than a decade, Ascension Health has risen to the top tier of U.S. healthcare systems, with operating revenue that bests household names like Google and Amazon.com. Helping lead the system's meteoric rise is CEO Anthony Tersigni, left. "We are a ministry. We're not a business. We do business practices for one basic reason: We have bondholders who are counting on us to repay the bonds."

  15. Adaptive Control for Buck Power Converter Using Fixed Point Inducting Control and Zero Average Dynamics Strategies

    NASA Astrophysics Data System (ADS)

    Hoyos Velasco, Fredy Edimer; García, Nicolás Toro; Garcés Gómez, Yeison Alberto

    In this paper, the output voltage of a buck power converter is controlled by means of a quasi-sliding scheme. The Fixed Point Inducting Control (FPIC) technique is used for the control design, based on the Zero Average Dynamics (ZAD) strategy, including load estimation by means of the Least Mean Squares (LMS) method. The control scheme is tested in a Rapid Control Prototyping (RCP) system based on Digital Signal Processing (DSP) for dSPACE platform. The closed loop system shows adequate performance. The experimental and simulation results match. The main contribution of this paper is to introduce the load estimator by means of LMS, to make ZAD and FPIC control feasible in load variation conditions. In addition, comparison results for controlled buck converter with SMC, PID and ZAD-FPIC control techniques are shown.

  16. Subsurface injection of combustion power plant effluent as a solid-phase carbon dioxide storage strategy

    NASA Astrophysics Data System (ADS)

    Darnell, K. N.; Flemings, P. B.; DiCarlo, D.

    2017-06-01

    Long-term geological storage of CO2 may be essential for greenhouse gas mitigation, so a number of storage strategies have been developed that utilize a variety of physical processes. Recent work shows that injection of combustion power plant effluent, a mixture of CO2 and N2, into CH4 hydrate-bearing reservoirs blends CO2 storage with simultaneous CH4 production where the CO2 is stored in hydrate, an immobile, solid compound. This strategy creates economic value from the CH4 production, reduces the preinjection complexity since costly CO2 distillation is circumvented, and limits leakage since hydrate is immobile. Here we explore the phase behavior of these types of injections and describe the individual roles of H2O, CO2, CH4, and N2 as these components partition into aqueous, vapor, hydrate, and liquid CO2 phases. Our results show that CO2 storage in subpermafrost or submarine hydrate-forming reservoirs requires coinjection of N2 to maintain two-phase flow and limit plugging.

  17. Xenon Acquisition Strategies for High-Power Electric Propulsion NASA Missions

    NASA Technical Reports Server (NTRS)

    Herman, Daniel A.; Unfried, Kenneth G.

    2015-01-01

    The benefits of high-power solar electric propulsion (SEP) for both NASA's human and science exploration missions combined with the technology investment from the Space Technology Mission Directorate have enabled the development of a 50kW-class SEP mission. NASA mission concepts developed, including the Asteroid Redirect Robotic Mission, and those proposed by contracted efforts for the 30kW-class demonstration have a range of xenon propellant loads from 100's of kg up to 10,000 kg. A xenon propellant load of 10 metric tons represents greater than 10% of the global annual production rate of xenon. A single procurement of this size with short-term delivery can disrupt the xenon market, driving up pricing, making the propellant costs for the mission prohibitive. This paper examines the status of the xenon industry worldwide, including historical xenon supply and pricing. The paper discusses approaches for acquiring on the order of 10 MT of xenon propellant considering realistic programmatic constraints to support potential near-term NASA missions. Finally, the paper will discuss acquisitions strategies for mission campaigns utilizing multiple high-power solar electric propulsion vehicles requiring 100's of metric tons of xenon over an extended period of time where a longer term acquisition approach could be implemented.

  18. General strategy for designing core-shell nanostructured materials for high-power lithium ion batteries.

    PubMed

    Shen, Laifa; Li, Hongsen; Uchaker, Evan; Zhang, Xiaogang; Cao, Guozhong

    2012-11-14

    Because of its extreme safety and outstanding cycle life, Li(4)Ti(5)O(12) has been regarded as one of the most promising anode materials for next-generation high-power lithium-ion batteries. Nevertheless, Li(4)Ti(5)O(12) suffers from poor electronic conductivity. Here, we develop a novel strategy for the fabrication of Li(4)Ti(5)O(12)/carbon core-shell electrodes using metal oxyacetyl acetonate as titania and single-source carbon. Importantly, this novel approach is simple and general, with which we have successfully produce nanosized particles of an olivine-type LiMPO(4) (M = Fe, Mn, and Co) core with a uniform carbon shell, one of the leading cathode materials for lithium-ion batteries. Metal acetylacetonates first decompose with carbon coating the particles, which is followed by a solid state reaction in the limited reaction area inside the carbon shell to produce the LTO/C (LMPO(4)/C) core-shell nanostructure. The optimum design of the core-shell nanostructures permits fast kinetics for both transported Li(+) ions and electrons, enabling high-power performance.

  19. Framework of systematic sustainability assessment strategy (FSSAS) for hydroelectric power industry in Malaysia

    NASA Astrophysics Data System (ADS)

    Johan, Kartina; Turan, Faiz Mohd

    2017-08-01

    Hydroelectric power is an alternative power resource in Malaysia and always associated with negative impact on environmental, social and economy of the surrounding site. The dispute over environmental, societal and economic issues can be minimised if compliance to sustainability development requirement is included in the project as part of the project premises during planning phase. This paper suggests a framework targeted for decision-makers in charge of implementing the projects to produce hydropower the sustainable way in Malaysian context which can mitigate the risks in social, environment and economy. The framework is strategic in nature and based on project management methodology with objective to provide a ‘common language’ by having a project value as measureable for stakeholders to state their mutual agreement of what a sustainable hydropower project in the context of Malaysia and in line with the United Nations (UN) 17 Sustainable Development Goals (SDGs). The paper discusses how the proposed systematic sustainability assessment strategy (FSSAS) framework support the call for Malaysia to promote meaningful public participation in ensuring land and natural resource decisions and to address citizens’ interests which is the core idea of Environmental Democracy Index established in 2014. The paper argues that, even though it is at present impossible to define precision status of sustainability development with respect to the nature of the multi stakeholders and the lack of systematic assessment the proposed FSSAS framework can be a valuable tool because it tracks the project value as a quantitative deliverable to determine the status of the journey in sustainable development towards accomplishing the SDG under a consensus in hydropower industry of any scale over time.

  20. Bimanual force control strategies in chronic stroke: finger extension versus power grip.

    PubMed

    Lodha, Neha; Patten, Carolynn; Coombes, Stephen A; Cauraugh, James H

    2012-09-01

    Stroke leads to motor asymmetries in the flexor and extensor muscles of the hand. Typically, the strength deficits in the extensors are greater than the flexors. The impact of differential motor abilities of these muscle groups on the execution of bimanual force control tasks in individuals with stroke is unknown. The primary purpose of this study was to determine the influence of task constraints on visually guided bimanual force control in chronic stroke. Stroke survivors and age-matched individuals performed bimanual isometric contractions for 20s to match target submaximal force levels. Online visual feedback of the total force (sum of the forces produced by both hands) was provided. The task constraints were manipulated by (a) finger extension, and (b) finger flexion (power grip). Force asymmetry was indexed by the proportion of force contributed by the paretic hand to the total force. The stroke group demonstrated task-specific asymmetry in bimanual force control. Specifically, the paretic hand contributed less force than the non-paretic hand in finger extension whereas this relationship was reversed in power grip. Importantly, regardless of the nature of the task, reduction in motor impairments was associated with increased symmetry and coordination in bimanual tasks. Further, bimanual submaximal grip force control revealed asymmetry and coordination deficits that are not identified by investigating bimanual maximal force production alone. The motor control strategy adopted to optimize performance on bimanual tasks revealed the altered force production of the paretic hand due to the combined effect of extensor weakness and enhanced flexor bias following stroke. Bimanual asymmetries in stroke survivors highlight the need for identifying and treating the task-specific impairments for maximizing motor recovery post stroke.

  1. Using System Dynamics to Define, Study, and Implement Smart Control Strategies on the Electric Power Grid

    SciTech Connect

    Lyle G. Roybal; Robert F Jeffers

    2013-07-01

    The United States electric power grid is the most complex and expansive control system in the world. Local generation control occurs at individual units based on response time and unit economics, larger regional control coordinates unit response to error conditions, and high level large-area regional control is ultimately administered by a network of humans guided by economic and resiliency related factors. Under normal operating conditions, the grid is a relatively slow moving entity that exhibits high inertia to outside stimuli, and behaves along repeatable diurnal and seasonal patterns. However, that paradigm is quickly changing because of the increasing implementation of renewable generation sources. Renewable generators by nature cannot be tightly controlled or scheduled. They appear like a negative load to the system with all of the variability associated with load on a larger scale. Also, grid-reactive loads (i.e. smart devices) can alter their consumption based on price or demand rules adding more variability to system behavior. This paper demonstrates how a systems dynamic modeling approach capable of operating over multiple time scales, can provide valuable insight into developing new “smart-grid” control strategies and devices needed to accommodate renewable generation and regulate the frequency of the grid.

  2. Anatomy of power system blackouts and preventive strategies by rational supervision and control of protection systems

    SciTech Connect

    Phadke, A.G.; Horowitz, S.H.; Thorp, J.S.

    1995-01-01

    This report establishes the concept of hidden failures in relays and associated devices used for the protection of electric power systems. A hidden failure is a defect such as a component failure, inappropriate setting or incorrect external connection that remains undetected until some other system event causes the hidden failure to initiate a cascading outage. Associated with the study of hidden failures, this report examines the impact such defects might have by defining regions of vulnerability. A region of vulnerability is the area of the system in which a hidden failure will be activated. To determine such areas we have established criteria associated with load flows and steady-state stability, such as lack of convergence, and employed a technique known as importance sampling in which the simulation is done with the probabilities altered so that the rare event happens more frequently. Our purpose is to provide a framework for further research into relay vulnerability, possibly using adaptive techniques to eliminate hidden defects. We believe control strategies can be developed to prevent cascading normal operations from developing into severe outages by extending the present criteria using steady-state stability and load flow studies into the area of transient stability, and further research into importance sampling would provide significant benefits in evaluating corrective actions.

  3. Strategy for Migration of Traditional to Hybrid Control Boards in a Nuclear Power Plant

    SciTech Connect

    Boring, Ronald Laurids; Joe, Jeffrey Clark; Ulrich, Thomas Anthony

    2014-07-01

    This strategy document describes the NUREG-0711 based human factors engineering (HFE) phases and associated elements required to support design, verification and validation (V&V), and implementation of new digital control room elements in a legacy analog main control room (MCR). Information from previous planning and analysis work serves as the foundation for creating a human-machine interface (HMI) specification for distributed control systems (DCSs) to be implemented as part of nuclear power plant (NPP) modernization. This document reviews ways to take the HMSI specification and use it when migrating legacy displays or designing displays with new functionality. These displays undergo iterative usability testing during the design phase and then an integrated system validation (ISV) in the full-scope control room training simulator. Following successful demonstration of operator performance using the systems during the ISV, the new DCS is implemented at the plant, first in the training simulator and then in the MCR. This document concludes with a sample project plan, including a 15-month timeline from DCS design through implementation. Included is a discussion of how the U.S. Department of Energy’s Human System Simulation Laboratory (HSSL) can be used to support design and V&V activities. This report completes a Level 4 (M4) milestone under the U.S. Department of Energy’s (DOE’s) Light Water Reactor Sustainability (LWRS) Program.

  4. An Investigation of Iranian EFL Learners' Use of Politeness Strategies and Power Relations in Disagreement across Different Proficiency Levels

    ERIC Educational Resources Information Center

    Behnam, Biook; Niroomand, Masoumeh

    2011-01-01

    The speech act of disagreement has been one of the speech acts that receives the least attention in the field of pragmatics. This study investigates the ways power relations influence politeness strategies in disagreement. In order to determine whether and to what extent the realization of the speech act of disagreeing and the of appropriate…

  5. Power and Liberty: A Long-Term Course Planning Strategy to Encourage the Contextualization of Events in American History

    ERIC Educational Resources Information Center

    Endacott, Jason L.

    2011-01-01

    Applying a consistent historical theme throughout a social studies course is an effective long-term planning strategy that can promote student engagement, retention of information, and contextualized knowledge of history's continuity and change. This article demonstrates how one such theme, power and liberty, might be incorporated into a secondary…

  6. Power and Liberty: A Long-Term Course Planning Strategy to Encourage the Contextualization of Events in American History

    ERIC Educational Resources Information Center

    Endacott, Jason L.

    2011-01-01

    Applying a consistent historical theme throughout a social studies course is an effective long-term planning strategy that can promote student engagement, retention of information, and contextualized knowledge of history's continuity and change. This article demonstrates how one such theme, power and liberty, might be incorporated into a secondary…

  7. Strategies to reduce the configuration time for a powered knee and ankle prosthesis across multiple ambulation modes.

    PubMed

    Simon, Ann M; Fey, Nicholas P; Finucane, Suzanne B; Lipschutz, Robert D; Hargrove, Levi J

    2013-06-01

    Recently developed powered lower limb prostheses allow users to more closely mimic the kinematics and kinetics of non-amputee gait. However, configuring such a device, in particular a combined powered knee and ankle, for individuals with a transfemoral amputation is challenging. Previous attempts have relied on empirical tuning of all control parameters. This paper describes modified stance phase control strategies - which mimic the behavior of biological joints or depend on the instantaneous loads within the prosthesis - developed to reduce the number of control parameters that require individual tuning. Three individuals with unilateral transfemoral amputations walked with a powered knee and ankle prosthesis across five ambulation modes (level ground walking, ramp ascent/descent, and stair ascent/descent). Starting with a nominal set of impedance parameters, the modified control strategies were applied and the devices were individually tuned such that all subjects achieved comfortable and safe ambulation. The control strategies drastically reduced the number of independent parameters that needed to be tuned for each subject (i.e., to 21 parameters instead of a possible 140 or approximately 4 parameters per mode) while relative amplitudes and timing of kinematic and kinetic data remained similar to those previously reported and to those of non-amputee subjects. Reducing the time necessary to configure a powered device across multiple ambulation modes may allow users to more quickly realize the benefits such powered devices can provide.

  8. Hydrogen and oxygen isotope geochemistry of Ascension Island lavas and granites: variation with crystal fractionation and interaction with sea water

    NASA Astrophysics Data System (ADS)

    Sheppard, Simon M. F.; Harris, Chris

    1985-09-01

    Lavas and pyroclastics on Ascension Island contain plutonic blocks that include fluid-inclusion-bearing peralkaline-granite. 18O/16O ratios, F and Cl have been analysed on whole rocks and/or minerals for lavas and granites, and D/H ratios and H2O+ for comenditic obsidians and granites. Whole rock 18O/16O ratios of fresh alkali-basalt, hawaiite, trachyandesite, trachyte and comendite range from 6.0 to 6.9‰ with 18O tending to increase with increase in SiO2. The δ 18O values of the granites are from 0.0 to 0.3‰ depleted in 18O relative to the comendites. Comenditic obsidians have δD= -80±4‰ and H2O+ ˜0.3 wt.% while amphiboles from the granites have δD= -56±2‰ The O-isotope trend of the lavas is consistent with a crystal fractionation model. Fresh igneous rocks with δ 18O values greater than 7‰ involve processes in addition to crystal fractionation of a basaltic magma. The D/H ratios and Cl contents (˜ 3,000 ppm) of the H2O-poor comenditic obsidians represent undegassed primary magmatic values. The H-isotope compositions and low H2O and Cl (167 ppm) contents of the granites are consistent with the major degassing (loss of >90% of initial H2O) of an H2Osaturated magma derived from the interaction of sea (or possibly meteoric) water with the H2O-undersaturated comenditic melt. It is proposed that, associated with caldera subsidence and stoping, water was sucked in around the residual magma before the system had time to be sealed up. The H2O-undersaturated magma consumed this H2O with possibly some minor partial dehydration and dewatering of the hydrated volcanic roof blocks, at a pressure of about 1.5 kb. The granites are the plutonic equivalents of rhyolitic pyroclastics and not directly of the comendites. Granites from oceanic islands may, in general, be a result of generating an H2O-saturated acid melt by such direct or indirect crustal water-magma interaction processes.

  9. Development of energy management system based on a power sharing strategy for a fuel cell-battery-supercapacitor hybrid tramway

    NASA Astrophysics Data System (ADS)

    Li, Qi; Chen, Weirong; Liu, Zhixiang; Li, Ming; Ma, Lei

    2015-04-01

    A hybrid powertrain configuration based on a proton exchange membrane (PEMFC), a battery and a supercapacitor (SC) is designed without grid connection for the LF-LRV tramway. In order to avoid rapid changes of power demand and achieve high efficiency without degrading the mechanism performance, a power sharing strategy based on a combination of fuzzy logic control (FLC) and Haar wavelet transform (Haar-WT) is proposed for an energy management system of the hybrid tramway. The results demonstrate that the proposed energy management system is able to ensure the major positive portion of the low frequency components of power demand can be deals with the PEMFC. The battery can help provide a portion of the positive low frequency components of power demand to reduce the PEMFC burden while the SC bank can supply all the high frequency components which could damage the PEMFC membrane. Therefore, the energy management system of high-power hybrid tramway is able to guarantee a safe operating condition with transient free for the PEMFC and extend the lifetime of each power source. Finally, the comparisons with other control strategies verify that the proposed energy management system can achieve better energy efficiency of the overall hybrid tramway.

  10. Strategies for the Use of Tidal Stream Currents for Power Generation

    NASA Astrophysics Data System (ADS)

    Orhan, Kadir; Mayerle, Roberto

    2015-04-01

    Indonesia is one of the priority countries in Southeast Asia for the development of ocean renewable energy facilities and The National Energy Council intends to increase the role of ocean energy significantly in the energy mix for 2010-2050. To this end, the joint German-Indonesian project "Ocean Renewable Energy ORE-12" aims at the identification of marine environments in the Indonesian Archipelago, which are suitable for the efficient generation of electric power by converter facilities. This study, within the ORE-12 project, is focused on the tidal stream currents on the straits between the Indian Ocean and Flores Sea to estimate the energy potentials and to develop strategies for producing renewable energy. FLOW module of Delft3D has been used to run hydrodynamic models for site assessment and design development. In site assessment phase, 2D models have been operated for a-month long periods and with a resolution of 500 m. Later on, in design development phase, detailed 3D models have been developed and operated for three-month long periods and with a resolution of 50 m. Bathymetric data for models have been obtained from the GEBCO_08 Grid and wind data from the Global Forecast System of NOAA's National Climatic Data Center. To set the boundary conditions of models, tidal forcing with 11 harmonic constituents was supplied from TPXO Indian Ocean Atlas (1/12° regional model) and data from HYCOM+NCODA Global 1/12° Analysis have been used to determine salinity and temperature on open boundaries. After the field survey is complete, water level time-series supplied from a tidal gauge located in the domain of interest (8° 20΄ 9.7" S, 122° 54΄ 51.9" E) have been used to verify the models and then energy potentials of the straits have been estimated. As a next step, correspondence between model outputs and measurements taken by the radar system of TerraSAR-X satellite (DLR) will be analysed. Also for the assessment of environmental impacts caused by tidal stream

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

    PubMed Central

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

    2017-01-01

    Objective Little is known about how strategies of retaining patients are acted out by general practitioners (GPs) in the clinical encounter. With this study, we apply Grimens’ (2009) analytical connection between trust and power to explore how trust and power appear in preventive health checks from the GPs’ perspectives, and in what way trust and power affect and/or challenge strategies towards retaining patients without formal education. Design Data in this study were obtained through semi-structured interviews with GPs participating in an intervention project, as well as observations of clinical encounters. Results From the empirical data, we identified three dimensions of respect: respect for the patient’s autonomy, respect for professional authority and respect as a mutual exchange. A balance of respect influenced trust in the relationship between GP and patients and the transfer of power in the encounter. The GPs articulated that a balance was needed in preventive health checks in order to establish trust and thus retain the patient in the clinic. One way this balance of respect was carried out was with the use of humour. Conclusions To retain patients without formal education in the clinical encounter, the GPs balanced trust and power executed through three dimensions of respect. In this study, retaining patients was equivalent to maintaining a trusting relationship. A strategic use of the three dimensions of respect was applied to balance trust and power and thus build or maintain a trusting relationship with patients. Key points Little is known about how strategies for retaining patients are acted out by GPs in preventive health checks. Retaining patients requires a balance of trust and power, which is executed through three dimensions of respect by the GPs.Challenges of recruiting and retaining patients in public health initiatives might be associated with the balance of respect. PMID:28277053

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

    PubMed

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

    2017-03-01

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

  13. An alternative strategy for low specific power reactors to power interplanetary spacecraft, based on exploiting lasers and lunar resources

    SciTech Connect

    Logan, B.G.

    1989-02-02

    A key requirement setting the minimum electric propulsion performance (specific power ..cap alpha../sub e/ = kW/sub e//kg) for manned missions to Mars is the maximum allowable radiation dose to the crew during the long transits between Earth and Mars. Penetrating galactic cosmic rays and secondary neutron showers give about 0.1-rem/day dose, which only massive shielding (e.g., a meter of concrete) can reduce significantly. With a humane allowance for cabin space, the shielding mass becomes so large that it prohibitively escalates the propellant consumption required for reasonable trip times. This paper covers various proposed methods for using reactor power to propel spacecraft. 7 refs., 6 figs., 1 tab.

  14. Condom use negotiation in heterosexual African American adults: responses to types of social power-based strategies.

    PubMed

    Otto-Salaj, Laura; Reed, Barbara; Brondino, Michael J; Gore-Felton, Cheryl; Kelly, Jeffrey A; Stevenson, L Yvonne

    2008-01-01

    This study examined gender differences and preferences in the use of and response to six different styles of condom use negotiation with a hypothetical sexual partner of the opposite gender. Participants were 51 heterosexually active African American adults attending an inner-city community center. Participants completed a semistructured qualitative interview in which they were presented with six negotiation strategies based on Raven's 1992 Power/Interaction Model of Interpersonal Influence. Results showed that female participants responded best to referent, reward, and legitimate strategies, and worst to informational tactics. Male participants responded best to reward strategies, and worst to coercion to use condoms. Further, responses given by a subset of participants indicated that use of negotiation tactics involving coercion to use condoms may result in negative or angry reactions. Response to strategies may vary with the value of the relationship as viewed by the target of negotiation. Implications for HIV prevention efforts are discussed.

  15. Solar Power Stations for Remote Sites: An Economic Analysis.

    DTIC Science & Technology

    1981-01-01

    From Ascension AAF 17 2 Average Daily Extraterrestial Radiation, MJ/m 2 26 3 Capital Cost Breakdown, Annual Capacity Factor = 0.55 29 4 Capital Cost...are costs that recur throughout the system’s life and includes such items as maintenance, operations, and fuel costs. The capital costs can easily be...form of power plant. Or, second, the present power plant has useful life remaining, but it is desirable to reduce the cost of or dependence on fossil

  16. An Alternative Evacuation Framework to Improve Protective-action Strategies Following a Nuclear Power Accident: The Adaptive Protective Action Zone

    NASA Astrophysics Data System (ADS)

    Hammond, Gregory D.

    Within the U.S. current protective-action strategies to safeguard the public following a nuclear power accident have remained largely unchanged since their implementation in the early 1980s. In the past thirty years, new technologies have been introduced allowing faster computations, better modeling of predicted radiological consequences, and improved accident mapping with geographic information systems (GIS). Utilizing these new technologies, we evaluate the efficacy of alternative strategies, called adaptive protective action zones (APAZs), that use site-specific and event-specific data to dynamically determine evacuation boundaries with simple heuristics in order to better inform protective action decisions (rather than relying on pre-event regulatory bright lines). Several candidate APAZs were developed and then compared to the Nuclear Regulatory Commission's keyhole evacuation strategy (and full evacuation of the emergency planning zone). Two of the APAZs were better on average than existing NRC strategies at reducing either the radiological exposure, the population evacuated, or both. These APAZs are especially effective for larger radioactive plumes and at high population sites; one of them is better at reducing radiation exposure, while the other is better at reducing the population evacuated. However, should policy makers decide that the benefits of APAZs outweigh the costs of implementation, APAZ adoption by U.S. regulatory agencies should be accompanied by a revision to the nuclear-power plant emergency planning basis, and revisions to local nuclear power emergency response planning areas.

  17. Reactive Power and Voltage Optimization Control Strategy in Active Distribution Network Based on the Determination of the Key Nodes

    NASA Astrophysics Data System (ADS)

    Meng, Qingmeng; Che, Renfei; Gao, Shi

    2017-05-01

    The distributed generation which is integrated in the active distribution network changes power flow, bringing new challenges to the voltage control. When voltage limit violation happens, in order to make the voltage return to normal range and improve the voltage quality, a novel voltage control strategy is proposed. Considering the voltage quality and node importance, the electrical closeness centrality and key node contribution degree are defined, and the key nodes are determined by the orders of the key node contribution degree. This paper uses the reactive power compensation devices which are installed at the key nodes coordinated with the reactive power output of the distributed generation to realize the voltage optimization control. The voltage optimization control model is established by taking the minimum power loss as an objective function. Using the particle swarm optimization algorithm solves the model. The simulation results of the improved IEEE-33 bus system verify the effectiveness of the proposed method.

  18. Methane mole fraction and δ13C above and below the trade wind inversion at Ascension Island in air sampled by aerial robotics

    NASA Astrophysics Data System (ADS)

    Brownlow, R.; Lowry, D.; Thomas, R. M.; Fisher, R. E.; France, J. L.; Cain, M.; Richardson, T. S.; Greatwood, C.; Freer, J.; Pyle, J. A.; MacKenzie, A. R.; Nisbet, E. G.

    2016-11-01

    Ascension Island is a remote South Atlantic equatorial site, ideal for monitoring tropical background CH4. In September 2014 and July 2015, octocopters were used to collect air samples in Tedlar bags from different heights above and below the well-defined Trade Wind Inversion (TWI), sampling a maximum altitude of 2700 m above mean sea level. Sampling captured both remote air in the marine boundary layer below the TWI and also air masses above the TWI that had been lofted by convective systems in the African tropics. Air above the TWI was characterized by higher CH4, but no distinct shift in δ13C was observed compared to the air below. Back trajectories indicate that lofted CH4 emissions from Southern Hemisphere Africa have bulk δ13CCH4 signatures similar to background, suggesting mixed emissions from wetlands, agriculture, and biomass burning. The campaigns illustrate the usefulness of unmanned aerial system sampling and Ascension's value for atmospheric measurement in an understudied region.

  19. Research on the Control Strategy for Grid-side Converter of PWM Doubly Fed Induction Wind Power Generators

    NASA Astrophysics Data System (ADS)

    Liu, Yifang; Wang, Zhijie; Li, Renfu; Jiang, Xiuchen; Sheng, Gehao; Liu, Tianyu; Liu, Sanming

    2017-05-01

    When the grid voltage drop, over current of transient rotor and over voltage may damage the power electronic devices. The attenuation of electromagnetic torque will lead to speed up. This paper proposes an improved feed-forward control strategy and its application in the PWM converter. When the PWM converter on voltage drops, bus voltage will be more stable. So over current problems of the DFIG rotor side can be reduced, and it also can improve voltage regulation speed of the DC bus voltage and reduce the oscillation amplitude. Furthermore, the stability of doubly fed wind generator system can be improved. The simulation results verify the validity of the modified control strategy.

  20. [Analysis of the Design of the Ascension® PyroCarbon PIP Total Joint Proximal Component in Relation to the Proximal Phalanx Morphology].

    PubMed

    Hohendorff, B; Zhang, W; Müller, L P; Ries, C

    2015-10-01

    There are many indications that long-term stability of the Ascension(®) pyrocarbon proximal interphalangeal (PIP) total joint is not attained by osseointegration but by appositional bone formation. Accordingly, good locking by cortical bone for sufficient primary stability is necessary in order to avoid prosthesis loosening before enough new bone has been formed. The size of the proximal component of the Ascension(®) PyroCarbon PIP total joint and thus cortical anchorage and primary stability depend on the morphology of the proximal finger phalanx and, especially, on the isthmus of the distal medullary canal. To clarify whether the medullary canal of the proximal finger phalanx can be enlarged using the Ascension(®) pyrocarbon PIP total joint instruments so that cortical contact of the proximal prosthesis component is guaranteed in the region of the isthmus in both sagittal and frontal planes. Before insertion of the Ascension(®) pyrocarbon PIP total joint prosthesis, the isthmus widths of the proximal phalanx of 138 cadaver fingers were measured on radiographs by fluoroscopy in both the frontal and sagittal plane. The measured dimensions were compared to the dimensions of the inserted proximal component stems (manufacturer's instructions) after preparation of the medullary canal. The largest prosthesis possible was always used. The mean isthmus width of the index fingers on PA view was 3.4 mm (2.4-4.2), of the middle fingers 3.3 mm (1.8-4.6), of the ring fingers 3.2 mm (2.2-4.7), and of the small fingers 2.9 mm (1.4-4.3). The mean isthmus width of the index fingers on lateral view was 2.6 mm (1.6-3.7), of the middle fingers 2.5 mm (1.8-3.8), of the ring fingers 2.3 mm (1.5-3.6), and of the small fingers 2.0 mm (1.4-2.8). There were statistically significant differences between the isthmus widths measured before insertion and the stem dimensions of the inserted proximal components. While the average width of the isthmus in the index, middle

  1. Light Water Reactor Sustainability Program Power Uprate Research and Development Strategy

    SciTech Connect

    Hongbin Zhang

    2011-09-01

    The economic incentives for low-cost electricity generation will continue to drive more plant owners to identify safe and reliable methods to increase the electrical power output of the current nuclear power plant fleet. A power uprate enables a nuclear power plant to increase its electrical output with low cost. However, power uprates brought new challenges to plant owners and operators. These include equipment damage or degraded performance, and unanticipated responses to plant conditions, etc. These problems have arisen mainly from using dated design and safety analysis tools and insufficient understanding of the full implications of the proposed power uprate or from insufficient attention to detail during the design and implementation phase. It is essential to demonstrate that all required safety margins have been properly retained and the existing safety level has been maintained or even increased, with consideration of all the conditions and parameters that have an influence on plant safety. The impact of the power uprate on plant life management for long term operation is also an important issue. Significant capital investments are required to extend the lifetime of an aging nuclear power plant. Power uprates can help the plant owner to recover the investment costs. However, plant aging issues may be aggravated by the power uprate due to plant conditions. More rigorous analyses, inspections and monitoring systems are required.

  2. The global rise in methane 2007-present: isotopic constraints from Ascension and Alert. Is a significant change occurring?

    NASA Astrophysics Data System (ADS)

    Nisbet, Euan G.; Manning, Martin R.; Lowry, David; Fisher, Rebecca E.; France, James; Brownlow, Rebecca

    2016-04-01

    Since 2007, atmospheric methane has risen globally by about 6 ppb a year (NOAA data), though with strong year to year variations, after a prolonged approach to equilibrium in the 1980s and 1990s. Much of this growth has been driven from the tropics, especially in the Southern Hemisphere, though with brief episodes of strong growth also in the Arctic in 2007, and in the Northern Hemisphere's low temperate latitudes. Global growth was about 13±1 ppb in 2014 and continued strongly through 2015 (NOAA data). The renewed growth in total methane burden has been accompanied by a significant shift in δ13CCH4 ratio to more 13C depleted values, which began simultaneously with the start of the rise, and has been broadly sustained, although there have also been large short term positive anomalies in δ13CCH4 occurring in both hemispheres. On Ascension island (8oS), δ13CCH4 values through into 2015 have stabilised around 0.2‰ more negative than in 2007-8. Measurements from Cape Point (34oS), and Alert (82oN) show similar patterns, as do NOAA-INSTAAR results from S. Pole. This isotopic trend is quite different from the trend of the 20th century, and implies current growth is driven by biogenic sources, not direct anthropogenic emissions. A budget analysis of both methane mole fraction and δ13CCH4 ratio has been used to investigate patterns. It is unlikely that the growth was driven by reductions in the OH sink, as such scenarios are hard to reconcile with the isotopic record. Increased anthropogenic emissions, from coal and gas leaks or fires, would tend to shift isotopic values to less 13C depleted values, the opposite of observations. The most likely explanation for the change is thus sustained growth in low latitude and southern biogenic sources, probably mainly from tropical wetlands, forests and savannas, with a possible contribution also from ruminants. In total, over the 9 year 2007- 2015 period, methane growth has been about 50-60 ppb, and continuing. The broad

  3. Condom Use Negotiation in Heterosexual African-American Adults: Responses to Types of Social Power-Based Strategies

    PubMed Central

    Otto-Salaj, Laura L.; Reed, Barbara; Brondino, Michael J.; Gore-Felton, Cheryl; Kelly, Jeffrey A.; Stevenson, L. Yvonne

    2009-01-01

    Little research has been performed on how people respond to different strategies to negotiate condom use in sexual situations, and whether certain strategies tend to be perceived as more or less effective in condom use negotiation. This study examined gender differences and preferences in the use of and response to six different styles of condom use negotiation with a hypothetical sexual partner of the opposite gender. Participants were 51 heterosexually-active African-American men and women between the ages of 18 and 35, attending an inner-city community center. Study participants completed a semi-structured qualitative interview in which they were presented with six negotiation strategies —coercive, reward, legitimate, expert, referent, and informational--based on Raven’s 1992 Power/Interaction Model of Interpersonal Influence. Results showed that women participants responded best to referent, reward, and legitimate strategies, and worst to informational tactics. Men participants responded best to reward strategies, and worst to coercion to use condoms. Further, responses given by a subset of both women—and, to a greater extent, men--indicated that use of negotiation tactics involving coercion to use condoms may result in negative or angry reactions. Finally, response to strategies may vary with the value of the relationship as viewed by the target of negotiation. Implications for HIV prevention programs and media campaigns are discussed. PMID:18569536

  4. General volume sizing strategy for thermal storage system using phase change material for concentrated solar thermal power plant

    DOE PAGES

    Xu, Ben; Li, Peiwen; Chan, Cholik; ...

    2014-12-18

    With an auxiliary large capacity thermal storage using phase change material (PCM), Concentrated Solar Power (CSP) is a promising technology for high efficiency solar energy utilization. In a thermal storage system, a dual-media thermal storage tank is typically adopted in industry for the purpose of reducing the use of the heat transfer fluid (HTF) which is usually expensive. While the sensible heat storage system (SHSS) has been well studied, a dual-media latent heat storage system (LHSS) still needs more attention and study. The volume sizing of the thermal storage tank, considering daily cyclic operations, is of particular significance. In thismore » paper, a general volume sizing strategy for LHSS is proposed, based on an enthalpy-based 1D transient model. One example was presented to demonstrate how to apply this strategy to obtain an actual storage tank volume. With this volume, a LHSS can supply heat to a thermal power plant with the HTF at temperatures above a cutoff point during a desired 6 hours of operation. This general volume sizing strategy is believed to be of particular interest for the solar thermal power industry.« less

  5. General volume sizing strategy for thermal storage system using phase change material for concentrated solar thermal power plant

    SciTech Connect

    Xu, Ben; Li, Peiwen; Chan, Cholik; Tumilowicz, Eric

    2014-12-18

    With an auxiliary large capacity thermal storage using phase change material (PCM), Concentrated Solar Power (CSP) is a promising technology for high efficiency solar energy utilization. In a thermal storage system, a dual-media thermal storage tank is typically adopted in industry for the purpose of reducing the use of the heat transfer fluid (HTF) which is usually expensive. While the sensible heat storage system (SHSS) has been well studied, a dual-media latent heat storage system (LHSS) still needs more attention and study. The volume sizing of the thermal storage tank, considering daily cyclic operations, is of particular significance. In this paper, a general volume sizing strategy for LHSS is proposed, based on an enthalpy-based 1D transient model. One example was presented to demonstrate how to apply this strategy to obtain an actual storage tank volume. With this volume, a LHSS can supply heat to a thermal power plant with the HTF at temperatures above a cutoff point during a desired 6 hours of operation. This general volume sizing strategy is believed to be of particular interest for the solar thermal power industry.

  6. Impact of power allocation strategies in long-haul few-mode fiber transmission systems.

    PubMed

    Rafique, Danish; Sygletos, Stylianos; Ellis, Andrew D

    2013-05-06

    We report for the first time on the limitations in the operational power range of few-mode fiber based transmission systems, employing 28 Gbaud quadrature phase shift keying transponders, over 1,600 km. It is demonstrated that if an additional mode is used on a preexisting few-mode transmission link, and allowed to optimize its performance, it will have a significant impact on the pre-existing mode. In particular, we show that for low mode coupling strengths (weak coupling regime), the newly added variable power mode does not considerably impact the fixed power existing mode, with performance penalties less than 2dB (in Q-factor). On the other hand, as mode coupling strength is increased (strong coupling regime), the individual launch power optimization significantly degrades the system performance, with penalties up to ~6 dB. Our results further suggest that mutual power optimization, of both fixed power and variable power modes, reduces power allocation related penalties to less than 3 dB, for any given coupling strength, for both high and low differential mode delays.

  7. A decision tree-based on-line preventive control strategy for power system transient instability prevention

    NASA Astrophysics Data System (ADS)

    Xu, Yan; Dong, Zhao Yang; Zhang, Rui; Wong, Kit Po

    2014-02-01

    Maintaining transient stability is a basic requirement for secure power system operations. Preventive control deals with modifying the system operating point to withstand probable contingencies. In this article, a decision tree (DT)-based on-line preventive control strategy is proposed for transient instability prevention of power systems. Given a stability database, a distance-based feature estimation algorithm is first applied to identify the critical generators, which are then used as features to develop a DT. By interpreting the splitting rules of DT, preventive control is realised by formulating the rules in a standard optimal power flow model and solving it. The proposed method is transparent in control mechanism, on-line computation compatible and convenient to deal with multi-contingency. The effectiveness and efficiency of the method has been verified on New England 10-machine 39-bus test system.

  8. Toward the last frontier - A strategy for the evolutionary development of space nuclear power systems

    NASA Technical Reports Server (NTRS)

    Bennett, Gary L.

    1992-01-01

    A number of exciting mission opportunities are being considered for the 21st century, including advanced robotic science missions to the outer planets and beyond, human exploration of the Moon and Mars, and advanced space transportation systems. All of these missions will require some form of nuclear power; however, it is clear that current budgetary constraints preclude developing many different types of space nuclear power systems. This paper reviews the specific civil space missions which have been identified, the power levels and lifetimes required, and the technologies available. From this an evolutionary space nuclear power program is developed which builds upon the experience of radioisotope thermoelectric generators, dynamic isotope power systems, and space nuclear reactors. It is strongly suggested that not only does this approach make technical and budgetary sense but that it is consistent with the normal development of new technologies.

  9. Conceptual Design and Optimal Power Control Strategy for AN Eco-Friendly Hybrid Vehicle

    NASA Astrophysics Data System (ADS)

    Nasiri, N. Mir; Chieng, Frederick T. A.

    2011-06-01

    This paper presents a new concept for a hybrid vehicle using a torque and speed splitting technique. It is implemented by the newly developed controller in combination with a two degree of freedom epicyclic gear transmission. This approach enables optimization of the power split between the less powerful electrical motor and more powerful engine while driving a car load. The power split is fundamentally a dual-energy integration mechanism as it is implemented by using the epicyclic gear transmission that has two inputs and one output for a proper power distribution. The developed power split control system manages the operation of both the inputs to have a known output with the condition of maintaining optimum operating efficiency of the internal combustion engine and electrical motor. This system has a huge potential as it is possible to integrate all the features of hybrid vehicle known to-date such as the regenerative braking system, series hybrid, parallel hybrid, series/parallel hybrid, and even complex hybrid (bidirectional). By using the new power split system it is possible to further reduce fuel consumption and increase overall efficiency.

  10. General analysis of SRS-limited high-power fiber lasers and design strategy.

    PubMed

    Liu, Wei; Ma, Pengfei; Lv, Haibin; Xu, Jiangmin; Zhou, Pu; Jiang, Zongfu

    2016-11-14

    In this paper, a spectral model by incorporating SRS effect is proposed and established, which is feasible for analyzing the SRS effect both in high-power fiber oscillator and master oscillator power amplifier (MOPA) system. The theoretical results show that the SRS effect is tightly related to the bandwidths of the fiber Bragg gratings (FBGs) and it can be efficiently suppressed by optimizing the bandwidth of the FBGs. Besides, the established theoretical model is also feasible for analyzing the influence of seed power on the SRS effect. The theoretical predictions agree well with the previous experimental results.

  11. Advanced regulatory control and coordinated plant-wide control strategies for IGCC targeted towards improving power ramp-rates

    SciTech Connect

    Mahapatra, P.; Zitney, S.

    2012-01-01

    As part of ongoing R&D activities at the National Energy Technology Laboratory's (NETL) Advanced Virtual Energy Simulation Training & Research (AVESTAR™) Center, this paper highlights strategies for enhancing low-level regulatory control and system-wide coordinated control strategies implemented in a high-fidelity dynamic simulator for an Integrated Gasification Combined Cycle (IGCC) power plant with carbon capture. The underlying IGCC plant dynamic model contains 20 major process areas, each of which is tightly integrated with the rest of the power plant, making individual functionally-independent processes prone to routine disturbances. Single-loop feedback control although adequate to meet the primary control objective for most processes, does not take into account in advance the effect of these disturbances, making the entire power plant undergo large offshoots and/or oscillations before the feedback action has an opportunity to impact control performance. In this paper, controller enhancements ranging from retuning feedback control loops, multiplicative feed-forward control and other control techniques such as split-range control, feedback trim and dynamic compensation, applicable on various subsections of the integrated IGCC plant, have been highlighted and improvements in control responses have been given. Compared to using classical feedback-based control structure, the enhanced IGCC regulatory control architecture reduces plant settling time and peak offshoots, achieves faster disturbance rejection, and promotes higher power ramp-rates. In addition, improvements in IGCC coordinated plant-wide control strategies for “Gasifier-Lead”, “GT-Lead” and “Plantwide” operation modes have been proposed and their responses compared. The paper is concluded with a brief discussion on the potential IGCC controller improvements resulting from using advanced process control, including model predictive control (MPC), as a supervisory control layer.

  12. Optimization Strategies for the Vulnerability Analysis of the Electric Power Grid

    SciTech Connect

    Pinar, A.; Meza, J.; Donde, V.; Lesieutre, B.

    2007-11-13

    Identifying small groups of lines, whose removal would cause a severe blackout, is critical for the secure operation of the electric power grid. We show how power grid vulnerability analysis can be studied as a mixed integer nonlinear programming (MINLP) problem. Our analysis reveals a special structure in the formulation that can be exploited to avoid nonlinearity and approximate the original problem as a pure combinatorial problem. The key new observation behind our analysis is the correspondence between the Jacobian matrix (a representation of the feasibility boundary of the equations that describe the flow of power in the network) and the Laplacian matrix in spectral graph theory (a representation of the graph of the power grid). The reduced combinatorial problem is known as the network inhibition problem, for which we present a mixed integer linear programming formulation. Our experiments on benchmark power grids show that the reduced combinatorial model provides an accurate approximation, to enable vulnerability analyses of real-sized problems with more than 10,000 power lines.

  13. Optimization strategies for the vulnerability analysis of the electric power grid.

    SciTech Connect

    Meza, Juan C.; Pinar, Ali; Lesieutre, Bernard; Donde, Vaibhav

    2009-03-01

    Identifying small groups of lines, whose removal would cause a severe blackout, is critical for the secure operation of the electric power grid. We show how power grid vulnerability analysis can be studied as a mixed integer nonlinear programming (minlp) problem. Our analysis reveals a special structure in the formulation that can be exploited to avoid nonlinearity and approximate the original problem as a pure combinatorial problem. The key new observation behind our analysis is the correspondence between the Jacobian matrix (a representation of the feasibility boundary of the equations that describe the flow of power in the network) and the Laplacian matrix in spectral graph theory (a representation of the graph of the power grid). The reduced combinatorial problem is known as the network inhibition problem, for which we present a mixed integer linear programming formulation. Our experiments on benchmark power grids show that the reduced combinatorial model provides an accurate approximation, to enable vulnerability analyses of real-sized problems with more than 10,000 power lines.

  14. Research on Operation Strategy for Bundled Wind-thermal Generation Power Systems Based on Two-Stage Optimization Model

    NASA Astrophysics Data System (ADS)

    Sun, Congcong; Wang, Zhijie; Liu, Sanming; Jiang, Xiuchen; Sheng, Gehao; Liu, Tianyu

    2017-05-01

    Wind power has the advantages of being clean and non-polluting and the development of bundled wind-thermal generation power systems (BWTGSs) is one of the important means to improve wind power accommodation rate and implement “clean alternative” on generation side. A two-stage optimization strategy for BWTGSs considering wind speed forecasting results and load characteristics is proposed. By taking short-term wind speed forecasting results of generation side and load characteristics of demand side into account, a two-stage optimization model for BWTGSs is formulated. By using the environmental benefit index of BWTGSs as the objective function, supply-demand balance and generator operation as the constraints, the first-stage optimization model is developed with the chance-constrained programming theory. By using the operation cost for BWTGSs as the objective function, the second-stage optimization model is developed with the greedy algorithm. The improved PSO algorithm is employed to solve the model and numerical test verifies the effectiveness of the proposed strategy.

  15. Flexible operation strategy for environment control system in abnormal supply power condition

    NASA Astrophysics Data System (ADS)

    Liping, Pang; Guoxiang, Li; Hongquan, Qu; Yufeng, Fang

    2017-04-01

    This paper establishes an optimization method that can be applied to the flexible operation of the environment control system in an abnormal supply power condition. A proposed conception of lifespan is used to evaluate the depletion time of the non-regenerative substance. The optimization objective function is to maximize the lifespans. The optimization variables are the allocated powers of subsystems. The improved Non-dominated Sorting Genetic Algorithm is adopted to obtain the pareto optimization frontier with the constraints of the cabin environmental parameters and the adjustable operating parameters of the subsystems. Based on the same importance of objective functions, the preferred power allocation of subsystems can be optimized. Then the corresponding running parameters of subsystems can be determined to ensure the maximum lifespans. A long-duration space station with three astronauts is used to show the implementation of the proposed optimization method. Three different CO2 partial pressure levels are taken into consideration in this study. The optimization results show that the proposed optimization method can obtain the preferred power allocation for the subsystems when the supply power is at a less-than-nominal value. The method can be applied to the autonomous control for the emergency response of the environment control system.

  16. Systems and methods for providing power to a load based upon a control strategy

    DOEpatents

    Perisic, Milun; Kajouke, Lateef A; Ransom, Ray M

    2013-12-24

    Systems and methods are provided for an electrical system. The electrical system includes a load, an interface configured to receive a voltage from a voltage source, and a controller configured to receive the voltage from the voltage source through the interface and to provide a voltage and current to the load. Wherein, when the controller is in a constant voltage mode, the controller provides a constant voltage to the load, when the controller is in a constant current mode, the controller provides a constant current to the load, and when the controller is in a constant power mode, the controller provides a constant power to the load.

  17. An Efficient Energy Management Strategy, Unique Power Split & Energy Distribution, Based on Calculated Vehicle Road Loads

    DTIC Science & Technology

    2012-08-01

    characteristic and efficiency maps. Rigorous dynamometer testing has been performed to characterize main hybrid components. The data gathered from the... dynamometer testing was used to further fine tune and improve vehicle simulation and control software. Samples of the types of characterization data...characteristics are confirmed during the dynamometer testing phases and fed back into the base simulation to adjust control parameters and strategy

  18. The Power of ROFO Principle Together with Companywide Training in Executing Lean Production Strategy

    ERIC Educational Resources Information Center

    Goh, Ah Bee; Chakpitak, Nopasit; Sureephong, Pradorn

    2015-01-01

    This paper reports the findings of the case study conducted at Schaffner Thailand (ST) factory regarding the application of the ROFO principle coupled with companywide training on the execution of Lean Production (LP) strategy. The case study was motivated by 3 main objectives: 1) to examine the effectiveness of the ROFO principle and companywide…

  19. Becoming a Great Teacher of Reading: Achieving High Rapid Reading Gains with Powerful, Differentiated Strategies

    ERIC Educational Resources Information Center

    Carbo, Marie

    2007-01-01

    Literacy expert Marie Carbo pairs identifying each learner's unique reading style with a wide range of differentiated strategies to help all learners experience greater reading success. Using these research-based methods, both novice and experienced teachers can increase reading achievement with all learners, including those who are at-risk,…

  20. Synergistic mercury removal by conventional pollutant control strategies for coal-fired power plants in China.

    PubMed

    Wang, Shuxiao; Zhang, Lei; Wu, Ye; Ancora, Maria Pia; Zhao, Yu; Hao, Jiming

    2010-06-01

    China's 11th 5-yr plan has regulated total sulfur dioxide (SO2) emissions by installing flue gas desulfurization (FGD) devices and shutting down small thermal power units. These control measures will not only significantly reduce the emission of conventional pollutants but also benefit the reduction of mercury emissions from coal-fired power plants. This paper uses the emission factor method to estimate the efficiencies of these measures on mercury emission abatement. From 2005 to 2010, coal consumption in power plants will increase by 59%; however, the mercury emission will only rise from 141 to 155 t, with an increase of 10%. The average emission rate of mercury from coal burning will decrease from 126 mg Hg/t of coal to 87 mg Hg/t of coal. The effects of the three desulfurization measures were assessed and show that wet FGD will play an important role in mercury removal. Mercury emissions in 2015 and 2020 are also projected under different policy scenarios. Under the most probable scenario, the total mercury emission in coal-fired power plants in China will decrease to 130 t by 2020, which will benefit from the rapid installation of fabric filters and selective catalytic reduction.

  1. The Power of Teacher Teams: With Cases, Analyses, and Strategies for Success

    ERIC Educational Resources Information Center

    Troen, Vivian; Boles, Katherine C.

    2012-01-01

    While most educators believe working in teams is valuable, not all team efforts lead to instructional improvement. Through richly detailed case studies, "The Power of Teacher Teams" demonstrates how schools can transform their teams into more effective learning communities that foster teacher leadership. The benefits of successful teacher teams…

  2. The Power of Teacher Teams: With Cases, Analyses, and Strategies for Success

    ERIC Educational Resources Information Center

    Troen, Vivian; Boles, Katherine C.

    2012-01-01

    While most educators believe working in teams is valuable, not all team efforts lead to instructional improvement. Through richly detailed case studies, "The Power of Teacher Teams" demonstrates how schools can transform their teams into more effective learning communities that foster teacher leadership. The benefits of successful teacher teams…

  3. Physician-friendly strategies boost the power and reach of DM.

    PubMed

    2004-07-01

    Why? Because physicians have a powerful influence over patient behavior, and you can accomplish much more with their active and enthusiastic support. Further, while physicians may be skeptical or even antagonistic toward DM interventions at first, you can take steps to win their confidence and cooperation.

  4. Maintenance error reduction strategies in nuclear power plants, using root cause analysis.

    PubMed

    Wu, T M; Hwang, S L

    1989-06-01

    This study proposes a conceptual model of maintenance tasks to facilitate the identification of root causes of human errors in carrying out such tasks in nuclear power plants. Based on this model, an external/internal classification scheme was developed to discover the root causes of human errors. As a consequence, certain policies pertaining to human error prevention or correction were proposed.

  5. Strategy to control type I error increases power to identify genetic variation using the full biological trajectory.

    PubMed

    Benke, K S; Wu, Y; Fallin, D M; Maher, B; Palmer, L J

    2013-07-01

    Genome-wide association studies have been successful in identifying loci that underlie continuous traits measured at a single time point. To additionally consider continuous traits longitudinally, it is desirable to look at SNP effects at baseline and over time using linear-mixed effects models. Estimation and interpretation of two coefficients in the same model raises concern regarding the optimal control of type I error. To investigate this issue, we calculate type I error and power under an alternative for joint tests, including the two degree of freedom likelihood ratio test, and compare this to single degree of freedom tests for each effect separately at varying alpha levels. We show which joint tests are the optimal way to control the type I error and also illustrate that information can be gained by joint testing in situations where either or both SNP effects are underpowered. We also show that closed form power calculations can approximate simulated power for the case of balanced data, provide reasonable approximations for imbalanced data, but overestimate power for complicated residual error structures. We conclude that a two degree of freedom test is an attractive strategy in a hypothesis-free genome-wide setting and recommend its use for genome-wide studies employing linear-mixed effects models.

  6. Strategy to Control Type I Error Increases Power to Identify Genetic Variation Using the Full Biological Trajectory

    PubMed Central

    Benke, K. S.; Wu, Y.; Fallin, D. M.; Maher, B.; Palmer, L. J.

    2013-01-01

    Genome-wide association studies have been successful in identifying loci that underlie continuous traits measured at a single time point. To additionally consider continuous traits longitudinally, it is desirable to look at SNP effects at baseline and over time using linear-mixed effects models. Estimation and interpretation of two coefficients in the same model raises concern regarding the optimal control of type I error. To investigate this issue, we calculate type I error and power under an alternative for joint tests, including the two degree of freedom likelihood ratio test, and compare this to single degree of freedom tests for each effect separately at varying alpha levels. We show which joint tests are the optimal way to control the type I error and also illustrate that information can be gained by joint testing in situations where either or both SNP effects are underpowered. We also show that closed form power calculations can approximate simulated power for the case of balanced data, provide reasonable approximations for imbalanced data, but overestimate power for complicated residual error structures. We conclude that a two degree of freedom test is an attractive strategy in a hypothesis-free genome-wide setting and recommend its use for genome-wide studies employing linear-mixed effects models. PMID:23633177

  7. Training Strategies to Improve Muscle Power: Is Olympic-style Weightlifting Relevant?

    PubMed

    Helland, Christian; Hole, Eirik; Iversen, Erik; Olsson, Monica Charlotte; Seynnes, Olivier; Solberg, Paul Andre; Paulsen, Gøran

    2017-04-01

    This efficacy study investigated the effects of 1) Olympic-style weightlifting (OWL), 2) motorized strength and power training (MSPT), and 3) free weight strength and power training (FSPT) on muscle power. Thirty-nine young athletes (20 ± 3 yr; ice hockey, volleyball, and badminton) were randomized into the three training groups. All groups participated in two to three sessions per week for 8 wk. The MSPT and FSPT groups trained using squats (two legs and single leg) with high force and high power, whereas the OWL group trained using clean and snatch exercises. MSPT was conducted as slow-speed isokinetic strength training and isotonic power training with augmented eccentric load, controlled by a computerized robotic engine system. FSPT used free weights. The training volume (sum of repetitions × kg) was similar between all three groups. Vertical jumping capabilities were assessed by countermovement jump (CMJ), squat jump (SJ), drop jump (DJ), and loaded CMJ (10-80 kg). Sprinting capacity was assessed in a 30-m sprint. Secondary variables were squat one-repetition maximum (1RM), body composition, quadriceps thickness, and architecture. OWL resulted in trivial improvements and inferior gains compared with FSPT and MSPT for CMJ, SJ, DJ, and 1RM. MSPT demonstrated small but robust effects on SJ, DJ, loaded CMJ, and 1RM (3%-13%). MSPT was superior to FSPT in improving 30-m sprint performance. FSPT and MSPT, but not OWL, demonstrated increased thickness in the vastus lateralis and rectus femoris (4%-7%). MSPT was time-efficient and equally or more effective than FSPT training in improving vertical jumping and sprinting performance. OWL was generally ineffective and inferior to the two other interventions.

  8. Gains in power for exhaustive analyses of haplotypes using variable-sized sliding window strategy: a comparison of association-mapping strategies.

    PubMed

    Guo, Yanfang; Li, Jian; Bonham, Aaron J; Wang, Yuping; Deng, Hongwen

    2009-06-01

    Linkage disequilibrium (LD)-based association mapping is often performed by analyzing either individual SNPs or block-based multi-SNP haplotypes. Sliding windows of several fixed sizes (in terms of SNP numbers) were also applied to a few simulated or real data sets. In comparison, exhaustively testing based on variable-sized sliding windows (VSW) of all possible sizes of SNPs over a genomic region has the best chance to capture the optimum markers (single SNPs or haplotypes) that are most significantly associated with the traits under study. However, the cost is the increased number of multiple tests and computation. Here, a strategy of VSW of all possible sizes is proposed and its power is examined, in comparison with those using only haplotype blocks (BLK) or single SNP loci (SGL) tests. Critical values for statistical significance testing that account for multiple testing are simulated. We demonstrated that, over a wide range of parameters simulated, VSW increased power for the detection of disease variants by approximately 1-15% over the BLK and SGL approaches. The improved performance was more significant in regions with high recombination rates. In an empirical data set, VSW obtained the most significant signal and identified the LRP5 gene as strongly associated with osteoporosis. With the use of computational techniques such as parallel algorithms and clustering computing, it is feasible to apply VSW to large genomic regions or those regions preliminarily identified by traditional SGL/BLK methods.

  9. Economic Warfare: A Study of US and China Strategy Using the Economic Element of National Power

    DTIC Science & Technology

    2007-05-10

    Greenburg “China’s Free Trade Relationship with the United States: Economic Boon or “Unrestricted Warfare”” USAWC Strategy Research Project, Carlisle...China’s entry into the WTO, do not tell the complete story. The codependency between the U.S. and China is not sustainable. The U.S. cannot...gold/gold_china.html, 2005. Greenburg, Cdr James R. China’s Free Trade Relationship with the United States: Economic Boon or “Unrestricted

  10. An effective control strategy to maximize power extraction from wind turbines

    NASA Astrophysics Data System (ADS)

    Mouhadjer, Samir; Benmedjahed, Miloud; Neçaïbia, Ammar

    2016-07-01

    Among the various identifiable renewable energies sources, one holds the attention in this study for its important potential in the world; it's about wind energy. Our objective in this present work is to contribute a share to the research solution to the problems of coupling between this energy source and the load; it's about the transfer of the maximum power to the latter which often suffers from a bad matching. In order to maximize the wind power extraction, this work describes design of a PWM rectifier controller for wind turbines. Generic PWM rectifier is used and PICl6F876 Microcontroller is proposed. The goal of the controller is to keep operating point as close to the maximum efficiency as possible.

  11. Fault Characteristics of Full Power Inverted Source Considering Low-voltage Ride Through Control Strategy

    NASA Astrophysics Data System (ADS)

    Zhang, Chi; Zeng, Jie; Zhao, Wei; Zhong, Guobin; Xu, Qi; Luo, Pandian; Li, Weiren; Liu, Bohan

    2017-05-01

    New energy source is thriving in China. However, the fault characteristics of grids have been altered significantly with the penetration of new energy source increasing. In conventional researches, the fault features of wind farms were discussed briefly or simply overlooked. This paper began with the theoretical analysis of control system of full power inverted (FPI) sources and indicated that the response time of current control loop is 8.5 ms, while the steady state current of FPI source is controlled by reference values and set value of current limiter; the expressions of steady state current of FPI source were presented then. In addition, main factors affecting fault current, including different active power generation before fault, different fault locations and different fault types, were analyzed comprehensively and compared through simulation to gain a clear insight into the whole process of faults. The research is helpful to obtain a better understanding of new energy source.

  12. Settler colonial power and the American Indian sovereignty movement: forms of domination, strategies of transformation.

    PubMed

    Steinman, Erich

    2012-01-01

    The article extends the multi-institutional model of power and change through an analysis of the American Indian Sovereignty Movement. Drawing upon cultural models of the state, and articulating institutionalist conceptions of political opportunities and resources, the analysis demonstrates that this framework can be applied to challenges addressing the state as well as nonstate fields. The rational-legal diminishment of tribal rights, bureaucratic paternalism, commonsense views of tribes as racial/ethnic minorities, and the binary construction of American and Indian as oppositional identities diminished the appeal of "contentious" political action. Instead, to establish tribes' status as sovereign nations, tribal leaders aggressively enacted infrastructural power, transposed favorable legal rulings across social fields to legitimize sovereignty discourses, and promoted a pragmatic coexistence with state and local governments. Identifying the United States as a settler colonial society, the study suggests that a decolonizing framework is more apt than racial/ethnicity approaches in conceptualizing the struggle of American Indians.

  13. A simple packet retransmission strategy for throughput and delay enhancement on power line communication channels

    SciTech Connect

    Onunga, J.O. ); Donaldson, R.W. . Dept. of Electrical Engineering)

    1993-07-01

    A new, simple, and effective communication protocol is developed and evaluated for use on power line distribution networks. The protocol involves retransmission of unacknowledged packets, which are sent in either single or multiple (N) copies in accordance with estimates of communication link quality. Multiple packet copies can be code combined at the receiver, using majority voting on each bit position, to reduce packet error rates. Adaptive link quality estimates are based on the receipt or absence of positive acknowledgements. Information throughput efficiency is calculated and N optimized in terms of system variables. Performance benefits of code combining are clearly demonstrated. The algorithm was implemented and tested using a five-station intrabuilding power line communications network operating at 1.2, 2.4, 4.8 and 9.6 kbit/s data rate. Substantial throughput and delay improvement occurred on poor quality links, without degrading performance on good links.

  14. Control Strategies for Smoothing of Output Power of Wind Energy Conversion Systems

    NASA Astrophysics Data System (ADS)

    Pratap, Alok; Urasaki, Naomitsu; Senju, Tomonobu

    2013-10-01

    This article presents a control method for output power smoothing of a wind energy conversion system (WECS) with a permanent magnet synchronous generator (PMSG) using the inertia of wind turbine and the pitch control. The WECS used in this article adopts an AC-DC-AC converter system. The generator-side converter controls the torque of the PMSG, while the grid-side inverter controls the DC-link and grid voltages. For the generator-side converter, the torque command is determined by using the fuzzy logic. The inputs of the fuzzy logic are the operating point of the rotational speed of the PMSG and the difference between the wind turbine torque and the generator torque. By means of the proposed method, the generator torque is smoothed, and the kinetic energy stored by the inertia of the wind turbine can be utilized to smooth the output power fluctuations of the PMSG. In addition, the wind turbines shaft stress is mitigated compared to a conventional maximum power point tracking control. Effectiveness of the proposed method is verified by the numerical simulations.

  15. Toward a systematic strategy for defining power counting in the construction of the energy density functional

    NASA Astrophysics Data System (ADS)

    Yang, C.-J.; Grasso, M.; Lacroix, D.

    2017-09-01

    We propose a new scheme for constructing an effective-field-theory-based interaction to be used in the energy-density-functional (EDF) theory with specific assumptions for defining a power counting. This procedure is developed through the evaluation of the equation of state (EOS) of symmetric and pure neutron matter going beyond the mean-field scheme and using a functional defined up to next-to-leading order (NLO), which we call the NLO EDF. A Skyrme-like interaction is constructed based on the condition of renormalizibility and on power counting on kF/Λh i , where kF is the Fermi momentum and Λh i is the breakdown scale of our expansion. To absorb the divergences present in beyond mean-field diagrams, counter interactions are introduced for the NLO EDF and determined through renormalization conditions. In particular, three scenarios are explored and all of them lead to satisfactory results. These counter interactions contain also parameters that do not contribute to the EOS of matter and may eventually be determined through future adjustments to properties of some selected finite nuclei. Our work serves as a simple starting point for constructing a well-defined power counting within the EDF framework.

  16. Control strategies of atmospheric mercury emissions from coal-fired power plants in China.

    PubMed

    Tian, Hezhong; Wang, Yan; Cheng, Ke; Qu, Yiping; Hao, Jiming; Xue, Zhigang; Chai, Fahe

    2012-05-01

    Atmospheric mercury (Hg) emission from coal is one of the primary sources of anthropogenic discharge and pollution. China is one of the few countries in the world whose coal consumption constitutes about 70% of total primary energy, and over half of coals are burned directly for electricity generation. Atmospheric emissions of Hg and its speciation from coal-fired power plants are of great concern owing to their negative impacts on regional human health and ecosystem risks, as well as long-distance transport. In this paper, recent trends of atmospheric Hg emissions and its species split from coal-fired power plants in China during the period of 2000-2007 are evaluated, by integrating each plant's coal consumption and emission factors, which are classified by different subcategories of boilers, particulate matter (PM) and sulfur dioxide (SO2) control devices. Our results show that the total Hg emissions from coal-fired power plants have begun to decrease from the peak value of 139.19 t in 2005 to 134.55 t in 2007, though coal consumption growing steadily from 1213.8 to 1532.4 Mt, which can be mainly attributed to the co-benefit Hg reduction by electrostatic precipitators/fabric filters (ESPs/FFs) and wet flue gas desulfurization (WFGD), especially the sharp growth in installation of WFGD both in the new and existing power plants since 2005. In the coming 12th five-year-plan, more and more plants will be mandated to install De-NO(x) (nitrogen oxides) systems (mainly selective catalytic reduction [SCR] and selective noncatalytic reduction [SNCR]) for minimizing NO(x) emission, thus the specific Hg emission rate per ton of coal will decline further owing to the much higher co-benefit removal efficiency by the combination of SCR + ESPs/FFs + WFGD systems. Consequently, SCR + ESPs/FFs + WFGD configuration will be the main path to abate Hg discharge from coal-fired power plants in China in the near future. However advanced specific Hg removal technologies are necessary

  17. Enhancing Specific Energy and Power in Asymmetric Supercapacitors - A Synergetic Strategy based on the Use of Redox Additive Electrolytes

    NASA Astrophysics Data System (ADS)

    Singh, Arvinder; Chandra, Amreesh

    2016-05-01

    The strategy of using redox additive electrolyte in combination with multiwall carbon nanotubes/metal oxide composites leads to a substantial improvements in the specific energy and power of asymmetric supercapacitors (ASCs). When the pure electrolyte is optimally modified with a redox additive viz., KI, ~105% increase in the specific energy is obtained with good cyclic stability over 3,000 charge-discharge cycles and ~14.7% capacitance fade. This increase is a direct consequence of the iodine/iodide redox pairs that strongly modifies the faradaic and non-faradaic type reactions occurring on the surface of the electrodes. Contrary to what is shown in few earlier reports, it is established that indiscriminate increase in the concentration of redox additives will leads to performance loss. Suitable explanations are given based on theoretical laws. The specific energy or power values being reported in the fabricated ASCs are comparable or higher than those reported in ASCs based on toxic acetonitrile or expensive ionic liquids. The paper shows that the use of redox additive is economically favorable strategy for obtaining cost effective and environmentally friendly ASCs.

  18. Enhancing Specific Energy and Power in Asymmetric Supercapacitors - A Synergetic Strategy based on the Use of Redox Additive Electrolytes

    PubMed Central

    Singh, Arvinder; Chandra, Amreesh

    2016-01-01

    The strategy of using redox additive electrolyte in combination with multiwall carbon nanotubes/metal oxide composites leads to a substantial improvements in the specific energy and power of asymmetric supercapacitors (ASCs). When the pure electrolyte is optimally modified with a redox additive viz., KI, ~105% increase in the specific energy is obtained with good cyclic stability over 3,000 charge-discharge cycles and ~14.7% capacitance fade. This increase is a direct consequence of the iodine/iodide redox pairs that strongly modifies the faradaic and non-faradaic type reactions occurring on the surface of the electrodes. Contrary to what is shown in few earlier reports, it is established that indiscriminate increase in the concentration of redox additives will leads to performance loss. Suitable explanations are given based on theoretical laws. The specific energy or power values being reported in the fabricated ASCs are comparable or higher than those reported in ASCs based on toxic acetonitrile or expensive ionic liquids. The paper shows that the use of redox additive is economically favorable strategy for obtaining cost effective and environmentally friendly ASCs. PMID:27184260

  19. Enhancing Specific Energy and Power in Asymmetric Supercapacitors - A Synergetic Strategy based on the Use of Redox Additive Electrolytes.

    PubMed

    Singh, Arvinder; Chandra, Amreesh

    2016-05-17

    The strategy of using redox additive electrolyte in combination with multiwall carbon nanotubes/metal oxide composites leads to a substantial improvements in the specific energy and power of asymmetric supercapacitors (ASCs). When the pure electrolyte is optimally modified with a redox additive viz., KI, ~105% increase in the specific energy is obtained with good cyclic stability over 3,000 charge-discharge cycles and ~14.7% capacitance fade. This increase is a direct consequence of the iodine/iodide redox pairs that strongly modifies the faradaic and non-faradaic type reactions occurring on the surface of the electrodes. Contrary to what is shown in few earlier reports, it is established that indiscriminate increase in the concentration of redox additives will leads to performance loss. Suitable explanations are given based on theoretical laws. The specific energy or power values being reported in the fabricated ASCs are comparable or higher than those reported in ASCs based on toxic acetonitrile or expensive ionic liquids. The paper shows that the use of redox additive is economically favorable strategy for obtaining cost effective and environmentally friendly ASCs.

  20. Impact of Different Ventilation Strategies on Driving Pressure, Mechanical Power, and Biological Markers During Open Abdominal Surgery in Rats.

    PubMed

    Maia, Lígia de A; Samary, Cynthia S; Oliveira, Milena V; Santos, Cintia L; Huhle, Robert; Capelozzi, Vera L; Morales, Marcelo M; Schultz, Marcus J; Abreu, Marcelo G; Pelosi, Paolo; Silva, Pedro L; Rocco, Patricia Rieken Macedo

    2017-10-01

    Intraoperative mechanical ventilation may yield lung injury. To date, there is no consensus regarding the best ventilator strategy for abdominal surgery. We aimed to investigate the impact of the mechanical ventilation strategies used in 2 recent trials (Intraoperative Protective Ventilation [IMPROVE] trial and Protective Ventilation using High versus Low PEEP [PROVHILO] trial) on driving pressure (ΔPRS), mechanical power, and lung damage in a model of open abdominal surgery. Thirty-five Wistar rats were used, of which 28 were anesthetized, and a laparotomy was performed with standardized bowel manipulation. Postoperatively, animals (n = 7/group) were randomly assigned to 4 hours of ventilation with: (1) tidal volume (VT) = 7 mL/kg and positive end-expiratory pressure (PEEP) = 1 cm H2O without recruitment maneuvers (RMs) (low VT/low PEEP/RM-), mimicking the low-VT/low-PEEP strategy of PROVHILO; (2) VT = 7 mL/kg and PEEP = 3 cm H2O with RMs before laparotomy and hourly thereafter (low VT/moderate PEEP/4 RM+), mimicking the protective ventilation strategy of IMPROVE; (3) VT = 7 mL/kg and PEEP = 6 cm H2O with RMs only before laparotomy (low VT/high PEEP/1 RM+), mimicking the strategy used after intubation and before extubation in PROVHILO; or (4) VT = 14 mL/kg and PEEP = 1 cm H2O without RMs (high VT/low PEEP/RM-), mimicking conventional ventilation used in IMPROVE. Seven rats were not tracheotomized, operated, or mechanically ventilated, and constituted the healthy nonoperated and nonventilated controls. Low VT/moderate PEEP/4 RM+ and low VT/high PEEP/1 RM+, compared to low VT/low PEEP/RM- and high VT/low PEEP/RM-, resulted in lower ΔPRS (7.1 ± 0.8 and 10.2 ± 2.1 cm H2O vs 13.9 ± 0.9 and 16.9 ± 0.8 cm H2O, respectively; P< .001) and less mechanical power (63 ± 7 and 79 ± 20 J/min vs 110 ± 10 and 120 ± 20 J/min, respectively; P = .007). Low VT/high PEEP/1 RM+ was associated with less alveolar collapse than low VT/low PEEP/RM- (P = .03). E-cadherin expression

  1. The effect of crank rate strategy on peak aerobic power and peak physiological responses during arm crank ergometry.

    PubMed

    Smith, Paul M; Doherty, Mike; Price, Michael J

    2007-04-01

    The main aim of this study was to determine whether the use of an imposed or freely chosen crank rate would influence submaximal and peak physiological responses during arm crank ergometry. Fifteen physically active men participated in the study. Their mean age, height, and body mass were 25.9 (s = 6.2) years, 1.80 (s = 0.10) m, and 78.4 (s = 6.1) kg, respectively. The participants performed two incremental peak oxygen consumption (VO(2peak)) tests using an electronically braked ergometer. One test was performed using an imposed crank rate of 80 rev x min(-1), whereas in the other the participants used spontaneously chosen crank rates. The order in which the tests were performed was randomized, and they were separated by at least 2 days. Respiratory data were collected using an on-line gas analysis system, and fingertip capillary blood samples ( approximately 20 microl) were collected for the determination of blood lactate concentration. Heart rate was also recorded throughout the tests. Time to exhaustion was measured and peak aerobic power calculated. Submaximal data were analysed using separate two-way repeated-measures analyses of variance, while differences in peak values were analysed using separate paired t-tests. Variations in spontaneously chosen crank rate were assessed using a one-way analysis of variance with repeated measures. Agreement between the crank rate strategies for the assessment of peak values was examined by calculating intra-class correlation coefficients (ICC) and 95% limits of agreement (95% LoA). While considerable between-participant variations in spontaneously chosen crank rate were observed, the mean value was not different (P > 0.05) from the imposed crank rate of 80 rev x min(-1) at any point. No differences (P > 0.05) were observed for submaximal data between crank strategies. Furthermore, mean peak minute power [158 (s = 20) vs. 158 (s = 18) W], time to exhaustion [739 (s = 118) vs. 727 (s = 111) s], and VO(2peak)[3.09 (s = 0

  2. Predictive control strategy of a gas turbine for improvement of combined cycle power plant dynamic performance and efficiency.

    PubMed

    Mohamed, Omar; Wang, Jihong; Khalil, Ashraf; Limhabrash, Marwan

    2016-01-01

    This paper presents a novel strategy for implementing model predictive control (MPC) to a large gas turbine power plant as a part of our research progress in order to improve plant thermal efficiency and load-frequency control performance. A generalized state space model for a large gas turbine covering the whole steady operational range is designed according to subspace identification method with closed loop data as input to the identification algorithm. Then the model is used in developing a MPC and integrated into the plant existing control strategy. The strategy principle is based on feeding the reference signals of the pilot valve, natural gas valve, and the compressor pressure ratio controller with the optimized decisions given by the MPC instead of direct application of the control signals. If the set points for the compressor controller and turbine valves are sent in a timely manner, there will be more kinetic energy in the plant to release faster responses on the output and the overall system efficiency is improved. Simulation results have illustrated the feasibility of the proposed application that has achieved significant improvement in the frequency variations and load following capability which are also translated to be improvements in the overall combined cycle thermal efficiency of around 1.1 % compared to the existing one.

  3. Designing Effective Persuasive Systems Utilizing the Power of Entanglement: Communication Channel, Strategy and Affect

    NASA Astrophysics Data System (ADS)

    Li, Haiqing; Chatterjee, Samir

    With rapid advances in information and communication technology, computer-mediated communication (CMC) technologies are utilizing multiple IT platforms such as email, websites, cell-phones/PDAs, social networking sites, and gaming environments. However, no studies have compared the effectiveness of a persuasive system using such alternative channels and various persuasive techniques. Moreover, how affective computing impacts the effectiveness of persuasive systems is not clear. This study proposes (1) persuasive technology channels in combination with persuasive strategies will have different persuasive effectiveness; (2) Adding positive emotion to a message that leads to a better overall user experience could increase persuasive effectiveness. The affective computing or emotion information was added to the experiment using emoticons. The initial results of a pilot study show that computer-mediated communication channels along with various persuasive strategies can affect the persuasive effectiveness to varying degrees. These results also shows that adding a positive emoticon to a message leads to a better user experience which increases the overall persuasive effectiveness of a system.

  4. Strategies for Improving Power in School-Randomized Studies of Professional Development.

    PubMed

    Kelcey, Ben; Phelps, Geoffrey

    2013-12-01

    Group-randomized designs are well suited for studies of professional development because they can accommodate programs that are delivered to intact groups (e.g., schools), the collaborative nature of professional development, and extant teacher/school assignments. Though group designs may be theoretically favorable, prior evidence has suggested that they may be challenging to conduct in professional development studies because well-powered designs will typically require large sample sizes or expect large effect sizes. Using teacher knowledge outcomes in mathematics, we investigated when and the extent to which there is evidence that covariance adjustment on a pretest, teacher certification, or demographic covariates can reduce the sample size necessary to achieve reasonable power. Our analyses drew on multilevel models and outcomes in five different content areas for over 4,000 teachers and 2,000 schools. Using these estimates, we assessed the minimum detectable effect sizes for several school-randomized designs with and without covariance adjustment. The analyses suggested that teachers' knowledge is substantially clustered within schools in each of the five content areas and that covariance adjustment for a pretest or, to a lesser extent, teacher certification, has the potential to transform designs that are unreasonably large for professional development studies into viable studies. © The Author(s) 2014.

  5. An advanced control strategy of an electrical--powered hospital bed.

    PubMed

    Nguyen, Huy Hoang; Nguyen, Tuan Nghia; Clout, Raymont; Nguyen, Hung T

    2014-01-01

    This paper develops a multivariable control technique for low-level control of an intelligent hospital bed. First, multivariable hospital bed models, nominal, upper bounded and lower bounded models, are obtained via an experimental identification procedure. Based on the obtained nominal model, the triangular diagonal dominance (TDD) decoupling technique is applied to reduce a complex multivariable system into a series of scalar systems. For each scalar system, an online adaptive control strategy is then developed to cope with system uncertainties. Compared to the conventional control method, real-time experimental results showed that our proposed multivariable control technique achieved better performance. Experimental results also confirmed that desirable system performance was guaranteed under system uncertainty conditions.

  6. Metal Chelation as a Powerful Strategy to Probe Cellular Circuitry Governing Fungal Drug Resistance and Morphogenesis

    PubMed Central

    Averette, Anna F.; Lee, Soo Chan; Kim, Taeyup; Bahn, Yong-Sun; Robbins, Nicole; Heitman, Joseph; Cowen, Leah E.

    2016-01-01

    Fungal pathogens have evolved diverse strategies to sense host-relevant cues and coordinate cellular responses, which enable virulence and drug resistance. Defining circuitry controlling these traits opens new opportunities for chemical diversity in therapeutics, as the cognate inhibitors are rarely explored by conventional screening approaches. This has great potential to address the pressing need for new therapeutic strategies for invasive fungal infections, which have a staggering impact on human health. To explore this approach, we focused on a leading human fungal pathogen, Candida albicans, and screened 1,280 pharmacologically active compounds to identify those that potentiate the activity of echinocandins, which are front-line therapeutics that target fungal cell wall synthesis. We identified 19 compounds that enhance activity of the echinocandin caspofungin against an echinocandin-resistant clinical isolate, with the broad-spectrum chelator DTPA demonstrating the greatest synergistic activity. We found that DTPA increases susceptibility to echinocandins via chelation of magnesium. Whole genome sequencing of mutants resistant to the combination of DTPA and caspofungin identified mutations in the histidine kinase gene NIK1 that confer resistance to the combination. Functional analyses demonstrated that DTPA activates the mitogen-activated protein kinase Hog1, and that NIK1 mutations block Hog1 activation in response to both caspofungin and DTPA. The combination has therapeutic relevance as DTPA enhanced the efficacy of caspofungin in a mouse model of echinocandin-resistant candidiasis. We found that DTPA not only reduces drug resistance but also modulates morphogenesis, a key virulence trait that is normally regulated by environmental cues. DTPA induced filamentation via depletion of zinc, in a manner that is contingent upon Ras1-PKA signaling, as well as the transcription factors Brg1 and Rob1. Thus, we establish a new mechanism by which metal chelation

  7. Monitored Natural Attenuation as a Remediation Strategy for Nuclear Power Plant Applications

    NASA Astrophysics Data System (ADS)

    Kim, K.; Bushart, S.

    2009-12-01

    A NRC Information Notice (IN 2006-13) was produced to inform holders of nuclear operating licenses “of the occurrence of radioactive contamination of ground water at multiple facilities due to undetected leakage from facility structures, systems, or components (SSCs) that contain or transport radioactive fluids” so that they could consider actions, as appropriate, to avoid similar problems. To reinforce their commitment to environmental stewardship the nuclear energy industry has committed to improving management of situations that have the potential to lead to the inadvertent release of radioactive fluids. This Industry Groundwater Protection Initiative, finalized in June 2007 as [NEI 07-07], calls for implementation and improvement of on-site groundwater monitoring programs and enhanced communications with stakeholders and regulators about situations related to inadvertent releases. EPRI developed its Groundwater Protection Program to provide the nuclear energy industry with the technical support needed to implement the Industry Groundwater Initiative. An objective of the EPRI Groundwater Protection Program is to provide the nuclear industry with technically sound guidance for implementing and enhancing on-site groundwater monitoring programs. EPRI, in collaboration with the EPRI Groundwater Protection Committee of utility members, developed the EPRI Groundwater Protection Guidelines for Nuclear Power Plants (EPRI Report 1015118, November 2007), which provides site-specific guidance for implementing a technically sound groundwater monitoring program. The guidance applies a graded approach for nuclear plants to tailor a technically effective and cost efficient groundwater monitoring program to the site’s hydrogeology and risk for groundwater contamination. As part of the Groundwater Protection Program, EPRI is also investigating innovative remediation technologies for addressing low-level radioactive contamination in soils and groundwater at nuclear power

  8. Investigation of neural-net based control strategies for improved power system dynamic performance

    SciTech Connect

    Sobajic, D.J.

    1995-12-31

    The ability to accurately predict the behavior of a dynamic system is of essential importance in monitoring and control of complex processes. In this regard recent advances in neural-net base system identification represent a significant step toward development and design of a new generation of control tools for increased system performance and reliability. The enabling functionality is the one of accurate representation of a model of a nonlinear and nonstationary dynamic system. This functionality provides valuable new opportunities including: (1) The ability to predict future system behavior on the basis of actual system observations, (2) On-line evaluation and display of system performance and design of early warning systems, and (3) Controller optimization for improved system performance. In this presentation, we discuss the issues involved in definition and design of learning control systems and their impact on power system control. Several numerical examples are provided for illustrative purpose.

  9. The Northeastern United States Energy-Water Nexus: Climate Change Impacts and Alternative Water Management Strategies for the Power Sector

    NASA Astrophysics Data System (ADS)

    Miara, A.; Macknick, J.; Vorosmarty, C. J.; Cohen, S. M.; Rosenzweig, B.

    2014-12-01

    The Northeastern United States (NE) relies heavily on thermoelectric power plants (90% of total capacity) to provide electricity to more than 70 million people. This region's power plants require consistent, large volumes of water at sufficiently cold temperatures to generate electricity efficiently, and withdraw approximately 10.5 trillion gallons of water annually. Previous findings indicate that assessments of future electricity pathways must account for water availability, water temperature and the changing climate, as changes in these conditions may limit operational efficiency in the future. To account for such electric system vulnerabilities, we have created a link between an electricity system capacity expansion model (ReEDS) and a hydrologic model that is coupled to a power plant simulation model (FrAMES-TP2M) that allows for a new approach to analyze electricity system development, performance, and environmental impacts. Together, these coupled tools allow us to estimate electricity development and operations in the context of a changing climate and impacts on the seasonal spatial and temporal variability of water resources, downstream thermal effluents that cause plant-to-plant interferences and harm aquatic habitat, economic costs of water conservation methods and associated carbon emissions. In this study, we test and compare a business-as-usual strategy with three alternative water management scenarios that include changes in cooling technologies and water sources utilized for the years 2014-2050. Results of these experiments can provide useful insight into the feasibility of the electricity expansion scenarios in terms of associated water use and thermal impacts, carbon emissions, the cost of generating electricity, and also highlight the importance of accounting for water resources in future power sector planning and performance assessments.

  10. Nash equilibrium strategy in the deregulated power industry and comparing its lost welfare with Iran wholesale electricity market

    NASA Astrophysics Data System (ADS)

    Mousavi, Seyed Hosein; Nazemi, Ali; Hafezalkotob, Ashkan

    2016-07-01

    With the increasing use of different types of auctions in market designing, modeling of participants' behaviors to evaluate the market structure is one of the main discussions in the studies related to the deregulated power industries. In this article, we apply an approach of the optimal bidding behavior to the Iran wholesale electricity market as a restructured electric power industry and model how the participants of the market bid in the spot electricity market. The problem is formulated analytically using the Nash equilibrium concept composed of large numbers of players having discrete and very large strategy spaces. Then, we compute and draw supply curve of the competitive market in which all generators' proposed prices are equal to their marginal costs and supply curve of the real market in which the pricing mechanism is pay-as-bid. We finally calculate the lost welfare or inefficiency of the Nash equilibrium and the real market by comparing their supply curves with the competitive curve. We examine 3 cases on November 24 (2 cases) and July 24 (1 case), 2012. It is observed that in the Nash equilibrium on November 24 and demand of 23,487 MW, there are 212 allowed plants for the first case (plants are allowed to choose any quantity of generation except one of them that should be equal to maximum Power) and the economic efficiency or social welfare of Nash equilibrium is 2.77 times as much as the real market. In addition, there are 184 allowed plants for the second case (plants should offer their maximum power with different prices) and the efficiency or social welfare of Nash equilibrium is 3.6 times as much as the real market. On July 24 and demand of 42,421 MW, all 370 plants should generate maximum energy due to the high electricity demand that the economic efficiency or social welfare of the Nash equilibrium is about 2 times as much as the real market.

  11. A Strategy of Suppressing the Underground Impact Scattered Current in Power Grid by Using Insulation Baffle

    NASA Astrophysics Data System (ADS)

    Zhan, Qinghua; Chen, Zhucheng; Li, Hongtao; Liu, Yijun; Mei, Cheng; He, Zhijie

    2017-05-01

    In order to solve the accidents happened in the ponds or other special places around the tower which were caused by the diffusion current after lightning stroke the transmission tower, the protection measures for the problem tower in the area of Guangdong Province which occurred dead fish in the pond in thunderstorm weather were studied in this paper. The COMSOL mutiphysics simulation software was used in order to calculate the electromagnetic environment of the diffusion situation by grounding device after lightning stroke the power transmission tower. Study concluded that the safe distance between the fish pond and grounding device of transmission tower is 14 meter. The effects of the length and depth or stayed a gap of the insulation baffle on the fish in the fish pond were discussed. The protection method of the insulation baffle has important practical significance to the protection of the grounding device for diffusion current, and can provide some engineering guidance and basis for the grounding arrangement and transformation of the high voltage transmission line tower.

  12. Alternative strategies for exercise critical power estimation in patients with COPD.

    PubMed

    Malaguti, Carla; Nery, Luiz E; Dal Corso, Simone; De Fuccio, Marcelo Bicalho; Lerario, Maria Cristina; Cendon, Sonia; Neder, J Alberto

    2006-01-01

    Exercise critical power (CP) has been shown to represent the highest sustainable work rate (WR) in patients with chronic obstructive pulmonary disease (COPD). Parameter estimation, however, depends on 4 high-intensity tests performed, on different days, to the limit of tolerance (T(lim)). In order to establish a milder protocol that would be more suitable for disabled patients, we contrasted CP derived from 4, 3 and 2 tests (CP4, CP3 and CP2) in 8 males with moderate COPD. In addition, CP was calculated from 2 single-day tests performed on an inverse sequence (CP(2AB) and CP(2BA)): CP values within 5 W from CP4 were assumed as "clinically-acceptable" estimates. We found that [CP4-CP3] and [CP4-CP2] differences were within 5 W in 8 and 6 patients, respectively (95% confidence interval of the differences = -1.3 to 3.5 W and -11.5 to 6.5 W). There was a systematic decline on T(lim) when an exercise bout was performed after a previous test on the same day (P<0.05). Consequently, substantial differences were found between CP4 and any of the CP estimates obtained from single-day tests. In conclusion, clinically-acceptable estimates of CP can be obtained by using 3 or, in most circumstances, 2 constant WR tests in patients with moderate COPD--provided that they are not performed on the same day.

  13. In-vessel melt retention as a severe accident management strategy for the Loviisa Nuclear Power Plant

    SciTech Connect

    Kymaelaeinen, O.; Tuomisto, H.; Theofanous, T.G.

    1997-02-01

    The concept of lower head coolability and in-vessel retention of corium has been approved as a basic element of the severe accident management strategy for IVO`s Loviisa Plant (VVER-440) in Finland. The selected approach takes advantage of the unique features of the plant such as low power density, reactor pressure vessel without penetrations at the bottom and ice-condenser containment which ensures flooded cavity in all risk significant sequences. The thermal analyses, which are supported by experimental program, demonstrate that in Loviisa the molten corium on the lower head of the reactor vessel is coolable externally with wide margins. This paper summarizes the approach and the plant modifications being implemented. During the approval process some technical concerns were raised, particularly with regard to thermal loadings caused by contact of cool cavity water and hot corium with the reactor vessel. Resolution of these concerns is also discussed.

  14. Two-trait-locus linkage analysis: A powerful strategy for mapping complex genetic traits

    SciTech Connect

    Schork, N.J.; Boehnke, M. ); Terwilliger, J.D.; Ott, J. )

    1993-11-01

    Nearly all diseases mapped to date follow clear Mendelian, single-locus segregation patterns. In contrast, many common familial diseases such as diabetes, psoriasis, several forms of cancer, and schizophrenia are familial and appear to have a genetic component but do not exhibit simple Mendelian transmission. More complex models are required to explain the genetics of these important diseases. In this paper, the authors explore two-trait-locus, two-marker-locus linkage analysis in which two trait loci are mapped simultaneously to separate genetic markers. The authors compare the utility of this approach to standard one-trait-locus, one-marker-locus linkage analysis with and without allowance for heterogeneity. The authors also compare the utility of the two-trait-locus, two-marker-locus analysis to two-trait-locus, one-marker-locus linkage analysis. For common diseases, pedigrees are often bilineal, with disease genes entering via two or more unrelated pedigree members. Since such pedigrees often are avoided in linkage studies, the authors also investigate the relative information content of unilineal and bilineal pedigrees. For the dominant-or-recessive and threshold models that the authors consider, the authors find that two-trait-locus, two-marker-locus linkage analysis can provide substantially more linkage information, as measured by expected maximum lod score, than standard one-trait-locus, one-marker-locus methods, even allowing for heterogeneity, while, for a dominant-or-dominant generating model, one-locus models that allow for heterogeneity extract essentially as much information as the two-trait-locus methods. For these three models, the authors also find that bilineal pedigrees provide sufficient linkage information to warrant their inclusion in such studies. The authors discuss strategies for assessing the significance of the two linkages assumed in two-trait-locus, two-marker-locus models. 37 refs., 1 fig., 4 tabs.

  15. Xenon Acquisition Strategies for High-Power Electric Propulsion NASA Missions

    NASA Technical Reports Server (NTRS)

    Herman, Daniel A.; Unfried, Kenneth G.

    2015-01-01

    Solar electric propulsion (SEP) has been used for station-keeping of geostationary communications satellites since the 1980s. Solar electric propulsion has also benefitted from success on NASA Science Missions such as Deep Space One and Dawn. The xenon propellant loads for these applications have been in the 100s of kilograms range. Recent studies performed for NASA's Human Exploration and Operations Mission Directorate (HEOMD) have demonstrated that SEP is critically enabling for both near-term and future exploration architectures. The high payoff for both human and science exploration missions and technology investment from NASA's Space Technology Mission Directorate (STMD) are providing the necessary convergence and impetus for a 30-kilowatt-class SEP mission. Multiple 30-50- kilowatt Solar Electric Propulsion Technology Demonstration Mission (SEP TDM) concepts have been developed based on the maturing electric propulsion and solar array technologies by STMD with recent efforts focusing on an Asteroid Redirect Robotic Mission (ARRM). Xenon is the optimal propellant for the existing state-of-the-art electric propulsion systems considering efficiency, storability, and contamination potential. NASA mission concepts developed and those proposed by contracted efforts for the 30-kilowatt-class demonstration have a range of xenon propellant loads from 100s of kilograms up to 10,000 kilograms. This paper examines the status of the xenon industry worldwide, including historical xenon supply and pricing. The paper will provide updated information on the xenon market relative to previous papers that discussed xenon production relative to NASA mission needs. The paper will discuss the various approaches for acquiring on the order of 10 metric tons of xenon propellant to support potential near-term NASA missions. Finally, the paper will discuss acquisitions strategies for larger NASA missions requiring 100s of metric tons of xenon will be discussed.

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

    PubMed

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

    2015-09-01

    During movement tasks, patients with medial compartment knee osteoarthritis use compensatory strategies to minimise the joint load of the affected leg. Movement strategies of the knees and trunk have been investigated, but less is known about movement strategies of the pelvis during advancing functional tasks, and how these strategies are associated with leg extension power. The aim of the study was to investigate pelvic movement strategies and leg extension power in patients with end-stage medial compartment knee osteoarthritis compared with controls. 57 patients (mean age 65.6 years) scheduled for medial uni-compartmental knee arthroplasty, and 29 age and gender matched controls were included in this cross-sectional study. Leg extension power was tested with the Nottingham Leg Extension Power-Rig. Pelvic range of motion was derived from an inertia-based measurement unit placed over the sacrum bone during walking, stair climbing and stepping. Patients had lower leg extension power than controls (20-39 %, P < 0.01) and used greater pelvic range of motion during stair and step ascending and descending (P ≤ 0.03, except for pelvic range of motion in the frontal plane during ascending, P > 0.06). Furthermore, an inverse association (coefficient: -0.03 to -0.04; R (2) = 13-22 %) between leg extension power and pelvic range of motion during stair and step descending was found in the patients. Compared to controls, patients with medial compartment knee osteoarthritis use greater pelvic movements during advanced functional performance tests, particularly when these involve descending tasks. Further studies should investigate if it is possible to alter these movement strategies by an intervention aimed at increasing strength and power for the patients.

  17. Quantifying the efficiency and equity implications of power plant air pollution control strategies in the United States

    SciTech Connect

    Levy, J.I.; Wilson, A.M.; Zwack, L.M.

    2007-05-15

    We modeled the public health benefits and the change in the spatial inequality of health risk for a number of hypothetical control scenarios for power plants in the United States to determine optimal control strategies. We simulated various ways by which emission reductions of sulfur dioxide (SO{sub 2}), nitrogen oxides, and fine particulate matter (PM2.5) could be distributed to reach national emissions caps. We applied a source-receptor matrix to determine the PM2.5 concentration changes associated with each control scenario and estimated the mortality reductions. We estimated changes in the spatial inequality of health risk using the Atkinson index and other indicators, following previously derived axioms for measuring health risk inequality. In our baseline model, benefits ranged from 17,000-21,000 fewer premature deaths per year across control scenarios. Scenarios with greater health benefits also tended to have greater reductions in the spatial inequality of health risk, as many sources with high health benefits per unit emissions of SO{sub 2} were in areas with high background PM2.5 concentrations. Sensitivity analyses indicated that conclusions were generally robust to the choice of indicator and other model specifications. Our analysis demonstrates an approach for formally quantifying both the magnitude and spatial distribution of health benefits of pollution control strategies, allowing for joint consideration of efficiency and equity.

  18. The Economic Merits of Flexible Carbon Capture and Sequestration as a Compliance Strategy with the Clean Power Plan.

    PubMed

    Craig, Michael T; Jaramillo, Paulina; Zhai, Haibo; Klima, Kelly

    2017-02-07

    Carbon capture and sequestration (CCS) may be a key technology for achieving large CO2 emission reductions. Relative to "normal" CCS, "flexible" CCS retrofits include solvent storage that allows the generator to temporarily reduce the CCS parasitic load and increase the generator's net efficiency, capacity, and ramp rate. Due to this flexibility, flexible CCS generators provide system benefits that normal CCS generators do not, which could make flexible CCS an economic CO2 emission reduction strategy. Here, we estimate the system-level cost effectiveness of reducing CO2 emissions with flexible CCS compared to redispatching (i.e., substituting gas- for coal-fired electricity generation), wind, and normal CCS under the Clean Power Plan (CPP) and a hypothetical more stringent CO2 emission reduction target ("stronger CPP"). Using a unit commitment and economic dispatch model, we find flexible CCS achieves more cost-effective emission reductions than normal CCS under both reduction targets, indicating that policies that promote CCS should encourage flexible CCS. However, flexible CCS is less cost effective than wind under both reduction targets and less and more cost effective than redispatching under the CPP and stronger CPP, respectively. Thus, CCS will likely be a minor CPP compliance strategy but may play a larger role under a stronger emission reduction target.

  19. Modelling of a Vector-current Controlled UPFC and Comprehensive Comparison with the Power-angle Control Strategy

    NASA Astrophysics Data System (ADS)

    Ren, Bixing; Du, Wenjuan; Cai, Hui; Wang, Haifeng; Wang, Xiangfeng; Zhang, Jianpeng

    2017-05-01

    This paper establishes the non-linear dynamic mathematical model of the vector-current controlled unified power flow controller (UPFC) and the linearized model of the UPFC is derived in detail afterwards for the analysis of dynamic performance stability. Then, the paper carries out deep investigations on the comparison and analysis for the above two control strategies applied to the UPFC in the aspects of dynamic interaction and auxiliary damping effect. The relative gain array (RGA) method is used to assess the dynamic interactions among the multiple control functions of the UPFC, and damping torque analysis (DTA) method is used to compare the damping performance of the UPFC auxiliary damping controller. The results of quantitative comparison by RGA and DTA analysis show that the vector-current controlled UPFC exhibits better decoupling characteristic among multiple control loops, while the power-angle controlled UPFC exhibits better auxiliary damping performance. Conclusions are further validated by the non-linear simulation results via a two-area four-machine system.

  20. The Einstein Observatory catalog of IPC x ray sources. Volume 5E: Right ascension range 12h 00m to 15h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics, which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers, and data useful for calculating upper limits and fluxes.

  1. The Einstein Observatory catalog of IPC x ray sources. Volume 4E: Right ascension range 08h 00m to 11h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images, The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentaion describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers, and data useful for calculating upper limits and fluxes.

  2. The Einstein Observatory catalog of IPC x ray sources. Volume 6E: Right ascension range 16h 00m to 19h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2 launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics, which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers, and data useful for calculating upper limits and fluxes.

  3. The Einstein Observatory catalog of IPC x ray sources. Volume 3E: Right ascension range 04h 00m to 07h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers and data useful for calculating upper limits and fluxes.

  4. The Einstein Observatory catalog of IPC x ray sources. Volume 7E: Right ascension range 20h 00m to 23h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers, and data useful for calculating upper limits and fluxes.

  5. The Einstein Observatory catalog of IPC x ray sources. Volume 2E: Right ascension range 00h 00m to 03h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers and data useful for calculating upper limits and fluxes.

  6. Hybrid Electric Power Train and Control Strategies Automotive Technology Education (GATE) Program

    SciTech Connect

    Andrew Frank

    2006-05-31

    Plug-in hybrid electric vehicles (PHEV) offer societal benefits through their ability to displace the use of petroleum fuels. Petroleum fuels represent a polluting and politically destabilizing energy carrier. PHEV technologies can move transportation away from petroleum fuel sources by enabling domestically generated electricity and liquids bio-fuels to serve as a carrier for transportation energy. Additionally, the All-Electric-Range (AER) offered by PHEVs can significantly reduce demand for expensive and polluting liquid fuels. The GATE funding received during the 1998 through 2004 funding cycle by the UC Davis Hybrid Electric Vehicle Center (HEVC) was used to advance and train researchers in PHEV technologies. GATE funding was used to construct a rigorous PHEV curriculum, provide financial support for HEVC researchers, and provide material support for research efforts. A rigorous curriculum was developed through the UC Davis Mechanical and Aeronautical Engineering Department to train HEVC researchers. Students' research benefited from this course work by advancing the graduate student researchers' understanding of key PHEV design considerations. GATE support assisted HEVC researchers in authoring technical articles and producing patents. By supporting HEVC researchers multiple Master's theses were written as well as journal articles and publications. The topics from these publications include Continuously Variable Transmission control strategies and PHEV cross platform controls software development. The GATE funding has been well used to advance PHEV systems. The UC Davis Hybrid Electric Vehicle Center is greatly appreciative for the opportunities GATE funding provided. The goals and objectives for the HEVC GATE funding were to nourish engineering research in PHEV technologies. The funding supplied equipment needed to allow researchers to investigate PHEV design sensitivities and to further optimize system components. Over a dozen PHEV researchers benefited

  7. Waste Management Strategy for Dismantling Waste to Reduce Costs for Power Plant Decommissioning - 13543

    SciTech Connect

    Larsson, Arne; Lidar, Per; Bergh, Niklas; Hedin, Gunnar

    2013-07-01

    Decommissioning of nuclear power plants generates large volumes of radioactive or potentially radioactive waste. The proper management of the dismantling waste plays an important role for the time needed for the dismantling phase and thus is critical to the decommissioning cost. An efficient and thorough process for inventorying, characterization and categorization of the waste provides a sound basis for the planning process. As part of comprehensive decommissioning studies for Nordic NPPs, Westinghouse has developed the decommissioning inventories that have been used for estimations of the duration of specific work packages and the corresponding costs. As part of creating the design basis for a national repository for decommissioning waste, the total production of different categories of waste packages has also been predicted. Studsvik has developed a risk based concept for categorization and handling of the generated waste using six different categories with a span from extremely small risk for radiological contamination to high level waste. The two companies have recently joined their skills in the area of decommissioning on selected market in a consortium named 'ndcon' to further strengthen the proposed process. Depending on the risk for radiological contamination or the radiological properties and other properties of importance for waste management, treatment routes are proposed with well-defined and proven methods for on-site or off-site treatment, activity determination and conditioning. The system is based on a graded approach philosophy aiming for high confidence and sustainability, aiming for re-use and recycling where found applicable. The objective is to establish a process where all dismantled material has a pre-determined treatment route. These routes should through measurements, categorization, treatment, conditioning, intermediate storage and final disposal be designed to provide a steady, un-disturbed flow of material to avoid interruptions. Bottle

  8. Delivery of Terrigenous Material to Submarine Fans: Biological Evidence of Local, Staged, and Possibly Full Canyon Sediment Transport Down the Ascension-Monterey Canyon System Off Central California, USA

    NASA Astrophysics Data System (ADS)

    McGann, M.

    2014-12-01

    Submarine canyons are instrumental in transporting sediment from coastal regions to deep-sea fans. Mean grain size, distribution, and sorting have been used to characterize these deposits, but they provide little information on where sediment transport was initiated or the delivery processes involved. Fortunately, the entrained biological constituents have unique environmental signatures that are more precise proxies for source areas than are mineral grains alone. They may identify a single biofacies deposit (SBD) resulting from local sediment transport such as storm waves, peak river discharge, breaking of internal waves, canyon wall sloughing, or hemipelagic deposition, or a displaced, multiple biofacies deposit (MBD) containing several biofacies where sediment is transported from one biofacies to another, is caught behind a slump that acts as a dam, remains there long enough for the local fauna to become established, and then this combined assemblage is transported further downslope when the dam breaks. Multiple episodes of this "staged" storage-and-release process occur sequentially so as to move the sediment progressively down the canyon. Rarely, exceptionally large triggers such as earthquakes, intense storm disturbances, and catastrophic failure of canyon walls result in full canyon flushing events, entraining numerous biofacies during a single rapid descent. These events can be differentiated in recent deposits by the presence of living specimens representing distinct biofacies or in historic records by dating individual biofacies within a turbidite. A 19,000 year record from the Ascension-Monterey Canyon system (core S3-15G, 36°23.53'N, 123°20.52'W; 3491 m) captured hemipelagic mud interspersed with turbiditic sand and silt transported to lower bathyal depths. The relative abundance of displaced benthic foraminifera was found to correlate positively with grain size (75% in cross-bedded turbiditic sands, 39% in laminated turbiditic sands, and 15% in

  9. Hydro-economic performances of streamflow withdrawal strategies: the case of small run-of-river power plants

    NASA Astrophysics Data System (ADS)

    Basso, Stefano; Lazzaro, Gianluca; Schirmer, Mario; Botter, Gianluca

    2014-05-01

    River flows withdrawals to supply small run-of-river hydropower plants have been increasing significantly in recent years - particularly in the Alpine area - as a consequence of public incentives aimed at enhancing energy production from renewable sources. This growth further raised the anthropic pressure in areas traditionally characterized by an intense exploitation of water resources, thereby triggering social conflicts among local communities, hydropower investors and public authorities. This brought to the attention of scientists and population the urgency for novel and quantitative tools for assessing the hydrologic impact of these type of plants, and trading between economic interests and ecologic concerns. In this contribution we propose an analytical framework that allows for the estimate of the streamflow availability for hydropower production and the selection of the run-of-river plant capacity, as well as the assessment of the related profitability and environmental impacts. The method highlights the key role of the streamflow variability in the design process, by showing the significance control of the coefficient of variation of daily flows on the duration of the optimal capacity of small run-of-river plants. Moreover, the analysis evidences a gap between energy and economic optimizations, which may result in the under-exploitation of the available hydropower potential at large scales. The disturbances to the natural flow regime produced between the intake and the outflow of run-of-river power plants are also estimated within the proposed framework. The altered hydrologic regime, described through the probability distribution and the correlation function of streamflows, is analytically expressed as a function of the natural regime for different management strategies. The deviations from pristine conditions of a set of hydrologic statistics are used, jointly with an economic index, to compare environmental and economic outcomes of alternative plant

  10. Optimal race strategy for a 200-m flying sprint in a human-powered vehicle: A case study of a world-record attempt.

    PubMed

    de Koning, Jos J; van der Zweep, Cees-Jan; Cornelissen, Jesper; Kuiper, Bouke

    2013-03-01

    Optimal pacing strategy was determined for breaking the world speed record on a human-powered vehicle (HPV) using an energy-flow model in which the rider's physical capacities, the vehicle's properties, and the environmental conditions were included. Power data from world-record attempts were compared with data from the model, and race protocols were adjusted to the results from the model. HPV performance can be improved by using an energy-flow model for optimizing race strategy. A biphased in-run followed by a sprint gave best results.

  11. Limnological and ecological methods: approaches, and sampling strategies for middle Xingu River in the area of influence of future Belo Monte Power Plant.

    PubMed

    Tundisi, J G; Matsumura-Tundisi, T; Tundisi, J E M; Faria, C R L; Abe, D S; Blanco, F; Rodrigues Filho, J; Campanelli, L; Sidagis Galli, C; Teixeira-Silva, V; Degani, R; Soares, F S; Gatti Junior, P

    2015-08-01

    In this paper the authors describe the limnological approaches, the sampling methodology, and strategy adopted in the study of the Xingu River in the area of influence of future Belo Monte Power Plant. The river ecosystems are characterized by unidirectional current, highly variable in time depending on the climatic situation the drainage pattern an hydrological cycle. Continuous vertical mixing with currents and turbulence, are characteristic of these ecosystems. All these basic mechanisms were taken into consideration in the sampling strategy and field work carried out in the Xingu River Basin, upstream and downstream the future Belo Monte Power Plant Units.

  12. Quantifying the Efficiency and Equity Implications of Power Plant Air Pollution Control Strategies in the United States

    PubMed Central

    Levy, Jonathan I.; Wilson, Andrew M.; Zwack, Leonard M.

    2007-01-01

    Background In deciding among competing approaches for emissions control, debates often hinge on the potential tradeoffs between efficiency and equity. However, previous health benefits analyses have not formally addressed both dimensions. Objectives We modeled the public health benefits and the change in the spatial inequality of health risk for a number of hypothetical control scenarios for power plants in the United States to determine optimal control strategies. Methods We simulated various ways by which emission reductions of sulfur dioxide (SO2), nitrogen oxides, and fine particulate matter (particulate matter < 2.5 μm in diameter; PM2.5) could be distributed to reach national emissions caps. We applied a source–receptor matrix to determine the PM2.5 concentration changes associated with each control scenario and estimated the mortality reductions. We estimated changes in the spatial inequality of health risk using the Atkinson index and other indicators, following previously derived axioms for measuring health risk inequality. Results In our baseline model, benefits ranged from 17,000–21,000 fewer premature deaths per year across control scenarios. Scenarios with greater health benefits also tended to have greater reductions in the spatial inequality of health risk, as many sources with high health benefits per unit emissions of SO2 were in areas with high background PM2.5 concentrations. Sensitivity analyses indicated that conclusions were generally robust to the choice of indicator and other model specifications. Conclusions Our analysis demonstrates an approach for formally quantifying both the magnitude and spatial distribution of health benefits of pollution control strategies, allowing for joint consideration of efficiency and equity. PMID:17520062

  13. Quantifying the efficiency and equity implications of power plant air pollution control strategies in the United States.

    PubMed

    Levy, Jonathan I; Wilson, Andrew M; Zwack, Leonard M

    2007-05-01

    In deciding among competing approaches for emissions control, debates often hinge on the potential tradeoffs between efficiency and equity. However, previous health benefits analyses have not formally addressed both dimensions. We modeled the public health benefits and the change in the spatial inequality of health risk for a number of hypothetical control scenarios for power plants in the United States to determine optimal control strategies. We simulated various ways by which emission reductions of sulfur dioxide (SO(2)), nitrogen oxides, and fine particulate matter (particulate matter < 2.5 microm in diameter; PM(2.5)) could be distributed to reach national emissions caps. We applied a source-receptor matrix to determine the PM(2.5) concentration changes associated with each control scenario and estimated the mortality reductions. We estimated changes in the spatial inequality of health risk using the Atkinson index and other indicators, following previously derived axioms for measuring health risk inequality. In our baseline model, benefits ranged from 17,000-21,000 fewer premature deaths per year across control scenarios. Scenarios with greater health benefits also tended to have greater reductions in the spatial inequality of health risk, as many sources with high health benefits per unit emissions of SO(2) were in areas with high background PM(2.5) concentrations. Sensitivity analyses indicated that conclusions were generally robust to the choice of indicator and other model specifications. Our analysis demonstrates an approach for formally quantifying both the magnitude and spatial distribution of health benefits of pollution control strategies, allowing for joint consideration of efficiency and equity.

  14. Identification of filter management strategy in fluid power systems under uncertainty: an interval-fuzzy parameter integer nonlinear programming method

    NASA Astrophysics Data System (ADS)

    Nie, S. L.; Hu, B.; Li, Y. P.; Hu, Z.; Huang, G. H.

    2011-03-01

    An interval-fuzzy integer nonlinear programming (IFINP) method is developed for the identification of filter allocation and replacement strategies in a fluid power system (FPS) under uncertainty. It can handle uncertainties expressed as interval-fuzzy values that exist in the left- and right-hand sides of constraints as well as in the objective function. The developed method is applied to a case of planning filter allocation and replacement strategies under uncertainty for a FPS with a single circuit. A piecewise linearisation approach is used to convert the nonlinear problem of FPS into a linear one. The generated fuzzy solutions will be used to analyse and interpret the multiple decision alternatives under various system conditions, and thus help decision-makers to make a compromise among the system contamination level, system cost, satisfaction degrees and system-failure risks under different contaminant ingression/generation rates. The results demonstrate that the suction and return filters can effectively reduce the contamination level associated with a low system cost, but the FPS will take lots of failure risk when the contaminant ingression/generation rate is high; and the combination of suction and pressure filters can bring the lowest system cost with more security instead. Furthermore, comparisons for the optimised solutions are made among IFINP, interval-parameter integer nonlinear programming and deterministic linear programming also. Generally, the IFINP method can effectively reduce the total design and operation cost of the filtration system when contaminants ingression/generation rate is high, and it could be extended to the lubricating system.

  15. A wavelet-fuzzy logic based energy management strategy for a fuel cell/battery/ultra-capacitor hybrid vehicular power system

    NASA Astrophysics Data System (ADS)

    Erdinc, O.; Vural, B.; Uzunoglu, M.

    Due to increasing concerns on environmental pollution and depleting fossil fuels, fuel cell (FC) vehicle technology has received considerable attention as an alternative to the conventional vehicular systems. However, a FC system combined with an energy storage system (ESS) can display a preferable performance for vehicle propulsion. As the additional ESS can fulfill the transient power demand fluctuations, the fuel cell can be downsized to fit the average power demand without facing peak loads. Besides, braking energy can be recovered by the ESS. This study focuses on a vehicular system powered by a fuel cell and equipped with two secondary energy storage devices: battery and ultra-capacitor (UC). However, an advanced energy management strategy is quite necessary to split the power demand of a vehicle in a suitable way for the on-board power sources in order to maximize the performance while promoting the fuel economy and endurance of hybrid system components. In this study, a wavelet and fuzzy logic based energy management strategy is proposed for the developed hybrid vehicular system. Wavelet transform has great capability for analyzing signals consisting of instantaneous changes like a hybrid electric vehicle (HEV) power demand. Besides, fuzzy logic has a quite suitable structure for the control of hybrid systems. The mathematical and electrical models of the hybrid vehicular system are developed in detail and simulated using MATLAB ®, Simulink ® and SimPowerSystems ® environments.

  16. Using genetic algorithms to determine near-optimal pricing, investment and operating strategies in the electric power industry

    NASA Astrophysics Data System (ADS)

    Wu, Dongjun

    Network industries have technologies characterized by a spatial hierarchy, the "network," with capital-intensive interconnections and time-dependent, capacity-limited flows of products and services through the network to customers. This dissertation studies service pricing, investment and business operating strategies for the electric power network. First-best solutions for a variety of pricing and investment problems have been studied. The evaluation of genetic algorithms (GA, which are methods based on the idea of natural evolution) as a primary means of solving complicated network problems, both w.r.t. pricing: as well as w.r.t. investment and other operating decisions, has been conducted. New constraint-handling techniques in GAs have been studied and tested. The actual application of such constraint-handling techniques in solving practical non-linear optimization problems has been tested on several complex network design problems with encouraging initial results. Genetic algorithms provide solutions that are feasible and close to optimal when the optimal solution is know; in some instances, the near-optimal solutions for small problems by the proposed GA approach can only be tested by pushing the limits of currently available non-linear optimization software. The performance is far better than several commercially available GA programs, which are generally inadequate in solving any of the problems studied in this dissertation, primarily because of their poor handling of constraints. Genetic algorithms, if carefully designed, seem very promising in solving difficult problems which are intractable by traditional analytic methods.

  17. Integration of health care organizations: using the power strategies of horizontal and vertical integration in public and private health systems.

    PubMed

    Thaldorf, Carey; Liberman, Aaron

    2007-01-01

    Integration in health care attempts to provide all elements in a seamless continuum of care. Pressures influencing development of system-wide integration primarily come from unsustainable cost increases in the United States over the later part of the 20th century and the early 21st century. Promoters of health care integration assume that it will lead to increased effectiveness and quality of care while concurrently increasing cost-effectiveness and possibly facilitating cost savings. The primary focus of this literature review is on the Power Strategies of Horizontal and Vertical Integration. The material presented suggests that vertical integration is most effective in markets where the partners involved are larger and dominant in the regions they serve. The research has also found that integrating health care networks had little or no significant effect on improving overall organizational efficiencies or profits. Capital investment in information technologies still is cost prohibitive and outweighs its benefits to integration efficiencies in the private sector; however, there are some indications of improvements in publicly provided health care. Further research is needed to understand the reasons the public sector has had greater success in improving effectiveness and efficiency through integration than the private sector.

  18. Joint US/Russian study on the development of a decommissioning strategy plan for RBMK-1000 unit No. 1 at the Leningrad Nuclear Power Plant

    SciTech Connect

    1997-12-01

    The objective of this joint U.S./Russian study was to develop a safe, technically feasible, economically acceptable strategy for decommissioning Leningrad Nuclear Power Plant (LNPP) Unit No. 1 as a representative first-generation RBMK-1000 reactor. The ultimate goal in developing the decommissioning strategy was to select the most suitable decommissioning alternative and end state, taking into account the socioeconomic conditions, the regulatory environment, and decommissioning experience in Russia. This study was performed by a group of Russian and American experts led by Kurchatov Institute for the Russian efforts and by the Pacific Northwest National Laboratory for the U.S. efforts and for the overall project.

  19. Modeling nexus of urban heat island mitigation strategies with electricity/power usage and consumer costs: a case study for Phoenix, Arizona, USA

    NASA Astrophysics Data System (ADS)

    Silva, Humberto; Fillpot, Baron S.

    2016-11-01

    A reduction in both power and electricity usage was determined using a previously validated zero-dimensional energy balance model that implements mitigation strategies used to reduce the urban heat island (UHI) effect. The established model has been applied to show the change in urban characteristic temperature when executing four common mitigation strategies: increasing the overall (1) emissivity, (2) vegetated area, (3) thermal conductivity, and (4) albedo of the urban environment in a series of increases by 5, 10, 15, and 20% from baseline values. Separately, a correlation analysis was performed involving meteorological data and total daily energy (TDE) consumption where the 24-h average temperature was shown to have the greatest correlation to electricity service data in the Phoenix, Arizona, USA, metropolitan region. A methodology was then developed for using the model to predict TDE consumption reduction and corresponding cost-saving analysis when implementing the four mitigation strategies. The four modeled UHI mitigation strategies, taken in combination, would lead to the largest percent reduction in annual energy usage, where increasing the thermal conductivity is the single most effective mitigation strategy. The single least effective mitigation strategy, increasing the emissivity by 5% from the baseline value, resulted in an average calculated reduction of about 1570 GWh in yearly energy usage with a corresponding 157 million dollar cost savings. When the four parameters were increased in unison by 20% from baseline values, an average calculated reduction of about 2050 GWh in yearly energy usage was predicted with a corresponding 205 million dollar cost savings.

  20. Surveillance strategies for Classical Swine Fever in wild boar – a comprehensive evaluation study to ensure powerful surveillance

    PubMed Central

    Schulz, Katja; Peyre, Marisa; Staubach, Christoph; Schauer, Birgit; Schulz, Jana; Calba, Clémentine; Häsler, Barbara; Conraths, Franz J.

    2017-01-01

    Surveillance of Classical Swine Fever (CSF) should not only focus on livestock, but must also include wild boar. To prevent disease transmission into commercial pig herds, it is therefore vital to have knowledge about the disease status in wild boar. In the present study, we performed a comprehensive evaluation of alternative surveillance strategies for Classical Swine Fever (CSF) in wild boar and compared them with the currently implemented conventional approach. The evaluation protocol was designed using the EVA tool, a decision support tool to help in the development of an economic and epidemiological evaluation protocol for surveillance. To evaluate the effectiveness of the surveillance strategies, we investigated their sensitivity and timeliness. Acceptability was analysed and finally, the cost-effectiveness of the surveillance strategies was determined. We developed 69 surveillance strategies for comparative evaluation between the existing approach and the novel proposed strategies. Sampling only within sub-adults resulted in a better acceptability and timeliness than the currently implemented strategy. Strategies that were completely based on passive surveillance performance did not achieve the desired detection probability of 95%. In conclusion, the results of the study suggest that risk-based approaches can be an option to design more effective CSF surveillance strategies in wild boar. PMID:28266576

  1. Surveillance strategies for Classical Swine Fever in wild boar - a comprehensive evaluation study to ensure powerful surveillance.

    PubMed

    Schulz, Katja; Peyre, Marisa; Staubach, Christoph; Schauer, Birgit; Schulz, Jana; Calba, Clémentine; Häsler, Barbara; Conraths, Franz J

    2017-03-07

    Surveillance of Classical Swine Fever (CSF) should not only focus on livestock, but must also include wild boar. To prevent disease transmission into commercial pig herds, it is therefore vital to have knowledge about the disease status in wild boar. In the present study, we performed a comprehensive evaluation of alternative surveillance strategies for Classical Swine Fever (CSF) in wild boar and compared them with the currently implemented conventional approach. The evaluation protocol was designed using the EVA tool, a decision support tool to help in the development of an economic and epidemiological evaluation protocol for surveillance. To evaluate the effectiveness of the surveillance strategies, we investigated their sensitivity and timeliness. Acceptability was analysed and finally, the cost-effectiveness of the surveillance strategies was determined. We developed 69 surveillance strategies for comparative evaluation between the existing approach and the novel proposed strategies. Sampling only within sub-adults resulted in a better acceptability and timeliness than the currently implemented strategy. Strategies that were completely based on passive surveillance performance did not achieve the desired detection probability of 95%. In conclusion, the results of the study suggest that risk-based approaches can be an option to design more effective CSF surveillance strategies in wild boar.

  2. Optimal design and control strategies for novel combined heat and power (CHP) fuel cell systems. Part I of II, datum design conditions and approach.

    SciTech Connect

    Colella, Whitney G.

    2010-06-01

    Energy network optimization (ENO) models identify new strategies for designing, installing, and controlling stationary combined heat and power (CHP) fuel cell systems (FCSs) with the goals of (1) minimizing electricity and heating costs for building owners and (2) reducing emissions of the primary greenhouse gas (GHG) - carbon dioxide (CO{sub 2}). A goal of this work is to employ relatively inexpensive simulation studies to discover more financially and environmentally effective approaches for installing CHP FCSs. ENO models quantify the impact of different choices made by power generation operators, FCS manufacturers, building owners, and governments with respect to two primary goals - energy cost savings for building owners and CO{sub 2} emission reductions. These types of models are crucial for identifying cost and CO{sub 2} optima for particular installations. Optimal strategies change with varying economic and environmental conditions, FCS performance, the characteristics of building demand for electricity and heat, and many other factors. ENO models evaluate both 'business-as-usual' and novel FCS operating strategies. For the scenarios examined here, relative to a base case of no FCSs installed, model results indicate that novel strategies could reduce building energy costs by 25% and CO{sub 2} emissions by 80%. Part I of II articles discusses model assumptions and methodology. Part II of II articles illustrates model results for a university campus town and generalizes these results for diverse communities.

  3. Comparison of design strategies for a three-arm clinical trial with time-to-event endpoint: Power, time-to-analysis, and operational aspects.

    PubMed

    Asikanius, Elina; Rufibach, Kaspar; Bahlo, Jasmin; Bieska, Gabriele; Burger, Hans Ulrich

    2016-11-01

    To optimize resources, randomized clinical trials with multiple arms can be an attractive option to simultaneously test various treatment regimens in pharmaceutical drug development. The motivation for this work was the successful conduct and positive final outcome of a three-arm randomized clinical trial primarily assessing whether obinutuzumab plus chlorambucil in patients with chronic lympocytic lymphoma and coexisting conditions is superior to chlorambucil alone based on a time-to-event endpoint. The inference strategy of this trial was based on a closed testing procedure. We compare this strategy to three potential alternatives to run a three-arm clinical trial with a time-to-event endpoint. The primary goal is to quantify the differences between these strategies in terms of the time it takes until the first analysis and thus potential approval of a new drug, number of required events, and power. Operational aspects of implementing the various strategies are discussed. In conclusion, using a closed testing procedure results in the shortest time to the first analysis with a minimal loss in power. Therefore, closed testing procedures should be part of the statistician's standard clinical trials toolbox when planning multiarm clinical trials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Analysis of Strategies for Multiple Emissions from Electric Power SO2, NOX, CO2, Mercury and RPS

    EIA Publications

    2001-01-01

    At the request of the Subcommittee, the Energy Information Administration prepared an initial report that focused on the impacts of reducing power sector NOx, SO2, and CO2 emissions. The current report extends the earlier analysis to add the impacts of reducing power sector mercury emissions and introducing renewable portfolio standard (RPS) requirements.

  5. Adaptations in bilateral mechanical power patterns during obstacle avoidance reveal distinct control strategies for limb elevation versus limb progression.

    PubMed

    Niang, Assane E S; McFadyen, Bradford J

    2004-04-01

    The present study investigated the adaptations of specific power bursts during the combined contexts of the proximity (lead vs. trail limb) and height of an obstruction in relation to limb elevation versus progression. Ten young, adult, male subjects walked at their natural speed during unobstructed walking and the bilateral avoidance of moderate and high obstacles. Hip flexor generation power was unaffected by obstacle height for the leading limb and always delayed for the trailing limb. The knee extensor absorption power burst at toe-off was also eliminated for the trailing limb and was found to reappear in mid-swing. Few differences were seen for ankle push-off power. The results suggest that the hip joint is dedicated to limb advancement only, while the knee joint is directly involved in limb elevation and the control of multiarticular effects.

  6. Coordinated Control Strategy of a Battery Energy Storage System to Support a Wind Power Plant Providing Multi-Timescale Frequency Ancillary Services

    DOE PAGES

    Tan, Jin; Zhang, Yingchen

    2017-02-02

    With increasing penetrations of wind generation on electric grids, wind power plants (WPPs) are encouraged to provide frequency ancillary services (FAS); however, it is a challenge to ensure that variable wind generation can reliably provide these ancillary services. This paper proposes using a battery energy storage system (BESS) to ensure the WPPs' commitment to FAS. This method also focuses on reducing the BESS's size and extending its lifetime. In this paper, a state-machine-based coordinated control strategy is developed to utilize a BESS to support the obliged FAS of a WPP (including both primary and secondary frequency control). This method takesmore » into account the operational constraints of the WPP (e.g., real-time reserve) and the BESS (e.g., state of charge [SOC], charge and discharge rate) to provide reliable FAS. Meanwhile, an adaptive SOC-feedback control is designed to maintain SOC at the optimal value as much as possible and thus reduce the size and extend the lifetime of the BESS. In conclusion, the effectiveness of the control strategy is validated with an innovative, multi-area, interconnected power system simulation platform that can mimic realistic power systems operation and control by simulating real-time economic dispatch, regulating reserve scheduling, multi-area automatic generation control, and generators' dynamic response.« less

  7. Identifying/Quantifying Environmental Trade-offs Inherent in GHG Reduction Strategies for Coal-Fired Power.

    PubMed

    Schivley, Greg; Ingwersen, Wesley W; Marriott, Joe; Hawkins, Troy R; Skone, Timothy J

    2015-07-07

    Improvements to coal power plant technology and the cofired combustion of biomass promise direct greenhouse gas (GHG) reductions for existing coal-fired power plants. Questions remain as to what the reduction potentials are from a life cycle perspective and if it will result in unintended increases in impacts to air and water quality and human health. This study provides a unique analysis of the potential environmental impact reductions from upgrading existing subcritical pulverized coal power plants to increase their efficiency, improving environmental controls, cofiring biomass, and exporting steam for industrial use. The climate impacts are examined in both a traditional-100 year GWP-method and a time series analysis that accounts for emission and uptake timing over the life of the power plant. Compared to fleet average pulverized bed boilers (33% efficiency), we find that circulating fluidized bed boilers (39% efficiency) may provide GHG reductions of about 13% when using 100% coal and reductions of about 20-37% when cofiring with 30% biomass. Additional greenhouse gas reductions from combined heat and power are minimal if the steam coproduct displaces steam from an efficient natural gas boiler. These upgrades and cofiring biomass can also reduce other life cycle impacts, although there may be increased impacts to water quality (eutrophication) when using biomass from an intensely cultivated source. Climate change impacts are sensitive to the timing of emissions and carbon sequestration as well as the time horizon over which impacts are considered, particularly for long growth woody biomass.

  8. A New Vision for Teacher Professional Growth & Support: Six Steps to a More Powerful School System Strategy

    ERIC Educational Resources Information Center

    Education Resource Strategies, 2013

    2013-01-01

    One of a series of Education Resource Strategies (ERS) publications and tools, this paper explores important ways to organize and invest in Professional Growth & Support that strengthen teaching capacity and effectiveness at the system level. It draws on research, ERS experience with urban school systems nationwide, and detailed analyses of…

  9. Increasing Parent Involvement Knowledge and Strategies at the Preservice Level: The Power in Using a Systematic Professional Development Approach

    ERIC Educational Resources Information Center

    Ferrara, Margaret M.

    2009-01-01

    This study describes various strategies used by a university educator to integrate parent involvement curriculum into pre-existing teacher preparation courses. This curriculum infusion was not only effective in increasing preservice teacher knowledge but also in raising course instructors' level of awareness about the importance and necessity of…

  10. Partnering with Parents to Ask the Right Questions: A Powerful Strategy for Strengthening School-Family Partnerships

    ERIC Educational Resources Information Center

    Santana, Luz; Rothstein, Dan; Bain, Agnes

    2016-01-01

    This book presents a simple strategy on how educators can build effective partnerships with parents. It distills complex, important ideas on effective civic participation into an easy-to-learn process that teaches parents two fundamental skills they can use to support the education of their children, monitor their progress, and advocate for them:…

  11. Implications of the Third Industrial Revolution on the Elements of National Power and Their Impact on National Security Strategy

    DTIC Science & Technology

    1992-03-16

    resources we have available. Certainly, with respect to the technology viewpoint, the strategy can and must be improved. 26 ENDNOTES 1. I. M. Hymes , "The...19-21. Hymes , I. M. "The Revolution in Manufacturing." In Windows On A New World: The Third Industrial Revolution. ed. Joseph Finkelstein. New York

  12. Partnering with Parents to Ask the Right Questions: A Powerful Strategy for Strengthening School-Family Partnerships

    ERIC Educational Resources Information Center

    Santana, Luz; Rothstein, Dan; Bain, Agnes

    2016-01-01

    This book presents a simple strategy on how educators can build effective partnerships with parents. It distills complex, important ideas on effective civic participation into an easy-to-learn process that teaches parents two fundamental skills they can use to support the education of their children, monitor their progress, and advocate for them:…

  13. Definitional Hegemony as a Public Relations Strategy: The Rhetoric of the Nuclear Power Industry after Three Mile Island.

    ERIC Educational Resources Information Center

    Dionisopoulos, George N.; Crable, Richard E.

    1988-01-01

    Examines (1) definitional hegemony as one of several rhetorical options available to issue managers; (2) the post-accident rhetorical context of the Three Mile Island nuclear crisis; and (3) the specific strategies utilized to deal with this crisis. Assesses the nuclear industry's public relations efforts. (MS)

  14. Definitional Hegemony as a Public Relations Strategy: The Rhetoric of the Nuclear Power Industry after Three Mile Island.

    ERIC Educational Resources Information Center

    Dionisopoulos, George N.; Crable, Richard E.

    1988-01-01

    Examines (1) definitional hegemony as one of several rhetorical options available to issue managers; (2) the post-accident rhetorical context of the Three Mile Island nuclear crisis; and (3) the specific strategies utilized to deal with this crisis. Assesses the nuclear industry's public relations efforts. (MS)

  15. Increasing Parent Involvement Knowledge and Strategies at the Preservice Level: The Power in Using a Systematic Professional Development Approach

    ERIC Educational Resources Information Center

    Ferrara, Margaret M.

    2009-01-01

    This study describes various strategies used by a university educator to integrate parent involvement curriculum into pre-existing teacher preparation courses. This curriculum infusion was not only effective in increasing preservice teacher knowledge but also in raising course instructors' level of awareness about the importance and necessity of…

  16. America’s Post-9/11 Grand Strategy: Matching the Response to the Threat, and Implications for U.S. National Power

    DTIC Science & Technology

    2012-05-17

    reporting burden for this collection of information 1s estimated to average 1 hour per response, including the time for reviewing instructions. searching...RETURN YOUR FORM TO THE ABOVE ORGANIZATION. 1 . REPORT DATE (00-MM-YYYY) 12. REPORT TYPE 11-05-20 12 Monograph 4. TITLE AND SUBTITLE A merica’s Post...911 1 Grand Strategy: Matching the Response to the Threat, and Implications for U.S. National Power 6. AUTHOR(S) Lt Col Roy P. Fatur 7

  17. Biodiesel Drives Florida Power & Light's EPAct Alternative Compliance Strategy; EPAct Alternative Fuel Transportation Program: Success Story (Fact Sheet)

    SciTech Connect

    Not Available

    2010-05-01

    This success story highlights how Florida Power & Light Company has successfully complied with the Energy Policy Act of 1992 (EPAct) through Alternative Compliance using biodiesel technologies and how it has become a biofuel leader, reducing petroleum use and pollutant emissions throughout Florida.

  18. Global Strategies for Optimizing the Reliability and Performance of U.S. Army Mobile Power Transfer Systems

    DTIC Science & Technology

    2013-08-01

    entails better modeling of the vehicle usage which will allow us to estimate the likelihood of a vehicle being available to connect to the microgrid ...vehicle platform itself, but to external systems and platforms. All power systems can be connected wirelessly, or through a microgrid . Therefore...restoration and contingency operations. Because a microgrid is designed for a period of time, our optimization problem considers factors such as cost

  19. Reducing start-up time and minimizing energy losses of Microbial Fuel Cells using Maximum Power Point Tracking strategy

    NASA Astrophysics Data System (ADS)

    Molognoni, Daniele; Puig, Sebastià; Balaguer, M. Dolors; Liberale, Alessandro; Capodaglio, Andrea G.; Callegari, Arianna; Colprim, Jesús

    2014-12-01

    Microbial Fuel Cells (MFCs) are considered to be an environmental friendly energy conversion technology. The main limitations that delay their industrialization include low current and power densities achievable and long start-up times. Maximum Power Point Tracking (MPPT) has been proposed as a method to enhance MFCs electrical performances. However, the specialized literature is still lacking of experimental works on scaled-up reactors and/or real wastewater utilization. This study evaluates the impact of a MPPT system applied to MFCs treating swine wastewater in terms of start-up time and long-term performance. For this purpose, two replicate cells were compared, one with applied MPPT control and one working with fixed resistance. Both MFCs were continuously fed with swine wastewater to validate the control system under real and dynamic conditions. The study demonstrated that the automatic resistance control was able to reduce the start-up time of about one month. Moreover, MPPT system increased of 40% the Coulombic efficiency at steady-state conditions, reduced energy losses associated with anode and cathode reactions and limited methanogenic activity in the anode chamber. A power density of 5.0 ± 0.2 W m-3 NAC was achieved feeding the system at an organic loading rate of 10 kg COD m-3 d-1.

  20. Sampling strategies and materials for investigating large reactive particle complaints from Valley Village homeowners near a coal-fired power plant

    SciTech Connect

    Chang, A.; Davis, H.; Frazar, B.; Haines, B.

    1997-12-31

    This paper will present Phase 3`s sampling strategies, techniques, methods and substrates for assisting the District to resolve the complaints involving yellowish-brown staining and spotting of homes, cars, etc. These spots could not be easily washed off and some were permanent. The sampling strategies for the three phases were based on Phase 1 -- the identification of the reactive particles conducted in October, 1989 by APCD and IITRI, Phase 2 -- a study of the size distribution and concentration as a function of distance and direction of reactive particle deposition conducted by Radian and LG and E, and Phase 3 -- the determination of the frequency of soiling events over a full year`s duration conducted in 1995 by APCD and IITRI. The sampling methods included two primary substrates -- ACE sheets and painted steel, and four secondary substrates -- mailbox, aluminum siding, painted wood panels and roof tiles. The secondary substrates were the main objects from the Valley Village complaints. The sampling technique included five Valley Village (VV) soiling/staining assessment sites and one southwest of the power plant as background/upwind site. The five VV sites northeast of the power plant covered 50 degrees span sector and 3/4 miles distance from the stacks. Hourly meteorological data for wind speeds and wind directions were collected. Based on this sampling technique, there were fifteen staining episodes detected. Nine of them were in summer, 1995.

  1. [Evaluation of the diagnostic power of 3 methods for assaying free T4. Results in the diagnostic strategy of hyperthyroidism].

    PubMed

    Fragu, P; Noel, M; Patois, E; Delarue, J C; Paugam-Capelle, J; Parmentier, C

    1985-01-01

    The free thyroxin (FT4) tests of Amersham, Clinical Assay and Corning Medical were evaluated in 240 patients who were suspected of hyperthyroidism. The diagnostic performances of the Corning method were of less value while those of the other methods were equivalent to that obtained with the free thyroxin index for an average cost reduced. Furthermore our results show that T3 determination is better than T4 determination in patients who remained doubtful after FT4. However the development of ultra-short methods of measurement of total thyroid hormone blood levels using fluorescence polarization could lead to reconsider the diagnostic strategy of hyperthyroidism.

  2. State strategies of governance in biomedical innovation: aligning conceptual approaches for understanding 'Rising Powers' in the global context

    PubMed Central

    2011-01-01

    Background 'Innovation' has become a policy focus in its own right in many states as they compete to position themselves in the emerging knowledge economies. Innovation in biomedicine is a global enterprise in which 'Rising Power' states figure prominently, and which undoubtedly will re-shape health systems and health economies globally. Scientific and technological innovation processes and policies raise difficult issues in the domains of science/technology, civil society, and the economic and healthcare marketplace. The production of knowledge in these fields is complex, uncertain, inter-disciplinary and inter-institutional, and subject to a continuing political struggle for advantage. As part of this struggle, a wide variety of issues - regulation, intellectual property, ethics, scientific boundaries, healthcare market formation - are raised and policy agendas negotiated. Methods A range of social science disciplines and approaches have conceptualised such innovation processes. Against a background of concepts such as the competition state and the developmental state, and national innovation systems, we give an overview of a range of approaches that have potential for advancing understanding of governance of global life science and biomedical innovation, with special reference to the 'Rising Powers', in order to examine convergences and divergences between them. Conceptual approaches that we focus on include those drawn from political science/political economy, sociology of technology; Innovation Studies and Science & Technology Studies. The paper is part of a project supported by the UK ESRC's Rising Powers programme. Results We show convergences and complementarities between the approaches discussed, and argue that the role of the national state itself has become relatively neglected in much of the relevant theorising. Conclusions We conclude that an approach is required that enables innovation and governance to be seen as 'co-producing' each other in a multi

  3. Strategies for steam handling and H2S abatement at geothermal power plants in the geysers area of Northern California

    NASA Astrophysics Data System (ADS)

    Morris, W. F.; Stephens, F. B.

    1981-08-01

    Strict limitations on the emission of H2S from new geothermal power plants in The Geysers area of northern California were imposed by Lake and Northern Sonoma County Air Pollution Control Districts. Lake County, under new source review rules, stipulated that specific technologies should be utilized to limit H2S emissions to 5 lb/h as a condition for determination of compliance. The status of these technologies as well as other ongoing technology development efforts to conserve steam and abate H2S are evaluated.

  4. Hybrid Stochastic Search Technique based Suboptimal AGC Regulator Design for Power System using Constrained Feedback Control Strategy

    NASA Astrophysics Data System (ADS)

    Ibraheem, Omveer, Hasan, N.

    2010-10-01

    A new hybrid stochastic search technique is proposed to design of suboptimal AGC regulator for a two area interconnected non reheat thermal power system incorporating DC link in parallel with AC tie-line. In this technique, we are proposing the hybrid form of Genetic Algorithm (GA) and simulated annealing (SA) based regulator. GASA has been successfully applied to constrained feedback control problems where other PI based techniques have often failed. The main idea in this scheme is to seek a feasible PI based suboptimal solution at each sampling time. The feasible solution decreases the cost function rather than minimizing the cost function.

  5. Power Teaching

    ERIC Educational Resources Information Center

    Fluellen, Jerry E., Jr.

    2007-01-01

    Power Teaching weaves four factors into a seamless whole: standards, teaching thinking, research based strategies, and critical inquiry. As a prototype in its first year of development with an urban fifth grade class, the power teaching model connects selected district standards, thinking routines from Harvard University Project Zero Research…

  6. Planning for future uncertainties in electric power generation; An analysis of transitional strategies for reduction of carbon and sulfur emissions

    SciTech Connect

    Tabors, R.D.; Monroe, B.L. III . Lab. for Electromagnetic and Electronic Systems)

    1991-11-01

    The objective of this paper is to identify strategies for the U.S. electric utility industry for reduction of both acid rain producing and global warming gasses. The research used the EPRI Electric Generation Expansion Analysis System (EGEAS) utility optimization/simulation modeling structure and the EPRI developed regional utilities. It focuses on the North East and East Central region of the U.S. Strategies identified were fuel switching -- predominantly between coal and natural gas, mandated emission limits, and a carbon tax. The overall conclusions of the study are that using less (conservation) will always benefit Carbon Emissions but may or may not benefit Acid Rain emissions by the off setting forces of improved performance of new plant as opposed to reduced overall consumption of final product. Results of the study are highly utility and regional demand specific. The study showed, however, that significant reductions in both acid rain and global warming gas production could be achieved with relatively small increases in the overall cost of production of electricity and that the current dispatch logics available to the utility control rooms were adequate to reschedule dispatch to meet these objectives.

  7. Evaluating the Effect of Upgrade, Control and Development Strategies on Robustness and Failure Risk of the Power Transmission Grid

    SciTech Connect

    Newman, David E; Carreras, Benjamin A; Lynch, Vickie E; Dobson, Ian

    2008-01-01

    We use the OPA complex systems model of the power transmission system to investigate the effect of a series of different network upgrade scenarios on the long time dynamics and the probability of large cascading failures. The OPA model represents the power grid at the level of DC load flow and LP generation dispatch and represents blackouts caused by randomly triggered cascading line outages and overloads. We examine the effect of increased component reliability on the long-term risks, the effect of changing operational margins and the effect of redundancy on those same long-term risks. The general result is that while increased reliability of the components decreases the probability of small blackouts, depending on the implementation, it actually can increase the probability of large blackouts. When we instead increase some types of redundancy of the system there is an overall decrease in the large blackouts. As some of these results are counter intuitive these studies suggest that care must be taken when making what seem to be logical upgrade decisions.

  8. Evaluation of steroidomics by liquid chromatography hyphenated to mass spectrometry as a powerful analytical strategy for measuring human steroid perturbations.

    PubMed

    Jeanneret, Fabienne; Tonoli, David; Rossier, Michel F; Saugy, Martial; Boccard, Julien; Rudaz, Serge

    2016-01-22

    This review presents the evolution of steroid analytical techniques, including gas chromatography coupled to mass spectrometry (GC-MS), immunoassay (IA) and targeted liquid chromatography coupled to mass spectrometry (LC-MS), and it evaluates the potential of extended steroid profiles by a metabolomics-based approach, namely steroidomics. Steroids regulate essential biological functions including growth and reproduction, and perturbations of the steroid homeostasis can generate serious physiological issues; therefore, specific and sensitive methods have been developed to measure steroid concentrations. GC-MS measuring several steroids simultaneously was considered the first historical standard method for analysis. Steroids were then quantified by immunoassay, allowing a higher throughput; however, major drawbacks included the measurement of a single compound instead of a panel and cross-reactivity reactions. Targeted LC-MS methods with selected reaction monitoring (SRM) were then introduced for quantifying a small steroid subset without the problems of cross-reactivity. The next step was the integration of metabolomic approaches in the context of steroid analyses. As metabolomics tends to identify and quantify all the metabolites (i.e., the metabolome) in a specific system, appropriate strategies were proposed for discovering new biomarkers. Steroidomics, defined as the untargeted analysis of the steroid content in a sample, was implemented in several fields, including doping analysis, clinical studies, in vivo or in vitro toxicology assays, and more. This review discusses the current analytical methods for assessing steroid changes and compares them to steroidomics. Steroids, their pathways, their implications in diseases and the biological matrices in which they are analysed will first be described. Then, the different analytical strategies will be presented with a focus on their ability to obtain relevant information on the steroid pattern. The future technical

  9. The Nexawatt: A Strategy for Exawatt Peak Power Lasers Based on NIF and NIF-like Beam Lines

    NASA Astrophysics Data System (ADS)

    Barty, C. P. J.

    2016-05-01

    An exawatt-scale, short-pulse amplification architecture based upon a novel pulse compressor arrangement and amplification of long-duration chirped beam pulses is described. This architecture is capable of extracting the full, stored energy of a NIF or NIF-like beam line and in doing so produce from one beam line a near-diffraction-limited, laser pulse whose peak power would exceed 0.2 EW. The architecture is well suited to either low-f-number focusing or to multi-beam, dipole focusing concepts that in principle enable focused intensities in the range of 1026 W/cm2 or 5 orders of magnitude beyond that possible from present PW systems based on chirped pulse amplification.

  10. Filtered sunlight, solar powered phototherapy and other strategies for managing neonatal jaundice in low-resource settings.

    PubMed

    Slusher, Tina M; Day, Louise Tina; Ogundele, Tolulope; Woolfield, Nick; Owa, Joseph Aderinsola

    2017-09-15

    Challenges in treating severe neonatal jaundice in low and middle-income country settings still exist at many levels. These include: a lack of awareness of causes and prevention by families, communities and even sometimes health care professionals; insufficient, ineffective, high quality affordable diagnostic and therapeutic options; limited availability of rehabilitation provision for kernicterus. Collectively these challenges lead to an unacceptably high global morbidity and mortality from severe neonatal jaundice. In the past decade, there has been an explosion of innovations addressing some of these issues and these are increasingly available for scale up. Scientists, healthcare providers, and communities are joining hands to explore educational tools, low cost screening and diagnostic options including at point-of-care and treatment modalities including filtered sunlight and solar powered phototherapy. For the first time, the possibility of eliminating the tragedy of preventable morbidity and mortality from severe NNJ is on the horizon, for all. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Surface charge tunability as a powerful strategy to control electrostatic interaction for high efficiency silencing, using tailored oligopeptide-modified poly(beta-amino ester)s (PBAEs).

    PubMed

    Dosta, Pere; Segovia, Nathaly; Cascante, Anna; Ramos, Victor; Borrós, Salvador

    2015-07-01

    Here we present an extended family of pBAEs that incorporate terminal oligopeptide moieties synthesized from both positive and negative amino acids. Polymer formulations of mixtures of negative and positive oligopeptide-modified pBAEs are capable of condensing siRNA into discrete nanoparticles. We have demonstrated that efficient delivery of nucleic acids in a cell-type dependent manner can be achieved by careful control of the pBAE formulation. In addition, our approach of adding differently charged oligopeptides to the termini of poly(β-amino ester)s is of great interest for the design of tailored complexes having specific features, such as tuneable zeta potential. We anticipate that this surface charge tunability may be a powerful strategy to control unwanted electrostatic interactions, while preserving high silencing efficiency and reduced toxicity.

  12. Photon harvesting, coloring and polarizing in photovoltaic cell integrated color filters: efficient energy routing strategies for power-saving displays

    NASA Astrophysics Data System (ADS)

    Wen, Long; Chen, Qin; Song, Shichao; Yu, Yan; Jin, Lin; Hu, Xin

    2015-07-01

    We describe the integral electro-optical strategies that combine the functionalities of photovoltaic (PV) electricity generation and color filtering as well as polarizing to realize more efficient energy routing in display technology. Unlike the conventional pigment-based filters and polarizers, which absorb substantial amounts of unwanted spectral components and dissipate them in the form of heat, we propose converting the energy of those photons into electricity by constructing PV cell-integrated color filters based on a selectively transmitting aluminum (Al) rear electrode perforated with nanoholes (NHs). Combining with a dielectric-metal-dielectric (DMD) front electrode, the devices were optimized to enable efficient cavity-enhanced photon recycling in the PV functional layers. We perform a comprehensive theoretical and numerical analysis to explore the extraordinary optical transmission (EOT) through the Al NHs and identify basic design rules for achieving structural coloring or polarizing in our PV color filters. We show that the addition of thin photoactive polymer layers on the symmetrically configured Al NH electrode narrows the bandwidth of the EOT-assisted high-pass light filtering due to the strongly damped anti-symmetric coupling of the surface modes excited on the front and rear surface of the Al NHs, which facilitates the whole visible coloring with relatively high purity for the devices. By engineering the cut-off characteristics of the plasmonic waveguide mode supported by the circular or ellipsoidal Al NHs, beyond the photon recycling capacity, PV color filters and PV polarizing color filters that allow polarization-insensitive and strong polarization-anisotropic color filtering were demonstrated. The findings presented here may shed some light on expanding the utilization of PV electricity generation across new-generation energy-saving electrical display devices.

  13. Photon harvesting, coloring and polarizing in photovoltaic cell integrated color filters: efficient energy routing strategies for power-saving displays.

    PubMed

    Wen, Long; Chen, Qin; Song, Shichao; Yu, Yan; Jin, Lin; Hu, Xin

    2015-07-03

    We describe the integral electro-optical strategies that combine the functionalities of photovoltaic (PV) electricity generation and color filtering as well as polarizing to realize more efficient energy routing in display technology. Unlike the conventional pigment-based filters and polarizers, which absorb substantial amounts of unwanted spectral components and dissipate them in the form of heat, we propose converting the energy of those photons into electricity by constructing PV cell-integrated color filters based on a selectively transmitting aluminum (Al) rear electrode perforated with nanoholes (NHs). Combining with a dielectric-metal-dielectric (DMD) front electrode, the devices were optimized to enable efficient cavity-enhanced photon recycling in the PV functional layers. We perform a comprehensive theoretical and numerical analysis to explore the extraordinary optical transmission (EOT) through the Al NHs and identify basic design rules for achieving structural coloring or polarizing in our PV color filters. We show that the addition of thin photoactive polymer layers on the symmetrically configured Al NH electrode narrows the bandwidth of the EOT-assisted high-pass light filtering due to the strongly damped anti-symmetric coupling of the surface modes excited on the front and rear surface of the Al NHs, which facilitates the whole visible coloring with relatively high purity for the devices. By engineering the cut-off characteristics of the plasmonic waveguide mode supported by the circular or ellipsoidal Al NHs, beyond the photon recycling capacity, PV color filters and PV polarizing color filters that allow polarization-insensitive and strong polarization-anisotropic color filtering were demonstrated. The findings presented here may shed some light on expanding the utilization of PV electricity generation across new-generation energy-saving electrical display devices.

  14. Strategy for designing stable and powerful nitrogen-rich high-energy materials by introducing boron atoms.

    PubMed

    Wu, Wen-Jie; Chi, Wei-Jie; Li, Quan-Song; Li, Ze-Sheng

    2017-06-01

    One of the most important aims in the development of high-energy materials is to improve their stability and thus ensure that they are safe to manufacture and transport. In this work, we theoretically investigated open-chain N4B2 isomers using density functional theory in order to find the best way of stabilizing nitrogen-rich molecules. The results show that the boron atoms in these isomers are aligned linearly with their neighboring atoms, which facilitates close packing in the crystals of these materials. Upon comparing the energies of nine N4B2 isomers, we found that the structure with alternating N and B atoms had the lowest energy. Structures with more than one nitrogen atom between two boron atoms had higher energies. The energy of N4B2 increases by about 50 kcal/mol each time it is rearranged to include an extra nitrogen atom between the two boron atoms. More importantly, our results also show that boron atoms stabilize nitrogen-rich molecules more efficiently than carbon atoms do. Also, the combustion of any isomer of N4B2 releases more heat than the corresponding isomer of N4C2 does under well-oxygenated conditions. Our study suggests that the three most stable N4B2 isomers (BN13, BN24, and BN34) are good candidates for high-energy molecules, and it outlines a new strategy for designing stable boron-containing high-energy materials. Graphical abstract The structural characteristics, thermodynamic stabilities, and exothermic properties of nitrogen-rich N4B2 isomers were investigated by means of density functional theory.

  15. On variant strategies to solve the magnitude least squares optimization problem in parallel transmission pulse design and under strict SAR and power constraints.

    PubMed

    Hoyos-Idrobo, A; Weiss, P; Massire, A; Amadon, A; Boulant, N

    2014-03-01

    Parallel transmission is a very promising candidate technology to mitigate the inevitable radio-frequency (RF) field inhomogeneity in magnetic resonance imaging at ultra-high field. For the first few years, pulse design utilizing this technique was expressed as a least squares problem with crude power regularizations aimed at controlling the specific absorption rate (SAR), hence the patient safety. This approach being suboptimal for many applications sensitive mostly to the magnitude of the spin excitation, and not its phase, the magnitude least squares (MLS) problem then was first formulated in 2007. Despite its importance and the availability of other powerful numerical optimization methods, the MLS problem yet has been faced almost exclusively by the pulse designer with the so-called variable exchange method. In this paper, we investigate various two-stage strategies consisting of different initializations and nonlinear programming approaches, and incorporate directly the strict SAR and hardware constraints. Several schemes such as sequential quadratic programming, interior point methods, semidefinite programming and magnitude squared least squares relaxations are studied both in the small and large tip angle regimes with RF and static field maps obtained in vivo on a human brain at 7T. Convergence and robustness of the different approaches are analyzed, and recommendations to tackle this specific problem are finally given. Small tip angle and inversion pulses are returned in a few seconds and in under a minute respectively while respecting the constraints, allowing the use of the proposed approach in routine.

  16. Strategy making and power in environmental assessments. Lessons from the establishment of an out-of-town shopping centre in Vaesteras, Sweden

    SciTech Connect

    Isaksson, Karolina; Storbjoerk, Sofie

    2012-04-15

    This paper seeks to provide deeper insights into how EA ineffectiveness is produced in land use planning practice. This is explored in a study of local development planning in the city of Vaesteras, Sweden. The case in question is the development of a large out-of-town shopping centre, propelled by the establishment of a new IKEA furniture store. The Healey (2007) framework of planning as strategy making is applied as an analytical framework, together with a focus on power-knowledge relations. In the analysis, we identify a range of mechanisms that produced ineffectiveness by limiting the role of environmental knowledge throughout the planning process. The specific mechanisms we identified were related to the overall consensus perspective in local development strategies and plans, a lack of concretisation and integration of various policies and strategies, a range of exclusion mechanisms and an overall focus on mitigation and benefits of the process in question. In practice, these mechanisms were closely intertwined. Our main conclusion is, consequently, that increased effectiveness of EA would require fundamental transformation of the norms, frameworks and routines that implicitly and explicitly guide land use planning in practice. - Highlights: Black-Right-Pointing-Pointer We analyse how EA-ineffectiveness is produced in land use planning practice. Black-Right-Pointing-Pointer Several mechanisms produce EA-ineffectiveness throughout the whole planning process. Black-Right-Pointing-Pointer These mechanisms are often closely intertwined and mutually reinforcing each other. Black-Right-Pointing-Pointer Enhancing EA-effectiveness requires a fundamental shift of the norms, frameworks and routines shaping planning practice.

  17. A precautionary public health protection strategy for the possible risk of childhood leukaemia from exposure to power frequency magnetic fields

    PubMed Central

    2010-01-01

    Background Epidemiological evidence showing a consistent association between the risk of childhood leukaemia and exposure to power frequency magnetic fields has been accumulating. This debate considers the additional precautionary intervention needed to manage this risk, when it exceeds the protection afforded by the exposure guidelines as recommended by the International Commission on Non-Ionizing Radiation Protection. Methods The Bradford-Hill Criteria are guidelines for evaluating the scientific evidence that low frequency magnetic fields cause childhood leukaemia. The criteria are used for assessing the strength of scientific evidence and here have been applied to considering the strength of evidence that exposures to extremely low frequency magnetic fields may increase the risk of childhood leukaemia. The applicability of precaution is considered using the risk management framework outlined in a European Commission (EC) communication on the Precautionary Principle. That communication advises that measures should be proportionate, non-discriminatory, consistent with similar measures already taken, based on an examination of the benefits and costs of action and inaction, and subject to review in the light of new scientific findings. Results The main evidence for a risk is an epidemiological association observed in several studies and meta-analyses; however, the number of highly exposed children is small and the association could be due to a combination of selection bias, confounding and chance. Corroborating experimental evidence is limited insofar as there is no clear indication of harm at the field levels implicated; however, the aetiology of childhood leukaemia is poorly understood. Taking a precautionary approach suggests that low-cost intervention to reduce exposure is appropriate. This assumes that if the risk is real, its impact is likely to be small. It also recognises the consequential cost of any major intervention. The recommendation is controversial

  18. A precautionary public health protection strategy for the possible risk of childhood leukaemia from exposure to power frequency magnetic fields.

    PubMed

    Maslanyj, Myron; Lightfoot, Tracy; Schüz, Joachim; Sienkiewicz, Zenon; McKinlay, Alastair

    2010-11-05

    Epidemiological evidence showing a consistent association between the risk of childhood leukaemia and exposure to power frequency magnetic fields has been accumulating. This debate considers the additional precautionary intervention needed to manage this risk, when it exceeds the protection afforded by the exposure guidelines as recommended by the International Commission on Non-Ionizing Radiation Protection. The Bradford-Hill Criteria are guidelines for evaluating the scientific evidence that low frequency magnetic fields cause childhood leukaemia. The criteria are used for assessing the strength of scientific evidence and here have been applied to considering the strength of evidence that exposures to extremely low frequency magnetic fields may increase the risk of childhood leukaemia. The applicability of precaution is considered using the risk management framework outlined in a European Commission (EC) communication on the Precautionary Principle. That communication advises that measures should be proportionate, non-discriminatory, consistent with similar measures already taken, based on an examination of the benefits and costs of action and inaction, and subject to review in the light of new scientific findings. The main evidence for a risk is an epidemiological association observed in several studies and meta-analyses; however, the number of highly exposed children is small and the association could be due to a combination of selection bias, confounding and chance. Corroborating experimental evidence is limited insofar as there is no clear indication of harm at the field levels implicated; however, the aetiology of childhood leukaemia is poorly understood. Taking a precautionary approach suggests that low-cost intervention to reduce exposure is appropriate. This assumes that if the risk is real, its impact is likely to be small. It also recognises the consequential cost of any major intervention. The recommendation is controversial in that other

  19. Membrane fouling and anti-fouling strategies using RO retentate from a municipal water recycling plant as the feed for osmotic power generation.

    PubMed

    Chen, Si Cong; Amy, Gary L; Chung, Tai-Shung

    2016-01-01

    RO retentate from a municipal water recycling plant is considered as a potential feed stream for osmotic power generation in this paper. The feasibility of using RO retentate from a municipal water recycling plant was examined from two aspects: (a) the membrane fouling propensity of RO retentate, and (b) the efficacy of anti-fouling strategies. The membranes used in this study were the inner selective thin film composite polyethersulfone (TFC/PES) hollow fiber membranes, which possessed a high water permeability and good mechanical strength. Scaling by phosphate salts was found to be one possible inorganic fouling on the innermost layer of the PES membrane, whereas silica fouling was observed to be the governing fouling on the outmost surface of the PES membrane. Two anti-fouling pretreatments, i.e., pH adjustment and anti-scalant pre-treatment for the feed stream, were studied and found to be straightforward and effective. Using RO retentate at pH 7.2 as the feed and 1 M NaCl as the draw solution, the average power density was 7.3 W/m(2) at 20 bar. The average power density increased to 12.6 W/m(2) by modifying RO retentate with an initial pH value of 5.5 using HCl and to 13.4 W/m(2) by adding 1.1 mM ethylenediaminetetraacetic acid (EDTA). Moreover, the flux recovery of the fouled membranes, without the indicated pretreatments, reached 84.9% using deionized (DI) water flushing and 95.0% using air bubbling under a high crossflow velocity of 23.3 cm/s (Re = 2497) for 30 min. After pretreatment by pH adjustment, the flux recovery increased to 94.6% by DI water flushing and 100.0% by air bubbling. After pretreatment by adding 1.1 mM EDTA into RO retentate, flux was almost fully restored by physical cleaning by DI water flushing and air bubbling. These results provide insight into developing an effective pretreatment by either pH adjustment or EDTA addition before PRO and physical cleaning methods by DI water flushing and air bubbling for membrane used in

  20. A lab-in-a-droplet bioassay strategy for centrifugal microfluidics with density difference pumping, power to disc and bidirectional flow control.

    PubMed

    Wang, Guanghui; Ho, Ho-Pui; Chen, Qiulan; Yang, Alice Kar-Lai; Kwok, Ho-Chin; Wu, Shu-Yuen; Kong, Siu-Kai; Kwan, Yiu-Wa; Zhang, Xuping

    2013-09-21

    In this paper, we present a lab-in-a-droplet bioassay strategy for a centrifugal microfluidics or lab-on-a-disc (LOAD) platform with three important advancements including density difference pumping, power to disc and bidirectional flow control. First, with the water based bioassay droplets trapped in a micro-channel filled with mineral oil, centrifugal force due to the density difference between the water and oil phases actuates droplet movement while the oil based medium remains stationary. Second, electricity is coupled to the rotating disc through a split-core transformer, thus enabling on-chip real-time heating in selected areas as desired and wireless programmable functionality. Third, an inertial mechanical structure is proposed to achieve bidirectional flow control within the spinning disc. The droplets can move back and forth between two heaters upon changing the rotational speed. Our platform is an essential and versatile solution for bioassays such as those involving DNA amplification, where localized temperature cycling is required. Finally, without the loss of generality, we demonstrate the functionality of our platform by performing real-time polymerase chain reaction (RT-PCR) in a linear microchannel made with PTFE (Teflon) micro-tubing.

  1. Improving motor activity assessment in depression: which sensor placement, analytic strategy and diurnal time frame are most powerful in distinguishing patients from controls and monitoring treatment effects.

    PubMed

    Reichert, Markus; Lutz, Alexander; Deuschle, Michael; Gilles, Maria; Hill, Holger; Limberger, Matthias F; Ebner-Priemer, Ulrich W

    2015-01-01

    Abnormalities in motor activity represent a central feature in major depressive disorder. However, measurement issues are poorly understood, limiting the use of objective measurement of motor activity for diagnostics and treatment monitoring. To improve measurement issues, especially sensor placement, analytic strategies and diurnal effects, we assessed motor activity in depressed patients at the beginning (MD; n=27) and after anti-depressive treatment (MD-post; n=18) as well as in healthy controls (HC; n=16) using wrist- and chest-worn accelerometers. We performed multiple analyses regarding sensor placements, extracted features, diurnal variation, motion patterns and posture to clarify which parameters are most powerful in distinguishing patients from controls and monitoring treatment effects. Whereas most feature-placement combinations revealed significant differences between groups, acceleration (wrist) distinguished MD from HC (d=1.39) best. Frequency (vertical axis chest) additionally differentiated groups in a logistic regression model (R2=0.54). Accordingly, both amplitude (d=1.16) and frequency (d=1.04) showed alterations, indicating reduced and decelerated motor activity. Differences between MD and HC in gestures (d=0.97) and walking (d=1.53) were found by data analysis from the wrist sensor. Comparison of motor activity at the beginning and after MD-treatment largely confirms our findings. Sample size was small, but sufficient for the given effect sizes. Comparison of depressed in-patients with non-hospitalized controls might have limited motor activity differences between groups. Measurement of wrist-acceleration can be recommended as a basic technique to capture motor activity in depressed patients as it records whole body movement and gestures. Detailed analyses showed differences in amplitude and frequency denoting that depressed patients walked less and slower.

  2. Improving Motor Activity Assessment in Depression: Which Sensor Placement, Analytic Strategy and Diurnal Time Frame Are Most Powerful in Distinguishing Patients from Controls and Monitoring Treatment Effects

    PubMed Central

    Deuschle, Michael; Gilles, Maria; Hill, Holger; Limberger, Matthias F.; Ebner-Priemer, Ulrich W.

    2015-01-01

    Background Abnormalities in motor activity represent a central feature in major depressive disorder. However, measurement issues are poorly understood, limiting the use of objective measurement of motor activity for diagnostics and treatment monitoring. Methods To improve measurement issues, especially sensor placement, analytic strategies and diurnal effects, we assessed motor activity in depressed patients at the beginning (MD; n=27) and after anti-depressive treatment (MD-post; n=18) as well as in healthy controls (HC; n=16) using wrist- and chest-worn accelerometers. We performed multiple analyses regarding sensor placements, extracted features, diurnal variation, motion patterns and posture to clarify which parameters are most powerful in distinguishing patients from controls and monitoring treatment effects. Results Whereas most feature-placement combinations revealed significant differences between groups, acceleration (wrist) distinguished MD from HC (d=1.39) best. Frequency (vertical axis chest) additionally differentiated groups in a logistic regression model (R2=0.54). Accordingly, both amplitude (d=1.16) and frequency (d=1.04) showed alterations, indicating reduced and decelerated motor activity. Differences between MD and HC in gestures (d=0.97) and walking (d=1.53) were found by data analysis from the wrist sensor. Comparison of motor activity at the beginning and after MD-treatment largely confirms our findings. Limitations Sample size was small, but sufficient for the given effect sizes. Comparison of depressed in-patients with non-hospitalized controls might have limited motor activity differences between groups. Conclusions Measurement of wrist-acceleration can be recommended as a basic technique to capture motor activity in depressed patients as it records whole body movement and gestures. Detailed analyses showed differences in amplitude and frequency denoting that depressed patients walked less and slower. PMID:25885258

  3. A passive heat maintenance strategy implemented during a simulated half-time improves lower body power output and repeated sprint ability in professional Rugby Union players.

    PubMed

    Russell, Mark; West, Daniel J; Briggs, Marc A; Bracken, Richard M; Cook, Christian J; Giroud, Thibault; Gill, Nicholas; Kilduff, Liam P

    2015-01-01

    Reduced physical performance has been observed following the half-time period in team sports players, likely due to a decrease in muscle temperature during this period. We examined the effects of a passive heat maintenance strategy employed between successive exercise bouts on core temperature (Tcore) and subsequent exercise performance. Eighteen professional Rugby Union players completed this randomised and counter-balanced study. After a standardised warm-up (WU) and 15 min of rest, players completed a repeated sprint test (RSSA 1) and countermovement jumps (CMJ). Thereafter, in normal training attire (Control) or a survival jacket (Passive), players rested for a further 15 min (simulating a typical half-time) before performing a second RSSA (RSSA 2) and CMJ's. Measurements of Tcore were taken at baseline, post-WU, pre-RSSA 1, post-RSSA 1 and pre-RSSA 2. Peak power output (PPO) and repeated sprint ability was assessed before and after the simulated half-time. Similar Tcore responses were observed between conditions at baseline (Control: 37.06±0.05°C; Passive: 37.03±0.05°C) and for all other Tcore measurements taken before half-time. After the simulated half-time, the decline in Tcore was lower (-0.74±0.08% vs. -1.54±0.06%, p<0.001) and PPO was higher (5610±105 W vs. 5440±105 W, p<0.001) in the Passive versus Control condition. The decline in PPO over half-time was related to the decline in Tcore (r = 0.632, p = 0.005). In RSSA 2, best, mean and total sprint times were 1.39±0.17% (p<0.001), 0.55±0.06% (p<0.001) and 0.55±0.06% (p<0.001) faster for Passive versus Control. Passive heat maintenance reduced declines in Tcore that were observed during a simulated half-time period and improved subsequent PPO and repeated sprint ability in professional Rugby Union players.

  4. A Passive Heat Maintenance Strategy Implemented during a Simulated Half-Time Improves Lower Body Power Output and Repeated Sprint Ability in Professional Rugby Union Players

    PubMed Central

    Russell, Mark; West, Daniel J.; Briggs, Marc A.; Bracken, Richard M.; Cook, Christian J.; Giroud, Thibault; Gill, Nicholas; Kilduff, Liam P.

    2015-01-01

    Reduced physical performance has been observed following the half-time period in team sports players, likely due to a decrease in muscle temperature during this period. We examined the effects of a passive heat maintenance strategy employed between successive exercise bouts on core temperature (Tcore) and subsequent exercise performance. Eighteen professional Rugby Union players completed this randomised and counter-balanced study. After a standardised warm-up (WU) and 15 min of rest, players completed a repeated sprint test (RSSA 1) and countermovement jumps (CMJ). Thereafter, in normal training attire (Control) or a survival jacket (Passive), players rested for a further 15 min (simulating a typical half-time) before performing a second RSSA (RSSA 2) and CMJ’s. Measurements of Tcore were taken at baseline, post-WU, pre-RSSA 1, post-RSSA 1 and pre-RSSA 2. Peak power output (PPO) and repeated sprint ability was assessed before and after the simulated half-time. Similar Tcore responses were observed between conditions at baseline (Control: 37.06±0.05°C; Passive: 37.03±0.05°C) and for all other Tcore measurements taken before half-time. After the simulated half-time, the decline in Tcore was lower (-0.74±0.08% vs. -1.54±0.06%, p<0.001) and PPO was higher (5610±105 W vs. 5440±105 W, p<0.001) in the Passive versus Control condition. The decline in PPO over half-time was related to the decline in Tcore (r = 0.632, p = 0.005). In RSSA 2, best, mean and total sprint times were 1.39±0.17% (p<0.001), 0.55±0.06% (p<0.001) and 0.55±0.06% (p<0.001) faster for Passive versus Control. Passive heat maintenance reduced declines in Tcore that were observed during a simulated half-time period and improved subsequent PPO and repeated sprint ability in professional Rugby Union players. PMID:25785393

  5. Geothermal Potential of Ascension Island, South Atlantic.

    DTIC Science & Technology

    1982-11-05

    pyroclastic rocks on Green Mountain are medium-grained syenites which may have formed relatively high-level plutons beneath Green Mountain. In addition, a...dalyite and the petrology of some ejected syenite blocks from Sao Miguel, Azores: Mineral Mag., v. 36, no. 278, p. 227-232. Capuano, R. M., and Bamford

  6. Identifying/Quantifying Environmental Trade-offs Inherent in GHG Reduction Strategies for Coal-Fired Power. Environmental Science and Technology

    EPA Science Inventory

    Improvements to coal power plant technology and the co-fired combustion of biomass promise direct greenhouse gas (GHG) reductions for existing coal-fired power plants. Questions remain as to what the reduction potentials are from a life cycle perspective and if it will result in ...

  7. Identifying/Quantifying Environmental Trade-offs Inherent in GHG Reduction Strategies for Coal-Fired Power. Environmental Science and Technology

    EPA Science Inventory

    Improvements to coal power plant technology and the co-fired combustion of biomass promise direct greenhouse gas (GHG) reductions for existing coal-fired power plants. Questions remain as to what the reduction potentials are from a life cycle perspective and if it will result in ...

  8. Conference Report on the Future of Maritime Strategy (April 1, 1980) and Geopolitics and Maritime Power (September 17-18, 1980),

    DTIC Science & Technology

    1980-01-01

    response will affect greatly the future of American naval power in the r_ gion. Despite the fact that Zimbabwe just emerged from a fif- teen -year civil...opposition of China to this display of naked power and aggression. Continued armed struggle in the Indo-China region and the danger that it may spread create a

  9. 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.

    PubMed

    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. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  10. Enzymatic Fuel Cell-Based Self-Powered Homogeneous Immunosensing Platform via Target-Induced Glucose Release: An Appealing Alternative Strategy for Turn-On Melamine Assay.

    PubMed

    Gu, Chengcheng; Gai, Panpan; Hou, Ting; Li, Haiyin; Xue, Changhui; Li, Feng

    2017-10-04

    Enzymatic fuel cell (EFC)-based self-powered biosensors have attracted considerable attention because of their unique feature of no need for extra power sources during the entire detection process, which endows them with the merits of simplicity, rapidness, low cost, anti-interference, and ease of use. Herein, we proposed, for the first time, an EFC-based self-powered homogeneous immunosensing platform by integrating the target-induced biofuel release and bioconjugate immunoassay for ultrasensitive melamine (ME) detection. In this design, the biofuel, i.e., glucose molecules, was entrapped in the pores of positively charged mesoporous silica nanoparticles and capped by the biogate AuNPs-labeled anti-ME antibody (AuNPs-Ab). The presence of the target ME triggered the entrapped glucose release due to the removal of the biogate via immunoreaction, which resulted in the transfer of electrons produced by glucose oxidation at the bioanode to the biocathode, and thus, the open-circuit voltage of the EFC-based self-powered immunosensor dramatically increased, realizing the ultrasensitive turn-on assay for ME. The limit of detection for ME assay was down to 2.1 pM (S/N = 3), superior to those previously reported in the literature. Notably, real milk samples need no special sample pretreatment for the detection of ME because of the good anti-interference ability of EFC-based self-powered biosensors and the excellent selectivity of the homogeneous immunoassay. Therefore, this appealing self-powered homogeneous immunosensing platform holds great promise as a successful prototype of portable and on-site bioassay in the field of food safety.

  11. Green Power Partnership Program Initiatives

    EPA Pesticide Factsheets

    EPA's Green Power Partnership has a number of initiatives that focus on the collective green power efforts within specific sectors and renewable energy procurement strategies, which provide recognition opportunities for Partners and increase awareness.

  12. An adaptive load-following control system for a space nuclear power system

    NASA Astrophysics Data System (ADS)

    Metzger, John D.; El-Genk, Mohamed S.

    An adaptive load-following control system is proposed for a space nuclear power system. The conceptual design of the SP-100 space nuclear power system proposes operating the nuclear reactor at a base thermal power and accommodating changes in the electrical power demand with a shunt regulator. It is necessary to increase the reactor thermal power if the payload electrical demand exceeds the peak system electrical output for the associated reactor power. When it is necessary to change the nuclear reactor power to meet a change in the power demand, the power ascension or descension must be accomplished in a predetermined manner to avoid thermal stresses in the system and to achieve the desired reactor period. The load-following control system described has the ability to adapt to changes in the system and to changes in the satellite environment. The application is proposed of the model reference adaptive control (MRAC). The adaptive control system has the ability to control the dynamic response of nonlinear systems. Three basic subsets of adaptive control are: (1) gain scheduling, (2) self-tuning regulators, and (3) model reference adaptive control.

  13. PowerSat: A technology demonstration of a solar power satellite

    NASA Technical Reports Server (NTRS)

    Sigler, Douglas L. (Editor); Riedman, John; Duracinski, Jon; Edwards, Joe; Brown, Garry; Webb, Ron; Platzke, Mike; Yuan, Xiaolin; Rogers, Pete; Khan, Afsar

    1994-01-01

    PowerSat is a preliminary design strategy for microwave wireless power transfer of solar energy. Solar power satellites convert solar power into microwave energy and use wireless power transmission to transfer the power to the Earth's surface. The PowerSat project will show how new developments in inflatable technology can be used to deploy solar panels and phased array antennas.

  14. Real-Time Implementation of Type-2 FLC-Based Shunt Active Filter Control Strategies (p-q and Id-Iq) with Different Fuzzy MFs for Power Quality Improvement

    NASA Astrophysics Data System (ADS)

    Mikkili, Suresh; Panda, Anup Kumar

    2014-06-01

    This research article proposes the shunt active filter (SHAF) control strategies (p-q and Id-Iq), which are used to improve the power quality of the electrical network by mitigating the harmonics with the help of Type-2 fuzzy logic controller (Type-2 FLC) different membership functions (MFs). Three-phase reference current waveforms generated by proposed scheme are tracked by the three-phase voltage source converter in a hysteresis band control scheme. The performance of the proposed control strategies has been evaluated in terms of harmonic mitigation and DC link voltage regulation under various source conditions. In order to maintain DC link voltage constant and to generate the compensating reference currents, we have developed Type-2 FLC with different fuzzy MFs (trapezoidal, triangular and Gaussian). The SHAF with proposed Type-2 FLC using Gaussian MF is able to eliminate the uncertainty in the system and SHAF gains outstanding compensation abilities. The detailed real-time results using real-time digital simulator are presented to support the feasibility of proposed control strategies.

  15. Conformal Coating Strategy Comprising N-doped Carbon and Conventional Graphene for Achieving Ultrahigh Power and Cyclability of LiFePO4.

    PubMed

    Zhang, Kan; Lee, Jeong-Taik; Li, Ping; Kang, Byoungwoo; Kim, Jung Hyun; Yi, Gi-Ra; Park, Jong Hyeok

    2015-10-14

    Surface carbon coating to improve the inherent poor electrical conductivity of lithium iron phosphate (LiFePO4, LFP) has been considered as most efficient strategy. Here, we also report one of the conventional methods for LFP but exhibiting a specific capacity beyond the theoretical value, ultrahigh rate performance, and excellent long-term cyclability: the specific capacity is 171.9 mAh/g (70 μm-thick electrode with ∼10 mg/cm(2) loading mass) at 0.1 C (17 mA/g) and retains 143.7 mAh/g at 10 C (1.7 A/g) and 95.8% of initial capacity at 10 C after 1000 cycles. It was found that the interior conformal N-C coating enhances the intrinsic conductivity of LFP nanorods (LFP NR) and the exterior reduced graphene oxide coating acts as an electrically conducting secondary network to electrically connect the entire electrode. The great electron transport mutually promoted with shorten Li diffusion length on (010) facet exposed LFP NR represents the highest specific capacity value recorded to date at 10 C and ultralong-term cyclability. This conformal carbon coating approach can be a promising strategy for the commercialization of LFP cathode in lithium ion batteries.

  16. Re-exploring the high-throughput potential of microextraction techniques, SPME and MEPS, as powerful strategies for medical diagnostic purposes. Innovative approaches, recent applications and future trends.

    PubMed

    Pereira, Jorge; Silva, Catarina Luís; Perestrelo, Rosa; Gonçalves, João; Alves, Vera; Câmara, José S

    2014-03-01

    The human population continues to grow exponentially in the fast developing and most populated countries, whereas in Western Europe it is getting older and older each year. This inevitably raises the demand for better and more efficient medical services without increasing the economic burden in the same proportion. To meet these requirements, improvement of medical diagnosis is certainly a key aspect to consider. Therefore, we need powerful analytical methodologies able to go deeper and further in the characterization of human metabolism and identification of disease biomarkers and endogenous molecules in body fluids and tissues. The ultimate goal is to have a reliable and early medical diagnosis, mitigating the disease complications as much as possible. Microextraction techniques (METs) represent a key step in these analytical methodologies by providing samples in the suitable volumes and purification levels necessary for the characterization of the target analytes. In this aspect, solid-phase microextraction (SPME) and, more recently, microextraction by packed sorbent (MEPS), are powerful sample preparation techniques, characterized by their reduced time of analysis, low solvent consumption, and broad application. Moreover, as miniaturized techniques, they can be easily automatized to have a high-throughput performance in the clinical environment. In this review, we explore some of the most interesting MEPS and SPME applications, focusing on recent trends and applications to medical diagnostic, particularly the in vivo and near real time applications.

  17. Investigation of the Potential for Biofuel Blends in Residual Oil-Fired Power Generation Units as an Emissions Reduction Strategy for New York State

    SciTech Connect

    Krishna, C.R.; McDonald, R.

    2009-05-01

    There is a significant amount of oil, about 12.6 million barrels per year, used for power generation in New York State. The majority of it is residual oil. The primary reason for using residual oil probably is economic, as these fuels are cheaper than distillates. However, the stack emissions from the use of such fuels, especially in densely populated urban areas, can be a cause for concern. The emissions of concern include sulfur and nitrogen oxides and particulates, particularly PM 2.5. Blending with distillate (ASTM No.2) fuels may not reduce some or all of these emissions. Hence, a case can be made for blending with biofuels, such as biodiesel, as they tend to have very little fuel bound sulfur and nitrogen and have been shown in prior work at Brookhaven National Laboratory (BNL) to reduce NOx emissions as well in small boilers. Some of the research carried out at CANMET in Canada has shown potential reductions in PM with blending of biodiesel in distillate oil. There is also the benefit obtaining from the renewable nature of biofuels in reducing the net carbon dioxide emitted thus contributing to the reduction of green house gases that would otherwise be emitted to the atmosphere. The present project was conceived to examine the potential for such benefits of blending biofuels with residual oil. A collaboration was developed with personnel at the New York City Poletti Power Plant of the New York Power Authority. Their interest arose from an 800 MW power plant that was using residual oil and which was mandated to be shut down in 2010 because of environmental concerns. A blend of 20% biodiesel in residual oil had also been tested for a short period of about two days in that boiler a couple of years back. In this project, emission measurements including particulate measurements of PM2.5 were made in the commercial boiler test facility at BNL described below. Baseline tests were done using biodiesel as the blending biofuel. Biodiesel is currently and probably in

  18. Optimal operational strategies for a day-ahead electricity market in the presence of market power using multi-objective evolutionary algorithms

    NASA Astrophysics Data System (ADS)

    Rodrigo, Deepal

    2007-12-01

    This dissertation introduces a novel approach for optimally operating a day-ahead electricity market not only by economically dispatching the generation resources but also by minimizing the influences of market manipulation attempts by the individual generator-owning companies while ensuring that the power system constraints are not violated. Since economic operation of the market conflicts with the individual profit maximization tactics such as market manipulation by generator-owning companies, a methodology that is capable of simultaneously optimizing these two competing objectives has to be selected. Although numerous previous studies have been undertaken on the economic operation of day-ahead markets and other independent studies have been conducted on the mitigation of market power, the operation of a day-ahead electricity market considering these two conflicting objectives simultaneously has not been undertaken previously. These facts provided the incentive and the novelty for this study. A literature survey revealed that many of the traditional solution algorithms convert multi-objective functions into either a single-objective function using weighting schemas or undertake optimization of one function at a time. Hence, these approaches do not truly optimize the multi-objectives concurrently. Due to these inherent deficiencies of the traditional algorithms, the use of alternative non-traditional solution algorithms for such problems has become popular and widely used. Of these, multi-objective evolutionary algorithms (MOEA) have received wide acceptance due to their solution quality and robustness. In the present research, three distinct algorithms were considered: a non-dominated sorting genetic algorithm II (NSGA II), a multi-objective tabu search algorithm (MOTS) and a hybrid of multi-objective tabu search and genetic algorithm (MOTS/GA). The accuracy and quality of the results from these algorithms for applications similar to the problem investigated here

  19. Harnessing the power of the immune system via blockade of PD-1 and PD-L1: a promising new anticancer strategy.

    PubMed

    Reiss, Kim A; Forde, Patrick M; Brahmer, Julie R

    2014-01-01

    Cancer cells employ several mechanisms to evade the immune system of their host, thus escaping immune recognition and elimination. Of particular interest is a cancer cell's ability to co-opt the immune system's innate ligands and inhibitory receptors (also known as checkpoints), thus creating an immunosuppressive microenvironment that downregulates T-cell activation and cell signaling. The recent development of the checkpoint inhibitors anti-programmed death-1 and anti-programmed death ligand-1 has generated an enormous amount of interest as a potential new anticancer strategy in solid tumors, particularly in non-small-cell lung cancer, renal cell carcinoma and melanoma. Data suggest significant disease response rates using anti-programmed death-1 and anti-programmed death ligand-1 antibodies, even in heavily pretreated patients. Future directions include optimization of drug delivery sequence and combination of immunotherapy with other therapies including cytotoxic chemotherapy, radiation, antiangiogenic agents and small-molecule tyrosine kinase inhibitors.

  20. SEE Action Guide for States: Energy Efficiency as a Least-Cost Strategy to Reduce Greenhouse Gases and Air Pollution and Meet Energy Needs in the Power Sector

    SciTech Connect

    Schwartz, Lisa; Leventis, Greg; Schiller, Steven R.; Fadrhonc, Emily Martin; shenot, John; Colburn, Ken; James, Chris; Zetterberg, Johanna; Roy, Molly

    2016-02-01

    This guide is designed to provide information to state decision makers and staff on options to advance energy efficiency through strategies designed or implemented at the state and local levels of government and in the private sector.1 The information in this guide is intended to be useful to a wide variety of partners and stakeholders involved in energy-related discussions and decision-making at state and local levels. These energy efficiency options, or “pathways” as they are identified in this guide, can assist states in using energy efficiency to meet air pollution reduction and other policy objectives such as energy affordability and reliability. A pathway is a set of interdependent actions that results in measurable energy savings streams and associated avoided air emissions and other benefits over a period of time. These activities can include state, local, or private sector regulations, policies, programs and other activities. For each of five broad pathways that offer sizable cost-effective energy savings, the guide addresses likely questions policy makers and regulators face when screening for the best opportunities to advance energy efficiency in their state.

  1. Successful recruitment and retention strategies for a randomized weight management trial for people with diabetes living in rural, medically underserved counties of South Carolina: the POWER study.

    PubMed

    Parra-Medina, Deborah; D'antonio, Angela; Smith, Sharon M; Levin, Sarah; Kirkner, Gregory; Mayer-Davis, Elizabeth

    2004-01-01

    We evaluated the feasibility of recruiting overweight adults with diabetes, living in rural, medically underserved communities, to a weight management intervention consisting of a 12-month clinical trial of two weight management programs and usual care. The sampling frame consisted of adults ages 45 years and older with clinically diagnosed diabetes from two community health centers. The recruitment process included medical record review, prescreening telephone call, two screening visits, and a randomization visit. Over 1,400 medical records were reviewed; 78.6% met eligibility criteria; 60.1% were contacted for telephone prescreening, and 35.5% remained eligible and were interested in participating. Of these, 187 completed visit 1, 164 completed visit 2, and 143 were randomized. Forty-six people were randomized who entered the study as walk-ins at screening visit 1, resulting in 189 subjects. The final yield was 21.5%. Subject mean age was 60.4 years, mean body mass index was 36.4 kg/m(2), 80% were African-American, and 46.6% had less than a high school education. Retention at 12 months was 81.5%. Successful strategies included partnering with community health centers, positive reinforcement and social supportiveness, monitoring progress, and free transportation. This work provides a useful example of an academic-community partnership designed to reach groups previously considered hard to reach.

  2. Soil sampling and analytical strategies for mapping fallout in nuclear emergencies based on the Fukushima Dai-ichi Nuclear Power Plant accident.

    PubMed

    Onda, Yuichi; Kato, Hiroaki; Hoshi, Masaharu; Takahashi, Yoshio; Nguyen, Minh-Long

    2015-01-01

    The Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident resulted in extensive radioactive contamination of the environment via deposited radionuclides such as radiocesium and (131)I. Evaluating the extent and level of environmental contamination is critical to protecting citizens in affected areas and to planning decontamination efforts. However, a standardized soil sampling protocol is needed in such emergencies to facilitate the collection of large, tractable samples for measuring gamma-emitting radionuclides. In this study, we developed an emergency soil sampling protocol based on preliminary sampling from the FDNPP accident-affected area. We also present the results of a preliminary experiment aimed to evaluate the influence of various procedures (e.g., mixing, number of samples) on measured radioactivity. Results show that sample mixing strongly affects measured radioactivity in soil samples. Furthermore, for homogenization, shaking the plastic sample container at least 150 times or disaggregating soil by hand-rolling in a disposable plastic bag is required. Finally, we determined that five soil samples within a 3 m × 3-m area are the minimum number required for reducing measurement uncertainty in the emergency soil sampling protocol proposed here.

  3. Choosing the optimal therapeutic strategy for placental polyps using power Doppler color scoring: Transarterial embolization followed by hysteroscopic resection or expectant management?

    PubMed

    Mori, Masahiko; Iwase, Akira; Osuka, Satoko; Kondo, Mika; Nakamura, Tomoko; Nakahara, Tatsuo; Goto, Maki; Kikkawa, Fumitaka

    2016-08-01

    To evaluate a protocol for selection of placental polyp management, including expectant management and hysteroscopic resection with or without transarterial embolization (TAE), using power Doppler color score (PDCS) as the vascularity parameter. This retrospective case-control study included 25 patients who were diagnosed with placental polyps. We evaluated the vascularity of placental polyps with PDCS measured by transvaginal ultrasonography as follows: PDCS 1, no blood flow; PDCS 2, minimal flow; PDCS 3, moderate flow; and PDCS 4, marked blood flow. We then selected expectant management or hysteroscopic resection with or without TAE. Three of 17 patients with PDCS 1 or 2 underwent surgical intervention, and expectant management was successful in 14. Seven of eight patients with PDCS 3 or 4 underwent surgical intervention, while expectant management was successful in only one patient. PDCS is a simple examination for evaluating the vascularity of placental polyps. PDCS might be useful for selecting the optimal treatment for placental polyps, such as expectant management or surgical intervention, according to their vascularity. Copyright © 2016. Published by Elsevier B.V.

  4. Dissociation of pentameric to monomeric C-reactive protein localizes and aggravates inflammation: in vivo proof of a powerful proinflammatory mechanism and a new anti-inflammatory strategy.

    PubMed

    Thiele, Jan R; Habersberger, Jonathon; Braig, David; Schmidt, Yvonne; Goerendt, Kurt; Maurer, Valentin; Bannasch, Holger; Scheichl, Amelie; Woollard, Kevin J; von Dobschütz, Ernst; Kolodgie, Frank; Virmani, Renu; Stark, G Bjoern; Peter, Karlheinz; Eisenhardt, Steffen U

    2014-07-01

    The relevance of the dissociation of circulating pentameric C-reactive protein (pCRP) to its monomeric subunits (mCRP) is poorly understood. We investigated the role of conformational C-reactive protein changes in vivo. We identified mCRP in inflamed human striated muscle, human atherosclerotic plaque, and infarcted myocardium (rat and human) and its colocalization with inflammatory cells, which suggests a general causal role of mCRP in inflammation. This was confirmed in rat intravital microscopy of lipopolysaccharide-induced cremasteric muscle inflammation. Intravenous pCRP administration significantly enhanced leukocyte rolling, adhesion, and transmigration via localized dissociation to mCRP in inflamed but not noninflamed cremaster muscle. This was confirmed in a rat model of myocardial infarction. Mechanistically, this process was dependent on exposure of lysophosphatidylcholine on activated cell membranes, which is generated after phospholipase A2 activation. These membrane changes could be visualized intravitally on endothelial cells, as could the colocalized mCRP generation. Blocking of phospholipase A2 abrogated C-reactive protein dissociation and thereby blunted the proinflammatory effects of C-reactive protein. Identifying the dissociation process as a therapeutic target, we stabilized pCRP using 1,6-bis(phosphocholine)-hexane, which prevented dissociation in vitro and in vivo and consequently inhibited the generation and proinflammatory activity of mCRP; notably, it also inhibited mCRP deposition and inflammation in rat myocardial infarction. These results provide in vivo evidence for a novel mechanism that localizes and aggravates inflammation via phospholipase A2-dependent dissociation of circulating pCRP to mCRP. mCRP is proposed as a pathogenic factor in atherosclerosis and myocardial infarction. Most importantly, the inhibition of pCRP dissociation represents a promising, novel anti-inflammatory therapeutic strategy. © 2014 American Heart

  5. In-vessel Retention Strategy for High Power Reactors - K-INERI Final Report (includes SBLB Test Results for Task 3 on External Reactor Vessel Cooling (ERVC) Boiling Data and CHF Enhancement Correlations)

    SciTech Connect

    F. B. Cheung; J. Yang; M. B. Dizon; J. Rempe

    2005-01-01

    In-vessel retention (IVR) of core melt is a key severe accident management strategy adopted by some operating nuclear power plants and proposed for some advanced light water reactors (ALWRs). If there were inadequate cooling during a reactor accident, a significant amount of core material could become molten and relocate to the lower head of the reactor vessel, as happened in the Three Mile Island Unit 2 (TMI-2) accident. If it is possible to ensure that the vessel head remains intact so that relocated core materials are retained within the vessel, the enhanced safety associated with these plants can reduce concerns about containment failure and associated risk. For example, the enhanced safety of the Westinghouse Advanced 600 MWe PWR (AP600), which relied upon External Reactor Vessel Cooling (ERVC) for IVR, resulted in the U.S. Nuclear Regulatory Commission (US NRC) approving the design without requiring certain conventional features common to existing LWRs. However, it is not clear that currently proposed external reactor vessel cooling (ERVC) without additional enhancements could provide sufficient heat removal for higher-power reactors (up to 1500 MWe). Hence, a collaborative, three-year, U.S. - Korean International Nuclear Energy Research Initiative (INERI) project was completed in which the Idaho National Engineering and Environmental Laboratory (INEEL), Seoul National University (SNU), Pennsylvania State University (PSU), and the Korea Atomic Energy Research Institute (KAERI) investigated the performance of ERVC and an in-vessel core catcher (IVCC) to determine if IVR is feasible for reactors up to 1500 MWe.

  6. Overview paper on nuclear power

    SciTech Connect

    Spiewak, I.; Cope, D.F.

    1980-09-01

    This paper was prepared as an input to ORNL's Strategic Planning Activity, ORNL National Energy Perspective (ONEP). It is intended to provide historical background on nuclear power, an analysis of the mission of nuclear power, a discussion of the issues, the technology choices, and the suggestion of a strategy for encouraging further growth of nuclear power.

  7. Space station power management and distribution

    NASA Technical Reports Server (NTRS)

    Teren, F.

    1985-01-01

    The power system architecture is presented by a series of schematics which illustrate the power management and distribution (PMAD) system at the component level, including converters, controllers, switchgear, rotary power transfer devices, power and data cables, remote power controllers, and load converters. Power distribution options, reference power management, and control strategy are also outlined. A summary of advanced development status and plans and an overview of system test plans are presented.

  8. Ephemeris Generation for ETS-VI and Its Effects on Pointing Strategies Adopted for Daytime Acquisition and Tracking

    NASA Astrophysics Data System (ADS)

    Owen, W. M., Jr.; Gillam, S. D.; Young, J. W.; Mayes, D. L.

    1996-10-01

    Critical to the success of the Ground/Orbiter Lasercomm Demonstration (GOLD) was the ability of the two telescopes at the Table Mountain Facility (TMF) to track the Japanese Engineering Test Satellite (ETS-VI). This article describes the process of generating pointing predictions from the satellite's orbital elements, experiments to determine the inherent pointing accuracy of the TMF telescopes, and the strategies developed for overcoming errors in the satellite's ephemeris. The combination of ephemeris precision, telescope-pointing precision, and low satellite contrast against the bright sky made daytime satellite acquisition a serious challenge. Inherent telescope-pointing error in right ascension, end play in the declination axis worm gear, and pointing error induced by the statistical errors in the ephemeris were thought to be the main sources of error in the telescope pointing.

  9. An optimal tuning strategy for tidal turbines

    NASA Astrophysics Data System (ADS)

    Vennell, Ross

    2016-11-01

    Tuning wind and tidal turbines is critical to maximizing their power output. Adopting a wind turbine tuning strategy of maximizing the output at any given time is shown to be an extremely poor strategy for large arrays of tidal turbines in channels. This `impatient-tuning strategy' results in far lower power output, much higher structural loads and greater environmental impacts due to flow reduction than an existing `patient-tuning strategy' which maximizes the power output averaged over the tidal cycle. This paper presents a `smart patient tuning strategy', which can increase array output by up to 35% over the existing strategy. This smart strategy forgoes some power generation early in the half tidal cycle in order to allow stronger flows to develop later in the cycle. It extracts enough power from these stronger flows to produce more power from the cycle as a whole than the existing strategy. Surprisingly, the smart strategy can often extract more power without increasing maximum structural loads on the turbines, while also maintaining stronger flows along the channel. This paper also shows that, counterintuitively, for some tuning strategies imposing a cap on turbine power output to limit loads can increase a turbine's average power output.

  10. An optimal tuning strategy for tidal turbines.

    PubMed

    Vennell, Ross

    2016-11-01

    Tuning wind and tidal turbines is critical to maximizing their power output. Adopting a wind turbine tuning strategy of maximizing the output at any given time is shown to be an extremely poor strategy for large arrays of tidal turbines in channels. This 'impatient-tuning strategy' results in far lower power output, much higher structural loads and greater environmental impacts due to flow reduction than an existing 'patient-tuning strategy' which maximizes the power output averaged over the tidal cycle. This paper presents a 'smart patient tuning strategy', which can increase array output by up to 35% over the existing strategy. This smart strategy forgoes some power generation early in the half tidal cycle in order to allow stronger flows to develop later in the cycle. It extracts enough power from these stronger flows to produce more power from the cycle as a whole than the existing strategy. Surprisingly, the smart strategy can often extract more power without increasing maximum structural loads on the turbines, while also maintaining stronger flows along the channel. This paper also shows that, counterintuitively, for some tuning strategies imposing a cap on turbine power output to limit loads can increase a turbine's average power output.

  11. Operating strategy generators for nuclear reactors

    SciTech Connect

    Solovyev, D. A. Semenov, A. A.; Shchukin, N. V.

    2011-12-15

    Operating strategy generators, i.e., the software intended for increasing the efficiency of work of nuclear power plant operators, are discussed. The possibilities provided by the domestic and foreign operating-strategy generators are analyzed.

  12. History Alive! Six Powerful Constructivist Strategies.

    ERIC Educational Resources Information Center

    Bower, Bert; Lobdell, Jim

    1998-01-01

    Describes six activities from the "History Alive" program. These include an interactive slide lecture on the Great Depression, a photographic analysis regarding Mexican and Southwest culture, an experiential exercise concerning life on the assembly line, collages on Chinese belief systems, a response group on women's rights, and poetry writing.…

  13. History Alive! Six Powerful Constructivist Strategies.

    ERIC Educational Resources Information Center

    Bower, Bert; Lobdell, Jim

    1998-01-01

    Describes six activities from the "History Alive" program. These include an interactive slide lecture on the Great Depression, a photographic analysis regarding Mexican and Southwest culture, an experiential exercise concerning life on the assembly line, collages on Chinese belief systems, a response group on women's rights, and poetry writing.…

  14. Teaching power concepts.

    PubMed

    Heineken, J; McCloskey, J C

    1985-01-01

    Concepts and strategies presented here provide nurses with a new perspective from which to analyze and interact with power dynamics. Understanding fundamental concepts of power will help nurses enjoy a more equal status and bargaining position within the community of health professionals and in health care delivery systems. As nurses integrate and utilize this content for enhancing professional practices and client services, our public image will also continue to be strengthened. In so doing, our power base and sphere of influence will also be broadened.

  15. Tree Growth and Climate Relationship: Dynamics of Scots Pine (Pinus Sylvestris L.) Growing in the Near-Source Region of the Combined Heat and Power Plant During the Development of the Pro-Ecological Strategy in Poland.

    PubMed

    Sensuła, Barbara; Wilczyński, Sławomir; Opała, Magdalena

    Since the 1990s, the emission of pollutants was reduced in a majority of Polish and developing country factories whereas the level of energy production was similar to that prior to the 1990s. The conifer investigated in this study has grown for many years under the stress of industrial pollution. Despite this, the trees are preserved, to a large extent, sensitive to the natural climatic factors. We present a complex analysis of the climatic (sunshine, temperature, precipitation, humidity, and wind circulation) and anthropogenic factors influencing the radial increment dynamics of Scots pine (Pinus sylvestris L.) growing in the vicinity of the combined heat and power station in Łaziska (Poland). We analyzed the spatiotemporal distribution of growth reductions, the depth of reduction with respect to the distance from the emitter, the relationship between tree growth and climate during the industry development period and during proecological strategy application . Samples of carbon isotopic composition in pine needles from 2012 to 2013 were additionally determined. Pines series of 3 positions indicate that they have a similar sensitivity to most climatic elements of the previous and given year, but there is also a different rhythm between the studied populations of incremental growth of pines. The causes of diversity are due to the different types of habitat (site types) and industrial pollution. The variation in carbon stable isotopic composition in pine needles was connected with an increase of CO2.

  16. Competitive power development

    SciTech Connect

    Garrity, T.F.; Stoll, H.G.

    1994-12-31

    Electric power is essential to economic growth and the improvement in the standard of living in modern societies. Maximizing the overall economic efficiency of electric power production can lead to even stronger economic growth. Overall electricity efficiency can be driven by utilization of the newest and most economically efficient technologies, utilization of the most efficient financial structuring, and efficient integration of coproduction of electricity and process energy. The challenge is to drive the power generation strategy toward maximum economic efficiency while improving the overall country environment emissions. This paper reviews the key power generation technologies available today and in the near future. Of key importance is the capital cost, efficiency, environmental impacts, and reliability of each technology and how these technologies can be integrated with efficient financial structurings to maximize the country power generation economic efficiency. Examples of several countries are used to show recent successes in maximizing economic efficiency.

  17. The Unseen Power Loss: Stemming the Flow.

    ERIC Educational Resources Information Center

    Gillett, Raphael

    2002-01-01

    Outlined an estimate-substitution strategy for a test comparing two means and developed an expected-power formula for the test. Demonstrated that for empirically representative distributions of effect size in psychology, the expected power deficit is large. (SLD)

  18. High Power Cryogenic Targets

    SciTech Connect

    Gregory Smith

    2011-08-01

    The development of high power cryogenic targets for use in parity violating electron scattering has been a crucial ingredient in the success of those experiments. As we chase the precision frontier, the demands and requirements for these targets have grown accordingly. We discuss the state of the art, and describe recent developments and strategies in the design of the next generation of these targets.

  19. Solid-State Nuclear Power

    NASA Technical Reports Server (NTRS)

    George, Jeffrey A.

    2012-01-01

    A strategy for "Solid-State" Nuclear Power is proposed to guide development of technologies and systems into the second 50 years of nuclear spaceflight. The strategy emphasizes a simple and highly integrated system architecture with few moving parts or fluid loops; the leverage of modern advances in materials, manufacturing, semiconductors, microelectromechanical and nanotechnology devices; and the targeted advancement of high temperature nuclear fuels, materials and static power conversion to enable high performance from simple system topologies.

  20. Leadership Strategies for Managing Conflict.

    ERIC Educational Resources Information Center

    Kormanski, Chuck

    1982-01-01

    Discusses the impact of conflict in small group development theory. Views conflict as a positive, normally occurring behavior and presents leadership strategies involving withdrawal, suppression, integration, compromise, and power. Examines situational contingencies and presents a rationale for strategy selection and intervention. (Author)

  1. Distributed Space Solar Power

    NASA Technical Reports Server (NTRS)

    Fork, Richard L.

    2001-01-01

    The objective was to assess the feasibility of safely collecting solar power at geostationary orbit and delivering it to earth. A strategy which could harness a small fraction of the millions of gigawatts of sunlight passing near earth could adequately supply the power needs of earth and those of space exploration far into the future. Light collected and enhanced both spatially and temporally in space and beamed to earth provides probably the only practical means of safe and efficient delivery of this space solar power to earth. In particular, we analyzed the feasibility of delivering power to sites on earth at a comparable intensity, after conversion to a usable form, to existing power needs. Two major obstacles in the delivery of space solar power to earth are safety and the development of a source suitable for space. We focused our approach on: (1) identifying system requirements and designing a strategy satisfying current eye and skin safety requirements; and (2) identifying a concept for a potential space-based source for producing the enhanced light.

  2. Power systems for future missions

    NASA Technical Reports Server (NTRS)

    Gill, S. P.; Frye, P. E.; Littman, Franklin D.; Meisl, C. J.

    1994-01-01

    A comprehensive scenario of future missions was developed and applicability of different power technologies to these missions was assessed. Detailed technology development roadmaps for selected power technologies were generated. A simple methodology to evaluate economic benefits of current and future power system technologies by comparing Life Cycle Costs of potential missions was developed. The methodology was demonstrated by comparing Life Cycle Costs for different implementation strategies of DIPS/CBC technology to a selected set of missions.

  3. Patient Power!

    MedlinePlus

    ... turn JavaScript on. Feature: Crowdsourcing & Rare Diseases Patient Power! Past Issues / Winter 2016 Table of Contents Social ... Porzecanski couldn't be happier that such "patient power" efforts will help SCLS patients who otherwise would ...

  4. Power Play.

    ERIC Educational Resources Information Center

    Aho, Timothy A.

    1998-01-01

    Describes how to integrate technology into old buildings beginning with an evaluation of the electric power systems. A case study is highlighted showing the process in determining existing conditions, assessing electric power needs, and designing upgrades. (GR)

  5. Pulsed power

    NASA Astrophysics Data System (ADS)

    Stone, David H.

    Pulsed power systems are critical elements for such prospective weapons technologies as high-power microwaves, electrothermal and electromagnetic projectile launchers, neutral particle beams, space-based FELs, ground-based lasers, and charged particle beams. Pulsed power will also be essential for the development of nonweapon military systems such as lidars and ultrawideband radars, and could serve as the bases for nuclear weapon effect simulators. The pulsed power generation requirements for each of these systems is considered.

  6. Power processing

    NASA Technical Reports Server (NTRS)

    Schwarz, F. C.

    1971-01-01

    Processing of electric power has been presented as a discipline that draws on almost every field of electrical engineering, including system and control theory, communications theory, electronic network design, and power component technology. The cost of power processing equipment, which often equals that of expensive, sophisticated, and unconventional sources of electrical energy, such as solar batteries, is a significant consideration in the choice of electric power systems.

  7. A new clustering strategy

    NASA Astrophysics Data System (ADS)

    Feng, Jian-xin; Tang, Jia-fu; Wang, Guang-xing

    2007-04-01

    On the basis of the analysis of clustering algorithm that had been proposed for MANET, a novel clustering strategy was proposed in this paper. With the trust defined by statistical hypothesis in probability theory and the cluster head selected by node trust and node mobility, this strategy can realize the function of the malicious nodes detection which was neglected by other clustering algorithms and overcome the deficiency of being incapable of implementing the relative mobility metric of corresponding nodes in the MOBIC algorithm caused by the fact that the receiving power of two consecutive HELLO packet cannot be measured. It's an effective solution to cluster MANET securely.

  8. Space Power

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Appropriate directions for the applied research and technology programs that will develop space power systems for U.S. future space missions beyond 1995 are explored. Spacecraft power supplies; space stations, space power reactors, solar arrays, thermoelectric generators, energy storage, and communication satellites are among the topics discussed.

  9. Power supply

    DOEpatents

    Yakymyshyn, Christopher Paul; Hamilton, Pamela Jane; Brubaker, Michael Allen

    2007-12-04

    A modular, low weight impedance dropping power supply with battery backup is disclosed that can be connected to a high voltage AC source and provide electrical power at a lower voltage. The design can be scaled over a wide range of input voltages and over a wide range of output voltages and delivered power.

  10. Power-constrained supercomputing

    NASA Astrophysics Data System (ADS)

    Bailey, Peter E.

    . Adaptive power balancing efficiently predicts where critical paths are likely to occur and distributes power to those paths. Greater power, in turn, allows increased thread concurrency levels, CPU frequency/voltage, or both. We describe these techniques in detail and show that, compared to the state-of-the-art technique of using statically predetermined, per-node power caps, Conductor leads to a best-case performance improvement of up to 30%, and an average improvement of 19.1%. At the node level, an accurate power/performance model will aid in selecting the right configuration from a large set of available configurations. We present a novel approach to generate such a model offline using kernel clustering and multivariate linear regression. Our model requires only two iterations to select a configuration, which provides a significant advantage over exhaustive search-based strategies. We apply our model to predict power and performance for different applications using arbitrary configurations, and show that our model, when used with hardware frequency-limiting in a runtime system, selects configurations with significantly higher performance at a given power limit than those chosen by frequency-limiting alone. When applied to a set of 36 computational kernels from a range of applications, our model accurately predicts power and performance; our runtime system based on the model maintains 91% of optimal performance while meeting power constraints 88% of the time. When the runtime system violates a power constraint, it exceeds the constraint by only 6% in the average case, while simultaneously achieving 54% more performance than an oracle. Through the combination of the above contributions, we hope to provide guidance and inspiration to research practitioners working on runtime systems for power-constrained environments. We also hope this dissertation will draw attention to the need for software and runtime-controlled power management under power constraints at various levels

  11. Appropriate strategies.

    PubMed

    Halty, M

    1979-01-01

    Technology strategies are concerned with the production, distribution, and consumption of technology. Observation of less developed countries (LDCs) and international organizations shows that little attention is given to the development of a technology strategy. LDCs need to formulate a strategy of self-reliant technological development for the next decade. They should no longer be content to stand in a technologically dependent relationship to the developed countries. Such strategies must balance the ratio between investment in indigenous technologies and expenditure for foreign technology. The strategies change according to the level of industrialization achieved. The following considerations come into development of technology strategies: 1) determination of an appropriate balance among the accumulation, consumption, and distribution of technology; 2) the amount and level of government support; and 3) the balance between depth and breadth of technology to be encouraged.

  12. Study on Dynamic Voltage Restorer Compensation Strategy

    NASA Astrophysics Data System (ADS)

    Li, Yanpeng; Wang, Tianzheng; Bai, Lu; Lu, zhumao; Ma, Liqiang

    2017-05-01

    In the research data about power quality, it is shown that voltage sag is the worst power quality problem, which can bring the most losses in various power quality problems. Dynamic voltage restorer (DVR) is the most effective solution to suppress the voltage sag. The compensation effect of DVR can be affected by the compensation strategy. Based on the analysis of existing compensation strategy, the optimized compensation strategy of load voltage is proposed in this paper. The simulation results show that the optimized compensation strategy can give attention to both the capacity of DVR and the compensation effect of the load side voltage.

  13. SATCOM constellation power simulation

    SciTech Connect

    Capulli, J.; Badke, B.; Davis, G.

    1995-12-31

    Three basic variables directly impact the power and energy generated by the SATCOM satellite constellation and its individual Space Vehicles (SVs). They are (1) telecommunications traffic patterns, (2) network resource management controllables, and (3) system hardware and software performance. This power simulation has verified the robustness of the telecommunications architecture. It has validated the onboard resource allocation process from an SV and network level power and energy perspective. The analyses have led to development of operational procedures that prevent SV node outages, and maximize network telecommunication traffic capacity. The program objective is to optimize overall system operation, availability and quality of service. Achieving this goal requires a thorough understanding of the Electrical Power Subsystem and its interfaces. The EPS simulation model analyzes network level performance by evaluating requirement compliance in the expected operating environments. Specifically, the simulation tool evaluates different design approaches and network operational strategies from a power and energy perspective. As a result, optimal load management solutions will be implemented both on-board the SV and via ground station directed resource allocation strategies.

  14. A belief-based evolutionarily stable strategy.

    PubMed

    Deng, Xinyang; Wang, Zhen; Liu, Qi; Deng, Yong; Mahadevan, Sankaran

    2014-11-21

    As an equilibrium refinement of the Nash equilibrium, evolutionarily stable strategy (ESS) is a key concept in evolutionary game theory and has attracted growing interest. An ESS can be either a pure strategy or a mixed strategy. Even though the randomness is allowed in mixed strategy, the selection probability of pure strategy in a mixed strategy may fluctuate due to the impact of many factors. The fluctuation can lead to more uncertainty. In this paper, such uncertainty involved in mixed strategy has been further taken into consideration: a belief strategy is proposed in terms of Dempster-Shafer evidence theory. Furthermore, based on the proposed belief strategy, a belief-based ESS has been developed. The belief strategy and belief-based ESS can reduce to the mixed strategy and mixed ESS, which provide more realistic and powerful tools to describe interactions among agents. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Electric power

    SciTech Connect

    Chase, M.

    1988-01-01

    This text examines the critical problems faced by the electric power industry, shown in the context of a detailed description of the history and development of the industry. A new industry initiative is proposed that will allow for a more effective response to industry fluctuations. Topics covered include developments in power technology federal nuclear power regulation and legislation, environmentalism and conservationism, industry financial problems, capital minimization, and responses to utility responsibility.

  16. Methods and Strategies: Talk Strategies

    ERIC Educational Resources Information Center

    Shea, Lauren M.; Shanahan, Therese B.

    2011-01-01

    This article discusses how to promote oral language development through science. The authors describe how they incorporate academic "talk strategies" into science lessons in a nonintrusive and meaningful manner. These talk strategies are adapted from the "Avenues" (2007) curriculum for English learners (ELs), which gives examples of cooperative…

  17. Power Tactics.

    ERIC Educational Resources Information Center

    Freeman, Laurie

    1996-01-01

    Boulder Valley (Colorado) finds savings with an energy-management strategy that makes conservation automatic. Phase-one strategies included a complete lighting system upgrade and a computerized climate-control system. The energy program has helped the district cut monthly kilowatt consumption by 42%, and natural gas consumption has dropped 27%.…

  18. Fuel cells for distributed power generation

    NASA Astrophysics Data System (ADS)

    Tarman, Paul B.

    Deregulation has caused a major change in power distribution in the USA. Large central power stations are being and will continue to be replaced by smaller, distributed power generation sources of less than 20 kW. Fuel cells, specifically molten carbonate fuel cells (MCFCs), are best suited to serve this need. Small turbines cannot achieve the efficiency or environmental friendliness of MCFCs in this power range. This paper discusses the goals of M-C Power Corporation and the advantages of its IMHEX® MCFC technology. M-C Power's factory, demonstration testing program, and its market-entry power plant are also described, as are its commercialization strategy and schedule.

  19. Powerful Literacies.

    ERIC Educational Resources Information Center

    Crowther, Jim, Ed.; Hamilton, Mary, Ed.; Tett, Lyn, Ed.

    These 15 papers share a common theme: seeking to promote literacy as a powerful tool for challenging existing inequalities and dependencies. "Powerful Literacies" (Jim Crowther et al.) is an introduction. Section 1 establishes the theoretical and policy frameworks that underpin the book and shows how literacy is situated in different…

  20. Powerful Literacies.

    ERIC Educational Resources Information Center

    Crowther, Jim, Ed.; Hamilton, Mary, Ed.; Tett, Lyn, Ed.

    These 15 papers share a common theme: seeking to promote literacy as a powerful tool for challenging existing inequalities and dependencies. "Powerful Literacies" (Jim Crowther et al.) is an introduction. Section 1 establishes the theoretical and policy frameworks that underpin the book and shows how literacy is situated in different…

  1. Diastatic power

    USDA-ARS?s Scientific Manuscript database

    diastatic power: Diastatic power, abbreviated DP, is the total activity of malt starch degrading enzymes that hydrolyze starch to fermentable sugars. The starch degrading enzymes contributing to this process are a-amylase, ß-amylase, limit dextrinase, and a-glucosidase. The driving force for DP a...

  2. Power Source

    ERIC Educational Resources Information Center

    Schooley, Michael L.

    2010-01-01

    Principals are powerful: They are the primary catalysts for creating a lasting foundation for learning, driving school and student performance, and shaping the long-term impact of school improvement efforts. Yet few principals would characterize themselves as powerful. Rather, they're self-effacing, adaptable, pragmatic, and quick to share credit…

  3. Cetacean Strategies.

    ERIC Educational Resources Information Center

    Gilliland, Denise DelGrosso

    1991-01-01

    Suggested are activities about whales for children in schools not near the ocean. Activities designed to pique students' interest in whales and to investigate the size, breathing, buoyancy, and feeding strategies of whales are discussed. (CW)

  4. Hiring Strategies.

    ERIC Educational Resources Information Center

    Bugliani, Ann

    1994-01-01

    A discussion of hiring strategies in a university foreign language department includes the following: the preconvention (Modern Language Association) process; convention interviews; campus visits; final selections; and hiring foreign nationals. (Contains two references.) (LB)

  5. Cetacean Strategies.

    ERIC Educational Resources Information Center

    Gilliland, Denise DelGrosso

    1991-01-01

    Suggested are activities about whales for children in schools not near the ocean. Activities designed to pique students' interest in whales and to investigate the size, breathing, buoyancy, and feeding strategies of whales are discussed. (CW)

  6. Power systems

    NASA Astrophysics Data System (ADS)

    Kaplan, G.

    1982-01-01

    Significant events in current, prototype, and experimental utility power generating systems in 1981 are reviewed. The acceleration of licensing and the renewal of plans for reprocessing of fuel for nuclear power plants are discussed, including the rise of French reactor-produced electricity to over 40% of the country's electrical output. A 4.5 MW fuel cell neared completion in New York City, while three 2.5 MW NASA-designed windpowered generators began producing power in the state of Washington. Static bar compensators, nonflammable-liquid cooled power transformers, and ZnO surge arrestors were used by utilities for the first time, and the integration of a coal gasifier-combined cycle power plant approached the planning phase. An MHD generator was run for 1000 hours and produced 50-60 kWe, while a 20 MVA superconducting generator was readied for testing.

  7. Power system

    DOEpatents

    Hickam, Christopher Dale

    2008-03-18

    A power system includes a prime mover, a transmission, and a fluid coupler having a selectively engageable lockup clutch. The fluid coupler may be drivingly connected between the prime mover and the transmission. Additionally, the power system may include a motor/generator drivingly connected to at least one of the prime mover and the transmission. The power-system may also include power-system controls configured to execute a control method. The control method may include selecting one of a plurality of modes of operation of the power system. Additionally, the control method may include controlling the operating state of the lockup clutch dependent upon the mode of operation selected. The control method may also include controlling the operating state of the motor/generator dependent upon the mode of operation selected.

  8. New strategies in O M

    SciTech Connect

    Seeley, R.S.

    1993-10-01

    Companies that provide operations and maintenance (O M) services to independent power plants are changing their strategies in response to increasing cost pressures on owners. O M contractors are fine-tuning their approaches in several ways. Global contracts, new controls, and computerization are some of their strategies they are using. With these new approaches O M contractors can improve their services and project owners bottom lines.

  9. Egypt- Old Ally, New Strategy

    DTIC Science & Technology

    2017-04-06

    history , then discussion on traditional soft and hard power, then introduce the concept of smart power. Next, this essay will provide a description...Finally, this essay will summarize the recommendations in one holistic strategy. Brief Sinai History It is important to understand, at least at...the cursory level, the modern struggle for control of the Sinai. In recent modern history the area was torn by war between Egypt and Israel

  10. The NASA Meter Class Autonomous Telescope: Ascension Island

    DTIC Science & Technology

    2013-09-01

    gigabytes of image data nightly. With fainter detection limits, precision detection, acquisition and tracking of targets, multi-color photometry ...image data nightly. With fainter detection limits, precision detection, acquisition and tracking of targets, multi-color photometry , precision astrometry...expected to increase both extinction and scattering of moonlight. This is hard to quantify without photometry , but could be substantial. Sea salt aerosols

  11. Power performance

    SciTech Connect

    Anderson, J.

    1996-04-01

    Two power generation engineering and construction firms with international markets are briefly described in this article. Bibb and Associates and Black & Veatch, both Kansas-based companies, are discussed. Current projects and services provided by the companies are described.

  12. Fusion Power.

    ERIC Educational Resources Information Center

    Dingee, David A.

    1979-01-01

    Discusses the extraordinary potential, the technical difficulties, and the financial problems that are associated with research and development of fusion power plants as a major source of energy. (GA)

  13. Fusion Power.

    ERIC Educational Resources Information Center

    Dingee, David A.

    1979-01-01

    Discusses the extraordinary potential, the technical difficulties, and the financial problems that are associated with research and development of fusion power plants as a major source of energy. (GA)

  14. Metacognitive Strategies.

    PubMed

    Schiff, Rachel; Nuri Ben-Shushan, Yohi; Ben-Artzi, Elisheva

    This study assessed the effect of metacognitive instruction on the spelling and word reading of Hebrew-speaking children with specific language impairment (SLI). Participants were 67 kindergarteners with SLI in a supported learning context. Children were classified into three spelling instruction groups: (a) metalinguistic instruction (ML), (b) ML that integrates metacognitive strategies (MCML), and (c) a control group. Letter naming, letter sounding, word spelling, and word recognition were assessed at pretest and posttest. Findings from spelling and reading tests as well as interviews indicated that both the ML and MCML groups made statistically significant gains in all measures, whereas the control group did not. However, children with SLI who received training in metacognitive strategies significantly outperformed those who received ML alone in spelling and reading skills. This study provides evidence that children with SLI benefit from applying of metacognitive strategies to spelling practices when acquiring early spelling and reading skills.

  15. Power combiner

    DOEpatents

    Arnold, Mobius; Ives, Robert Lawrence

    2006-09-05

    A power combiner for the combining of symmetric and asymmetric traveling wave energy comprises a feed waveguide having an input port and a launching port, a reflector for reflecting launched wave energy, and a final waveguide for the collection and transport of launched wave energy. The power combiner has a launching port for symmetrical waves which comprises a cylindrical section coaxial to the feed waveguide, and a launching port for asymmetric waves which comprises a sawtooth rotated about a central axis.

  16. Power Supply

    NASA Astrophysics Data System (ADS)

    1991-01-01

    Maxwell Laboratories capacitor charging power supply is the first commercial spinoff from the NASA CCDS program - a consortia of industries and government establishments to accelerate development of ground and space based commercial applications of NASA technology. The power supply transforms and conditions large voltages to charge capacitors used in x-ray sources, medical accelerators, etc. It is lighter, more reliable, more compact and efficient. Originally developed for space lasers, its commercial potential was soon recognized.

  17. Study on synergetic schedule of hydro-wind power for minimizing impact on power grid

    NASA Astrophysics Data System (ADS)

    Zhu, Weijiang; Hu, Binqi; Cheng, Tao; Liu, Jianping; Wu, Yonggang; Yu, Yi

    2017-08-01

    For smoothing and weakening the random and fluctuant wind power, an approach of hydropower coordinate with wind power is proposed. Firstly, based on a certain capacity of wind farm and the hypothesis of indifference of wind power capacity in this paper, the capacity of hydropower station to absorb wind power has been analyzed quantitatively and the relationship characteristic curve between hydropower and wind power absorption has been depicted; secondly, the characteristic of the curve under the condition of different quantities of wind power electricity is analyzed and proved; finally, a model which maximizes the combination of hydro-wind power is built and an adjustable hydropower plant coordinated with wind power station is simulated. According to the results, the effect of wind power absorption was fairly good and the output of combo that hydropower cooperated with wind power was stable, and this research has provided a favorable strategy for absorbing wind power for power grid.

  18. Optimal Power Flow Pursuit

    SciTech Connect

    Dall'Anese, Emiliano

    2016-08-01

    Past works that focused on addressing power-quality and reliability concerns related to renewable energy resources (RESs) operating with business-as-usual practices have looked at the design of Volt/VAr and Volt/Watt strategies to regulate real or reactive powers based on local voltage measurements, so that terminal voltages are within acceptable levels. These control strategies have the potential of operating at the same time scale of distribution-system dynamics, and can therefore mitigate disturbances precipitated fast time-varying loads and ambient conditions; however, they do not necessarily guarantee system-level optimality, and stability claims are mainly based on empirical evidences. On a different time scale, centralized and distributed optimal power flow (OPF) algorithms have been proposed to compute optimal steady-state inverter setpoints, so that power losses and voltage deviations are minimized and economic benefits to end-users providing ancillary services are maximized. However, traditional OPF schemes may offer decision making capabilities that do not match the dynamics of distribution systems. Particularly, during the time required to collect data from all the nodes of the network (e.g., loads), solve the OPF, and subsequently dispatch setpoints, the underlying load, ambient, and network conditions may have already changed; in this case, the DER output powers would be consistently regulated around outdated setpoints, leading to suboptimal system operation and violation of relevant electrical limits. The present work focuses on the synthesis of distributed RES-inverter controllers that leverage the opportunities for fast feedback offered by power-electronics interfaced RESs. The overarching objective is to bridge the temporal gap between long-term system optimization and real-time control, to enable seamless RES integration in large scale with stability and efficiency guarantees, while congruently pursuing system-level optimization objectives. The

  19. Strategies Unlimited.

    ERIC Educational Resources Information Center

    Blaga, Jeff; And Others

    Designed primarily for teachers of students in grades 7-12, the document presents over 60 social studies teaching strategies and lesson plans. Each lesson includes an overview, grade level information, suggested course/subject matter uses, objectives, suggested materials, student materials, and an instructional plan. Lesson topics fall into the…

  20. Strategies Unlimited.

    ERIC Educational Resources Information Center

    Blaga, Jeff; And Others

    Designed primarily for teachers of students in grades 7-12, the document presents over 60 social studies teaching strategies and lesson plans. Each lesson includes an overview, grade level information, suggested course/subject matter uses, objectives, suggested materials, student materials, and an instructional plan. Lesson topics fall into the…

  1. Educational Strategies.

    ERIC Educational Resources Information Center

    Journal of Chemical Education, 1983

    1983-01-01

    Highlights six papers presented at the Seventh Biennial Conference on Chemical Education (Stillwater, Oklahoma 1982). Topics addressed included college course using various instructional strategies, American Chemical Society services for secondary teachers, abstract reasoning unit for gifted elementary students, biographies of crystallographers,…

  2. Strategy under uncertainty.

    PubMed

    Courtney, H; Kirkland, J; Viguerie, P

    1997-01-01

    At the heart of the traditional approach to strategy lies the assumption that by applying a set of powerful analytic tools, executives can predict the future of any business accurately enough to allow them to choose a clear strategic direction. But what happens when the environment is so uncertain that no amount of analysis will allow us to predict the future? What makes for a good strategy in highly uncertain business environments? The authors, consultants at McKinsey & Company, argue that uncertainty requires a new way of thinking about strategy. All too often, they say, executives take a binary view: either they underestimate uncertainty to come up with the forecasts required by their companies' planning or capital-budging processes, or they overestimate it, abandon all analysis, and go with their gut instinct. The authors outline a new approach that begins by making a crucial distinction among four discrete levels of uncertainty that any company might face. They then explain how a set of generic strategies--shaping the market, adapting to it, or reserving the right to play at a later time--can be used in each of the four levels. And they illustrate how these strategies can be implemented through a combination of three basic types of actions: big bets, options, and no-regrets moves. The framework can help managers determine which analytic tools can inform decision making under uncertainty--and which cannot. At a broader level, it offers executives a discipline for thinking rigorously and systematically about uncertainty and its implications for strategy.

  3. Wind power generation and dispatch in competitive power markets

    NASA Astrophysics Data System (ADS)

    Abreu, Lisias

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

  4. Intracellular Parasite Invasion Strategies

    NASA Astrophysics Data System (ADS)

    Sibley, L. D.

    2004-04-01

    Intracellular parasites use various strategies to invade cells and to subvert cellular signaling pathways and, thus, to gain a foothold against host defenses. Efficient cell entry, ability to exploit intracellular niches, and persistence make these parasites treacherous pathogens. Most intracellular parasites gain entry via host-mediated processes, but apicomplexans use a system of adhesion-based motility called ``gliding'' to actively penetrate host cells. Actin polymerization-dependent motility facilitates parasite migration across cellular barriers, enables dissemination within tissues, and powers invasion of host cells. Efficient invasion has brought widespread success to this group, which includes Toxoplasma, Plasmodium, and Cryptosporidium.

  5. Power inverters

    SciTech Connect

    Miller, David H; Korich, Mark D; Smith, Gregory S

    2011-11-15

    Power inverters include a frame and a power module. The frame has a sidewall including an opening and defining a fluid passageway. The power module is coupled to the frame over the opening and includes a substrate, die, and an encasement. The substrate includes a first side, a second side, a center, an outer periphery, and an outer edge, and the first side of the substrate comprises a first outer layer including a metal material. The die are positioned in the substrate center and are coupled to the substrate first side. The encasement is molded over the outer periphery on the substrate first side, the substrate second side, and the substrate outer edge and around the die. The encasement, coupled to the substrate, forms a seal with the metal material. The second side of the substrate is positioned to directly contact a fluid flowing through the fluid passageway.

  6. RPS strategies to enable NASA's next decade robotic Mars missions

    NASA Technical Reports Server (NTRS)

    Balint, Tibor S.; Jordan, James F.

    2005-01-01

    This study examines the available power system options and power selection strategies in line with the proposed mission lineup, and identifies the benefits and utility of the various options for each of the next decade launch opportunities.

  7. Power transmission

    SciTech Connect

    Yale, O.S.

    1989-12-12

    This patent describes a power transmission. It comprises: in combination, a master gear having at least one annular tooth set, means for drivingly engaging the master gear with a power source, driven shaft, a yoke member attached to the shaft and including a screw pump housing extending radially with respect to the shaft with a pair of ports in spaced relation, a pump screw rotatable in the housing and a pump gear attached to the screw and engaging the annular tooth set, and a casing for transmission fluid. The pump housing being located for immersion in the fluid.

  8. Mitigation strategy

    NASA Astrophysics Data System (ADS)

    Carusi, Andrea; Perozzi, Ettore; Scholl, Hans

    2005-04-01

    There are three major options for mitigation of Near Earth Objects (NEOs). Deflection and disruption of NEOs require the development of new space technologies. A third option, the preparation of the target area on Earth to mitigate an impact, needs institutions for the required civil defense measures. The three options are complementary. Basic requirements for the presently most preferred strategy, deflection, are presented. To cite this article: A. Carusi et al., C. R. Physique 6 (2005).

  9. High power millimeter wave source development program

    NASA Technical Reports Server (NTRS)

    George, T. V.

    1989-01-01

    High power millimeter wave sources for fusion program; ECH source development program strategy; and 1 MW, 140 GHz gyrotron experiment design philosophy are briefly outlined. This presentation is represented by viewgraphs only.

  10. Electric Power: Decisions for the Future.

    ERIC Educational Resources Information Center

    Cardon, Phillip L.; Preston, John

    2003-01-01

    Reviews the past 25 years of electricity consumption in the United States and considers the implications for the near future. Discusses strategies for energy conservation and provides a student activity for measuring and conserving electric power. (Author/JOW)

  11. Power, Revisited

    ERIC Educational Resources Information Center

    Roscigno, Vincent J.

    2011-01-01

    Power is a core theoretical construct in the field with amazing utility across substantive areas, levels of analysis and methodologies. Yet, its use along with associated assumptions--assumptions surrounding constraint vs. action and specifically organizational structure and rationality--remain problematic. In this article, and following an…

  12. Star Power

    ScienceCinema

    None

    2016-07-12

    The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

  13. POWER SEWING.

    ERIC Educational Resources Information Center

    HILLINGER, YVONNE M.

    ALTHOUGH THE PRIMARY PURPOSE OF THIS STUDY GUIDE IS TO PROVIDE A TEXT IN POWER SEWING FOR DEAF PUPILS, IT CAN ALSO BE USED FOR STUDENTS WITH READING OR LEARNING DIFFICULTIES. DEVELOPED BY AN INSTRUCTOR WITH FACULTY HELP, THE TEXT FOLLOWS A COURSE OF STUDY APPROVED BY THE BOARD OF EDUCATION AND HAS BEEN TESTED IN VARIOUS CLASSROOMS. UNITS ARE --…

  14. Power Struggle.

    ERIC Educational Resources Information Center

    Cook, Glenn

    2001-01-01

    California's "power struggle" will probably not be replicated in the other 23 states that have deregulated electricity, but costs are rising everywhere. The Environmental Protection Agency/Department of Energy's new Energy Star online rating system should help school officials measure their buildings' efficiency and remove barriers to…

  15. Stigma power.

    PubMed

    Link, Bruce G; Phelan, Jo

    2014-02-01

    When people have an interest in keeping other people down, in or away, stigma is a resource that allows them to obtain ends they desire. We call this resource "stigma power" and use the term to refer to instances in which stigma processes achieve the aims of stigmatizers with respect to the exploitation, control or exclusion of others. We draw on Bourdieu (1987, 1990) who notes that power is often most effectively deployed when it is hidden or "misrecognized." To explore the utility of the stigma-power concept we examine ways in which the goals of stigmatizers are achieved but hidden in the stigma coping efforts of people with mental illnesses. We developed new self-report measures and administered them to a sample of individuals who have experienced mental illness to test whether results are consistent with the possibility that, in response to negative societal conceptions, the attitudes, beliefs and behaviors of people with psychosis lead them to be concerned with staying in, propelled to stay away and induced to feel downwardly placed - precisely the outcomes stigmatizers might desire. Our introduction of the stigma-power concept carries the possibility of seeing stigmatizing circumstances in a new light. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Power sprouts

    NASA Astrophysics Data System (ADS)

    French, M. M. J.

    2014-05-01

    This paper explains how a large number of sprouts were used as a battery of cells and connected together to power a set of LED Christmas lights. All relevant calculations to find the number of sprouts needed, their arrangement in series and parallel, the charge stored on the required capacitor and the capacitor charging time are illustrated.

  17. Power Trains.

    ERIC Educational Resources Information Center

    Kukuk, Marvin; Mathis, Joe

    This curriculum guide is part of a series designed to teach students about diesel engines. The materials in this power trains guide apply to both on-road and off-road vehicles and include information about chain and belt drives used in tractors and combines. These instructional materials, containing nine units, are written in terms of student…

  18. Star Power

    SciTech Connect

    2014-10-17

    The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

  19. Power, Revisited

    ERIC Educational Resources Information Center

    Roscigno, Vincent J.

    2011-01-01

    Power is a core theoretical construct in the field with amazing utility across substantive areas, levels of analysis and methodologies. Yet, its use along with associated assumptions--assumptions surrounding constraint vs. action and specifically organizational structure and rationality--remain problematic. In this article, and following an…

  20. Perpetual Power?

    SciTech Connect

    Madison, Alison L.

    2010-02-16

    This is a submission to Innovation Magazine for its January 2010 Clean-tech issue. The article discusses PNNL's award-winning Thermoelectric Ambient Energy Harvester technology, its license to Perpetua Power Source Technologies, Perpetua's subsequent product based on the PNNL technology, and where they're headed with it.

  1. Power Controller

    NASA Astrophysics Data System (ADS)

    1983-01-01

    The power factor controller (PFC) senses shifts in the relationship between voltage and current, and matches them with a motor's need. This prevents waste as motors do not need a high voltage when they are not operating at full load conditions. PFC is manufactured by Nordic Controls Company, among others, and has proved extremely cost effective.

  2. Power Struggle.

    ERIC Educational Resources Information Center

    Cook, Glenn

    2001-01-01

    California's "power struggle" will probably not be replicated in the other 23 states that have deregulated electricity, but costs are rising everywhere. The Environmental Protection Agency/Department of Energy's new Energy Star online rating system should help school officials measure their buildings' efficiency and remove barriers to…

  3. Future of United States Cyber: Examining the Past to Posture the Future

    DTIC Science & Technology

    2013-12-13

    adopting a new domain for military operations. The rise of air power during the first half of the 20th century and the ascension of space power during the...adopting a new domain for military operations. The rise of air power during the first half of the 20th century and the ascension of space power during...8 The Ascension of Space Power .................................................................................... 22 The Emergence of

  4. What Price Sovereignty? The Two Faces of Engagement and the Paradox of Power: A Comparison of the Security and Grand Strategies of the United States and the European Union

    DTIC Science & Technology

    2012-01-01

    according to James Harper, various actors in successive Roosevelt Administrations had competing views for how to handle “the European Question.” 37...Europe. 14 Culture and politics do not change independently. 55 During the post–war occupation of Germany, according to Petra Goedde, the power...15-335. 55 Petra Goedde, GIs and Germans: Culture, Gender, and Foreign Relations, 1945-1949 (New Haven: Yale University Press, 2003), xvii. 56

  5. Power superconducting power transmission cable

    DOEpatents

    Ashworth, Stephen P.

    2003-01-01

    The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

  6. Power superconducting power transmission cable

    DOEpatents

    Ashworth, Stephen P.

    2003-06-10

    The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

  7. Power converter

    NASA Technical Reports Server (NTRS)

    Black, J. M. (Inventor)

    1981-01-01

    A dc-to-dc converter employs four transistor switches in a bridge to chop dc power from a source, and a voltage multiplying diode rectifying ladder network to rectify and filter the chopped dc power for delivery to a load. The bridge switches are cross coupled in order for diagonally opposite pairs to turn on and off together using RC networks for the cross coupling to achieve the mode of operation of a free running multivibrator, and the diode rectifying ladder is configured to operate in a push-pull mode driven from opposite sides of the multivibrator outputs of the ridge switches. The four transistor switches provide a square-wave output voltage which as a peak-to-peak amplitude that is twice the input dc voltage, and is thus useful as a dc-to-ac inverter.

  8. Surface Force Strategy: Return to Sea Control

    DTIC Science & Technology

    2016-01-01

    trategy orce urfaceS F S Return to Sea Control Surface Force Strategy Return to Sea Control 14 Return to Sea Control Return to Sea Control A quarter...Responding to the call to “strengthen naval power at and from the sea,” the U.S. Naval Surface Force submits this “Surface Force Strategy .” The... strategy describes the return to sea control and implementation of Distributed Lethality as an operational and organizational principle for achieving

  9. Power saw

    NASA Technical Reports Server (NTRS)

    Bradley, Jimmy D. (Inventor)

    1991-01-01

    A power saw is disclosed for space or robotic operations with jaw members for clamping to a work piece by an operation of a lever arm. The saw assembly is slidably mounted on the jaw assembly and fed into the work piece by a hand operated feed screw. The saw assembly includes a motor and gear belt. A current sensing circuit provides a current signal which actuates colored lights to visually depict the load on the saw blade during the cutting operations.

  10. Power supply

    DOEpatents

    Hart, Edward J.; Leeman, James E.; MacDougall, Hugh R.; Marron, John J.; Smith, Calvin C.

    1976-01-01

    An electric power supply employs a striking means to initiate ferroelectric elements which provide electrical energy output which subsequently initiates an explosive charge which initiates a second ferroelectric current generator to deliver current to the coil of a magnetic field current generator, creating a magnetic field around the coil. Continued detonation effects compression of the magnetic field and subsequent generation and delivery of a large output current to appropriate output loads.

  11. Power sources.

    PubMed

    Luciano, A A

    1995-09-01

    The rapid development of endoscopic surgery has created an ever-increasing demand for new instruments, such as lasers of various wavelengths, and new applications of high-frequency electrosurgery. The technology has advanced rapidly and it is sometimes difficult to understand the different applications of these new instruments and take full advantage of these developments. This article has reviewed the basic principles of the various power sources commonly utilized in gynecologic surgery and described the clinical applications of each of them.

  12. Stigma Power

    PubMed Central

    Link, Bruce G.; Phelan, Jo

    2015-01-01

    When people have an interest in keeping other people down, in or away, stigma is a resource that allows them to obtain ends they desire. We call this resource “stigma power” and use the term to refer to instances in which stigma processes achieve the aims of stigmatizers with respect to the exploitation, control or exclusion of others. We draw on Bourdieu (1987; 1990) who notes that power is often most effectively deployed when it is hidden or “misrecognized.” To explore the utility of the stigma power concept we examine ways in which the goals of stigmatizers are achieved but hidden in the stigma coping efforts of people with mental illnesses. We developed new self-report measures and administered them to a sample of individuals who have experienced mental illness to test whether results are consistent with the possibility that, in response to negative societal conceptions, the attitudes, beliefs and behaviors of people with psychosis lead them to be concerned with staying in, propelled to stay away and induced to feel downwardly placed –precisely the outcomes stigmatizers might desire. Our introduction of the stigma power concept carries the possibility of seeing stigmatizing circumstances in a new light. PMID:24507908

  13. Sex-Role, Self-Concept and Power in Intimate Relationships.

    ERIC Educational Resources Information Center

    Falbo, Toni; Peplau, Letitia Anne

    Research with a two-dimensional model of power strategies used in intimate relationships has found that men are more likely to report using direct bilateral strategies, while women are more likely to report using indirect, unilateral strategies. The relationships among sex-role, self-concept, and the power strategies used in intimate relationships…

  14. Global implications of standby power use

    SciTech Connect

    Lebot, Benoit; Meier, Alan; Anglade, Alain

    2000-05-01

    Separate studies indicate that standby power is responsible for 20-60 W per home in developed countries. Standby power is responsible for about 2% of OECD countries total electricity consumption and the related power generation generates almost 1% of their carbon emissions. Replacement of existing appliances with those appliances having the lowest standby would reduce total standby power consumption by over 70%. The resulting reductions in carbon emissions would meet over 3% of OECD's total Kyoto commitments. Other strategies may cut more carbon emissions, but standby power is unique in that the reductions are best accomplished through international collaboration and whose costs and large benefits would be spread over all countries.

  15. Limits of Military Power for National Security.

    ERIC Educational Resources Information Center

    Melman, Seymour

    1981-01-01

    Reviews the post World War II nuclear-military arms race and claims that it is possible to define significant limits of military power for national security. Topics discussed include public opinion regarding the arms race, constraints on military power, conventional forces, checkmating conventional strategy, and the seriousness of nuclear false…

  16. Implementation Strategy

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Meeting the identified needs of Earth science requires approaching EOS as an information system and not simply as one or more satellites with instruments. Six elements of strategy are outlined as follows: implementation of the individual discipline missions as currently planned; use of sustained observational capabilities offered by operational satellites without waiting for the launch of new mission; put first priority on the data system; deploy an Advanced Data Collection and Location System; put a substantial new observing capability in a low Earth orbit in such a way as to provide for sustained measurements; and group instruments to exploit their capabilities for synergism; maximize the scientific utility of the mission; and minimize the costs of implementation where possible.

  17. Visual analytics for power grid contingency analysis.

    PubMed

    Pak Chung Wong; Zhenyu Huang; Yousu Chen; Mackey, Patrick; Shuangshuang Jin

    2014-01-01

    Contingency analysis employs different measures to model scenarios, analyze them, and then derive the best response to any threats. A proposed visual-analytics pipeline for power grid management can transform approximately 100 million contingency scenarios to a manageable size and form. Grid operators can examine individual scenarios and devise preventive or mitigation strategies in a timely manner. Power grid engineers have applied the pipeline to a Western Electricity Coordinating Council power grid model.

  18. Cyber Power

    DTIC Science & Technology

    2010-05-01

    concept of A’s power over B is for the description of the policy possibilities open to A.”5 In Max Weber’s view, we want to know the probability that an...name system of internet addresses starts in 1983, and the first computer viruses were created about that time. The World Wide Web begins in 1989...carrier task forces and submarine fleets create enor- mous barriers to entry and make it still possible to speak of American naval dominance. While

  19. Metal-mediated controllable creation of secondary, tertiary, and quaternary carbon centers: a powerful strategy for the synthesis of iron, cobalt, and copper complexes with in situ generated substituted 1-pyridineimidazo[1,5-a]pyridine ligands.

    PubMed

    Chen, Yanmei; Li, Lei; Chen, Zhou; Liu, Yonglu; Hu, Hailiang; Chen, Wenqian; Liu, Wei; Li, Yahong; Lei, Tao; Cao, Yanyuan; Kang, Zhenghui; Lin, Miaoshui; Li, Wu

    2012-09-17

    An efficient strategy for the synthesis of a wide variety of coordination complexes has been developed. The synthetic protocol involves a solvothermal in situ metal-ligand reaction of picolinaldehyde, ammonium acetate, and transition-metal ions, leading to the generation of 12 coordination complexes supported by a novel class of substituted 1-pyridineimidazo[1,5-a]pyridine ligands (L1-L5). The ligands L1-L5 were afforded by metal-mediated controllable conversion of the aldehyde group of picolialdehyde into a ketone and secondary, tertiary, and quaternary carbon centers, respectively. Complexes of various nuclearities were obtained: from mono-, di-, and tetranuclear to 1D chain polymers. The structures of the in situ formed complexes could be controlled rationally via the choice of appropriate starting materials and tuning of the ratio of the starting materials. The plausible mechanisms for the formation of the ligands L1-L5 were proposed.

  20. Power system requirements and definition for lunar and Mars outposts

    NASA Technical Reports Server (NTRS)

    Petri, D. A.; Cataldo, R. L.; Bozek, J. M.

    1990-01-01

    Candidate power systems being considered for outpost facilities (stationary power systems) and vehicles (mobile systems) are discussed, including solar, chemical, isotopic, and reactor. The current power strategy was an initial outpost power system composed of photovoltaic arrays for daytime energy needs and regenerative fuel cells for power during the long lunar night. As day and night power demands grow, the outpost transitions to nuclear-based power generation, using thermoelectric conversion initially and evolving to a dynamic conversion system. With this concept as a guideline, a set of requirements has been established, and a reference definition of candidate power systems meeting these requirements has been identified.

  1. Business Pattern of Distributed Energy in Electric Power System Reformation

    NASA Astrophysics Data System (ADS)

    Liang, YUE; Zhuochu, LIU; Jun, LI; Siwei, LI

    2017-05-01

    Under the trend of the electric power system revolution, the operation mode of micro power grid that including distributed power will be more diversified. User’s demand response and different strategies on electricity all have great influence on the operation of distributed power grid. This paper will not only research sensitive factors of micro power grid operation, but also analyze and calculate the cost and benefit of micro power grid operation upon different types. Then it will build a tech-economic calculation model, which applies to different types of micro power grid under the reformation of electric power system.

  2. Power system requirements and definition for lunar and Mars outposts

    NASA Technical Reports Server (NTRS)

    Petri, D. A.; Cataldo, R. L.; Bozek, J. M.

    1990-01-01

    Candidate power systems being considered for outpost facilities (stationary power systems) and vehicles (mobile systems) are discussed, including solar, chemical, isotopic, and reactor. The current power strategy was an initial outpost power system composed of photovoltaic arrays for daytime energy needs and regenerative fuel cells for power during the long lunar night. As day and night power demands grow, the outpost transitions to nuclear-based power generation, using thermoelectric conversion initially and evolving to a dynamic conversion system. With this concept as a guideline, a set of requirements has been established, and a reference definition of candidate power systems meeting these requirements has been identified.

  3. Spacepower for Australias Security - Grand Strategy or Strategy of Grandeur

    DTIC Science & Technology

    2012-06-01

    Forces operations, cyber - attacks , and many other military operations. The critical conclusion to be made is that systems analysis forms an...already has an enduring partnership with the US that could be strengthened for space, in the same way that a cyber - attack on either country is now a...land, air, sea and cyber domains. Spacepower emerges as a unique element of national power, and an essential element of grand strategy for the

  4. Power optics

    SciTech Connect

    Apollonov, V V

    2014-02-28

    By using the theory we developed in the early 1970s, a broad range of phenomena is considered for an optical surface of a solid body that is exposed to radiation arbitrarily varying in time and producing temperature fields, thermoelastic stresses and thermal deformations on the surface layer. The examination is based on the relations (which are similar to Duhamel's integral formula from the theory of heat conduction) between the quantities characterising the thermal stress state in any nonstationary regimes of energy input into a solid. A peculiar feature of the analysis of the thermal stress state in this case consists in the fact that this relation comprises time as a parameter, which in turn is a consequence of incoherence of the quasi-stationary problem of thermoelasticity. This phenomenon is particularly important for the optics of high-power, high-pulse repetition rate lasers, which are being actively developed. In the review, we have recently published in Laser Physics, the thermal stress state of a solid is analysed. In this state, time is treated as an independent variable used in differentiation. Such an approach greatly reduces the applicability of the method. The review published contains data on the use of capillary porous structures made of various materials with different degrees of the surface development. Moreover, such structures can be efficiently employed to increase the heat exchange at a temperature below the boiling point of the coolant. In the present review we discuss the dependences of the limiting laser intensities on the duration of a pulse or a pulse train, corresponding to the three stages of the state of the reflecting surface and leading to unacceptable elastic deformations of the surface, to the plastic yield of the material accompanied by the formation of residual stresses and to the melting of the surface layer. We also analyse the problem of heat exchange in the surface layer with a liquid metal coolant pumped through it. The

  5. Power oscillator

    DOEpatents

    Gitsevich, Aleksandr

    2001-01-01

    An oscillator includes an amplifier having an input and an output, and an impedance transformation network connected between the input of the amplifier and the output of the amplifier, wherein the impedance transformation network is configured to provide suitable positive feedback from the output of the amplifier to the input of the amplifier to initiate and sustain an oscillating condition, and wherein the impedance transformation network is configured to protect the input of the amplifier from a destructive feedback signal. One example of the oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to match the driving frequency of the oscillator to a plurality of tuning states of the lamp.

  6. POWER REACTOR

    DOEpatents

    Zinn, W.H.

    1958-07-01

    A fast nuclear reactor system ls described for producing power and radioactive isotopes. The reactor core is of the heterogeneous, fluid sealed type comprised of vertically arranged elongated tubular fuel elements having vertical coolant passages. The active portion is surrounded by a neutron reflector and a shield. The system includes pumps and heat exchangers for the primary and secondary coolant circuits. The core, primary coolant pump and primary heat exchanger are disposed within an irapenforate tank which is filled with the primary coolant, in this case a liquid metal such as Na or NaK, to completely submerge these elements. The tank is completely surrounded by a thick walled concrete shield. This reactor system utilizes enriched uranium or plutonium as the fissionable material, uranium or thorium as a diluent and thorium or uranium containing less than 0 7% of the U/sup 235/ isotope as a fertile material.

  7. Patriarchy, power, and female masculinity.

    PubMed

    Nguyen, Athena

    2008-01-01

    This article examines the place of "butch" within the women's movement. The political potentials of butch in both her refusal of patriarchal constructs of femininity and her transmutation of masculinity will be explored. It will be argued that the butch lesbian threatens male power by severing the naturalized connection between masculinity and male bodies, by causing masculinity to appear "queer," and by usurping men's roles. However, for "butch" to truly have feminist potential, it also needs to be accompanied by a feminist awareness and a rejection of aspects of masculinity that are oppressive to women. Hence, "butch feminist" need not be an oxymoron, but a strategy for challenging male domination and power.

  8. Three strategies for conservation

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The three strategies considered as energy conservation oriented were given: national energy conservation, electrification, and diversification. The first one applies to the near term period (now-1985), the second one to the mid term (1985-2000), and the third one to the far term (2000- ). The rest of this section was focussed on the near term period. The following proposed actions were considered: (1) roll back the price of newly discovered oil, (2) force conversion of many power plants from gas and oil to coal, (3) freeze gasoline production for three years at 1972 levels, (4) mandate automobile mileage requirements, (5) require industry to improve energy efficiency, and (6) require manufacture of household appliances with greater efficiency. Each of these six actions was described and discussed in more detail.

  9. Key strategies for enhancing the cycling stability and rate capacity of LiNi0.5Mn1.5O4 as high-voltage cathode materials for high power lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Yi, Ting-Feng; Mei, Jie; Zhu, Yan-Rong

    2016-06-01

    Spinel LiNi0.5Mn1.5O4 (LNMO) is one of the most promising high voltage cathode materials for future application due to its advantages of large reversible capacity, high thermal stability, low cost, environmental friendliness, and high energy density. LNMO can provide 20% and 30% higher energy density than traditional cathode materials LiCoO2 and LiFePO4, respectively. Unfortunately, LNMO-based batteries with LiPF6-based carbonate electrolytes always suffer from severe capacity deterioration and poor thermostability because of the oxidization of organic carbonate solvents and decomposition of LiPF6, especially at elevated temperatures and water-containing environment. Hence, it is necessary to systematically and comprehensively summarize the progress in understanding and modifying LNMO cathode from various aspects. In this review, the structure, transport properties and different reported possible fading mechanisms of LNMO cathode are first discussed detailedly. And then, the major goal of this review is to highlight new progress in using proposed strategies to improve the cycling stability and rate capacity of LNMO-based batteries, including synthesis, control of special morphologies, element doping and surface coating etc., especially at elevated temperatures. Finally, an insight into the future research and further development of LNMO cathode is discussed.

  10. Population strategy.

    PubMed

    Kunii, C

    1989-12-01

    In this article, Chojiro Kunii, chairman and executive director of the Japanese Organization for International Cooperation in Family Planning (JOICFP), briefly describes the evolution of the INtegrated Family Planning, Nutrition, and Parasite Control Project (IP). The IP project began in Japan during the post-war period, when midwives and public health nurses introduced family planning alongside maternal and child health care services to make it more acceptable to people. Based on Japan's experience, JOICFP formed an international cooperation project based on parasite control, family planning, and nutrition. Introduced in several Asian countries in the mid-1970s, the project was quickly transported to Central and South America. And in 1983, Africa witnesses its first IP project. This took place in the Masama district of Tanzania, where the results of deworming quickly captures the attention of the population, making it easier for family planning workers to spread their message. In the 2 regions where the IP project was introduced, contraceptive prevalence among women has increased from 9.3% to 33%, and from 27% to 60%. Tanzania is now considering incorporating the IP project in its next 5-year development plan. Other African countries have followed suit. Kunii explains that JOICFP's Ip project enjoys support from both IPPF and UNFPA. He adds that, for its 2nd stage of development, the IP project hopes to become a union of family planning and preventive health. This new phase can already be observed in Asian countries. In developing its population strategy, JOICFP learned from the experience' of Japan, which demonstrated the importance of balancing quantity and quality.

  11. Life After the George W. Bush Administration: A New US Strategy Towards China for Future Administrations

    DTIC Science & Technology

    2008-05-15

    grand strategy is required. Contemporary International Relations Theories Literary Nobel Prize winner Bertrand Russell wrote, “Love of power, like...strategy, a comprehensive look at current international relations theories and how these theories help provide a framework for grand strategy is...recommended strategy towards China. To provide a recommended strategy, a comprehensive look at current international relations theories and how these

  12. Power management system

    DOEpatents

    Algrain, Marcelo C.; Johnson, Kris W.; Akasam, Sivaprasad; Hoff, Brian D.

    2007-10-02

    A method of managing power resources for an electrical system of a vehicle may include identifying enabled power sources from among a plurality of power sources in electrical communication with the electrical system and calculating a threshold power value for the enabled power sources. A total power load placed on the electrical system by one or more power consumers may be measured. If the total power load exceeds the threshold power value, then a determination may be made as to whether one or more additional power sources is available from among the plurality of power sources. At least one of the one or more additional power sources may be enabled, if available.

  13. Green Power Partnership Videos

    EPA Pesticide Factsheets

    The Green Power Partnership develops videos on a regular basis that explore a variety of topics including, Green Power partnership, green power purchasing, Renewable energy certificates, among others.

  14. A passive satellite deorbiting strategy for medium earth orbit using solar radiation pressure and the J2 effect

    NASA Astrophysics Data System (ADS)

    Lücking, Charlotte; Colombo, Camilla; McInnes, Colin R.

    2012-08-01

    The growing population of space debris poses a serious risk to the future of space flight. To effectively manage the increase of debris in orbit, end-of life disposal has become a key requirement for future missions. This poses a challenge for Medium Earth Orbit (MEO) spacecraft which require a large Δv to re-enter the atmosphere or reach the geostationary graveyard orbit. This paper further explores a passive strategy based on the joint effects of solar radiation pressure and the Earth's oblateness acting on a high area-to-mass-ratio object. The concept was previously presented as an analytical planar model. This paper uses a full 3D model to validate the analytical results numerically for equatorial circular orbits first, then investigating higher inclinations. It is shown that for higher inclinations the initial position of the Sun and right ascension of the ascending node become increasingly important. A region of very low required area-to-mass-ratio is identified in the parameter space of semi-major axis and inclination which occurs for altitudes below 10,000 km.

  15. Strategy and the Internet.

    PubMed

    Porter, M E

    2001-03-01

    Many of the pioneers of Internet business, both dot-coms and established companies, have competed in ways that violate nearly every precept of good strategy. Rather than focus on profits, they have chased customers indiscriminately through discounting, channel incentives, and advertising. Rather than concentrate on delivering value that earns an attractive price from customers, they have pursued indirect revenues such as advertising and click-through fees. Rather than make trade-offs, they have rushed to offer every conceivable product or service. It did not have to be this way--and it does not have to be in the future. When it comes to reinforcing a distinctive strategy, Michael Porter argues, the Internet provides a better technological platform than previous generations of IT. Gaining competitive advantage does not require a radically new approach to business; it requires building on the proven principles of effective strategy. Porter argues that, contrary to recent thought, the Internet is not disruptive to most existing industries and established companies. It rarely nullifies important sources of competitive advantage in an industry; it often makes them even more valuable. And as all companies embrace Internet technology, the Internet itself will be neutralized as a source of advantage. Robust competitive advantages will arise instead from traditional strengths such as unique products, proprietary content, and distinctive physical activities. Internet technology may be able to fortify those advantages, but it is unlikely to supplant them. Porter debunks such Internet myths as first-mover advantage, the power of virtual companies, and the multiplying rewards of network effects. He disentangles the distorted signals from the marketplace, explains why the Internet complements rather than cannibalizes existing ways of doing business, and outlines strategic imperatives for dot-coms and traditional companies.

  16. All strategy is local.

    PubMed

    Greenwald, Bruce; Kahn, Judd

    2005-09-01

    The aim of strategy is to master a market environment by understanding and anticipating the actions of other economic agents, especially competitors. A firm that has some sort of competitive advantage-privileged access to customers, for instance--will have relatively few competitors to contend with, since potential competitors without an advantage, if they have their wits about them, will stay away. Thus, competitive advantages are actually barriers to entry and vice versa. In markets that are exposed, by contrast, competition is intense. If the incumbents have even brief success in earning greater than normal returns on investments, new entrants will swarm in to grab a share of the profits. Sooner or later, the additional competition will push returns as far down as the firms' costs of capital. For firms operating in such markets, the only choice is to forget about strategy and run the business as efficiently as possible. Barriers to entry are easier to maintain in a competitive arena that is "local", either in the geographic sense or in the sense of being limited to one product or a handful of related ones. The two most powerful competitive advantages-customer captivity and economies of scale-are more achievable and sustainable in circumscribed markets of this kind. Their opposites are the open markets and host of rivals that are features of globalization. Compapies entering such markets risk frittering away the advantages they secured on smaller playing fields.., Ifa company wants to grow but still obtain superior returns, the authors argue, the best strategy is to dominate a series of discrete but preferably contiguous markets and then expand only at their edges. WalMart's diminishing margins over the past 15 years are strong evidence of the danger of proceeding otherwise.

  17. Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems. Volume 3, Appendix B: NO{sub x} and alkali vapor control strategies: Final report

    SciTech Connect

    Not Available

    1990-07-01

    CRS Sirrine (CRSS) is evaluating a novel IGCC process in which gases exiting the gasifier are burned in a gas turbine combustion system. The turbine exhaust gas is used to generate additional power in a conventional steam generator. This results in a significant increase in efficiency. However, the IGCC process requires development of novel approaches to control SO{sub 2} and NO{sub x} emissions and alkali vapors which can damage downstream turbine components. Ammonia is produced from the reaction of coal-bound nitrogen with steam in the reducing zone of any fixed bed coal gasifier. This ammonia can be partially oxidized to NO{sub x} when the product gas is oxidized in a gas turbine combustor. Alkali metals vaporize in the high-temperature combustion zone of the gasifier and laser condense on the surface of small char or ash particles or on cooled metal surfaces. It these alkali-coated materials reach the gas turbine combustor, the alkali will revaporize condense on turbine blades and cause rapid high temperature corrosion. Efficiency reduction will result. PSI Technology Company (PSIT) was contracted by CRSS to evaluate and recommend solutions for NO{sub x} emissions and for alkali metals deposition. Various methods for NO{sub x} emission control and the potential process and economic impacts were evaluated. This included estimates of process performance, heat and mass balances around the combustion and heat transfer units and a preliminary economic evaluation. The potential for alkali metal vaporization and condensation at various points in the system was also estimated. Several control processes and evaluated, including an order of magnitude cost for the control process.

  18. Political economy of power liberalization and power transformation

    NASA Astrophysics Data System (ADS)

    Yu, Jung-Min

    2009-12-01

    Since the mid-1980s, power sector liberalization has been embraced at various levels across the world. The dominant rationale underlying such a move is that of efficiency improvement to be purportedly achieved by substituting private for public ownership and markets for regulations. However, the evidence of market-oriented power sector reform has shown environmental unsustainability, economic instability, and centralized technocracy. It is argued here that these problems are due to the continued commitment to the conventional energy paradigm, rather than being the results of operational mismanagement. This dissertation will challenge the adequacy of the efficiency discourse that has been predominant in power sector reform by broadening the scope of the energy discourse to socio-political and environmental dimensions. Instead of power liberalization driven by an energy commodity and centralization paradigm, this dissertation contends that power transformation based on an alternative paradigm of energy commons and decentralization is necessary. Synergistic and neoliberal development of South Korea since the 1960s is critically analyzed using the theoretical framework of energy paradigm. The case study of South Korea attempts to provide an understanding of how the conventional energy paradigm was first established and then expanded, and how it responded to the social, environmental and economic anomalies in a specific political economic context. As an alternative to the power liberalization strategy, this dissertation proposes a local energy regime based on the paradigm of energy commons and decentralization.

  19. (Mis)Understanding Strategy as a "Spectacular Intervention": A Phenomenological Reflection on the Strategy Orientations Underpinning School Improvement in England

    ERIC Educational Resources Information Center

    Bates, Agnieszka

    2014-01-01

    The introduction of the "National Strategies" for primary education in 1998, positioned "strategy" as a powerful instrument for mobilising the school "workforce" in England in the cause of continuous improvement. Government approaches to strategy formulation and enactment appear to reflect an instrumentalist…

  20. (Mis)Understanding Strategy as a "Spectacular Intervention": A Phenomenological Reflection on the Strategy Orientations Underpinning School Improvement in England

    ERIC Educational Resources Information Center

    Bates, Agnieszka

    2014-01-01

    The introduction of the "National Strategies" for primary education in 1998, positioned "strategy" as a powerful instrument for mobilising the school "workforce" in England in the cause of continuous improvement. Government approaches to strategy formulation and enactment appear to reflect an instrumentalist…

  1. Optimal Dispatch of Competitive Power Markets by Using PowerWorld Simulator

    NASA Astrophysics Data System (ADS)

    Zhang, Dong; Li, Shuhui

    2013-10-01

    The transition to competitive and retail markets for electric utilities around the world has been a difficult and controversial process. One of the difficulties that hindered the development and growth of competitive power markets is the absence of efficient computational tools to assist the design, analysis, and operation of competitive power markets. PowerWorld simulator is a software package that has strong analytical and visualization functions suitable for extensive power flow study of an electric power system. However, like many other power flow simulators, PowerWorld cannot be used directly for analysis and evaluation of a competitive power market. This article investigates mathematical models associated with a competitive power market and how these models can be converted and transformed in such a way that makes it possible to use PowerWorld for the competitive power market study. To validate the effectiveness of the proposed strategy, models of several small-scale competitive power markets are built in MatLab by using conventional approaches. Results generated by both PowerWorld and MatLab are compared. Finally, the article demonstrates how the PowerWorld simulator is used to investigate a larger and practical competitive power system.

  2. Power Block Geometry Applied to the Building of Power Electronics Converters

    ERIC Educational Resources Information Center

    dos Santos, E. C., Jr.; da Silva, E. R. C.

    2013-01-01

    This paper proposes a new methodology, Power Block Geometry (PBG), for the presentation of power electronics topologies that process ac voltage. PBG's strategy uses formal methods based on a geometrical representation with particular rules and defines a universe with axioms and conjectures to establish a formation law. It allows power…

  3. Power Block Geometry Applied to the Building of Power Electronics Converters

    ERIC Educational Resources Information Center

    dos Santos, E. C., Jr.; da Silva, E. R. C.

    2013-01-01

    This paper proposes a new methodology, Power Block Geometry (PBG), for the presentation of power electronics topologies that process ac voltage. PBG's strategy uses formal methods based on a geometrical representation with particular rules and defines a universe with axioms and conjectures to establish a formation law. It allows power…

  4. Power Sources for Ultra Low Power Electronics

    DTIC Science & Technology

    2000-06-12

    DARPA asked JASON to examine the issue of power sources for low power electronics with a specific emphasis on the properties of nuclear batteries and...integrated power sources combining power and electronics. During the 1998 Summer Study a workshop was held to provide background for the study, with

  5. Soldier System Power Sources

    DTIC Science & Technology

    2006-12-31

    capability 21 Photovoltaic Power Sources 23 Maximum Power Tracking in Solar Arrays 23 Optimum Configuration of Solar Array for Enhanced Power Generation...Sources", IEEE Transactions on Power Elec- tronics, vol. 20, No. 1, pp. 244-253, Jan. 2005. 9. S. Liu, R. Dougal, E. Solodovnik, "Maximum Power Tracking and...eguate FRetulat Fig. 5.5. Flow chart of control algorithm. 22 Soldier System Power Sources Final Project Report PHOTOVOLTAIC POWER SOURCES MAXIMUM POWER

  6. Maximum Power Training and Plyometrics for Cross-Country Running.

    ERIC Educational Resources Information Center

    Ebben, William P.

    2001-01-01

    Provides a rationale for maximum power training and plyometrics as conditioning strategies for cross-country runners, examining: an evaluation of training methods (strength training and maximum power training and plyometrics); biomechanic and velocity specificity (role in preventing injury); and practical application of maximum power training and…

  7. Maximum Power Training and Plyometrics for Cross-Country Running.

    ERIC Educational Resources Information Center

    Ebben, William P.

    2001-01-01

    Provides a rationale for maximum power training and plyometrics as conditioning strategies for cross-country runners, examining: an evaluation of training methods (strength training and maximum power training and plyometrics); biomechanic and velocity specificity (role in preventing injury); and practical application of maximum power training and…

  8. Power Is Not a "Four-Letter Word."

    ERIC Educational Resources Information Center

    Smaby, Marlowe H.; And Others

    1988-01-01

    Proposes tentative model for considering the nature of power and how counselors might use power to influence those who have impact on their clients and programs. Presents power strategies framework based on differing levels of interpersonal relationships as way to bring about desired change in interpersonal situations that are harmful to clients…

  9. Power modules and projected power systems evolution

    NASA Technical Reports Server (NTRS)

    Brantley, L. W.

    1978-01-01

    Photovoltaic, solar thermal, and nuclear power systems are considered to supply future earth orbital electrical power requirements. A growth scenario from a 25-kW Power Module in the early Shuttle era to the 5- to 10-GW Satellite Power System in the year 2000 is presented. Photovoltaic systems are presently baselined in this evolution. The Photovoltaic Power System and subsystem growth projections, consistent with this scenario, were developed and are summarized.

  10. Women, Power, and Libraries.

    ERIC Educational Resources Information Center

    Schuman, Patricia Glass

    1984-01-01

    Discusses the concept of power in the context of women and the library profession, citing views of power by Max Weber, John Kenneth Galbraith, Letty Cottin Pogrebin, and Rosabeth Moss Kantor. Male power and female submission, defining power, organizing for power, and sharing power are highlighted. A 12-item bibliography is included. (EJS)

  11. Women, Power, and Libraries.

    ERIC Educational Resources Information Center

    Schuman, Patricia Glass

    1984-01-01

    Discusses the concept of power in the context of women and the library profession, citing views of power by Max Weber, John Kenneth Galbraith, Letty Cottin Pogrebin, and Rosabeth Moss Kantor. Male power and female submission, defining power, organizing for power, and sharing power are highlighted. A 12-item bibliography is included. (EJS)

  12. Political strategy, business strategy, and the academic medical center: linking theory and practice.

    PubMed

    Souba, W W; Weitekamp, M R; Mahon, J F

    2001-09-01

    The purpose of this paper is to link external political strategy theory to a specific health care setting-that of the academic medical center (AMC). Political strategy encompasses those activities undertaken by AMCs to acquire, develop, and use power (clout, influence, and credibility) to gain an advantage in situations of conflict. It should be differentiated from internal politics, a topic that will not be dealt with in this review. Political strategy should also be distinguished from but not divorced from competitive strategy. As political and social action can change the competitive landscape and the rules of competition, AMCs must become adept in issues management and stakeholder management. The focus on political strategy is a reflection of the enormous changes in the external environment that have impacted AMCs in recent years. These changes have often emerged out of political and social action and they impact significantly on the organization's more traditional business strategies. We suggest that a tighter alignment between political and business strategies in the future will help ensure organizational survival and success. This article reviews the literature and theory in corporate political strategy and illustrates the application of political strategy with examples of issues and problems faced by AMCs. Models of political strategy are well crafted, and this article concludes with succinct observations on the use of political strategies to enhance the business-based strategies of AMCs. Although the focus is on AMCs, the use of political strategies is applicable to any health care institution. Copyright 2001 Academic Press.

  13. Optimal GENCO bidding strategy

    NASA Astrophysics Data System (ADS)

    Gao, Feng

    Electricity industries worldwide are undergoing a period of profound upheaval. The conventional vertically integrated mechanism is being replaced by a competitive market environment. Generation companies have incentives to apply novel technologies to lower production costs, for example: Combined Cycle units. Economic dispatch with Combined Cycle units becomes a non-convex optimization problem, which is difficult if not impossible to solve by conventional methods. Several techniques are proposed here: Mixed Integer Linear Programming, a hybrid method, as well as Evolutionary Algorithms. Evolutionary Algorithms share a common mechanism, stochastic searching per generation. The stochastic property makes evolutionary algorithms robust and adaptive enough to solve a non-convex optimization problem. This research implements GA, EP, and PS algorithms for economic dispatch with Combined Cycle units, and makes a comparison with classical Mixed Integer Linear Programming. The electricity market equilibrium model not only helps Independent System Operator/Regulator analyze market performance and market power, but also provides Market Participants the ability to build optimal bidding strategies based on Microeconomics analysis. Supply Function Equilibrium (SFE) is attractive compared to traditional models. This research identifies a proper SFE model, which can be applied to a multiple period situation. The equilibrium condition using discrete time optimal control is then developed for fuel resource constraints. Finally, the research discusses the issues of multiple equilibria and mixed strategies, which are caused by the transmission network. Additionally, an advantage of the proposed model for merchant transmission planning is discussed. A market simulator is a valuable training and evaluation tool to assist sellers, buyers, and regulators to understand market performance and make better decisions. A traditional optimization model may not be enough to consider the distributed

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

    NASA Astrophysics Data System (ADS)

    Jiang, Zhenhua

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

  15. The New Maritime Strategy -- A Chance for Greater Relevance?

    DTIC Science & Technology

    2008-03-25

    together in a voluntary global-coalition to share information and police the world’s oceans against pirates, organized crime, human smugglers, and...buy the resources that support tactics).20 The point here is that a strategy should be just that, a strategy. Producing a strategy which lays out... resources required to implement the strategy could cause a premature failure if such resources are never obtained. Armed with the vision of Sea Power

  16. Dynamic power flow controllers

    DOEpatents

    Divan, Deepakraj M.; Prasai, Anish

    2017-03-07

    Dynamic power flow controllers are provided. A dynamic power flow controller may comprise a transformer and a power converter. The power converter is subject to low voltage stresses and not floated at line voltage. In addition, the power converter is rated at a fraction of the total power controlled. A dynamic power flow controller controls both the real and the reactive power flow between two AC sources having the same frequency. A dynamic power flow controller inserts a voltage with controllable magnitude and phase between two AC sources; thereby effecting control of active and reactive power flows between two AC sources.

  17. Power in everyday life.

    PubMed

    Smith, Pamela K; Hofmann, Wilhelm

    2016-09-06

    How does power manifest itself in everyday life? Using experience-sampling methodology, we investigated the prevalence, sources, and correlates of power in people's natural environments. Participants experienced power-relevant situations regularly, though not frequently. High power was not restricted to a limited few: almost half of the sample reported experiencing high-power positions. Positional power and subjective feelings of power were strongly related but had unique relations with several individual difference measures and independent effects on participants' affect, cognition, and interpersonal relations. Subjective feelings of power resulted more from within-participant situational fluctuation, such as the social roles participants held at different times, than from stable differences between people. Our data supported some theoretical predictions about power's effects on affect, cognition, and interpersonal relations, but qualified others, particularly highlighting the role of responsibility in power's effects. Although the power literature has focused on high power, we found stronger effects of low power than high power.

  18. Automated recognition system for power quality disturbances

    NASA Astrophysics Data System (ADS)

    Abdelgalil, Tarek

    The application of deregulation policies in electric power systems has resulted in the necessity to quantify the quality of electric power. This fact highlights the need for a new monitoring strategy which is capable of tracking, detecting, classifying power quality disturbances, and then identifying the source of the disturbance. The objective of this work is to design an efficient and reliable power quality monitoring strategy that uses the advances in signal processing and pattern recognition to overcome the deficiencies that exist in power quality monitoring devices. The purposed monitoring strategy has two stages. The first stage is to detect, track, and classify any power quality violation by the use of on-line measurements. In the second stage, the source of the classified power quality disturbance must be identified. In the first stage, an adaptive linear combiner is used to detect power quality disturbances. Then, the Teager Energy Operator and Hilbert Transform are utilized for power quality event tracking. After the Fourier, Wavelet, and Walsh Transforms are employed for the feature extraction, two approaches are then exploited to classify the different power quality disturbances. The first approach depends on comparing the disturbance to be classified with a stored set of signatures for different power quality disturbances. The comparison is developed by using Hidden Markov Models and Dynamic Time Warping. The second approach depends on employing an inductive inference to generate the classification rules directly from the data. In the second stage of the new monitoring strategy, only the problem of identifying the location of the switched capacitor which initiates the transients is investigated. The Total Least Square-Estimation of Signal Parameters via Rotational Invariance Technique is adopted to estimate the amplitudes and frequencies of the various modes contained in the voltage signal measured at the facility entrance. After extracting the

  19. MPD thruster research issues, activities, strategies

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The following activities and plans in the MPD thruster development are summarized: (1) experimental and theoretical research (magnetic nozzles at present and high power levels, MPD thrusters with applied fields extending into the thrust chamber, and improved electrode performance); and (2) tools (MACH2 code for MPD and nozzle flow calculation, laser diagnostics and spectroscopy for non-intrusive measurements of flow conditions, and extension to higher power). National strategies are also outlined.

  20. Seismic Retrofit for Electric Power Systems

    SciTech Connect

    Romero, Natalia; Nozick, Linda K.; Dobson, Ian; Xu, Ningxiong; Jones, Dean A.

    2015-05-01

    Our paper develops a two-stage stochastic program and solution procedure to optimize the selection of seismic retrofit strategies to increase the resilience of electric power systems against earthquake hazards. The model explicitly considers the range of earthquake events that are possible and, for each, an approximation of the distribution of damage experienced. Furthermore, this is important because electric power systems are spatially distributed and so their performance is driven by the distribution of component damage. We also test this solution procedure against the nonlinear integer solver in LINGO 13 and apply the formulation and solution strategy to the Eastern Interconnection, where seismic hazard stems from the New Madrid seismic zone.

  1. Search in power-law networks

    NASA Astrophysics Data System (ADS)

    Adamic, Lada A.; Lukose, Rajan M.; Puniyani, Amit R.; Huberman, Bernardo A.

    2001-10-01

    Many communication and social networks have power-law link distributions, containing a few nodes that have a very high degree and many with low degree. The high connectivity nodes play the important role of hubs in communication and networking, a fact that can be exploited when designing efficient search algorithms. We introduce a number of local search strategies that utilize high degree nodes in power-law graphs and that have costs scaling sublinearly with the size of the graph. We also demonstrate the utility of these strategies on the GNUTELLA peer-to-peer network.

  2. Using ensemble NWP wind power forecasts to improve national power system management

    NASA Astrophysics Data System (ADS)

    Cannon, D.; Brayshaw, D.; Methven, J.; Coker, P.; Lenaghan, D.

    2014-12-01

    National power systems are becoming increasingly sensitive to atmospheric variability as generation from wind (and other renewables) increases. As such, the days-ahead predictability of wind power has significant implications for power system management. At this time horizon, power system operators plan transmission line outages for maintenance. In addition, forecast users begin to form backup strategies to account for the uncertainty in wind power predictions. Under-estimating this uncertainty could result in a failure to meet system security standards, or in the worst instance, a shortfall in total electricity supply. On the other hand, overly conservative assumptions about the forecast uncertainty incur costs associated with the unnecessary holding of reserve power. Using the power system of Great Britain (GB) as an example, we construct time series of GB-total wind power output using wind speeds from either reanalyses or global weather forecasts. To validate the accuracy of these data sets, wind power reconstructions using reanalyses and forecast analyses over a recent period are compared to measured GB-total power output. The results are found to be highly correlated on time scales greater than around 6 hours. Results are presented using ensemble wind power forecasts from several national and international forecast centres (obtained through TIGGE). Firstly, the skill with which global ensemble forecasts can represent the uncertainty in the GB-total power output at up to 10 days ahead is quantified. Following this, novel ensemble forecast metrics are developed to improve estimates of forecast uncertainty within the context of power system operations, thus enabling the development of more cost effective strategies. Finally, the predictability of extreme events such as prolonged low wind periods or rapid changes in wind power output are examined in detail. These events, if poorly forecast, induce high stress scenarios that could threaten the security of the power

  3. Reactive power management and voltage control in deregulated power markets

    NASA Astrophysics Data System (ADS)

    Spangler, Robert G.

    The research that is the subject of this dissertation is about the management of reactive power and voltage support in the wholesale open access power markets in the United States (US). The purpose of this research is to place decisions about open access market structures, as they relate to reactive power and voltage control, on a logical and consistent economic basis, given the engineering needs of a commercial electric power system. An examination of the electricity markets operating in the US today reveals that current approaches to reactive power management and voltage support are extensions of those based on historical, regulated monopoly electric service. A case for change is built by first looking at the subject of reactive power from an engineering viewpoint and then from an economic perspective. Ultimately, a set of market rules for managing reactive power and voltage support is proposed. The proposal suggests that cost recovery for static and dynamic VARs is appropriately accomplished through the regulated transmission cost of service. Static VAR cost recovery should follow traditional rate recovery methodologies. In the case of dynamic VARs, this work provides a methodology based on the microeconomic theory of the firm for determining such cost. It further suggests that an operational strategy that reduces and limits the use of dynamic VARs, during normal operations, is appropriate. This latter point leads to an increase in the fixed cost of the transmission network but prevents price spikes and short supply situations from affecting, or being affected by, the reactive capability limitations associated with dynamic VARs supplied from synchronous generators. The rules are consistent with a market structure that includes competitive generation and their application will result in the communication of a clear understanding of the responsibilities, related to voltage control, of each type of market entity. In this sense, their application will contribute to

  4. Power electronics for low power arcjets

    NASA Technical Reports Server (NTRS)

    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. 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.

  5. Negotiating strategies for capitation.

    PubMed

    Mildworm, L L

    1998-01-01

    The appropriate strategy to employ in contract negotiations will vary, depending on a number of important factors. These include the relative size and power of the network, the conditions of the local market, the strength of the managed-care payer in the market, and a host of other issues. The negotiating strategy ultimately adopted will be in accordance with the organizations overall preference, style, and needs. In approaching any contract negotiation, two key points should be kept in mind. First, networks must recognize they can become more prepared and empowered for contract negotiations through the acquisition of additional information. Second, form contracts can be changed; nothing is set in stone. Despite the frequent statements of payer organizations that the form cannot be modified to meet the provider's unique desires and needs, in most cases a contract can be modified in one way or another to meet the parties' mutual needs and desires. Everything is negotiable: Any party involved in such negotiations should be positive, avoiding conflict; use a problem-solving approach; agree whenever possible--strive to become "we"; acknowledge the payer's interest and position, expressing a desire to compromise; and acknowledge the authority and ability of the assigned negotiator. Once the managed-care contract is consummated, the network should attempt to ensure that the parties get maximum value from the agreement. One step to achieving such a desired end is to identify a leader who will be responsible for overseeing contract implementation and performance and responsible for knowing the requirements of the agreement inside out and for focusing on all other requirements of the managed-care program.

  6. Power Struggles. Beginnings Workshop.

    ERIC Educational Resources Information Center

    Neugebauer, Bonnie; Duffy, Roslyn; Garbarino, James; Gonzalez-Mena, Janet

    2001-01-01

    Presents four articles about children's power struggles: (1) "The Personal Side of Power" (Bonnie Neugebauer); (2) "Learning To Harness Human Power" (Roslyn Duffy); (3) "Power Struggles: Early Experiences Matter" (James Garbarino); and (4) "Personal Power: Creating New Realities" (Janet Gonzalez-Mena). (DLH)

  7. The Powers of Management.

    ERIC Educational Resources Information Center

    Farmer, Lesley S. J.

    2000-01-01

    Discusses the concept of power and how it relates to school libraries. Topics include personal power; organizational sources of power; organization versus power; the climate within a school, which influences decision making and collaboration; and the role of the library in sharing the power of resources and information. (LRW)

  8. Power Control of New Wind Power Generation System with Induction Generator Excited by Voltage Source Converter

    NASA Astrophysics Data System (ADS)

    Morizane, Toshimitsu; Kimura, Noriyuki; Taniguchi, Katsunori

    This paper investigates advantages of new combination of the induction generator for wind power and the power electronic equipment. Induction generator is popularly used for the wind power generation. The disadvantage of it is impossible to generate power at the lower rotor speed than the synchronous speed. To compensate this disadvantage, expensive synchronous generator with the permanent magnets is sometimes used. In proposed scheme, the diode rectifier is used to convert the real power from the induction generator to the intermediate dc voltage, while only the reactive power necessary to excite the induction generator is supplied from the voltage source converter (VSC). This means that the rating of the expensive VSC is minimized and total cost of the wind power generation system is decreased compared to the system with synchronous generator. Simulation study to investigate the control strategy of proposed system is performed. The results show the reduction of the VSC rating is prospective.

  9. Abrupt Strategy Change Underlies Gradual Performance Change: Bayesian Hierarchical Models of Component and Aggregate Strategy Use.

    PubMed

    Wynton, Sarah K A; Anglim, Jeromy

    2017-04-10

    While researchers have often sought to understand the learning curve in terms of multiple component processes, few studies have measured and mathematically modeled these processes on a complex task. In particular, there remains a need to reconcile how abrupt changes in strategy use can co-occur with gradual changes in task completion time. Thus, the current study aimed to assess the degree to which strategy change was abrupt or gradual, and whether strategy aggregation could partially explain gradual performance change. It also aimed to show how Bayesian methods could be used to model the effect of practice on strategy use. To achieve these aims, 162 participants completed 15 blocks of practice on a complex computer-based task-the Wynton-Anglim booking (WAB) task. The task allowed for multiple component strategies (i.e., memory retrieval, information reduction, and insight) that could also be aggregated to a global measure of strategy use. Bayesian hierarchical models were used to compare abrupt and gradual functions of component and aggregate strategy use. Task completion time was well-modeled by a power function, and global strategy use explained substantial variance in performance. Change in component strategy use tended to be abrupt, whereas change in global strategy use was gradual and well-modeled by a power function. Thus, differential timing of component strategy shifts leads to gradual changes in overall strategy efficiency, and this provides one reason for why smooth learning curves can co-occur with abrupt changes in strategy use. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  10. Nuclear power plant life extension

    SciTech Connect

    Carlson, D.D.; Bustard, L.D.; Harrison, D.L.

    1986-01-01

    Nuclear plant life extension represents an opportunity to achieve additional productive years of operation from existing nuclear power facilities. This is particularly important since operating licenses for over 50 GW of nuclear capacity will expire by the year 2010. By the year 2015, 85% of the total planned nuclear electric capacity will face retirement due to license expirations. Achieving additional productive years of operation from the nation's existing light water reactors is the goal of ongoing utility, vendor, US Department of Energy, and Electric Power Research Institute programs. Identifying potential technical issues associated with extending plant life and scoping realistic solutions represent first steps toward the development of a coordinated national plant life extension strategy. This is a substantial effort that must consider the breadth of issues associated with nuclear power plant design, operation, and licensing, and the numerous potential plant life extension strategies that may be appropriate to different utilities. Such an effort must enlist the expertise of the full spectrum of organizations in the nuclear industry including utilities, vendors, consultants, national laboratories, and professional organizations. A primary focus of these efforts is to identify operational changes and improvements in record-keeping, which, if implemented now, could enhance and preserve the life extension option.

  11. Infrared power cells for satellite power conversion

    NASA Technical Reports Server (NTRS)

    Summers, Christopher J.

    1991-01-01

    An analytical investigation is performed to assess the feasibility of long-wavelength power converters for the direct conversion of IR radiation onto electrical power. Because theses devices need to operate between 5 and 30 um the only material system possible for this application is the HgCdTe system which is currently being developed for IR detectors. Thus solar cell and IR detector theories and technologies are combined. The following subject areas are covered: electronic and optical properties of HgCdTe alloys; optimum device geometry; junction theory; model calculation for homojunction power cell efficiency; and calculation for HgCdTe power cell and power beaming.

  12. Solar powered multipurpose remotely powered aircraft

    NASA Technical Reports Server (NTRS)

    Alexandrou, A. N.; Durgin, W. W.; Cohn, R. F.; Olinger, D. J.; Cody, Charlotte K.; Chan, Agnes; Cheung, Kwok-Hung; Conley, Kristin; Crivelli, Paul M.; Javorski, Christian T.

    1992-01-01

    Increase in energy demands coupled with rapid depletion of natural energy resources have deemed solar energy as an attractive alternative source of power. The focus was to design and construct a solar powered, remotely piloted vehicle to demonstrate the feasibility of solar energy as an effective, alternate source of power. The final design included minimizing the power requirements and maximizing the strength-to-weight and lift-to-drag ratios. Given the design constraints, Surya (the code-name given to the aircraft), is a lightweight aircraft primarily built using composite materials and capable of achieving level flight powered entirely by solar energy.

  13. Green Power Partner Resources

    EPA Pesticide Factsheets

    EPA Green Power Partners can access tools and resources to help promote their green power commitments. Partners use these tools to communicate the benefits of their green power use to their customers, stakeholders, and the general public.

  14. Green Power Community News

    EPA Pesticide Factsheets

    This page features news about EPA's Green Power Communities. GPCs are a subset of the Green Power Partnership; municipalities or tribal governments where government, businesses, and residents collectively use enough green power to meet GPP requirements.

  15. Star Power: An Experiential Learning Exercise to Foster Ecological Perspectives on Power, Privilege, and Oppression

    PubMed Central

    Nnawulezi, Nkiru; Campbell, Christina; Landstra, Kalleigh; Davis, Se'ara; Vandegrift, Cortney; Taylor, Amanda

    2014-01-01

    The purpose of this article is to describe the utility of Star Power, as an experiential learning exercise applied in a community psychology undergraduate course. This exercise simulates systems of power, privilege, and oppression while fostering an ecological perspective that raises students’ awareness and knowledge about power differentials within society. The simulation of trading and lawmaking works best with 18 to 35 students and takes approximately 80 minutes to conduct. This paper highlights three representative student perspectives concerning their participation and experience with Star Power. Strategies for facilitating class discussion are also discussed. PMID:23480288

  16. Regional strategies for global leadership.

    PubMed

    Ghemawat, Pankaj

    2005-12-01

    The leaders of such global powerhouses as GE, Wal-Mart, and Toyota seem to have grasped two crucial truths: First, far from becoming submerged by the rising tide of globalization, geographic and other regional distinctions may in fact be increasing in importance. Second, regionally focused strategies, used in conjunction with local and global initiatives, can significantly boost a company's performance. The business and economic data reveal a highly regionalized world. For example, trade within regions, rather than across them, drove the surge of international commerce in the second half of the twentieth century. Regionalization is also apparent in foreign direct investment, companies' international sales, and competition among the world's largest multinationals. Harvard Business School Professor Pankaj Ghemawat says that the most successful companies employ five types of regional strategies in addition to--or even instead of--global ones: home base, portfolio, hub, platform, and mandate. Some companies adopt the strategies in sequence, but the most nimble switch from one to another and combine approaches as their markets and businesses evolve. At Toyota, for example, exports from the home base continue to be substantial even as the company builds up an international manufacturing presence. And as Toyota achieves economies of scale and scope with a strong network of hubs, the company also pursues economies of specialization through interregional mandates. Embracing regional strategies requires flexibility and creativity. A company must decide what constitutes a region, choose the most appropriate strategies, and mesh those strategies with the organization's existing structures. In a world that is neither truly global nor truly local, finding ways of coordinating within and across regions can deliver a powerful competitive advantage.

  17. Hydro power flexibility for power systems with variable renewable energy sources: an IEA Task 25 collaboration: Hydro power flexibility for power systems

    SciTech Connect

    Huertas-Hernando, Daniel; Farahmand, Hossein; Holttinen, Hannele; Kiviluoma, Juha; Rinne, Erkka; Söder, Lennart; Milligan, Michael; Ibanez, Eduardo; Martínez, Sergio Martín; Gomez-Lazaro, Emilio; Estanqueiro, Ana; Rodrigues, Luis; Carr, Luis; van Roon, Serafin; Orths, Antje Gesa; Eriksen, Peter Børre; Forcione, Alain; Menemenlis, Nickie

    2016-06-20

    Hydro power is one of the most flexible sources of electricity production. Power systems with considerable amounts of flexible hydro power potentially offer easier integration of variable generation, e.g., wind and solar. However, there exist operational constraints to ensure mid-/long-term security of supply while keeping river flows and reservoirs levels within permitted limits. In order to properly assess the effective available hydro power flexibility and its value for storage, a detailed assessment of hydro power is essential. Due to the inherent uncertainty of the weather-dependent hydrological cycle, regulation constraints on the hydro system, and uncertainty of internal load as well as variable generation (wind and solar), this assessment is complex. Hence, it requires proper modeling of all the underlying interactions between hydro power and the power system, with a large share of other variable renewables. A summary of existing experience of wind integration in hydro-dominated power systems clearly points to strict simulation methodologies. Recommendations include requirements for techno-economic models to correctly assess strategies for hydro power and pumped storage dispatch. These models are based not only on seasonal water inflow variations but also on variable generation, and all these are in time horizons from very short term up to multiple years, depending on the studied system. Another important recommendation is to include a geographically detailed description of hydro power systems, rivers' flows, and reservoirs as well as grid topology and congestion.

  18. Quantum Locality in Game Strategy

    NASA Astrophysics Data System (ADS)

    Melo-Luna, Carlos A.; Susa, Cristian E.; Ducuara, Andrés F.; Barreiro, Astrid; Reina, John H.

    2017-03-01

    Game theory is a well established branch of mathematics whose formalism has a vast range of applications from the social sciences, biology, to economics. Motivated by quantum information science, there has been a leap in the formulation of novel game strategies that lead to new (quantum Nash) equilibrium points whereby players in some classical games are always outperformed if sharing and processing joint information ruled by the laws of quantum physics is allowed. We show that, for a bipartite non zero-sum game, input local quantum correlations, and separable states in particular, suffice to achieve an advantage over any strategy that uses classical resources, thus dispensing with quantum nonlocality, entanglement, or even discord between the players’ input states. This highlights the remarkable key role played by pure quantum coherence at powering some protocols. Finally, we propose an experiment that uses separable states and basic photon interferometry to demonstrate the locally-correlated quantum advantage.

  19. Quantum Locality in Game Strategy

    PubMed Central

    Melo-Luna, Carlos A.; Susa, Cristian E.; Ducuara, Andrés F.; Barreiro, Astrid; Reina, John H.

    2017-01-01

    Game theory is a well established branch of mathematics whose formalism has a vast range of applications from the social sciences, biology, to economics. Motivated by quantum information science, there has been a leap in the formulation of novel game strategies that lead to new (quantum Nash) equilibrium points whereby players in some classical games are always outperformed if sharing and processing joint information ruled by the laws of quantum physics is allowed. We show that, for a bipartite non zero-sum game, input local quantum correlations, and separable states in particular, suffice to achieve an advantage over any strategy that uses classical resources, thus dispensing with quantum nonlocality, entanglement, or even discord between the players’ input states. This highlights the remarkable key role played by pure quantum coherence at powering some protocols. Finally, we propose an experiment that uses separable states and basic photon interferometry to demonstrate the locally-correlated quantum advantage. PMID:28327567

  20. Interplay of approximate planning strategies.

    PubMed

    Huys, Quentin J M; Lally, Níall; Faulkner, Paul; Eshel, Neir; Seifritz, Erich; Gershman, Samuel J; Dayan, Peter; Roiser, Jonathan P

    2015-03-10

    Humans routinely formulate plans in domains so complex that even the most powerful computers are taxed. To do so, they seem to avail themselves of many strategies and heuristics that efficiently simplify, approximate, and hierarchically decompose hard tasks into simpler subtasks. Theoretical and cognitive research has revealed several such strategies; however, little is known about their establishment, interaction, and efficiency. Here, we use model-based behavioral analysis to provide a detailed examination of the performance of human subjects in a moderately deep planning task. We find that subjects exploit the structure of the domain to establish subgoals in a way that achieves a nearly maximal reduction in the cost of computing values of choices, but then combine partial searches with greedy local steps to solve subtasks, and maladaptively prune the decision trees of subtasks in a reflexive manner upon encountering salient losses. Subjects come idiosyncratically to favor particular sequences of actions to achieve subgoals, creating novel complex actions or "options."